Implement Melee-style knockback stacking (#97)

## Summary

- stack residual airborne knockback per axis after the configured launch-frame threshold
- apply DI after combining the launch vectors while retaining the second hit's hitstun
- preserve and decay residual knockback after hitstun
- make stacking state rollback-safe and include it in debug save states
- clear launch state on landing, ledge interactions, KO, and respawn

## Testing

- `cargo check --tests`
- `cargo test` (159 tests passed)
- `git diff --check`

## Asset configuration

For Melee timing, `knockback_stacking_window` should be set to `10`. The local ignored asset package has been updated accordingly.

Reviewed-on: #97
Co-authored-by: Álex Román Núñez <eirexe@eirteam.moe>

.gitea/workflows/ci.yml

@@ -63,7 +63,6 @@ jobs:
             libxkbcommon-dev \
             libxkbcommon-x11-0 \
             mesa-vulkan-drivers \
-            blender \
             mold \
             pkg-config
 
@@ -130,22 +129,54 @@ jobs:
             libusb-1.0-0-dev \
             libwayland-dev \
             libx11-dev \
+            libxfixes3 \
+            libxi6 \
             libxkbcommon-dev \
             libxkbcommon-x11-0 \
+            blender \
             lld-19 \
             llvm-19 \
             mesa-vulkan-drivers \
             mold \
-            blender \
             pkg-config
           sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-19 100
           sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-19 100
           echo "/usr/lib/llvm-19/bin" >> "$GITHUB_PATH"
           rm -f "$HOME/.cache/cargo-xwin/clang-cl"
 
+      - name: Install pinned Blender
+        run: |
+          scripts/install-blender.sh "$RUNNER_TEMP/blender"
+          echo "BLENDER=$RUNNER_TEMP/blender/blender" >> "$GITHUB_ENV"
+
       - name: Preprocess assets
         run: cargo run --locked --bin process-assets --no-default-features --features debug_features -j 4
 
+      - name: Verify processed battlefield asset
+        run: |
+          python3 - <<'PY'
+          import json
+          import struct
+
+          path = "imported_assets/Default/stages/battlefield/bf2.blend"
+          with open(path, "rb") as asset:
+              header = asset.read(12)
+              if len(header) != 12:
+                  raise SystemExit(f"processed asset is truncated: {path}")
+              magic, version, length = struct.unpack("<4sII", header)
+              if magic != b"glTF" or version != 2 or length != asset.seek(0, 2):
+                  raise SystemExit(f"processed asset is not a valid GLB: {path}")
+              asset.seek(12)
+              json_length, chunk_type = struct.unpack("<II", asset.read(8))
+              if chunk_type != 0x4E4F534A:
+                  raise SystemExit(f"processed asset has no JSON chunk: {path}")
+              document = json.loads(asset.read(json_length))
+          meshes = document.get("meshes", [])
+          if not meshes:
+              raise SystemExit(f"processed asset contains no meshes: {path}")
+          print(f"{path}: {len(meshes)} meshes, {length} bytes")
+          PY
+
       - name: Build production binary
         run: cargo build --locked --profile production --no-default-features --features debug_features -j 4
 

Cargo.toml

@@ -7,21 +7,23 @@ authors = [""]
 [workspace]
 
 [features]
-default = ["development", "debug_features"]
+default = ["development", "debug_features", "gamecube-adapter"]
-development = ["bevy/dynamic_linking", "bevy/file_watcher"]
+development = ["bevy/dynamic_linking", "bevy/file_watcher", "bevy/embedded_watcher", "hitbox-viewer"]
+tracy = ["bevy/trace_tracy"]
 debug_features = ["bevy/free_camera"]
+gamecube-adapter = ["dep:gc-adapter-neo"]
+hitbox-viewer = ["bevy/bevy_dev_tools", "dep:egui_extras"]
 
 [dependencies]
-bevy = { version = "0.19", features = ["asset_processor", "basis-universal", "compressed_image_saver", "bevy_settings"] }
+bevy = { version = "0.19.1", features = ["asset_processor", "basis-universal", "compressed_image_saver", "bevy_settings"] }
-# Loads the scenes you author in the editor (assets/*.bsn) and builds
-# physics colliders from them. An ordinary dependency; remove it if you
-# stop using authored scenes.
 blake3 = { version = "1.8.5", features = [ "pure" ] }
+itertools = "0.15.0"
 thiserror = "2"
 avian3d = "0.7"
 arrayvec = "0.7.8"
 bevy-inspector-egui = "0.37.0"
 bevy_egui = "0.40.0"
+egui_extras = { version =  "0.34.3", optional = true}
 bevy_ggrs = { git = "https://github.com/gschup/bevy_ggrs" }
 serde = "1.0.229"
 serde_json = "1.0.145"
@@ -34,7 +36,6 @@ strum = "0.28.0"
 strum_macros = "0.28.0"
 bevy_asset_loader = "0.27.0"
 ron_asset_manager = "0.9.0"
-gc-adapter-neo = { version = "1.1.1", features = ["libusb"] }
 rhai = "1.26.0"
 enum_cycling = "0.2.1"
 enum_cycling_derive = "0.2.1"
@@ -49,3 +50,11 @@ inherits = "release"
 lto = "thin"
 codegen-units = 1
 strip = "symbols"
+
+[target.'cfg(not(target_os = "windows"))'.dependencies]
+gc-adapter-neo = { version = "1.1.1", features = ["libusb"], optional = true }
+
+[[bin]]
+name = "hitbox-editor"
+path = "src/bin/hitbox-editor.rs"
+required-features = ["hitbox-viewer"]

README.md

@@ -23,6 +23,19 @@ cargo run -- --debug-match --players 2 --local-port 7001 \
   --net-player 0=127.0.0.1:7000 --net-player 1=local
 ```
 
+## Hitbox viewer
+
+Run the live attack-script previewer with a fighter manifest and attack:
+
+```sh
+cargo run --bin hitbox-editor -- \
+  --manifest fighters/test/test.fighter.ron --attack jab
+```
+
+The timeline is read-only and refreshes through Bevy's asset hot reloading.
+Press Space to pause or resume, use the arrow keys to step, or click and drag
+the timeline to scrub.
+
 ## Production Build
 
 ```sh

assets/.lore/config.toml

@@ -1,15 +0,0 @@
-remote_url = "lore://lore.eirexe.moe"
-identity = "2"
-
-[store]
-max_capacity = 2000000
-eviction_delay = 30
-max_size = 10737418240
-compaction_delay = 50
-
-[file]
-direct_write = false
-flush_write = false
-
-[vfs]
-vfs_type = "None"

assets/catalog.bsn

@@ -1 +0,0 @@
-// no catalog entries

scripts/install-blender.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+version="5.2.2"
+sha256="84098912789dc450e95697c4184fb8a90acbe5111c2ba4aede3fecb57806a168"
+install_dir="${1:-${BLENDER_INSTALL_DIR:-${HOME}/.local/blender-${version}}}"
+
+if [[ "$(uname -s)" != Linux || "$(uname -m)" != x86_64 ]]; then
+    echo "error: this installer currently supports Linux x86_64 only" >&2
+    exit 1
+fi
+
+if [[ -x "$install_dir/blender" ]]; then
+    "$install_dir/blender" --version | head -n 1
+    exit 0
+fi
+
+mkdir -p "$(dirname "$install_dir")"
+tmp_dir="$(mktemp -d)"
+trap 'rm -rf "$tmp_dir"' EXIT
+
+archive="blender-${version}-linux-x64.tar.xz"
+url="https://download.blender.org/release/Blender5.2/${archive}"
+
+curl --fail --location --silent --show-error --output "$tmp_dir/$archive" "$url"
+printf '%s  %s\n' "$sha256" "$tmp_dir/$archive" | sha256sum --check --status
+tar --extract --xz --file "$tmp_dir/$archive" --directory "$tmp_dir"
+mv "$tmp_dir/blender-${version}-linux-x64" "$install_dir"
+
+"$install_dir/blender" --version | head -n 1

src/bin/hitbox-editor.rs

@@ -0,0 +1,37 @@
+use bevy::{
+    asset::{AssetMode, AssetPlugin},
+    gltf::GltfPlugin,
+    image::{ImageAddressMode, ImagePlugin, ImageSamplerDescriptor},
+    prelude::*,
+};
+use bevy_egui::EguiPlugin;
+use clap::Parser;
+use shinespark::hitbox_viewer::{HitboxViewerArgs, HitboxViewerPlugin};
+
+fn main() -> AppExit {
+    let args = HitboxViewerArgs::parse();
+    let default_sampler = ImageSamplerDescriptor::linear()
+        .set_address_mode(ImageAddressMode::Repeat)
+        .set_anisotropic_filter(16)
+        .clone();
+    let default_plugins = DefaultPlugins
+        .set(ImagePlugin {
+            default_sampler: default_sampler.clone(),
+        })
+        .set(GltfPlugin {
+            default_sampler,
+            ..default()
+        })
+        .set(AssetPlugin {
+            mode: AssetMode::Processed,
+            use_asset_processor_override: Some(cfg!(feature = "development")),
+            ..default()
+        });
+
+    App::new()
+        .add_plugins(default_plugins)
+        .add_plugins(EguiPlugin::default())
+        .insert_resource(args)
+        .add_plugins(HitboxViewerPlugin)
+        .run()
+}

src/blend_asset.rs

@@ -84,10 +84,11 @@ impl AssetLoader for BlendSourceLoader {
             .arg(&blend_path)
             .arg("--python")
             .arg(&script)
-        .arg("--")
+            .arg("--")
-        .arg(&output)
+            .arg(&output)
-        .arg(&actions_path)
+            .arg(&actions_path)
-        .output()
+            .arg(&blend_path)
+            .output()
             .map_err(|error| io::Error::other(format!("failed to start Blender: {error}")))?;
         if !result.status.success() {
             return Err(io::Error::other(format!(
@@ -106,6 +107,7 @@ impl AssetLoader for BlendSourceLoader {
         let mut dependencies = manifest.dependencies;
         let document: serde_json::Value = serde_json::from_slice(&fs::read(&output)?)
             .map_err(|error| io::Error::new(io::ErrorKind::InvalidData, error))?;
+        validate_export(&document, &output)?;
         if let Some(images) = document.get("images").and_then(serde_json::Value::as_array) {
             for image in images {
                 if let Some(uri) = image.get("uri").and_then(serde_json::Value::as_str) {
@@ -142,6 +144,22 @@ impl AssetLoader for BlendSourceLoader {
     }
 }
 
+fn validate_export(document: &serde_json::Value, output: &Path) -> io::Result<()> {
+    for key in ["scenes", "nodes", "meshes"] {
+        let count = document
+            .get(key)
+            .and_then(serde_json::Value::as_array)
+            .map_or(0, Vec::len);
+        if count == 0 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                format!("Blender export {} contains no {key}", output.display()),
+            ));
+        }
+    }
+    Ok(())
+}
+
 async fn referenced_actions(
     load_context: &mut LoadContext<'_>,
     root: &Path,

src/blend_asset/export.py

@@ -7,6 +7,15 @@ import sys
 def main():
     output = sys.argv[sys.argv.index("--") + 1]
     actions_path = sys.argv[sys.argv.index("--") + 2]
+    source_path = sys.argv[sys.argv.index("--") + 3]
+    loaded_path = os.path.realpath(bpy.data.filepath)
+    expected_path = os.path.realpath(source_path)
+    if loaded_path != expected_path:
+        raise RuntimeError(
+            f"Blender loaded {loaded_path!r} instead of {expected_path!r}"
+        )
+    if not bpy.data.objects or not bpy.data.meshes:
+        raise RuntimeError("Blender loaded an empty scene")
     with open(actions_path) as file:
         actions_to_keep = set(json.load(file))
 

src/camera/mod.rs

@@ -5,7 +5,7 @@ use bevy_ggrs::GgrsFrameTiming;
 
 use crate::{
     debug_tools::DebugSettings,
-    fighter::{manifest::FighterManifest, motion::sample_presentation_translation},
+    fighter::{manifest::FighterManifest, motion::{sample_presentation_translation_with_snap, FighterPresentationSnap}},
     stage::manifest::StageCameraProfile,
 };
 
@@ -313,6 +313,7 @@ fn update_match_camera(
             &crate::fighter::motion::FighterPreviousTranslation,
             &crate::fighter::Fighter,
             &crate::fighter::FighterFacingDirection,
+            &FighterPresentationSnap,
             &mut FighterCameraExtents,
         ),
         With<crate::player::Player>,
@@ -329,16 +330,17 @@ fn update_match_camera(
     let subjects = fighters
         .iter_mut()
         .map(
-            |(translation, previous_translation, fighter, facing, mut extents)| {
+            |(translation, previous_translation, fighter, facing, presentation_snap, mut extents)| {
                 let manifest = manifests
                     .get(&fighter.manifest)
                     .expect("Fighter manifest should be valid");
                 fighter_subject_bounds(
-                    sample_presentation_translation(
+                    sample_presentation_translation_with_snap(
                         *previous_translation,
                         *translation,
                         timing.overstep_fraction(),
                         debug_settings.motion_sampling,
+                        *presentation_snap,
                     ),
                     manifest.camera,
                     *facing,
@@ -465,6 +467,7 @@ fn debug_draw_camera(
             &crate::fighter::motion::FighterPreviousTranslation,
             &crate::fighter::Fighter,
             &crate::fighter::FighterFacingDirection,
+            &FighterPresentationSnap,
             &FighterCameraExtents,
         ),
         With<crate::player::Player>,
@@ -486,15 +489,16 @@ fn debug_draw_camera(
             Color::srgb(1.0, 0.5, 0.0),
         );
         draw_rectangle(&mut gizmos, camera.frame, Color::srgb(1.0, 1.0, 0.0));
-        for (translation, previous_translation, fighter, _facing, extents) in &fighters {
+        for (translation, previous_translation, fighter, _facing, presentation_snap, extents) in &fighters {
             let manifest = manifests
                 .get(&fighter.manifest)
                 .expect("Fighter manifest should be valid");
-            let center = sample_presentation_translation(
+            let center = sample_presentation_translation_with_snap(
                 *previous_translation,
                 *translation,
                 timing.overstep_fraction(),
                 debug_settings.motion_sampling,
+                *presentation_snap,
             ) + Vec2::Y * manifest.camera.vertical_origin_offset.to_num::<f32>();
             draw_rectangle(
                 &mut gizmos,

src/debug_tools.rs

@@ -3,11 +3,9 @@
 use std::{collections::HashMap, time::Duration};
 
 use bevy::{
-    input::InputSystems,
+    camera::{CameraOutputMode, visibility::RenderLayers}, input::InputSystems, prelude::*, render::render_resource::BlendState, settings::{ReflectSettingsGroup, SaveSettingsDeferred, SettingsGroup},
-    prelude::*,
-    settings::{ReflectSettingsGroup, SaveSettingsDeferred, SettingsGroup},
 };
-use bevy_egui::{EguiContexts, EguiPrimaryContextPass, egui};
+use bevy_egui::{EguiContexts, EguiGlobalSettings, EguiPrimaryContextPass, PrimaryEguiContext, egui};
 use bevy_ggrs::{RollbackFrameRate, RunGgrsSystems};
 use enum_cycling::EnumCycle;
 use enum_cycling_derive::EnumCycle;
@@ -111,11 +109,14 @@ impl FighterDebugRowKind {
 enum DebugFlag {
     Network,
     Ecb,
+    BlastZones,
     StageCollision,
+    SpawnPositions,
     AnimationBones,
     AttackHitboxes,
     Hurtboxes,
     Camera,
+    LedgeGrab,
     DrawThroughGeometry,
     FrameStepping,
 }
@@ -164,6 +165,10 @@ const FIGHTER_MENU: &[DebugMenuEntry] = &[
         label: "Attack hitboxes",
         flag: DebugFlag::AttackHitboxes,
     },
+    DebugMenuEntry::Toggle {
+        label: "Ledge grab",
+        flag: DebugFlag::LedgeGrab,
+    },
     DebugMenuEntry::Toggle {
         label: "Hurtboxes",
         flag: DebugFlag::Hurtboxes,
@@ -175,6 +180,14 @@ const WORLD_MENU: &[DebugMenuEntry] = &[
         label: "Stage collision",
         flag: DebugFlag::StageCollision,
     },
+    DebugMenuEntry::Toggle {
+        label: "Blast zones",
+        flag: DebugFlag::BlastZones,
+    },
+    DebugMenuEntry::Toggle {
+        label: "Spawn points",
+        flag: DebugFlag::SpawnPositions,
+    },
     DebugMenuEntry::GameSpeed {
         label: "Game speed",
     },
@@ -245,11 +258,14 @@ pub struct DebugSettings {
     pub frame_stepping: bool,
     pub network: bool,
     pub ecb: bool,
+    pub blast_zones: bool,
     pub stage_collision: bool,
+    pub spawn_positions: bool,
     pub animation_bones: bool,
     pub attack_hitboxes: bool,
     pub hurtboxes: bool,
     pub camera: bool,
+    pub ledge_grab: bool,
     pub draw_through_geometry: bool,
     pub motion_sampling: PresentationMotionMode,
     pub game_speed: GameSpeedDebug,
@@ -266,11 +282,14 @@ impl Default for DebugSettings {
             frame_stepping: false,
             network: false,
             ecb: false,
+            blast_zones: false,
             stage_collision: false,
+            spawn_positions: false,
             animation_bones: false,
             attack_hitboxes: false,
             hurtboxes: false,
             camera: false,
+            ledge_grab: false,
             draw_through_geometry: false,
             motion_sampling: PresentationMotionMode::default(),
             game_speed: GameSpeedDebug::Full,
@@ -330,12 +349,15 @@ impl DebugSettings {
         match flag {
             DebugFlag::Network => self.network,
             DebugFlag::Ecb => self.ecb,
+            DebugFlag::BlastZones => self.blast_zones,
+            DebugFlag::SpawnPositions => self.spawn_positions,
             DebugFlag::StageCollision => self.stage_collision,
             DebugFlag::AnimationBones => self.animation_bones,
             DebugFlag::AttackHitboxes => self.attack_hitboxes,
             DebugFlag::Hurtboxes => self.hurtboxes,
             DebugFlag::DrawThroughGeometry => self.draw_through_geometry,
             DebugFlag::Camera => self.camera,
+            DebugFlag::LedgeGrab => self.ledge_grab,
             DebugFlag::FrameStepping => self.frame_stepping,
         }
     }
@@ -344,7 +366,9 @@ impl DebugSettings {
         match flag {
             DebugFlag::Network => self.network = !self.network,
             DebugFlag::Ecb => self.ecb = !self.ecb,
+            DebugFlag::BlastZones => self.blast_zones = !self.blast_zones,
             DebugFlag::StageCollision => self.stage_collision = !self.stage_collision,
+            DebugFlag::SpawnPositions => self.spawn_positions = !self.spawn_positions,
             DebugFlag::AnimationBones => self.animation_bones = !self.animation_bones,
             DebugFlag::AttackHitboxes => self.attack_hitboxes = !self.attack_hitboxes,
             DebugFlag::Hurtboxes => self.hurtboxes = !self.hurtboxes,
@@ -352,6 +376,7 @@ impl DebugSettings {
                 self.draw_through_geometry = !self.draw_through_geometry
             }
             DebugFlag::Camera => self.camera = !self.camera,
+            DebugFlag::LedgeGrab => self.ledge_grab = !self.ledge_grab,
             DebugFlag::FrameStepping => self.frame_stepping = !self.frame_stepping,
         }
     }
@@ -397,6 +422,7 @@ impl Plugin for DebugToolsPlugin {
                     .before(RunGgrsSystems)
                     .run_if(in_state(AppState::InMatch)),
             )
+            .add_systems(Startup, spawn_egui_camera)
             .add_systems(PreUpdate, restore_frame_step_time.after(RunGgrsSystems))
             .add_systems(
                 Update,
@@ -408,6 +434,26 @@ impl Plugin for DebugToolsPlugin {
     }
 }
 
+pub fn spawn_egui_camera(mut commands: Commands, mut egui_global_settings: ResMut<EguiGlobalSettings>,) {
+    egui_global_settings.auto_create_primary_context = false;
+    commands.spawn((
+        // The `PrimaryEguiContext` component requires everything needed to render a primary context.
+        PrimaryEguiContext,
+        Camera2d,
+        // Setting RenderLayers to none makes sure we won't render anything apart from the UI.
+        RenderLayers::none(),
+        Camera {
+            order: 2,
+            output_mode: CameraOutputMode::Write {
+                blend_state: Some(BlendState::ALPHA_BLENDING),
+                clear_color: ClearColorConfig::None,
+            },
+            clear_color: ClearColorConfig::Custom(Color::NONE),
+            ..default()
+        },
+    ));
+}
+
 fn player_handles(players: &Query<&Player>) -> Vec<usize> {
     let mut handles = players
         .iter()
@@ -865,6 +911,14 @@ pub fn stage_collision_enabled(settings: Res<DebugSettings>) -> bool {
     settings.stage_collision
 }
 
+pub fn blast_zones_enabled(settings: Res<DebugSettings>) -> bool {
+    settings.blast_zones
+}
+
+pub fn spawn_positions_enabled(settings: Res<DebugSettings>) -> bool {
+    settings.spawn_positions
+}
+
 pub fn animation_bones_enabled(settings: Res<DebugSettings>) -> bool {
     settings.animation_bones
 }
@@ -881,6 +935,10 @@ pub fn camera_debug_enabled(settings: Res<DebugSettings>) -> bool {
     settings.camera
 }
 
+pub fn ledge_grab_enabled(settings: Res<DebugSettings>) -> bool {
+    settings.ledge_grab
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/debug_tools/save_state.rs

@@ -1,12 +1,26 @@
 use bevy::prelude::*;
 
 use crate::{
-    camera::MatchCamera, fighter::{
+    camera::MatchCamera,
-        FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop, FighterHitstopShake, FighterPreviousFacingDirection, FighterPreviousTranslation, FighterTranslation, FighterVelocity, Grounded, animation::FighterAnimationFrame, attack::{
+    fighter::{
-            FighterDamage, FighterKnockbackVelocity, FighterPendingHitReaction, FighterPendingHits,
+        FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop, FighterHitstopShake,
-            FighterSolvedHurtboxes, FighterStaleMoveQueue,
+        FighterInvulnerabilityState, FighterLedgeInformation, FighterPendingRespawn,
-        }, baked_animation::FighterBoneMatrices, state::FighterState,
+        FighterPreviousFacingDirection, FighterPreviousTranslation, FighterSurfaceState,
-    }, input::FighterInput, player::Player, stage::line::StageCollision,
+        FighterTranslation, FighterVelocity,
+        animation::FighterAnimationFrame,
+        attack::{
+            FighterDamage, FighterKnockbackState, FighterKnockbackVelocity,
+            FighterPendingHitReaction, FighterPendingHits, FighterSolvedHurtboxes,
+            FighterStaleMoveQueue,
+        },
+        baked_animation::FighterBoneMatrices,
+        ecb::FighterDesiredECB,
+        state::FighterState,
+    },
+    input::FighterInput,
+    match_runtime::MatchState,
+    player::Player,
+    stage::line::StageCollision,
 };
 
 #[derive(Resource, Default)]
@@ -19,6 +33,7 @@ struct Checkpoint {
     fighters: Vec<FighterCheckpoint>,
     stage_collision: StageCollision,
     pending_hits: FighterPendingHits,
+    match_state: MatchState,
 }
 
 #[derive(Clone)]
@@ -26,6 +41,7 @@ struct FighterCheckpoint {
     entity: Entity,
     handle: usize,
     ecb: FighterECB,
+    desired_ecb: FighterDesiredECB,
     previous_ecb: crate::fighter::ecb::FighterPreviousECB,
     velocity: FighterVelocity,
     translation: FighterTranslation,
@@ -40,11 +56,15 @@ struct FighterCheckpoint {
     hitstop: FighterHitstop,
     hitstop_shake: FighterHitstopShake,
     knockback_velocity: FighterKnockbackVelocity,
+    knockback_state: FighterKnockbackState,
     stale_moves: FighterStaleMoveQueue,
     hitboxes: FighterHitboxes,
     solved_hurtboxes: FighterSolvedHurtboxes,
     bone_matrices: FighterBoneMatrices,
-    grounded: bool,
+    surface: FighterSurfaceState,
+    pending_respawn: FighterPendingRespawn,
+    invulnerability_state: FighterInvulnerabilityState,
+    ledge_information: FighterLedgeInformation,
 }
 
 pub(super) fn save_or_restore(world: &mut World) {
@@ -89,10 +109,12 @@ pub(super) fn save_or_restore(world: &mut World) {
             checkpoint_fighters.push(checkpoint);
         }
         let pending_hits = world.resource::<FighterPendingHits>().clone();
+        let match_state = world.resource::<MatchState>().clone();
         world.resource_mut::<DebugSaveState>().checkpoint = Some(Checkpoint {
             fighters: checkpoint_fighters,
             stage_collision,
             pending_hits,
+            match_state,
         });
         info!("Saved debug game state");
         return;
@@ -125,6 +147,7 @@ pub(super) fn save_or_restore(world: &mut World) {
 
         let mut entity = world.entity_mut(saved.entity);
         entity.insert(saved.ecb);
+        entity.insert(saved.desired_ecb);
         entity.insert(saved.previous_ecb);
         entity.insert(saved.velocity);
         entity.insert(saved.translation);
@@ -139,18 +162,19 @@ pub(super) fn save_or_restore(world: &mut World) {
         entity.insert(saved.hitstop);
         entity.insert(saved.hitstop_shake);
         entity.insert(saved.knockback_velocity);
+        entity.insert(saved.knockback_state);
         entity.insert(saved.stale_moves.clone());
         entity.insert(saved.hitboxes.clone());
         entity.insert(saved.solved_hurtboxes.clone());
         entity.insert(saved.bone_matrices.clone());
-        if saved.grounded {
+        entity.insert(saved.surface.clone());
-            entity.insert(Grounded);
+        entity.insert(saved.pending_respawn.clone());
-        } else {
+        entity.insert(saved.invulnerability_state.clone());
-            entity.remove::<Grounded>();
+        entity.insert(saved.ledge_information.clone());
-        }
     }
     world.insert_resource(checkpoint.pending_hits.clone());
     world.insert_resource(checkpoint.stage_collision);
+    world.insert_resource(checkpoint.match_state);
     for mut match_camera in world.query::<&mut MatchCamera>().iter_mut(world) {
         match_camera.needs_snap = true;
     }
@@ -163,6 +187,7 @@ fn capture_fighter(world: &World, entity: Entity) -> Option<FighterCheckpoint> {
         entity,
         handle: fighter.get::<Player>()?.handle,
         ecb: *fighter.get::<FighterECB>()?,
+        desired_ecb: *fighter.get::<FighterDesiredECB>()?,
         previous_ecb: *fighter.get::<crate::fighter::ecb::FighterPreviousECB>()?,
         velocity: *fighter.get::<FighterVelocity>()?,
         translation: *fighter.get::<FighterTranslation>()?,
@@ -177,11 +202,15 @@ fn capture_fighter(world: &World, entity: Entity) -> Option<FighterCheckpoint> {
         hitstop: *fighter.get::<FighterHitstop>()?,
         hitstop_shake: *fighter.get::<FighterHitstopShake>()?,
         knockback_velocity: *fighter.get::<FighterKnockbackVelocity>()?,
+        knockback_state: *fighter.get::<FighterKnockbackState>()?,
         stale_moves: fighter.get::<FighterStaleMoveQueue>()?.clone(),
         hitboxes: fighter.get::<FighterHitboxes>()?.clone(),
         solved_hurtboxes: fighter.get::<FighterSolvedHurtboxes>()?.clone(),
         bone_matrices: fighter.get::<FighterBoneMatrices>()?.clone(),
-        grounded: fighter.contains::<Grounded>(),
+        surface: fighter.get::<FighterSurfaceState>()?.clone(),
+        pending_respawn: fighter.get::<FighterPendingRespawn>()?.clone(),
+        invulnerability_state: fighter.get::<FighterInvulnerabilityState>()?.clone(),
+        ledge_information: fighter.get::<FighterLedgeInformation>()?.clone(),
     })
 }
 

src/egui_color_convert.rs

@@ -0,0 +1,16 @@
+use bevy_egui::egui::Color32;
+
+pub trait ColorToEgui {
+    fn to_egui(&self) -> Color32;
+}
+
+impl ColorToEgui for bevy::color::Srgba {
+    fn to_egui(&self) -> Color32 {
+        Color32::from_rgba_unmultiplied(
+            (self.red * 255.0) as u8,
+            (self.green * 255.0) as u8,
+            (self.blue * 255.0) as u8,
+            (self.alpha * 255.0) as u8,
+        )
+    }
+}

src/fighter/animation.rs

@@ -84,6 +84,15 @@ pub enum AnimKind {
     AirDodge,
     Fall,
     Turn,
+    CrouchEnter,
+    CrouchIdle,
+    CrouchExit,
+    LedgeWait,
+    LedgeJump,
+    LedgeGetUp,
+    LedgeGrab,
+
+    PlatformPass,
 
     FlinchGround,
     FlinchAir,
@@ -93,4 +102,9 @@ pub enum AnimKind {
     AttackUpTilt,
     AttackForwardTilt,
     AttackDownTilt,
+    AttackNeutralAir,
+    AttackForwardAir,
+    AttackDownAir,
+    AttackDash,
+    AttackUpSmash,
 }

src/fighter/attack/directional_influence.rs

@@ -15,6 +15,16 @@ pub fn apply_directional_influence(
     let (sin, cos) = attack_angle.sin_cos();
     let base_launch_direction = FGVec2::new(cos, sin);
 
+    apply_directional_influence_to_direction(receiver_stick, base_launch_direction, di_max_angle)
+}
+
+/// Applies DI to an already-computed launch direction. This is used after
+/// knockback stacking, where the resulting angle may differ from either hit.
+pub fn apply_directional_influence_to_direction(
+    receiver_stick: FGVec2,
+    base_launch_direction: FGVec2,
+    di_max_angle: FGi32,
+) -> FGVec2 {
     let Some(base_launch_direction) = base_launch_direction.normalize() else {
         return FGVec2::ZERO;
     };
@@ -30,14 +40,20 @@ pub fn apply_directional_influence(
         -di_max_angle.to_fixed::<FGWide>(),
         di_max_angle.to_fixed::<FGWide>(),
     );
-    let (sin, cos) = (attack_angle + angle_change.to_fixed::<FGi32>()).sin_cos();
+    let (sin, cos) = angle_change.to_fixed::<FGi32>().sin_cos();
-    FGVec2::new(cos, sin).normalize_or_zero()
+    FGVec2::new(
+        base_launch_direction.x * cos - base_launch_direction.y * sin,
+        base_launch_direction.x * sin + base_launch_direction.y * cos,
+    )
+    .normalize_or_zero()
 }
 
 #[cfg(test)]
 mod test {
     use crate::{
-        fighter::attack::directional_influence::apply_directional_influence,
+        fighter::attack::directional_influence::{
+            apply_directional_influence, apply_directional_influence_to_direction,
+        },
         math::{int::FGi32, vec::FGVec2},
     };
 
@@ -66,4 +82,17 @@ mod test {
         assert!(di.x > FGi32::ZERO);
         assert!(di.y < FGi32::ZERO);
     }
+
+    #[test]
+    fn vector_di_preserves_a_stacked_direction_without_input() {
+        let direction = FGVec2::lit("-0.6", "0.8");
+        let result = apply_directional_influence_to_direction(
+            FGVec2::ZERO,
+            direction,
+            FGi32::lit("18.0"),
+        );
+        const EPSILON: FGi32 = FGi32::from_bits(6);
+        assert!(result.x.abs_diff(direction.x) < EPSILON);
+        assert!(result.y.abs_diff(direction.y) < EPSILON);
+    }
 }

src/fighter/attack/mod.rs

@@ -8,6 +8,7 @@ use bevy::prelude::*;
 use bevy_ggrs::{Rollback, RollbackApp, prelude::GgrsSchedule};
 use serde::{Deserialize, Serialize};
 
+use crate::fighter::FighterInvulnerabilityState;
 use crate::{
     fighter::{
         Fighter, FighterAttributes, FighterFacingDirection, FighterHitboxes,
@@ -32,7 +33,76 @@ use crate::{
 #[derive(Deref, Component, Default, Hash, Debug, Copy, Clone)]
 pub struct FighterKnockbackVelocity(pub FGVec2);
 
-#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize, Component, Hash, PartialEq)]
+/// Lifecycle state for the currently active launch velocity.
+///
+/// This counts frames where knockback was actually applied to movement; hitstop
+/// therefore does not advance it. Melee uses this age to decide whether a
+/// subsequent airborne hit replaces or stacks with the previous launch.
+#[derive(Component, Default, Hash, Debug, Copy, Clone)]
+pub struct FighterKnockbackState {
+    pub frames_since_launch: u32,
+}
+
+impl FighterKnockbackState {
+    pub fn restart(&mut self) {
+        self.frames_since_launch = 0;
+    }
+
+    pub fn clear(&mut self) {
+        self.frames_since_launch = 0;
+    }
+
+    pub fn advance(&mut self) {
+        self.frames_since_launch = self.frames_since_launch.saturating_add(1);
+    }
+
+    pub fn can_stack(&self, minimum_frames: u32) -> bool {
+        self.frames_since_launch >= minimum_frames
+    }
+}
+
+fn stack_knockback_component(previous: FGi32, new: FGi32) -> FGi32 {
+    if previous.is_zero() {
+        return new;
+    }
+    if new.is_zero() {
+        return previous;
+    }
+
+    if previous.signum() != new.signum() {
+        previous + new
+    } else if previous.abs() > new.abs() {
+        previous
+    } else {
+        new
+    }
+}
+
+/// Applies Melee's knockback-stacking rule independently to both axes.
+pub fn stack_knockback(previous: FGVec2, new: FGVec2) -> FGVec2 {
+    FGVec2::new(
+        stack_knockback_component(previous.x, new.x),
+        stack_knockback_component(previous.y, new.y),
+    )
+}
+
+pub fn decay_knockback(
+    velocity: &mut FighterKnockbackVelocity,
+    state: &mut FighterKnockbackState,
+    decay_per_frame: FGi32,
+) {
+    let speed = velocity.length();
+    let next_speed = speed.saturating_sub(decay_per_frame).max(FGi32::ZERO);
+    velocity.0 = velocity.normalize_or_zero() * next_speed;
+
+    if next_speed.is_zero() {
+        state.clear();
+    } else {
+        state.advance();
+    }
+}
+
+#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize, Component, Hash, PartialEq, Eq, PartialOrd, Ord)]
 pub struct FighterDamage(FGi32);
 
 impl std::fmt::Display for FighterDamage {
@@ -51,7 +121,8 @@ pub enum HitReactionKind {
 pub struct FighterHitReaction {
     pub launch_velocity: FGi32,
     pub launch_angle: FGi32,
-    pub hitstop_frames: HitStop,
+    pub victim_hitstop_frames: HitStop,
+    pub attacker_hitstop_frames: HitStop,
     pub hitstun_frames: u32,
     pub kind: HitReactionKind,
     pub damage: FighterDamage,
@@ -71,6 +142,53 @@ pub struct FighterLastAttackDebug {
     pub trajectory_points: Vec<Vec3>,
 }
 
+#[cfg(test)]
+mod knockback_stacking_tests {
+    use super::*;
+
+    #[test]
+    fn same_direction_keeps_the_stronger_component() {
+        assert_eq!(
+            stack_knockback(FGVec2::lit("3", "8"), FGVec2::lit("5", "4")),
+            FGVec2::lit("5", "8")
+        );
+    }
+
+    #[test]
+    fn opposing_components_add_independently() {
+        assert_eq!(
+            stack_knockback(FGVec2::lit("3", "8"), FGVec2::lit("-5", "-3")),
+            FGVec2::lit("-2", "5")
+        );
+    }
+
+    #[test]
+    fn opposing_components_can_cancel() {
+        assert_eq!(
+            stack_knockback(FGVec2::lit("3", "-4"), FGVec2::lit("-3", "4")),
+            FGVec2::ZERO
+        );
+    }
+
+    #[test]
+    fn zero_components_preserve_the_nonzero_value() {
+        assert_eq!(
+            stack_knockback(FGVec2::lit("0", "2"), FGVec2::lit("-3", "0")),
+            FGVec2::lit("-3", "2")
+        );
+    }
+
+    #[test]
+    fn stacking_threshold_is_inclusive() {
+        let mut state = FighterKnockbackState {
+            frames_since_launch: 9,
+        };
+        assert!(!state.can_stack(10));
+        state.advance();
+        assert!(state.can_stack(10));
+    }
+}
+
 #[derive(Debug, Default, Clone, Deref, DerefMut, Hash, PartialEq, PartialOrd)]
 pub struct HitStop(u32);
 
@@ -79,7 +197,7 @@ impl HitStop {
         HitStop(hitstop)
     }
     pub fn calculate(attack_damage_stalled: FighterDamage, crouch_cancelling: bool) -> Self {
-        let a = (attack_damage_stalled.0 / FGi32::lit("3.0") + FGi32::lit("4.0")).round_to_zero();
+        let a = (attack_damage_stalled.0 / FGi32::lit("3.0") + FGi32::lit("3.0")).round_to_zero();
         let crouch_cancelling_factor = if crouch_cancelling {
             FGi32::lit("0.66666666")
         } else {
@@ -96,6 +214,12 @@ impl HitStop {
     }
 }
 
+impl std::fmt::Display for HitStop {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
 #[derive(Clone, Copy, Debug, Serialize, Deserialize)]
 pub enum KnockbackType {
     Normal,
@@ -112,9 +236,15 @@ impl KnockbackType {
     }
 }
 
-#[derive(Debug, Default, Clone, Serialize, Deserialize)]
+#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
 pub struct Knockback(FGi32);
 
+impl std::fmt::Display for Knockback {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{:.2}", self.0)
+    }
+}
+
 impl Knockback {
     pub fn lit(val: &str) -> Self {
         Self(FGi32::lit(val))
@@ -143,6 +273,15 @@ pub enum AttackAngle {
     Sakurai,
 }
 
+impl std::fmt::Display for AttackAngle {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            AttackAngle::Normal(fixed_i32) => write!(f, "{:.2}º", fixed_i32),
+            AttackAngle::Sakurai => write!(f, "Sakurai"),
+        }
+    }
+}
+
 impl Default for AttackAngle {
     fn default() -> Self {
         AttackAngle::Normal(FGi32::lit("0"))
@@ -157,6 +296,30 @@ impl AttackAngle {
     pub fn make_sakurai() -> Self {
         Self::Sakurai
     }
+
+    pub fn get_angle(&self, knockback: &Knockback, is_receiver_grounded: bool, game_settings: &GameSettings) -> FGi32 {
+        match self {
+            AttackAngle::Normal(angle) => {
+                *angle
+            },
+            AttackAngle::Sakurai => {
+                if !is_receiver_grounded {
+                    game_settings.fighter_common.sakurai_angle_aerial_angle
+                } else if knockback.0 > game_settings.fighter_common.sakurai_angle_knockback_threshold {
+                    game_settings.fighter_common.sakurai_angle_high_knockback_angle
+                } else {
+                    game_settings.fighter_common.sakurai_angle_low_knockback_angle
+                }
+            },
+        }
+    }
+
+    pub fn to_melee_angle_representation(&self) -> FGi32 {
+        match self {
+            AttackAngle::Normal(fixed_i32) => *fixed_i32,
+            AttackAngle::Sakurai => FGi32::lit("361"),
+        }
+    }
 }
 
 #[derive(Serialize, Deserialize, Reflect, PartialEq, Eq, Hash, Clone, Debug, Default, Copy)]
@@ -174,23 +337,25 @@ pub enum AttackKind {
     UpSmash,
     DownSmash,
     ForwardSmash,
+    DashAttack,
 }
 
 impl AttackKind {
     pub fn get_animation(&self) -> AnimKind {
         match self {
-            AttackKind::NeutralAir => AnimKind::AttackJab1,
+            AttackKind::NeutralAir => AnimKind::AttackNeutralAir,
             AttackKind::Jab => AnimKind::AttackJab1,
             AttackKind::UpTilt => AnimKind::AttackUpTilt,
-            AttackKind::ForwardAir => AnimKind::AttackUpTilt,
+            AttackKind::ForwardAir => AnimKind::AttackForwardAir,
+            AttackKind::DownAir => AnimKind::AttackDownAir,
             AttackKind::BackAir => AnimKind::AttackUpTilt,
-            AttackKind::DownAir => AnimKind::AttackUpTilt,
             AttackKind::UpAir => AnimKind::AttackUpTilt,
             AttackKind::DownTilt => AnimKind::AttackDownTilt,
             AttackKind::ForwardTilt => AnimKind::AttackForwardTilt,
-            AttackKind::UpSmash => AnimKind::AttackUpTilt,
+            AttackKind::UpSmash => AnimKind::AttackUpSmash,
             AttackKind::DownSmash => AnimKind::AttackUpTilt,
             AttackKind::ForwardSmash => AnimKind::AttackUpTilt,
+            AttackKind::DashAttack => AnimKind::AttackDash,
         }
     }
 }
@@ -199,6 +364,7 @@ impl AttackKind {
 #[reflect(opaque)]
 pub struct AttackHitbox {
     pub id: u32,
+    pub group: u32,
     pub bone: String,
     pub damage: FighterDamage,
     pub offset: FGVec3,
@@ -211,6 +377,14 @@ pub struct AttackHitbox {
     pub end_frame: u32,
 }
 
+static ATTACK_HITBOX_ID_PALETTE: [bevy::color::Srgba; 5] = [
+    bevy::color::palettes::tailwind::RED_500,
+    bevy::color::palettes::tailwind::GREEN_500,
+    bevy::color::palettes::tailwind::BLUE_500,
+    bevy::color::palettes::tailwind::FUCHSIA_500,
+    bevy::color::palettes::tailwind::ORANGE_500,
+];
+
 const STALE_MOVE_QUEUE_COUNT: usize = 9;
 
 #[derive(Component, Hash, Clone, Default)]
@@ -258,6 +432,10 @@ impl FighterStaleMoveQueue {
 }
 
 impl AttackHitbox {
+    pub fn get_debug_draw_color(&self) -> bevy::color::Srgba {
+        ATTACK_HITBOX_ID_PALETTE[self.id as usize % ATTACK_HITBOX_ID_PALETTE.len()]
+    }
+
     pub fn validate(&self) -> Result<(), String> {
         if self.bone.trim().is_empty() {
             return Err("bone name is empty".into());
@@ -351,6 +529,36 @@ pub fn update_active_hitbox_list(script: &FighterAttackScript, list: &mut Vec<us
     );
 }
 
+/// Updates both the currently active hitbox intervals and the lifetime of
+/// their per-group victim histories. A group remains immune only while at
+/// least one hitbox belonging to that group is active.
+pub fn update_active_attack(
+    script: &FighterAttackScript,
+    attack: &mut super::FighterActiveAttack,
+    frame: u32,
+) {
+    update_active_hitbox_list(script, &mut attack.active_hitboxes, frame);
+
+    let mut active_groups = Vec::new();
+    for &index in &attack.active_hitboxes {
+        let group = script.hitboxes[index].group;
+        if !active_groups.contains(&group) {
+            active_groups.push(group);
+        }
+    }
+
+    attack.hit_groups.retain(|state| active_groups.contains(&state.group));
+    for group in active_groups {
+        if !attack.hit_groups.iter().any(|state| state.group == group) {
+            attack.hit_groups.push(super::FighterHitGroupState {
+                group,
+                hit_fighters: Vec::new(),
+            });
+        }
+    }
+    attack.hit_groups.sort_unstable_by_key(|state| state.group);
+}
+
 #[derive(Clone, Debug, PartialEq, Hash)]
 pub struct FighterSolvedHurtbox {
     pub hurtbox_idx: usize,
@@ -526,31 +734,33 @@ pub fn intersect_attacks_with_hurtboxes(
         &Player,
         &FighterStaleMoveQueue,
     )>,
-    query_attacked: Query<(Entity, &FighterSolvedHurtboxes)>,
+    query_attacked: Query<(Entity, &FighterSolvedHurtboxes, &FighterInvulnerabilityState)>,
     mut pending_hits: ResMut<FighterPendingHits>,
     attack_scripts: Res<Assets<FighterAttackScript>>,
 ) {
     pending_hits.0.clear();
 
     for &entity_receiving in &roster.0 {
-        let Ok((_, hurtboxes)) = query_attacked.get(entity_receiving) else {
+        let Ok((_, hurtboxes, invuln_state)) = query_attacked.get(entity_receiving) else {
             continue;
         };
 
+        if matches!(*invuln_state, FighterInvulnerabilityState::Intangible { .. }) {
+            continue;
+        }
+
         for &entity_hurting in &roster.0 {
             if entity_hurting == entity_receiving {
                 continue;
             }
+
+
             let Ok((_, mut hitboxes, _, _, _)) = query_attacker.get_mut(entity_hurting) else {
                 continue;
             };
             let Some(active_attack) = hitboxes.0.as_mut() else {
                 continue;
             };
-            if active_attack.hit_fighters.contains(&entity_receiving) {
-                continue;
-            }
-
             let attack_script = attack_scripts
                 .get(&active_attack.script)
                 .expect("Attack script should be valid");
@@ -560,6 +770,15 @@ pub fn intersect_attacks_with_hurtboxes(
                 for solved_hitbox in active_attack.solved_hitboxes.iter() {
                     if hurtbox.capsule.intersects(solved_hitbox.capsule) {
                         let candidate = solved_hitbox.hitbox_idx;
+                        let group = attack_script.hitboxes[candidate].group;
+                        let already_hit = active_attack
+                            .hit_groups
+                            .iter()
+                            .find(|state| state.group == group)
+                            .is_some_and(|state| state.hit_fighters.contains(&entity_receiving));
+                        if already_hit {
+                            continue;
+                        }
                         if hitting_hitbox_idx.is_none_or(|current: usize| {
                             attack_script.hitboxes[candidate].id
                                 < attack_script.hitboxes[current].id
@@ -581,9 +800,15 @@ pub fn intersect_attacks_with_hurtboxes(
                 attack_kind: active_attack.kind,
                 hitbox_index: hitting_hitbox_idx,
             });
-            info!("Hit by hitbox {}!!!!", hitting_hitbox_idx);
             
-            active_attack.hit_fighters.push(entity_receiving);
+            let group = attack_script.hitboxes[hitting_hitbox_idx].group;
+            if let Some(state) = active_attack
+                .hit_groups
+                .iter_mut()
+                .find(|state| state.group == group)
+            {
+                state.hit_fighters.push(entity_receiving);
+            }
         }
     }
 }
@@ -605,7 +830,6 @@ impl Plugin for FighterAttackPlugin {
                 intersect_attacks_with_hurtboxes,
             )
                 .chain()
-                .after(crate::fighter::baked_animation::update_fighter_bone_matrices)
                 .in_set(GameplaySet::Attacks),
         );
     }

src/fighter/attack/reaction.rs

@@ -4,21 +4,37 @@ use bevy_ggrs::prelude::GgrsSchedule;
 use super::*;
 use crate::{
     fighter::{
-        Fighter, FighterFacingDirection, FighterHitboxes, FighterHitstop, FighterHitstopShake, FighterHitstopShakeKind, FighterHitstopShakeRole, FighterPendingHitReaction, FighterStaleMoveQueue, errors::FighterErrors, manifest::FighterManifest, state::FighterState,
+        Fighter, FighterHitboxes, FighterHitstop, FighterHitstopShake,
-    }, game_settings::GameSettings, math::{int::FGi32}, player::Player, schedule::GameplaySet, scripting::FighterAttackScript,
+        FighterHitstopShakeKind, FighterHitstopShakeRole, FighterPendingHitReaction,
+        FighterStaleMoveQueue, FighterSurfaceState, errors::FighterErrors,
+        manifest::FighterManifest, state::FighterState,
+    },
+    game_settings::GameSettings,
+    math::int::FGi32,
+    player::Player,
+    schedule::GameplaySet,
+    scripting::FighterAttackScript,
 };
 
 pub fn resolve_fighter_hits(
     mut pending_hits: ResMut<FighterPendingHits>,
     mut attacker: Query<(
         &mut FighterStaleMoveQueue,
-        &FighterFacingDirection,
         &mut FighterHitboxes,
         &Player,
         &mut FighterHitstop,
         &mut FighterHitstopShake,
+        &FighterTranslation,
+    )>,
+    mut receiver: Query<(
+        &mut FighterDamage,
+        &Fighter,
+        &mut FighterPendingHitReaction,
+        &FighterState,
+        &FighterInvulnerabilityState,
+        &FighterSurfaceState,
+        &FighterTranslation,
     )>,
-    mut receiver: Query<(&mut FighterDamage, &Fighter, &mut FighterPendingHitReaction, &FighterState)>,
     attack_scripts: Res<Assets<FighterAttackScript>>,
     game_settings: Res<GameSettings>,
     fighter_manifests: Res<Assets<FighterManifest>>,
@@ -33,7 +49,15 @@ pub fn resolve_fighter_hits(
             .position(|hit| hit.defender != defender)
             .map_or(hits.len(), |offset| hit_offset + offset);
 
-        let Ok((mut receiver_damage, fighter, mut pending_reaction, receiver_state)) = receiver.get_mut(defender)
+        let Ok((
+            mut receiver_damage,
+            fighter,
+            mut pending_reaction,
+            receiver_state,
+            invuln_state,
+            receiver_surface_state,
+            receiver_translation,
+        )) = receiver.get_mut(defender)
         else {
             hit_offset = next_defender;
             continue;
@@ -42,7 +66,7 @@ pub fn resolve_fighter_hits(
         let damage_data = hits[hit_offset..next_defender]
             .iter()
             .filter_map(|hit| {
-                let Ok((stale_move_queue, facing_dir, _, player, _, _)) =
+                let Ok((stale_move_queue, _, player, _, _, attacker_translation)) =
                     attacker.get(hit.attacker)
                 else {
                     return None;
@@ -52,12 +76,13 @@ pub fn resolve_fighter_hits(
                 let damage_received = stale_move_queue
                     .get_attack_damage_multiplier(hit.attack_kind)
                     * hitbox.damage.0;
+                let angle_flip = receiver_translation.0.x <= attacker_translation.0.x;
                 Some((
                     hit.attacker,
                     damage_received,
                     hitbox,
-                    matches!(facing_dir, FighterFacingDirection::Left),
                     player.handle,
+                    angle_flip,
                 ))
             })
             .collect::<Vec<_>>();
@@ -71,26 +96,35 @@ pub fn resolve_fighter_hits(
             .ok_or(FighterErrors::FighterManifestNotFound)?;
         let mut reactions = Vec::with_capacity(damage_data.len());
 
-        for (attacker_entity, attack_damage, hitbox, facing_left, attacker_slot) in damage_data {
+        let crouch_canceling = if let FighterState::Crouch(crouch_state) = &receiver_state {
+            crouch_state.is_crouch_cancelling()
+        } else {
+            false
+        };
+
+        for (attacker_entity, attack_damage, hitbox, attacker_slot, angle_flip) in damage_data {
             let knockback = hitbox.calculate_knockback(
                 &fighter_manifest.attributes,
                 *receiver_damage,
                 FighterDamage(total_damage_received_this_frame),
                 false,
-                false,
+                crouch_canceling,
             );
-            let angle = match &hitbox.angle {
+            let launch_angle = hitbox.angle.get_angle(
-                AttackAngle::Normal(angle) => *angle,
+                &knockback,
-                AttackAngle::Sakurai => FGi32::lit("32.0"),
+                receiver_surface_state.is_grounded(),
-            };
+                &game_settings,
-            let launch_angle = if facing_left {
+            );
-                FGi32::lit("180.0") - angle
+
+            let launch_angle = if angle_flip {
+                FGi32::lit("180.0") - launch_angle
             } else {
-                angle
+                launch_angle
             };
 
             // Attacker hitstop and data
-            let hitstop = HitStop::calculate(FighterDamage(attack_damage), false);
+            let victim_hitstop_frames = HitStop::calculate(FighterDamage(attack_damage), crouch_canceling);
+            let attacker_hitstop_frames = HitStop::calculate(FighterDamage(attack_damage), false);
             reactions.push((
                 attacker_entity,
                 attacker_slot,
@@ -98,28 +132,37 @@ pub fn resolve_fighter_hits(
                     launch_velocity: knockback.get_launch_speed(&game_settings),
                     launch_angle,
                     hitstun_frames: knockback.get_hitstun_frames(&game_settings),
-                    hitstop_frames: hitstop,
+                    victim_hitstop_frames,
+                    attacker_hitstop_frames,
                     kind: HitReactionKind::Flinch,
-                    damage: FighterDamage(attack_damage)
+                    damage: FighterDamage(attack_damage),
                 },
             ));
         }
 
-        receiver_damage.0 += total_damage_received_this_frame;
+        match invuln_state {
+            FighterInvulnerabilityState::Vulnerable => {
+                receiver_damage.0 += total_damage_received_this_frame
+            }
+            _ => (),
+        }
 
         for (attacker_entity, _, reaction) in &reactions {
-            let Ok((.., _, mut hitstop, mut hitstop_shake)) = attacker.get_mut(*attacker_entity) else {
+            let Ok((.., _, mut hitstop, mut hitstop_shake, _)) = attacker.get_mut(*attacker_entity)
+            else {
                 continue;
             };
 
-            if hitstop.remaining_frames < reaction.hitstop_frames.0 {
+            if hitstop.remaining_frames < reaction.attacker_hitstop_frames.0 {
                 let shake_kind = if receiver_state.is_visually_grounded() {
                     FighterHitstopShakeKind::Horizontal
                 } else {
                     FighterHitstopShakeKind::Vertical
                 };
-                hitstop.remaining_frames = reaction.hitstop_frames.0;
+                hitstop.remaining_frames = reaction.attacker_hitstop_frames.0;
-                let shake_frames = reaction.hitstop_frames.calculate_shake_frames(&game_settings);
+                let shake_frames = reaction
+                    .attacker_hitstop_frames
+                    .calculate_shake_frames(&game_settings);
                 hitstop_shake.total_frames = shake_frames;
                 hitstop_shake.remaining_frames = shake_frames;
                 hitstop_shake.kind = shake_kind;
@@ -127,16 +170,23 @@ pub fn resolve_fighter_hits(
             }
         }
 
-        pending_reaction.0 = reactions
+        match invuln_state {
-            .into_iter()
+            FighterInvulnerabilityState::Vulnerable => {
-            .min_by(|(_, port_a, _), (_, port_b, _)| port_a.cmp(port_b))
+                pending_reaction.0 = reactions
-            .map(|(_, _, reaction)| reaction);
+                    .into_iter()
+                    .min_by(|(_, port_a, _), (_, port_b, _)| port_a.cmp(port_b))
+                    .map(|(_, _, reaction)| reaction);
+            }
+            _ => (),
+        }
 
         hit_offset = next_defender;
     }
 
     for hit in hits {
-        let Ok((mut stale_move_queue, _facing_direction, mut hitboxes, ..)) = attacker.get_mut(hit.attacker) else {
+        let Ok((mut stale_move_queue, mut hitboxes, ..)) =
+            attacker.get_mut(hit.attacker)
+        else {
             continue;
         };
 

src/fighter/attributes.rs

@@ -9,6 +9,10 @@ use crate::{input::FighterInputFrame, math::int::FGi32};
 #[derive(Asset, Clone, Copy, Reflect, Serialize, Deserialize)]
 #[reflect(opaque)]
 pub struct FighterAttributes {
+    /// Fixed horizontal offset of the fighter's grounded pushbox center.
+    pub pushbox_offset: FGi32,
+    /// Fixed horizontal radius used for grounded fighter-to-fighter pushing.
+    pub pushbox_radius: FGi32,
     pub base_walk_accel: FGi32,
     pub stick_walk_accel: FGi32,
     pub max_walk_vel: FGi32,
@@ -44,6 +48,11 @@ pub struct FighterAttributes {
     pub air_dodge_duration: u32,
     pub air_dodge_velocity: FGi32,
     pub air_dodge_decay: FGi32,
+
+    pub air_dodge_intangible_duration: u32,
+    pub air_dodge_intangible_start: u32,
+
+    pub dash_attack_cancel_window: u32,
 }
 
 impl FighterAttributes {
@@ -51,6 +60,9 @@ impl FighterAttributes {
         if self.weight <= FGi32::ZERO {
             return Err("weight must be positive".into());
         }
+        if self.pushbox_radius <= FGi32::ZERO {
+            return Err("pushbox radius must be positive".into());
+        }
         Ok(())
     }
 

src/fighter/baked_animation/asset_baking.rs

@@ -27,6 +27,7 @@ struct FighterBakeSource {
     model_bytes: Vec<u8>,
     buffers: Vec<Vec<u8>>,
     animations: HashMap<AnimKind, String>,
+    root_motion_bone: String,
 }
 #[derive(Default, TypePath)]
 struct FighterBakeSourceLoader;
@@ -82,6 +83,7 @@ impl AssetLoader for FighterBakeSourceLoader {
             model_bytes,
             buffers,
             animations: manifest.animations,
+            root_motion_bone: manifest.root_motion_bone,
         })
     }
     fn extensions(&self) -> &[&str] {
@@ -123,7 +125,12 @@ impl AssetTransformer for FighterBakeTransformer {
         source: TransformedAsset<Self::AssetInput>,
         _: &'a Self::Settings,
     ) -> Result<TransformedAsset<Self::AssetOutput>, Self::Error> {
-        let baked = bake_gltf(&source.model_bytes, &source.buffers, &source.animations)?;
+        let baked = bake_gltf(
+            &source.model_bytes,
+            &source.buffers,
+            &source.animations,
+            &source.root_motion_bone,
+        )?;
         Ok(source.replace_asset(baked))
     }
 }
@@ -154,6 +161,7 @@ type FighterBakeProcessor = LoadTransformAndSave<
 >;
 
 pub struct BakedAnimationPlugin;
+pub struct BakedAnimationVisualPlugin;
 
 pub struct BakedAnimationAssetProcessingPlugin;
 
@@ -172,17 +180,27 @@ impl Plugin for BakedAnimationAssetProcessingPlugin {
 
 impl Plugin for BakedAnimationPlugin {
     fn build(&self, app: &mut App) {
-        app.add_plugins(BakedAnimationAssetProcessingPlugin)
+        app.add_plugins((
-            .add_systems(
+            BakedAnimationAssetProcessingPlugin,
-                bevy_ggrs::prelude::GgrsSchedule,
+            BakedAnimationVisualPlugin,
-                super::runtime::update_fighter_bone_matrices
+        ))
-                    .in_set(crate::schedule::GameplaySet::Animation),
+        .add_systems(
-            )
+            bevy_ggrs::prelude::GgrsSchedule,
-            .add_systems(
+            super::runtime::update_fighter_bone_matrices
-                Update,
+                .in_set(super::BakedAnimationSamplingSet)
-                super::visual_binding::apply_baked_fighter_visual_pose,
+                .in_set(crate::schedule::GameplaySet::Animation),
-            )
+        );
-            .add_observer(super::visual_binding::bind_fighter_visual_bones);
+    }
+}
+
+impl Plugin for BakedAnimationVisualPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(
+            Update,
+            super::visual_binding::apply_baked_fighter_visual_pose
+                .after(super::BakedAnimationSamplingSet),
+        )
+        .add_observer(super::visual_binding::bind_fighter_visual_bones);
     }
 }
 
@@ -190,6 +208,7 @@ fn bake_gltf(
     bytes: &[u8],
     buffer_bytes: &[Vec<u8>],
     animations: &HashMap<AnimKind, String>,
+    root_motion_bone: &str,
 ) -> io::Result<BakedFighterAnimations> {
     let gltf = gltf::Gltf::from_slice(bytes)
         .map_err(|error| io::Error::new(io::ErrorKind::InvalidData, error))?;
@@ -217,13 +236,14 @@ fn bake_gltf(
             "glTF buffer data is incomplete",
         ));
     }
-    bake_gltf_document(gltf.document, buffers, animations)
+    bake_gltf_document(gltf.document, buffers, animations, root_motion_bone)
 }
 
 pub(super) fn bake_gltf_document(
     document: gltf::Document,
     buffers: Vec<gltf::buffer::Data>,
     animations: &HashMap<AnimKind, String>,
+    root_motion_bone: &str,
 ) -> io::Result<BakedFighterAnimations> {
     let nodes: Vec<_> = document.nodes().collect();
     if nodes.is_empty() {
@@ -249,6 +269,15 @@ pub(super) fn bake_gltf_document(
             })
         })
         .collect::<io::Result<Vec<_>>>()?;
+    let root_bone_index = names
+        .iter()
+        .position(|name| name == root_motion_bone)
+        .ok_or_else(|| {
+            io::Error::new(
+                io::ErrorKind::InvalidData,
+                format!("fighter model has no root-motion bone named {root_motion_bone}"),
+            )
+        })?;
     let mut pending = HashMap::<&str, Vec<AnimKind>>::new();
     for (kind, name) in animations {
         pending.entry(name).or_default().push(*kind);
@@ -275,17 +304,28 @@ pub(super) fn bake_gltf_document(
             .fold(0.0_f32, f32::max);
         let frame_count = baked_frame_count(duration, BAKED_ANIMATION_FPS);
         let mut frames = Vec::with_capacity(frame_count);
+        let mut root_positions = Vec::with_capacity(frame_count);
         for frame in 0..frame_count {
             let time = (frame as f32 / BAKED_ANIMATION_FPS as f32).min(duration);
-            frames.push(
+            let local = nodes
-                nodes
+                .iter()
-                    .iter()
+                .map(|node| local_transform(node.clone(), &channels, time))
-                    .map(|node| local_transform(node.clone(), &channels, time))
+                .collect::<io::Result<Vec<_>>>()?;
-                    .collect::<io::Result<Vec<_>>>()?,
+            let mut model = vec![None; local.len()];
-            );
+            let root = super::runtime::resolve_model_transform(
+                root_bone_index,
+                &parents,
+                &local,
+                &mut model,
+            )?;
+            root_positions.push(root.get_translation());
+            frames.push(local);
         }
         let index = clips.len();
-        clips.push(BakedAnimationClip { frames });
+        clips.push(BakedAnimationClip {
+            frames,
+            root_positions,
+        });
         for kind in kinds {
             clip_indices.insert(kind, index);
         }
@@ -311,6 +351,7 @@ pub(super) fn bake_gltf_document(
         frame_rate: BAKED_ANIMATION_FPS,
         bone_names: names,
         parents,
+        root_bone_index,
         clips,
         clip_indices,
     })

src/fighter/baked_animation/mod.rs

@@ -5,12 +5,17 @@ mod runtime;
 mod visual_binding;
 
 pub use crate::math::fixed_transform::FixedMat4;
-pub use asset_baking::{BakedAnimationAssetProcessingPlugin, BakedAnimationPlugin};
+pub use asset_baking::{
+    BakedAnimationAssetProcessingPlugin, BakedAnimationPlugin, BakedAnimationVisualPlugin,
+};
 pub use runtime::{
     BakedAnimationClip, BakedFighterAnimations, FighterBoneIndexMap, FighterBoneMatrices,
-    update_fighter_bone_matrices,
+    resample_fighter_bone_matrices, update_fighter_bone_matrices,
 };
 
+#[derive(bevy::prelude::SystemSet, Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct BakedAnimationSamplingSet;
+
 pub const BAKED_ANIMATION_FPS: u32 = 60;
 
 #[cfg(test)]
@@ -31,7 +36,13 @@ mod tests {
         ))
         .unwrap();
         let (document, buffers) = test_gltf(&manifest.animations);
-        let baked = bake_gltf_document(document, buffers, &manifest.animations).unwrap();
+        let baked = bake_gltf_document(
+            document,
+            buffers,
+            &manifest.animations,
+            &manifest.root_motion_bone,
+        )
+        .unwrap();
 
         assert_eq!(baked.frame_rate, BAKED_ANIMATION_FPS);
         assert_eq!(baked.frame_count(AnimKind::Wait), Some(121));
@@ -46,6 +57,15 @@ mod tests {
             baked.bone_names.len()
         );
         assert_eq!(baked.parents.len(), baked.bone_names.len());
+        assert_eq!(baked.root_bone_index, 0);
+        assert_eq!(
+            baked.initial_root_position(AnimKind::Wait, FGi32::lit("2")),
+            Some(FGVec3::ZERO)
+        );
+        assert_eq!(
+            baked.root_motion_cycle_delta(AnimKind::Wait, FGi32::lit("2")),
+            Some(FGVec3::lit("2", "0", "0"))
+        );
     }
 
     /// Builds the smallest glTF document that still exercises the complete
@@ -157,8 +177,14 @@ mod tests {
             frame_rate: BAKED_ANIMATION_FPS,
             bone_names: vec!["root".into()],
             parents: vec![None],
+            root_bone_index: 0,
             clips: vec![BakedAnimationClip {
                 frames: vec![vec![first], vec![second], vec![terminal]],
+                root_positions: vec![
+                    FGVec3::ZERO,
+                    FGVec3::lit("2", "0", "0"),
+                    FGVec3::lit("4", "0", "0"),
+                ],
             }],
             clip_indices: HashMap::from([(AnimKind::Wait, 0)]),
         };
@@ -219,6 +245,7 @@ mod tests {
         second.translate(FGVec3::lit("0", "3", "0"));
         let mut matrices = FighterBoneMatrices::default();
         matrices.set_pose(
+            AnimKind::Wait,
             &["root".into(), "hand".into()],
             &[None, Some(0)],
             &[first, second],
@@ -239,6 +266,7 @@ mod tests {
         hand.translate(FGVec3::lit("0", "3", "0"));
         let mut matrices = FighterBoneMatrices::default();
         matrices.set_pose(
+            AnimKind::Wait,
             &["root".into(), "hand".into()],
             &[None, Some(0)],
             &[root, hand],
@@ -266,13 +294,38 @@ mod tests {
         let parents = [None, Some(0)];
         let pose = [FixedMat4::IDENTITY, FixedMat4::IDENTITY];
 
-        matrices.set_pose(&names, &parents, &pose, FGi32::ONE);
+        matrices.set_pose(AnimKind::Wait, &names, &parents, &pose, FGi32::ONE);
         let capacities = matrices.buffer_capacities();
-        matrices.set_pose(&names, &parents, &pose, FGi32::ONE);
+        matrices.set_pose(AnimKind::Wait, &names, &parents, &pose, FGi32::ONE);
 
         assert_eq!(capacities, matrices.buffer_capacities());
     }
 
+    #[test]
+    fn same_frame_resample_preserves_previous_gameplay_pose() {
+        let names = ["root".into()];
+        let parents = [None];
+        let mut pose_a = FixedMat4::IDENTITY;
+        pose_a.translate(FGVec3::lit("1", "0", "0"));
+        let mut pose_b = FixedMat4::IDENTITY;
+        pose_b.translate(FGVec3::lit("2", "0", "0"));
+        let mut snapped_pose = FixedMat4::IDENTITY;
+        snapped_pose.translate(FGVec3::lit("3", "0", "0"));
+        let mut matrices = FighterBoneMatrices::default();
+
+        matrices.set_pose(AnimKind::Wait, &names, &parents, &[pose_a], FGi32::ONE);
+        matrices.set_pose(AnimKind::Wait, &names, &parents, &[pose_b], FGi32::ONE);
+        matrices.resample_pose(
+            AnimKind::Landing,
+            &names,
+            &parents,
+            &[snapped_pose],
+            FGi32::ONE,
+        );
+
+        assert_eq!(matrices.get_index(0), Some((pose_a, snapped_pose)));
+    }
+
     #[test]
     fn model_scale_affects_gameplay_bones_without_changing_visual_locals() {
         let mut root = FixedMat4::IDENTITY;
@@ -281,6 +334,7 @@ mod tests {
         hand.translate(FGVec3::lit("0", "2", "0"));
         let mut matrices = FighterBoneMatrices::default();
         matrices.set_pose(
+            AnimKind::Wait,
             &["root".into(), "hand".into()],
             &[None, Some(0)],
             &[root, hand],
@@ -293,6 +347,180 @@ mod tests {
         );
     }
 
+    #[test]
+    fn root_motion_delta_is_scaled_and_zero_on_initial_sample() {
+        let names = ["root".into()];
+        let parents = [None];
+        let mut first = FixedMat4::IDENTITY;
+        first.translate(FGVec3::lit("1", "0", "0"));
+        let mut second = FixedMat4::IDENTITY;
+        second.translate(FGVec3::lit("3", "0", "0"));
+        let mut matrices = FighterBoneMatrices::default();
+        let frame = crate::fighter::animation::FighterAnimationFrame::new(AnimKind::Wait, false);
+
+        matrices.set_pose_with_frame(
+            frame,
+            Some(0),
+            Some(FGVec3::lit("2", "0", "0")),
+            FGVec3::ZERO,
+            None,
+            AnimKind::Wait,
+            &names,
+            &parents,
+            &[first],
+            FGi32::lit("2"),
+        );
+        assert_eq!(matrices.root_motion_delta(), FGVec3::ZERO);
+        assert_eq!(
+            matrices.root_motion_position(),
+            Some(FGVec3::lit("2", "0", "0"))
+        );
+
+        matrices.set_pose_with_frame(
+            crate::fighter::animation::FighterAnimationFrame { frame: 1, ..frame },
+            Some(0),
+            Some(FGVec3::lit("6", "0", "0")),
+            FGVec3::ZERO,
+            None,
+            AnimKind::Wait,
+            &names,
+            &parents,
+            &[second],
+            FGi32::lit("2"),
+        );
+        assert_eq!(matrices.root_motion_delta(), FGVec3::lit("4", "0", "0"));
+    }
+
+    #[test]
+    fn root_motion_translation_is_removed_from_published_pose() {
+        let names = ["root".into(), "hand".into()];
+        let parents = [None, Some(0)];
+        let mut root = FixedMat4::IDENTITY;
+        root.translate(FGVec3::lit("3", "4", "5"));
+        let mut hand = FixedMat4::IDENTITY;
+        hand.translate(FGVec3::lit("1", "2", "0"));
+        let mut matrices = FighterBoneMatrices::default();
+        let frame = crate::fighter::animation::FighterAnimationFrame::new(AnimKind::Wait, false);
+
+        matrices.set_pose_with_frame(
+            frame,
+            Some(0),
+            Some(FGVec3::lit("3", "4", "5")),
+            FGVec3::ZERO,
+            None,
+            AnimKind::Wait,
+            &names,
+            &parents,
+            &[root, hand],
+            FGi32::ONE,
+        );
+
+        assert_eq!(matrices.root_motion_delta(), FGVec3::ZERO);
+        assert_eq!(matrices.local(0).unwrap().get_translation(), FGVec3::ZERO);
+        assert_eq!(matrices.get_current("root").unwrap().get_translation(), FGVec3::ZERO);
+        assert_eq!(
+            matrices.get_current("hand").unwrap().get_translation(),
+            FGVec3::lit("1", "2", "0")
+        );
+    }
+
+    #[test]
+    fn every_animation_extracts_root_translation_and_retains_its_position() {
+        let names = ["root".into(), "hand".into()];
+        let parents = [None, Some(0)];
+        let mut root = FixedMat4::IDENTITY;
+        root.translate(FGVec3::lit("3", "4", "5"));
+        let mut hand = FixedMat4::IDENTITY;
+        hand.translate(FGVec3::lit("1", "2", "0"));
+        let mut matrices = FighterBoneMatrices::default();
+        let frame = crate::fighter::animation::FighterAnimationFrame::new(
+            AnimKind::LedgeWait,
+            true,
+        );
+
+        matrices.set_pose_with_frame(
+            frame,
+            Some(0),
+            Some(FGVec3::lit("3", "4", "5")),
+            FGVec3::ZERO,
+            None,
+            AnimKind::LedgeWait,
+            &names,
+            &parents,
+            &[root, hand],
+            FGi32::ONE,
+        );
+
+        assert_eq!(matrices.root_motion_delta(), FGVec3::ZERO);
+        assert_eq!(
+            matrices.root_motion_position(),
+            Some(FGVec3::lit("3", "4", "5"))
+        );
+        assert_eq!(matrices.local(0).unwrap().get_translation(), FGVec3::ZERO);
+        assert_eq!(
+            matrices.get_current("root").unwrap().get_translation(),
+            FGVec3::ZERO
+        );
+        assert_eq!(
+            matrices.get_current("hand").unwrap().get_translation(),
+            FGVec3::lit("1", "2", "0")
+        );
+
+        root.translate(FGVec3::lit("6", "4", "5"));
+        matrices.set_pose_with_frame(
+            crate::fighter::animation::FighterAnimationFrame { frame: 1, ..frame },
+            Some(0),
+            Some(FGVec3::lit("6", "4", "5")),
+            FGVec3::ZERO,
+            None,
+            AnimKind::LedgeWait,
+            &names,
+            &parents,
+            &[root, hand],
+            FGi32::ONE,
+        );
+        assert_eq!(matrices.root_motion_delta(), FGVec3::lit("3", "0", "0"));
+        assert_eq!(
+            matrices.get_current("root").unwrap().get_translation(),
+            FGVec3::ZERO
+        );
+    }
+
+    #[test]
+    fn repeating_root_motion_preserves_cycle_displacement_at_every_wrap() {
+        let names = ["root".into()];
+        let parents = [None];
+        let pose = |x| FixedMat4::IDENTITY.with_translation(FGVec3::lit(x, "0", "0"));
+        let mut matrices = FighterBoneMatrices::default();
+        let frame = |frame| crate::fighter::animation::FighterAnimationFrame {
+            kind: AnimKind::Wait,
+            frame,
+            repeat: true,
+        };
+
+        for (frame_number, x, expected_delta) in [
+            (0, "0", FGVec3::ZERO),
+            (1, "1", FGVec3::lit("1", "0", "0")),
+            (2, "0", FGVec3::lit("1", "0", "0")),
+            (3, "1", FGVec3::lit("1", "0", "0")),
+            (4, "0", FGVec3::lit("1", "0", "0")),
+        ] {
+            matrices.set_pose_with_frame(
+                frame(frame_number),
+                Some(0),
+                Some(FGVec3::lit(x, "0", "0")),
+                FGVec3::lit("2", "0", "0"),
+                Some(2),
+                AnimKind::Wait,
+                &names,
+                &parents,
+                &[pose(x)],
+                FGi32::ONE,
+            );
+            assert_eq!(matrices.root_motion_delta(), expected_delta);
+        }
+    }
+
     #[test]
     fn fixed_matrix_transforms_points() {
         let transform = FixedMat4 {

src/fighter/baked_animation/runtime.rs

@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 
 use bevy::prelude::*;
+use bevy_ggrs::Rollback;
 use serde::{Deserialize, Serialize};
 
 use super::BAKED_ANIMATION_FPS;
@@ -14,11 +15,15 @@ use crate::{
     },
     math::fixed_transform::FixedMat4,
     math::int::FGi32,
+    math::vec3::FGVec3,
 };
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct BakedAnimationClip {
     pub frames: Vec<Vec<FixedMat4>>,
+    /// Unscaled model-space position of the configured root-motion bone at
+    /// each baked frame.
+    pub root_positions: Vec<FGVec3>,
 }
 
 #[derive(Asset, bevy::reflect::TypePath, Clone, Debug, Serialize, Deserialize)]
@@ -27,11 +32,22 @@ pub struct BakedFighterAnimations {
     pub frame_rate: u32,
     pub bone_names: Vec<String>,
     pub parents: Vec<Option<usize>>,
+    pub(super) root_bone_index: usize,
     pub(super) clips: Vec<BakedAnimationClip>,
     pub(super) clip_indices: HashMap<AnimKind, usize>,
 }
 
 impl BakedFighterAnimations {
+    fn sample_index(&self, frame: &FighterAnimationFrame) -> Option<usize> {
+        let frames = &self.clip(frame.kind)?.frames;
+        let frame_index = if frame.repeat {
+            let loop_frame_count = frames.len().saturating_sub(1).max(1) as u32;
+            frame.frame % loop_frame_count
+        } else {
+            frame.frame
+        };
+        Some((frame_index as usize).min(frames.len().saturating_sub(1)))
+    }
     pub fn contains_bone(&self, bone: &str) -> bool {
         self.bone_names.iter().any(|name| name == bone)
     }
@@ -40,29 +56,67 @@ impl BakedFighterAnimations {
         self.bone_names.iter().all(|name| names.insert(name))
     }
     pub fn sample_pose(&self, frame: &FighterAnimationFrame) -> Option<&[FixedMat4]> {
-        let frames = &self.clip(frame.kind)?.frames;
+        let clip = self.clip(frame.kind)?;
-        let frame_index = if frame.repeat {
+        clip.frames.get(self.sample_index(frame)?).map(Vec::as_slice)
-            let loop_frame_count = frames.len().saturating_sub(1).max(1) as u32;
+    }
-            frame.frame % loop_frame_count
+    pub fn sample_root_position(
-        } else {
+        &self,
-            frame.frame
+        frame: &FighterAnimationFrame,
-        };
+        model_scale: FGi32,
-        frames
+    ) -> Option<FGVec3> {
-            .get(frame_index as usize)
+        let clip = self.clip(frame.kind)?;
-            .or_else(|| frames.last())
+        let position = *clip.root_positions.get(self.sample_index(frame)?)?;
-            .map(Vec::as_slice)
+        Some(position * model_scale)
+    }
+    pub fn initial_root_position(&self, kind: AnimKind, model_scale: FGi32) -> Option<FGVec3> {
+        self.sample_root_position(&FighterAnimationFrame::new(kind, false), model_scale)
     }
     pub fn frame_count(&self, kind: AnimKind) -> Option<u32> {
         self.clip(kind).map(|clip| clip.frames.len() as u32)
     }
+    pub fn root_motion_cycle_delta(
+        &self,
+        kind: AnimKind,
+        model_scale: FGi32,
+    ) -> Option<FGVec3> {
+        let clip = self.clip(kind)?;
+        Some((*clip.root_positions.last()? - *clip.root_positions.first()?) * model_scale)
+    }
+    /// Samples one bone in model space without depending on the runtime's
+    /// previous-frame buffers. Tooling uses this when the user scrubs between
+    /// unrelated frames.
+    pub fn sample_bone_model_transform(
+        &self,
+        frame: &FighterAnimationFrame,
+        bone: &str,
+        model_scale: FGi32,
+    ) -> Option<FixedMat4> {
+        let local = self.sample_pose(frame)?;
+        let index = self.bone_names.iter().position(|name| name == bone)?;
+        let mut model = vec![None; local.len()];
+        resolve_model_transform(index, &self.parents, local, &mut model).ok()?;
+        let scale = FixedMat4 {
+            cols: [
+                [model_scale, FGi32::ZERO, FGi32::ZERO, FGi32::ZERO],
+                [FGi32::ZERO, model_scale, FGi32::ZERO, FGi32::ZERO],
+                [FGi32::ZERO, FGi32::ZERO, model_scale, FGi32::ZERO],
+                [FGi32::ZERO, FGi32::ZERO, FGi32::ZERO, FGi32::ONE],
+            ],
+        };
+        Some(scale.mul(model[index]?))
+    }
     pub(super) fn clip(&self, kind: AnimKind) -> Option<&BakedAnimationClip> {
         self.clip_indices
             .get(&kind)
             .and_then(|index| self.clips.get(*index))
     }
+    pub fn get_animation_duration(&self, kind: AnimKind) -> Option<usize> {
+        self.clip(kind).map(|clip| clip.frames.len())
+    }
 }
 
-#[derive(Component, Clone, Debug, Default)]
+#[derive(Component, Clone, Debug, Default, Hash)]
+#[require(Rollback)]
 pub struct FighterBoneMatrices {
     bone_names: Vec<String>,
     parents: Vec<Option<usize>>,
@@ -71,12 +125,45 @@ pub struct FighterBoneMatrices {
     local_matrices: Vec<FixedMat4>,
     previous_local_matrices: Vec<FixedMat4>,
     model_matrices: Vec<Option<FixedMat4>>,
+    presentation_kind: Option<AnimKind>,
+    previous_animation_frame: Option<FighterAnimationFrame>,
+    root_motion_position: Option<FGVec3>,
+    /// The raw, scaled model-space root translation used as the baseline for
+    /// root-motion extraction.  This is kept separately because the published
+    /// pose has the root translation removed.
+    previous_root_motion_translation: Option<FGVec3>,
+    root_motion_delta: crate::math::vec3::FGVec3,
 }
 
 #[derive(Component, Clone, Debug, Default)]
 pub struct FighterBoneIndexMap(pub HashMap<String, usize>);
 
 impl FighterBoneMatrices {
+    /// Samples a baked pose for a preview or other non-gameplay caller.
+    pub fn sample_baked_pose(
+        &mut self,
+        baked: &BakedFighterAnimations,
+        frame: &FighterAnimationFrame,
+        model_scale: FGi32,
+    ) -> bool {
+        let Some(pose) = baked.sample_pose(frame) else {
+            return false;
+        };
+        self.set_pose_with_frame(
+            *frame,
+            Some(baked.root_bone_index),
+            baked.sample_root_position(frame, model_scale),
+            FGVec3::ZERO,
+            None,
+            frame.kind,
+            &baked.bone_names,
+            &baked.parents,
+            pose,
+            model_scale,
+        );
+        true
+    }
+
     #[cfg(test)]
     pub(super) fn buffer_capacities(&self) -> [usize; 5] {
         [
@@ -88,6 +175,12 @@ impl FighterBoneMatrices {
         ]
     }
 
+    pub fn get_by_idx(&self, index: usize) -> Option<(FixedMat4, FixedMat4)> {
+        Some((
+            *self.previous_frame_matrices.get(index)?,
+            *self.matrices.get(index)?,
+        ))
+    }
     pub fn get(&self, bone: &str) -> Option<(FixedMat4, FixedMat4)> {
         let index = self.bone_names.iter().position(|name| name == bone)?;
         Some((
@@ -108,6 +201,16 @@ impl FighterBoneMatrices {
     pub fn get_current_index(&self, index: usize) -> Option<FixedMat4> {
         self.matrices.get(index).copied()
     }
+    /// Translation of the configured root-motion bone since the previous
+    /// simulation animation frame, in scaled model-space units.
+    pub fn root_motion_delta(&self) -> FGVec3 {
+        self.root_motion_delta
+    }
+    /// Current raw, scaled model-space position of the configured root-motion
+    /// bone. The published skeleton has this translation removed.
+    pub fn root_motion_position(&self) -> Option<FGVec3> {
+        self.root_motion_position
+    }
     pub fn iter(&self) -> impl Iterator<Item = (&str, FixedMat4)> {
         self.bone_names
             .iter()
@@ -130,12 +233,117 @@ impl FighterBoneMatrices {
             .unwrap_or(current);
         Some(interpolate_transform(previous, current, overstep_fraction))
     }
+    #[cfg(test)]
     pub(super) fn set_pose(
         &mut self,
+        kind: AnimKind,
         bone_names: &[String],
         parents: &[Option<usize>],
         local: &[FixedMat4],
         model_scale: FGi32,
+    ) {
+        self.set_pose_with_frame(
+            FighterAnimationFrame::new(kind, false),
+            None,
+            None,
+            FGVec3::ZERO,
+            None,
+            kind,
+            bone_names,
+            parents,
+            local,
+            model_scale,
+        );
+    }
+    pub(super) fn set_pose_with_frame(
+        &mut self,
+        animation_frame: FighterAnimationFrame,
+        root_bone_index: Option<usize>,
+        root_motion_position: Option<FGVec3>,
+        root_motion_cycle_delta: FGVec3,
+        root_motion_loop_frame_count: Option<u32>,
+        kind: AnimKind,
+        bone_names: &[String],
+        parents: &[Option<usize>],
+        local: &[FixedMat4],
+        model_scale: FGi32,
+    ) {
+        self.sample_pose(
+            animation_frame,
+            root_bone_index,
+            root_motion_position,
+            root_motion_cycle_delta,
+            root_motion_loop_frame_count,
+            kind,
+            bone_names,
+            parents,
+            local,
+            model_scale,
+            true,
+        );
+    }
+    #[cfg(test)]
+    pub(super) fn resample_pose(
+        &mut self,
+        kind: AnimKind,
+        bone_names: &[String],
+        parents: &[Option<usize>],
+        local: &[FixedMat4],
+        model_scale: FGi32,
+    ) {
+        self.resample_pose_with_frame(
+            FighterAnimationFrame::new(kind, false),
+            None,
+            None,
+            FGVec3::ZERO,
+            None,
+            kind,
+            bone_names,
+            parents,
+            local,
+            model_scale,
+        );
+    }
+    pub(super) fn resample_pose_with_frame(
+        &mut self,
+        animation_frame: FighterAnimationFrame,
+        root_bone_index: Option<usize>,
+        root_motion_position: Option<FGVec3>,
+        _root_motion_cycle_delta: FGVec3,
+        _root_motion_loop_frame_count: Option<u32>,
+        kind: AnimKind,
+        bone_names: &[String],
+        parents: &[Option<usize>],
+        local: &[FixedMat4],
+        model_scale: FGi32,
+    ) {
+        self.sample_pose(
+            animation_frame,
+            root_bone_index,
+            root_motion_position,
+            FGVec3::ZERO,
+            None,
+            kind,
+            bone_names,
+            parents,
+            local,
+            model_scale,
+            false,
+        );
+    }
+    fn sample_pose(
+        &mut self,
+        animation_frame: FighterAnimationFrame,
+        root_index: Option<usize>,
+        raw_root_motion_translation: Option<FGVec3>,
+        root_motion_cycle_delta: FGVec3,
+        root_motion_loop_frame_count: Option<u32>,
+        kind: AnimKind,
+        bone_names: &[String],
+        parents: &[Option<usize>],
+        local: &[FixedMat4],
+        model_scale: FGi32,
+        advance_history: bool,
     ) {
         assert_eq!(
             bone_names.len(),
@@ -147,6 +355,7 @@ impl FighterBoneMatrices {
             parents.len(),
             "baked bone parents do not match names"
         );
+        let animation_changed = self.presentation_kind != Some(kind);
         if self.bone_names.is_empty() {
             self.bone_names.extend_from_slice(bone_names);
             self.parents.extend_from_slice(parents);
@@ -159,16 +368,13 @@ impl FighterBoneMatrices {
         self.local_matrices.reserve(local.len());
         self.previous_local_matrices.reserve(local.len());
         self.model_matrices.reserve(local.len());
-        std::mem::swap(&mut self.matrices, &mut self.previous_frame_matrices);
+        if advance_history {
-        std::mem::swap(&mut self.local_matrices, &mut self.previous_local_matrices);
+            std::mem::swap(&mut self.matrices, &mut self.previous_frame_matrices);
+            std::mem::swap(&mut self.local_matrices, &mut self.previous_local_matrices);
+        }
         self.local_matrices.clear();
         self.local_matrices.extend_from_slice(local);
-        self.model_matrices.resize(local.len(), None);
+
-        self.model_matrices.fill(None);
-        for index in 0..local.len() {
-            resolve_model_transform(index, parents, local, &mut self.model_matrices)
-                .expect("baked bone hierarchy should be valid");
-        }
         let model_scale = FixedMat4 {
             cols: [
                 [model_scale, FGi32::ZERO, FGi32::ZERO, FGi32::ZERO],
@@ -177,12 +383,60 @@ impl FighterBoneMatrices {
                 [FGi32::ZERO, FGi32::ZERO, FGi32::ZERO, FGi32::ONE],
             ],
         };
+        // Gameplay always owns root displacement. Keep rotation and scale in
+        // the pose while removing the configured root bone's translation.
+        if let Some(root_index) = root_index {
+            self.local_matrices[root_index].translate(FGVec3::ZERO);
+        }
+        self.model_matrices.resize(local.len(), None);
+        self.model_matrices.fill(None);
+        for index in 0..local.len() {
+            resolve_model_transform(index, parents, &self.local_matrices, &mut self.model_matrices)
+                .expect("baked bone hierarchy should be valid");
+        }
         self.matrices.clear();
         self.matrices.extend(
             self.model_matrices.iter().map(|matrix| {
                 model_scale.mul(matrix.expect("baked bone hierarchy should be valid"))
             }),
         );
+        self.root_motion_delta = if advance_history
+            && !animation_changed
+            && self.previous_animation_frame.is_some()
+            && let (Some(current), Some(previous)) = (
+                raw_root_motion_translation,
+                self.previous_root_motion_translation,
+            )
+        {
+            let mut delta = current - previous;
+            if animation_frame.repeat
+                && self.previous_animation_frame.is_some_and(|previous| {
+                    previous.kind == animation_frame.kind
+                        && previous.frame.saturating_add(1) == animation_frame.frame
+                })
+                && root_motion_loop_frame_count.is_some_and(|loop_frame_count| {
+                    loop_frame_count > 0 && animation_frame.frame % loop_frame_count == 0
+                })
+            {
+                delta = delta + root_motion_cycle_delta;
+            }
+            delta
+        } else {
+            FGVec3::ZERO
+        };
+        self.root_motion_position = raw_root_motion_translation;
+        self.previous_root_motion_translation = raw_root_motion_translation;
+        if advance_history {
+            self.previous_animation_frame = Some(animation_frame);
+        }
+        // A state transition is a discontinuity, not an animation frame to
+        // interpolate from the previous clip.  Keep the presentation pose at
+        // the new clip's first/current frame immediately.
+        if animation_changed {
+            self.previous_local_matrices
+                .clone_from(&self.local_matrices);
+        }
+        self.presentation_kind = Some(kind);
     }
 }
 
@@ -198,38 +452,115 @@ pub fn update_fighter_bone_matrices(
     manifests: Res<Assets<FighterManifest>>,
 ) {
     for (frame, animations, fighter, mut matrices, mut bone_indices) in &mut fighters {
-        let baked = baked_assets
+        sample_fighter_bone_matrices(
-            .get(&animations.baked)
+            frame,
-            .expect("fighter baked animation asset should be loaded before the match starts");
+            animations,
-        assert_eq!(
+            fighter,
-            baked.frame_rate, BAKED_ANIMATION_FPS,
+            &mut matrices,
-            "fighter baked animation rate does not match the simulation rate"
+            &mut bone_indices,
+            &baked_assets,
+            &manifests,
+            true,
         );
-        let pose = baked
+    }
-            .sample_pose(frame)
+}
-            .expect("fighter animation frame should select a baked pose");
+
-        let manifest = manifests
+/// Resamples the current pose after collision-driven state transitions without
-            .get(&fighter.manifest)
+/// advancing the previous-frame pose used for swept gameplay volumes.
-            .expect("fighter manifest should be loaded before the match starts");
+pub fn resample_fighter_bone_matrices(
-        matrices.set_pose(
+    mut fighters: Query<(
+        &FighterAnimationFrame,
+        &FighterAnimations,
+        &Fighter,
+        &mut FighterBoneMatrices,
+        &mut FighterBoneIndexMap,
+    )>,
+    baked_assets: Res<Assets<BakedFighterAnimations>>,
+    manifests: Res<Assets<FighterManifest>>,
+) {
+    for (frame, animations, fighter, mut matrices, mut bone_indices) in &mut fighters {
+        sample_fighter_bone_matrices(
+            frame,
+            animations,
+            fighter,
+            &mut matrices,
+            &mut bone_indices,
+            &baked_assets,
+            &manifests,
+            false,
+        );
+    }
+}
+
+fn sample_fighter_bone_matrices(
+    frame: &FighterAnimationFrame,
+    animations: &FighterAnimations,
+    fighter: &Fighter,
+    matrices: &mut FighterBoneMatrices,
+    bone_indices: &mut FighterBoneIndexMap,
+    baked_assets: &Assets<BakedFighterAnimations>,
+    manifests: &Assets<FighterManifest>,
+    advance_history: bool,
+) {
+    let baked = baked_assets
+        .get(&animations.baked)
+        .expect("fighter baked animation asset should be loaded before the match starts");
+    assert_eq!(
+        baked.frame_rate, BAKED_ANIMATION_FPS,
+        "fighter baked animation rate does not match the simulation rate"
+    );
+    let pose = baked
+        .sample_pose(frame)
+        .expect("fighter animation frame should select a baked pose");
+    let manifest = manifests
+        .get(&fighter.manifest)
+        .expect("fighter manifest should be loaded before the match starts");
+    let root_motion_position = baked.sample_root_position(frame, manifest.model_scale);
+    let root_motion_cycle_delta = baked
+        .root_motion_cycle_delta(frame.kind, manifest.model_scale)
+        .unwrap_or(FGVec3::ZERO);
+    let root_motion_loop_frame_count = baked
+        .frame_count(frame.kind)
+        .map(|count| count.saturating_sub(1).max(1));
+    if advance_history {
+        matrices.set_pose_with_frame(
+            *frame,
+            Some(baked.root_bone_index),
+            root_motion_position,
+            root_motion_cycle_delta,
+            root_motion_loop_frame_count,
+            frame.kind,
             &baked.bone_names,
             &baked.parents,
             pose,
             manifest.model_scale,
         );
-        if bone_indices.0.is_empty() {
+    } else {
-            bone_indices.0.extend(
+        matrices.resample_pose_with_frame(
-                baked
+            *frame,
-                    .bone_names
+            Some(baked.root_bone_index),
-                    .iter()
+            root_motion_position,
-                    .enumerate()
+            FGVec3::ZERO,
-                    .map(|(index, name)| (name.clone(), index)),
+            None,
-            );
+            frame.kind,
-        }
+            &baked.bone_names,
+            &baked.parents,
+            pose,
+            manifest.model_scale,
+        );
+    }
+    if bone_indices.0.is_empty() {
+        bone_indices.0.extend(
+            baked
+                .bone_names
+                .iter()
+                .enumerate()
+                .map(|(index, name)| (name.clone(), index)),
+        );
     }
 }
 
-fn resolve_model_transform(
+pub(super) fn resolve_model_transform(
     index: usize,
     parents: &[Option<usize>],
     local: &[FixedMat4],

src/fighter/baked_animation/visual_binding.rs

@@ -92,9 +92,12 @@ pub(super) fn bind_fighter_visual_bones(
 pub(super) fn apply_baked_fighter_visual_pose(
     mut nodes: Query<(&mut Transform, &BakedFighterBone)>,
     fighters: Query<&FighterBoneMatrices>,
-    timing: Res<GgrsFrameTiming>,
+    timing: Option<Res<GgrsFrameTiming>>,
 ) {
-    let overstep_fraction = timing.overstep_fraction();
+    let overstep_fraction = timing
+        .as_deref()
+        .map(GgrsFrameTiming::overstep_fraction)
+        .unwrap_or(0.0);
     for (mut transform, bone) in &mut nodes {
         let Ok(matrices) = fighters.get(bone.fighter) else {
             continue;

src/fighter/blast_zones.rs

@@ -0,0 +1,36 @@
+//! Various interactions with the blast zones
+
+use bevy::prelude::*;
+
+use crate::{fighter::{FighterPendingRespawn, FighterTranslation, state::FighterState}, match_loading::MatchConfig, stage::manifest::{StageManifest, StageManifestRegistry}};
+
+pub fn apply_blast_zones(
+    stage_registry: Res<StageManifestRegistry>,
+    stage_manifests: Res<Assets<StageManifest>>,
+    match_config: Res<MatchConfig>,
+    fighters: Query<(&FighterTranslation, &mut FighterPendingRespawn, &FighterState)>
+) {
+    let Some(stage_manifest_handle) = stage_registry.get(match_config.stage) else {
+        return;
+    };
+
+    let Some(stage_manifest) = stage_manifests.get(&stage_manifest_handle) else {
+        return;
+    };
+
+    for (translation, mut pending_respawn, state) in fighters {
+        let is_off_the_left = translation.x < stage_manifest.blast_zone_top_left.x;
+        let is_off_the_right = translation.x > stage_manifest.blast_zone_bottom_right.x;
+        let is_off_the_top = translation.y > stage_manifest.blast_zone_top_left.y;
+        let is_off_the_bottom = translation.y < stage_manifest.blast_zone_bottom_right.y;
+        
+        if is_off_the_left || is_off_the_bottom || is_off_the_right {
+            pending_respawn.0 = true;
+        } else if is_off_the_top {
+            let is_in_hitstun = matches!(state, FighterState::Hitstun(..));
+            if is_in_hitstun {
+                pending_respawn.0 = true;
+            }
+        }
+    }
+}

src/fighter/collision.rs

@@ -1,10 +1,17 @@
 //! Resolving an integrated fighter position against the stage.
 
-use crate::fighter::ecb::FighterPreviousECB;
+use crate::fighter::ecb::{self as ecb_module, FighterDesiredECB};
-use crate::fighter::{FighterECB, FighterPreviousTranslation, FighterTranslation};
+use crate::fighter::{FighterPreviousTranslation, FighterTranslation};
+use crate::fighter::FighterVelocity;
+#[cfg(test)]
+use crate::fighter::{FighterECB, ecb::FighterPreviousECB};
+use crate::math::int::FGi32;
+use crate::math::rect::FGRect;
 use crate::math::segment::FGSegment2d;
 use crate::math::vec::FGVec2;
-use crate::stage::line::{StageCollision, StageLineID};
+use crate::stage::line::{
+    StageCollision, StageLineID, StagePolyLineSegmentType, StagePolyType, StageVertexID,
+};
 /*
 pub fn collide_fighter_with_scene(
     fighters: Query<(&FighterECB, &mut FighterVelocity, &mut FighterTranslation)>,
@@ -35,44 +42,848 @@ pub fn collide_fighter_with_scene(
 pub struct AirCollisionWithStageResult {
     pub line_id: StageLineID,
     pub hit_position: FGVec2,
+    /// Fighter origin at the collision substep. The ECB remains local to this
+    /// origin; callers must not rebase the ECB by the frame-sized movement.
+    pub resolved_translation: FGVec2,
     pub hit_normal: FGVec2,
 }
 
-pub fn air_collide_with_stage(
+#[derive(Clone, Copy, Debug, Default)]
+pub struct AirCollisionOptions {
+    /// Allow downward input to disable collision with pass-through platforms.
+    pub can_pass_through_soft_platforms: bool,
+    /// Treat an upward crossing of a pass-through platform by the ECB bottom as a landing.
+    pub land_on_soft_platforms_from_below: bool,
+}
+
+#[cfg(test)]
+fn air_collide_with_stage(
     prev_translation: &FighterPreviousTranslation,
     translation: &FighterTranslation,
     prev_ecb: &FighterPreviousECB,
     ecb: &FighterECB,
     stage_collision: &StageCollision,
+    ignored_polys: &[usize],
+    options: AirCollisionOptions,
 ) -> Option<AirCollisionWithStageResult> {
-    let ray_segment = FGSegment2d::new(
+    let mut translation = *translation;
-        prev_translation.0 + prev_ecb.get_bottom_point(),
+    let mut velocity = FighterVelocity::default();
-        translation.0 + ecb.get_bottom_point(),
+    air_collide_with_stage_substepped(
-    );
+        prev_translation,
+        &mut translation,
+        &mut velocity,
+        &mut ecb_module::FighterECB {
+            top: prev_ecb.top,
+            bottom: prev_ecb.bottom,
+            left: prev_ecb.left,
+            right: prev_ecb.right,
+        },
+        &FighterDesiredECB::from(*ecb),
+        stage_collision,
+        ignored_polys,
+        options,
+    )
+}
+
+/// Sweeps movement and ECB shape changes together.
+pub(crate) fn collision_step_count(max_change: FGi32) -> u32 {
+    let six = FGi32::lit("6.0");
+    if max_change <= six {
+        return 1;
+    }
+
+    let mut quotient = 0;
+    let mut remainder = max_change;
+    while remainder >= six {
+        quotient += 1;
+        remainder -= six;
+    }
+    quotient + 1
+}
+
+pub fn air_collide_with_stage_substepped(
+    prev_translation: &FighterPreviousTranslation,
+    translation: &mut FighterTranslation,
+    velocity: &mut FighterVelocity,
+    ecb: &mut crate::fighter::FighterECB,
+    desired: &FighterDesiredECB,
+    stage_collision: &StageCollision,
+    ignored_polys: &[usize],
+    options: AirCollisionOptions,
+) -> Option<AirCollisionWithStageResult> {
+    let requested_translation = translation.0;
+    let movement = requested_translation - prev_translation.0;
+    let mut largest_change = movement.x.abs().max(movement.y.abs());
+    largest_change = largest_change.max(ecb_module::ecb_max_delta(ecb, desired));
+    let steps = collision_step_count(largest_change);
+
+    let step_count = FGi32::from_num(steps);
+    let movement_per_step = movement / step_count;
+    let mut current_position = prev_translation.0;
+    let mut current_ecb = *ecb;
+    let mut collision_offset = FGVec2::ZERO;
+
+    for step in 0..steps {
+        let previous_position = current_position;
+        let previous_ecb = current_ecb;
+        let remaining_steps = FGi32::from_num(steps - step);
+        ecb_module::interpolate_ecb(&mut current_ecb, *desired, FGi32::ONE / remaining_steps);
+        current_position = if step + 1 == steps {
+            // Fixed-point division may truncate. Always make the final
+            // substep land exactly on the requested frame endpoint.
+            requested_translation + collision_offset
+        } else {
+            prev_translation.0
+                + movement_per_step * FGi32::from_num(step + 1)
+                + collision_offset
+        };
+
+        let lower_edges = [
+            (
+                previous_ecb.bottom,
+                previous_ecb.left,
+                current_ecb.bottom,
+                current_ecb.left,
+            ),
+            (
+                previous_ecb.bottom,
+                previous_ecb.right,
+                current_ecb.bottom,
+                current_ecb.right,
+            ),
+        ];
+        if let Some(result) = sweep_edges(
+            stage_collision,
+            previous_position,
+            current_position,
+            &lower_edges,
+            StagePolyLineSegmentType::Floor,
+            ignored_polys,
+            options.can_pass_through_soft_platforms,
+        ) {
+            *ecb = current_ecb;
+            translation.0 = current_position + result.correction;
+            velocity.0 -= velocity.0.project_onto_normalized(result.hit_normal);
+            let bottom_contact = translation.0 + current_ecb.bottom;
+            return Some(AirCollisionWithStageResult {
+                line_id: result.line_id,
+                hit_position: bottom_contact,
+                resolved_translation: translation.0,
+                hit_normal: result.hit_normal,
+            });
+        }
+
+        let upper_edges = [
+            (
+                previous_ecb.top,
+                previous_ecb.left,
+                current_ecb.top,
+                current_ecb.left,
+            ),
+            (
+                previous_ecb.top,
+                previous_ecb.right,
+                current_ecb.top,
+                current_ecb.right,
+            ),
+        ];
+        if let Some(contact) = sweep_edges(
+            stage_collision,
+            previous_position,
+            current_position,
+            &upper_edges,
+            StagePolyLineSegmentType::Ceiling,
+            ignored_polys,
+            true,
+        ) {
+            current_position += contact.correction;
+            collision_offset += contact.correction;
+            velocity.0 -= velocity.0.project_onto_normalized(contact.hit_normal);
+        }
+
+        if options.land_on_soft_platforms_from_below
+            && let Some(result) = sweep_bottom_point_through_platforms(
+                stage_collision,
+                previous_position + previous_ecb.bottom,
+                current_position + current_ecb.bottom,
+                ignored_polys,
+            )
+        {
+            *ecb = current_ecb;
+            translation.0 = current_position + result.correction;
+            velocity.0 -= velocity.0.project_onto_normalized(result.hit_normal);
+            let bottom_contact = translation.0 + current_ecb.bottom;
+            return Some(AirCollisionWithStageResult {
+                line_id: result.line_id,
+                hit_position: bottom_contact,
+                resolved_translation: translation.0,
+                hit_normal: result.hit_normal,
+            });
+        }
+
+        let side_edges = [
+            (
+                previous_ecb.bottom,
+                previous_ecb.right,
+                current_ecb.bottom,
+                current_ecb.right,
+            ),
+            (
+                previous_ecb.right,
+                previous_ecb.top,
+                current_ecb.right,
+                current_ecb.top,
+            ),
+            (
+                previous_ecb.top,
+                previous_ecb.left,
+                current_ecb.top,
+                current_ecb.left,
+            ),
+            (
+                previous_ecb.left,
+                previous_ecb.bottom,
+                current_ecb.left,
+                current_ecb.bottom,
+            ),
+        ];
+        if let Some(contact) = sweep_edges(
+            stage_collision,
+            previous_position,
+            current_position,
+            &side_edges,
+            StagePolyLineSegmentType::Wall,
+            ignored_polys,
+            true,
+        ) {
+            current_position += contact.correction;
+            collision_offset += contact.correction;
+            velocity.0 -= velocity.0.project_onto_normalized(contact.hit_normal);
+        }
+    }
+
+    *ecb = current_ecb;
+    translation.0 = current_position;
+    None
+}
+
+struct PointSweepResult {
+    line_id: StageLineID,
+    hit_normal: FGVec2,
+    correction: FGVec2,
+}
+
+fn sweep_bottom_point_through_platforms(
+    stage_collision: &StageCollision,
+    previous_bottom: FGVec2,
+    current_bottom: FGVec2,
+    ignored_polys: &[usize],
+) -> Option<PointSweepResult> {
+    let bottom_sweep = FGSegment2d::new(previous_bottom, current_bottom);
 
     stage_collision
         .stage_polys
         .iter()
         .enumerate()
-        .filter_map(|(poly_idx, poly)| {
+        .filter(|(poly_idx, poly)| {
-            poly.intersect_ray(ray_segment).map(|intersect_result| {
+            !ignored_polys.contains(poly_idx) && matches!(poly.poly_type, StagePolyType::Platform)
-                (
+        })
-                    AirCollisionWithStageResult {
+        .flat_map(|(poly_idx, poly)| {
-                        line_id: {
+            poly.segments
-                            StageLineID {
+                .iter()
+                .enumerate()
+                .filter(|(_, segment)| {
+                    matches!(segment.segment_type, StagePolyLineSegmentType::Floor)
+                })
+                .filter_map(move |(segment_idx, segment)| {
+                    let previous_distance = segment
+                        .normal
+                        .dot(previous_bottom - segment.segment.point1());
+                    let current_distance = segment
+                        .normal
+                        .dot(current_bottom - segment.segment.point1());
+                    if previous_distance >= crate::math::int::FGWide::ZERO
+                        || current_distance < crate::math::int::FGWide::ZERO
+                    {
+                        return None;
+                    }
+
+                    let hit_position = segment.segment.segment_intersection(&bottom_sweep)?;
+                    Some((
+                        PointSweepResult {
+                            line_id: StageLineID {
                                 polygon: poly_idx,
-                                segment: intersect_result.segment_idx,
+                                segment: segment_idx,
-                            }
+                            },
+                            hit_normal: segment.normal,
+                            correction: hit_position - current_bottom,
                         },
-                        hit_position: intersect_result.position,
+                        hit_position.distance_squared(previous_bottom),
-                        hit_normal: intersect_result.normal,
+                    ))
-                    },
+                })
-                    intersect_result
+        })
-                        .position
+        .min_by_key(|(_, distance)| *distance)
-                        .distance_squared(ray_segment.point2()),
+        .map(|(result, _)| result)
-                )
+}
-            })
+
+fn sweep_edges(
+    stage_collision: &StageCollision,
+    previous_position: FGVec2,
+    current_position: FGVec2,
+    edges: &[(FGVec2, FGVec2, FGVec2, FGVec2)],
+    segment_type: StagePolyLineSegmentType,
+    ignored_polys: &[usize],
+    ignore_platforms: bool,
+) -> Option<PointSweepResult> {
+    stage_collision
+        .stage_polys
+        .iter()
+        .enumerate()
+        .filter(|(poly_idx, poly)| {
+            !ignored_polys.contains(poly_idx)
+                && !(ignore_platforms && matches!(poly.poly_type, StagePolyType::Platform))
+        })
+        .flat_map(|(poly_idx, poly)| {
+            poly.segments
+                .iter()
+                .enumerate()
+                .filter(move |(_, segment)| segment.segment_type == segment_type)
+                .filter_map(move |(segment_idx, segment)| {
+                    edges
+                        .iter()
+                        .filter_map(|(previous_a, previous_b, current_a, current_b)| {
+                            let previous_a = previous_position + *previous_a;
+                            let previous_b = previous_position + *previous_b;
+                            let current_a = current_position + *current_a;
+                            let current_b = current_position + *current_b;
+                            let previous_min = segment
+                                .normal
+                                .dot(previous_a - segment.segment.point1())
+                                .min(segment.normal.dot(previous_b - segment.segment.point1()));
+                            let current_a_distance =
+                                segment.normal.dot(current_a - segment.segment.point1());
+                            let current_b_distance =
+                                segment.normal.dot(current_b - segment.segment.point1());
+                            let current_min = current_a_distance.min(current_b_distance);
+                            if previous_min < crate::math::int::FGWide::ZERO
+                                || current_min > crate::math::int::FGWide::ZERO
+                            {
+                                return None;
+                            }
+
+                            let boundary = [
+                                FGSegment2d::new(previous_a, previous_b),
+                                FGSegment2d::new(previous_a, current_a),
+                                FGSegment2d::new(previous_b, current_b),
+                                FGSegment2d::new(current_a, current_b),
+                            ];
+                            let quad = [previous_a, previous_b, current_b, current_a];
+                            let position = boundary
+                                .iter()
+                                .filter_map(|edge| segment.segment.segment_intersection(edge))
+                                .max_by_key(|position| position.distance_squared(current_a))
+                                .or_else(|| {
+                                    [segment.segment.point1(), segment.segment.point2()]
+                                        .into_iter()
+                                        .find(|point| point_in_convex_quad(*point, quad))
+                                })?;
+                            let penetration = FGi32::from_num(-current_min);
+                            Some((position, segment.normal * penetration))
+                        })
+                        .max_by_key(|(position, _)| {
+                            position.distance_squared(segment.segment.point1())
+                        })
+                        .map(|(position, correction)| {
+                            (
+                                PointSweepResult {
+                                    line_id: StageLineID {
+                                        polygon: poly_idx,
+                                        segment: segment_idx,
+                                    },
+                                    hit_normal: segment.normal,
+                                    correction,
+                                },
+                                position.distance_squared(segment.segment.point2()),
+                            )
+                        })
+                })
         })
         .max_by(|(_, a), (_, b)| a.cmp(b))
         .map(|(result, _)| result)
 }
+
+fn point_in_convex_quad(point: FGVec2, quad: [FGVec2; 4]) -> bool {
+    let mut has_positive = false;
+    let mut has_negative = false;
+    for (a, b) in quad.into_iter().zip(quad.into_iter().cycle().skip(1)).take(4) {
+        let edge = b - a;
+        let offset = point - a;
+        let cross = crate::math::int::FGWide::from_num(edge.x)
+            * crate::math::int::FGWide::from_num(offset.y)
+            - crate::math::int::FGWide::from_num(edge.y)
+                * crate::math::int::FGWide::from_num(offset.x);
+        has_positive |= cross > crate::math::int::FGWide::ZERO;
+        has_negative |= cross < crate::math::int::FGWide::ZERO;
+        if has_positive && has_negative {
+            return false;
+        }
+    }
+    true
+}
+
+#[derive(Clone)]
+pub struct AirCollisionWithLedgeResult {
+    pub ledge: StageVertexID,
+}
+
+pub fn air_collide_with_ledges(
+    ledge_box: &FGRect,
+    stage_collision: &StageCollision,
+) -> Option<AirCollisionWithLedgeResult> {
+    stage_collision
+        .intersect_ledges(ledge_box)
+        .map(|result| AirCollisionWithLedgeResult {
+            ledge: result.vertex_id,
+        })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::fighter::ecb::{FighterECB, FighterPreviousECB};
+    use crate::stage::line::{StagePoly, StagePolyLineSegmentType, StagePolyType};
+
+    fn horizontal_platform(y: &str) -> StagePoly {
+        StagePoly::build(
+            StagePolyType::Platform,
+            &[
+                (FGVec2::lit("-2", y), StagePolyLineSegmentType::Floor),
+                (FGVec2::lit("2", y), StagePolyLineSegmentType::Floor),
+            ],
+        )
+    }
+
+    fn solid_floor() -> StagePoly {
+        StagePoly::build(
+            StagePolyType::Closed,
+            &[
+                (FGVec2::lit("-2", "0"), StagePolyLineSegmentType::Floor),
+                (FGVec2::lit("2", "0"), StagePolyLineSegmentType::Floor),
+                (FGVec2::lit("2", "-2"), StagePolyLineSegmentType::Wall),
+                (FGVec2::lit("-2", "-2"), StagePolyLineSegmentType::Wall),
+            ],
+        )
+    }
+
+    fn single_segment(
+        start: FGVec2,
+        end: FGVec2,
+        segment_type: StagePolyLineSegmentType,
+    ) -> StagePoly {
+        let segment = FGSegment2d::new(start, end);
+        StagePoly {
+            poly_type: StagePolyType::Closed,
+            segments: vec![crate::stage::line::StagePolyLineSegment {
+                segment,
+                normal: segment.left_normal(),
+                segment_type,
+            }],
+        }
+    }
+
+    #[test]
+    fn melee_step_count_adds_one_step_after_each_six_unit_block() {
+        assert_eq!(collision_step_count(FGi32::lit("6")), 1);
+        assert_eq!(collision_step_count(FGi32::lit("6.01")), 2);
+        assert_eq!(collision_step_count(FGi32::lit("12")), 3);
+        assert_eq!(collision_step_count(FGi32::lit("18")), 4);
+    }
+
+    #[test]
+    fn collision_result_keeps_ecb_local_to_resolved_origin() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![horizontal_platform("0")],
+            ..StageCollision::default()
+        };
+        let previous_translation = FighterPreviousTranslation(FGVec2::lit("0", "2"));
+        let mut translation = FighterTranslation(FGVec2::lit("0", "-1"));
+        let mut velocity = FighterVelocity(FGVec2::lit("0", "-3"));
+        let mut ecb = FighterECB {
+            top: FGVec2::lit("0", "2"),
+            bottom: FGVec2::lit("0", "-1"),
+            left: FGVec2::lit("-1", "0.5"),
+            right: FGVec2::lit("1", "0.5"),
+        };
+        let desired = FighterDesiredECB::from(ecb);
+        let collision = air_collide_with_stage_substepped(
+            &previous_translation,
+            &mut translation,
+            &mut velocity,
+            &mut ecb,
+            &desired,
+            &stage_collision,
+            &[],
+            Default::default(),
+        )
+        .expect("the floor should be hit");
+
+        assert_eq!(
+            collision.resolved_translation + ecb.bottom,
+            collision.hit_position
+        );
+        assert_eq!(velocity.0.y, FGi32::ZERO);
+    }
+
+    #[test]
+    fn airborne_side_point_resolves_wall_and_projects_velocity() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![single_segment(
+                FGVec2::lit("2", "2"),
+                FGVec2::lit("2", "-2"),
+                StagePolyLineSegmentType::Wall,
+            )],
+            ..StageCollision::default()
+        };
+        let previous = FighterPreviousTranslation(FGVec2::lit("4", "0"));
+        let mut translation = FighterTranslation(FGVec2::lit("0", "0"));
+        let mut velocity = FighterVelocity(FGVec2::lit("-4", "0"));
+        let mut ecb = FighterECB {
+            top: FGVec2::lit("0", "1"),
+            bottom: FGVec2::lit("0", "-1"),
+            left: FGVec2::lit("-1", "0"),
+            right: FGVec2::lit("1", "0"),
+        };
+        let desired = FighterDesiredECB::from(ecb);
+
+        assert!(air_collide_with_stage_substepped(
+            &previous,
+            &mut translation,
+            &mut velocity,
+            &mut ecb,
+            &desired,
+            &stage_collision,
+            &[],
+            Default::default(),
+        )
+        .is_none());
+        assert_eq!(translation.0, FGVec2::lit("3", "0"));
+        assert_eq!(velocity.0.x, FGi32::ZERO);
+    }
+
+    #[test]
+    fn stage_corner_cannot_pass_through_middle_of_diamond_edge() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![single_segment(
+                FGVec2::lit("2", "0.6"),
+                FGVec2::lit("2", "0.4"),
+                StagePolyLineSegmentType::Wall,
+            )],
+            ..StageCollision::default()
+        };
+        let previous = FighterPreviousTranslation(FGVec2::lit("4", "0"));
+        let mut translation = FighterTranslation(FGVec2::ZERO);
+        let mut velocity = FighterVelocity(FGVec2::lit("-4", "0"));
+        let mut ecb = FighterECB {
+            top: FGVec2::lit("0", "1"),
+            bottom: FGVec2::lit("0", "-1"),
+            left: FGVec2::lit("-1", "0"),
+            right: FGVec2::lit("1", "0"),
+        };
+        let desired = FighterDesiredECB::from(ecb);
+
+        assert!(air_collide_with_stage_substepped(
+            &previous,
+            &mut translation,
+            &mut velocity,
+            &mut ecb,
+            &desired,
+            &stage_collision,
+            &[],
+            Default::default(),
+        )
+        .is_none());
+        assert_eq!(translation.0.x, FGi32::lit("3"));
+        assert_eq!(velocity.0.x, FGi32::ZERO);
+    }
+
+    #[test]
+    fn airborne_top_point_resolves_ceiling_and_projects_velocity() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![single_segment(
+                FGVec2::lit("2", "2"),
+                FGVec2::lit("-2", "2"),
+                StagePolyLineSegmentType::Ceiling,
+            )],
+            ..StageCollision::default()
+        };
+        let previous = FighterPreviousTranslation(FGVec2::ZERO);
+        let mut translation = FighterTranslation(FGVec2::lit("0", "4"));
+        let mut velocity = FighterVelocity(FGVec2::lit("0", "4"));
+        let mut ecb = FighterECB {
+            top: FGVec2::lit("0", "1"),
+            bottom: FGVec2::lit("0", "-1"),
+            left: FGVec2::lit("-1", "0"),
+            right: FGVec2::lit("1", "0"),
+        };
+        let desired = FighterDesiredECB::from(ecb);
+
+        assert!(air_collide_with_stage_substepped(
+            &previous,
+            &mut translation,
+            &mut velocity,
+            &mut ecb,
+            &desired,
+            &stage_collision,
+            &[],
+            Default::default(),
+        )
+        .is_none());
+        assert_eq!(translation.0, FGVec2::lit("0", "1"));
+        assert_eq!(velocity.0.y, FGi32::ZERO);
+    }
+
+    #[test]
+    fn airborne_collision_skips_ignored_polygons() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![horizontal_platform("0"), horizontal_platform("1")],
+            ..StageCollision::default()
+        };
+        let previous_translation = FighterPreviousTranslation(FGVec2::lit("0", "2"));
+        let translation = FighterTranslation(FGVec2::lit("0", "-1"));
+        let previous_ecb = FighterPreviousECB {
+            bottom: FGVec2::ZERO,
+            top: FGVec2::ZERO,
+            left: FGVec2::ZERO,
+            right: FGVec2::ZERO,
+        };
+        let ecb = FighterECB {
+            bottom: FGVec2::ZERO,
+            top: FGVec2::ZERO,
+            left: FGVec2::ZERO,
+            right: FGVec2::ZERO,
+        };
+
+        let collision = air_collide_with_stage(
+            &previous_translation,
+            &translation,
+            &previous_ecb,
+            &ecb,
+            &stage_collision,
+            &[1],
+            Default::default(),
+        )
+        .expect("the non-ignored platform should still be collidable");
+
+        assert_eq!(collision.line_id.polygon, 0);
+        assert_eq!(collision.hit_position, FGVec2::lit("0", "0"));
+    }
+
+    #[test]
+    fn airborne_collision_skips_soft_platforms_while_passing_down() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![horizontal_platform("0")],
+            ..StageCollision::default()
+        };
+        let previous_translation = FighterPreviousTranslation(FGVec2::lit("0", "2"));
+        let translation = FighterTranslation(FGVec2::lit("0", "-1"));
+        let previous_ecb = FighterPreviousECB {
+            bottom: FGVec2::ZERO,
+            top: FGVec2::ZERO,
+            left: FGVec2::ZERO,
+            right: FGVec2::ZERO,
+        };
+        let ecb = FighterECB {
+            bottom: FGVec2::ZERO,
+            top: FGVec2::ZERO,
+            left: FGVec2::ZERO,
+            right: FGVec2::ZERO,
+        };
+
+        assert!(
+            air_collide_with_stage(
+                &previous_translation,
+                &translation,
+                &previous_ecb,
+                &ecb,
+                &stage_collision,
+                &[],
+                AirCollisionOptions {
+                    can_pass_through_soft_platforms: true,
+                    ..Default::default()
+                },
+            )
+            .is_none()
+        );
+
+        assert_eq!(
+            air_collide_with_stage(
+                &previous_translation,
+                &translation,
+                &previous_ecb,
+                &ecb,
+                &stage_collision,
+                &[],
+                Default::default(),
+            )
+            .expect("air dodges still collide with soft platforms")
+            .hit_position,
+            FGVec2::lit("0", "0")
+        );
+    }
+
+    #[test]
+    fn airborne_collision_still_hits_solid_floors_while_passing_down() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![solid_floor()],
+            ..StageCollision::default()
+        };
+        let previous_translation = FighterPreviousTranslation(FGVec2::lit("0", "2"));
+        let translation = FighterTranslation(FGVec2::lit("0", "-1"));
+        let previous_ecb = FighterPreviousECB {
+            bottom: FGVec2::ZERO,
+            top: FGVec2::ZERO,
+            left: FGVec2::ZERO,
+            right: FGVec2::ZERO,
+        };
+        let ecb = FighterECB {
+            bottom: FGVec2::ZERO,
+            top: FGVec2::ZERO,
+            left: FGVec2::ZERO,
+            right: FGVec2::ZERO,
+        };
+
+        let collision = air_collide_with_stage(
+            &previous_translation,
+            &translation,
+            &previous_ecb,
+            &ecb,
+            &stage_collision,
+            &[],
+            AirCollisionOptions {
+                can_pass_through_soft_platforms: true,
+                ..Default::default()
+            },
+        )
+        .expect("solid floors remain collidable while passing down");
+
+        assert_eq!(collision.line_id.polygon, 0);
+        assert_eq!(collision.hit_position, FGVec2::lit("0", "0"));
+    }
+
+    #[test]
+    fn upward_bottom_crossing_can_land_on_soft_platform() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![horizontal_platform("0")],
+            ..Default::default()
+        };
+        let previous_translation = FighterPreviousTranslation(FGVec2::lit("0", "-1"));
+        let mut translation = FighterTranslation(FGVec2::lit("0", "1"));
+        let mut velocity = FighterVelocity(FGVec2::lit("0", "2"));
+        let mut ecb = FighterECB::default();
+        let desired = FighterDesiredECB::from(ecb);
+
+        let collision = air_collide_with_stage_substepped(
+            &previous_translation,
+            &mut translation,
+            &mut velocity,
+            &mut ecb,
+            &desired,
+            &stage_collision,
+            &[],
+            AirCollisionOptions {
+                land_on_soft_platforms_from_below: true,
+                ..Default::default()
+            },
+        )
+        .expect("the upward bottom-point crossing should land on the platform");
+
+        assert_eq!(collision.hit_position, FGVec2::ZERO);
+        assert_eq!(collision.line_id, StageLineID { polygon: 0, segment: 0 });
+        assert_eq!(translation.0, FGVec2::ZERO);
+        assert_eq!(velocity.y, FGi32::ZERO);
+    }
+
+    #[test]
+    fn upward_platform_landing_requires_crossing_and_opt_in() {
+        let stage_collision = StageCollision {
+            stage_polys: vec![horizontal_platform("0")],
+            ..Default::default()
+        };
+        let previous_ecb = FighterPreviousECB::default();
+        let ecb = FighterECB::default();
+        let options = AirCollisionOptions {
+            land_on_soft_platforms_from_below: true,
+            ..Default::default()
+        };
+
+        assert!(
+            air_collide_with_stage(
+                &FighterPreviousTranslation(FGVec2::lit("0", "-2")),
+                &FighterTranslation(FGVec2::lit("0", "-1")),
+                &previous_ecb,
+                &ecb,
+                &stage_collision,
+                &[],
+                options,
+            )
+            .is_none()
+        );
+        assert!(
+            air_collide_with_stage(
+                &FighterPreviousTranslation(FGVec2::lit("0", "-1")),
+                &FighterTranslation(FGVec2::lit("0", "1")),
+                &previous_ecb,
+                &ecb,
+                &stage_collision,
+                &[],
+                Default::default(),
+            )
+            .is_none()
+        );
+    }
+
+    #[test]
+    fn upward_crossing_does_not_land_on_solid_or_ignored_platforms() {
+        let previous_translation = FighterPreviousTranslation(FGVec2::lit("0", "-1"));
+        let translation = FighterTranslation(FGVec2::lit("0", "1"));
+        let previous_ecb = FighterPreviousECB::default();
+        let ecb = FighterECB::default();
+        let options = AirCollisionOptions {
+            land_on_soft_platforms_from_below: true,
+            ..Default::default()
+        };
+        let solid_stage = StageCollision {
+            stage_polys: vec![solid_floor()],
+            ..Default::default()
+        };
+        let platform_stage = StageCollision {
+            stage_polys: vec![horizontal_platform("0")],
+            ..Default::default()
+        };
+
+        assert!(
+            air_collide_with_stage(
+                &previous_translation,
+                &translation,
+                &previous_ecb,
+                &ecb,
+                &solid_stage,
+                &[],
+                options,
+            )
+            .is_none()
+        );
+        assert!(
+            air_collide_with_stage(
+                &previous_translation,
+                &translation,
+                &previous_ecb,
+                &ecb,
+                &platform_stage,
+                &[0],
+                options,
+            )
+            .is_none()
+        );
+    }
+}

src/fighter/debug.rs

@@ -1,10 +1,9 @@
 //! Fighter debug views: gizmos and the egui inspector window.
 
-use std::sync::OnceLock;
 
-use bevy::color::palettes::css::ORANGE;
+use bevy::color::palettes::css::{ORANGE, ORANGE_RED, WHITE};
-use bevy::{color::palettes::css::YELLOW, prelude::*};
+use bevy::prelude::*;
-use bevy_egui::{EguiContexts, egui};
+use bevy_egui::{egui, EguiContexts};
 
 use crate::debug_tools::{DebugSettings, FighterDebugRowKind};
 use crate::fighter::animation::FighterAnimationFrame;
@@ -15,19 +14,21 @@ use crate::fighter::attack::{
 use crate::fighter::baked_animation::{BakedFighterAnimations, FighterBoneMatrices};
 use crate::fighter::ecb::FighterPreviousECB;
 use crate::fighter::errors::FighterErrors;
-use crate::fighter::hurtbox::FixedAffineCapsule;
 use crate::fighter::manifest::FighterManifest;
-use crate::fighter::state::{FighterState, air};
+use crate::fighter::state::{air, FighterState};
 use crate::fighter::visual::FighterAnimations;
 use crate::fighter::{
     Fighter, FighterECB, FighterFacingDirection, FighterHitboxes, FighterPreviousTranslation,
     FighterTranslation, FighterVelocity,
 };
+use crate::filled_gizmos::FilledGizmos;
 use crate::game_settings::GameSettings;
 use crate::input::FighterInput;
 use crate::math::int::FGi32;
 use crate::math::vec::FGVec2;
+use crate::math::vec3::FGVec3;
 use crate::player::Player;
+use crate::scripting::FighterAttackScript;
 
 pub fn debug_draw_ecb(
     ecbs: Query<(
@@ -37,17 +38,27 @@ pub fn debug_draw_ecb(
         &FighterPreviousTranslation,
     )>,
     mut gizmos: Gizmos,
+    mut filled_gizmos: FilledGizmos,
 ) {
     for (ecb, trf, ecb_prev, trf_prev) in ecbs {
+        gizmos.cross(
+            FGVec3::new(trf.0.x, trf.0.y, FGi32::ZERO).to_vec3(),
+            2.0,
+            bevy::color::palettes::css::BLUE,
+        );
+
+        let prev_transformed = ecb_prev.to_3d_lineloop(Transform::from_xyz(
+            trf_prev.x.to_num::<f32>(),
+            trf_prev.y.to_num(),
+            0.0,
+        ));
+        filled_gizmos.polygon(&prev_transformed, ORANGE_RED);
+
         let transformed =
             ecb.to_3d_lineloop(Transform::from_xyz(trf.x.to_num(), trf.y.to_num(), 0.0));
-        gizmos.lineloop(transformed, YELLOW);
+        filled_gizmos.polygon(&transformed, ORANGE);
-        let prev_transformed = ecb_prev.to_3d_lineloop(Transform::from_xyz(
+        gizmos.lineloop(transformed, WHITE);
-            trf_prev.x.to_num(),
+
-            trf_prev.y.to_num(),
-            -0.1,
-        ));
-        gizmos.lineloop(prev_transformed, ORANGE);
     }
 }
 pub fn fighter_debug(
@@ -138,6 +149,8 @@ pub fn fighter_debug(
                                     last_frame.movement.x, last_frame.movement.y
                                 ));
                             });
+
+                            ui.label(format!("Flick age Y {}", input.peek_movement_flick_dbg()));
                         }
                         FighterDebugRowKind::Position => {
                             ui.label(format!("Position: {:?}", translation.0));
@@ -153,31 +166,77 @@ pub fn fighter_debug(
     Ok(())
 }
 
-pub fn animation_debug(query: Query<(&GlobalTransform, &FighterBoneMatrices)>, mut gizmos: Gizmos) {
+pub fn animation_debug(
-    for (global_transform, matrices) in query {
+    query: Query<(
-        let (_, rotation, translation) = global_transform.to_scale_rotation_translation();
+        &FighterTranslation,
-        let marker_transform = Transform::from_translation(translation).with_rotation(rotation);
+        &FighterFacingDirection,
-        for (_, matrix) in matrices.iter() {
+        &FighterBoneMatrices,
+        &Fighter,
+    )>,
+    mut gizmos: Gizmos,
+    fighter_manifests: Res<Assets<FighterManifest>>,
+) {
+    for (global_transform, facing_dir, matrices, fighter) in query {
+        let Some(manifest) = fighter_manifests.get(&fighter.manifest) else {
+            continue;
+        };
+        let global_transform = global_transform.get_3d_transform(facing_dir);
+        let marker_transform = global_transform.to_mat4();
+        for (bone_name, matrix) in matrices.iter() {
             let pos = marker_transform.transform_point(Vec3::new(
                 matrix.cols[3][0].to_num(),
                 matrix.cols[3][1].to_num(),
                 matrix.cols[3][2].to_num(),
             ));
-            gizmos.cross(pos, 0.5, bevy::color::palettes::css::RED);
+
-            gizmos.axes(marker_transform, 1.0);
+            if manifest.ecb_bones.iter().any(|ecb_bone_name| ecb_bone_name == bone_name) {
+                gizmos.cross(pos, 1.0, bevy::color::palettes::css::GREEN);
+            } else {
+                gizmos.cross(pos, 0.5, bevy::color::palettes::css::RED);
+                gizmos.axes(marker_transform, 1.0);
+            }
+
         }
     }
 }
 
-pub fn hurtbox_debug(query: Query<&FighterSolvedHurtboxes>, mut gizmos: Gizmos) {
+pub fn hurtbox_debug(
+    query: Query<&FighterSolvedHurtboxes>,
+    mut filled_gizmos: FilledGizmos,
+) {
     for hurtboxes in &query {
         for hurtbox in &hurtboxes.0 {
-            draw_affine_capsule(&mut gizmos, hurtbox.capsule, YELLOW);
+            filled_gizmos.affine_capsule(
+                hurtbox.capsule.transform.to_mat4(),
+                hurtbox.capsule.radius.to_num(),
+                hurtbox.capsule.half_length.to_num(),
+                Color::srgba(1.0, 1.0, 0.0, 0.75),
+            );
         }
     }
 }
 
-fn draw_affine_capsule(
+pub fn ledge_grab_debug(query: Query<(&FighterTranslation, &Fighter)>, fighters: Res<Assets<FighterManifest>>, mut gizmos: Gizmos) {
+    for (translation, fighter) in query {
+        let Some(manifest) = fighters.get(&fighter.manifest) else {
+            continue;
+        };
+
+        let start_2d = translation.0 + manifest.ledge_grab_box_start;
+        let start_2d = Vec2::new(start_2d.x.to_num(), start_2d.y.to_num());
+
+        let end_2d = translation.0 + manifest.ledge_grab_box_end;
+        let end_2d = Vec2::new(end_2d.x.to_num(), end_2d.y.to_num());
+
+
+        let center = (start_2d + end_2d) * 0.5;
+        let size = (start_2d - end_2d).abs();
+        
+        gizmos.rect(Vec3::new(center.x, center.y, 0.0), size, bevy::color::palettes::css::BLUE);
+    }
+}
+
+/*fn draw_affine_capsule(
     gizmos: &mut Gizmos,
     capsule: FixedAffineCapsule,
     color: impl Into<Color> + Copy,
@@ -199,9 +258,9 @@ fn draw_affine_capsule(
     for &(start, end) in &wireframe.lines {
         gizmos.line(vertices[start], vertices[end], color);
     }
-}
+}*/
 
-struct CapsuleWireVertex {
+/*struct CapsuleWireVertex {
     direction: Vec3,
     center_sign: f32,
 }
@@ -209,9 +268,9 @@ struct CapsuleWireVertex {
 struct CapsuleWireframe {
     vertices: Vec<CapsuleWireVertex>,
     lines: Vec<(usize, usize)>,
-}
+}*/
 
-fn capsule_wireframe() -> &'static CapsuleWireframe {
+/*fn capsule_wireframe() -> &'static CapsuleWireframe {
     const RESOLUTION: usize = 16;
     const HEMISPHERE_STEPS: usize = 4;
     static WIREFRAME: OnceLock<CapsuleWireframe> = OnceLock::new();
@@ -292,7 +351,7 @@ fn capsule_wireframe() -> &'static CapsuleWireframe {
 
         CapsuleWireframe { vertices, lines }
     })
-}
+}*/
 
 #[cfg(test)]
 mod capsule_debug_tests {
@@ -312,7 +371,7 @@ mod capsule_debug_tests {
         assert!(marker.abs_diff_eq(Vec3::new(3.0, 4.0, 3.0), 1e-5));
     }
 
-    #[test]
+    /*#[test]
     fn capsule_wireframe_caps_extend_in_opposite_directions() {
         let wireframe = capsule_wireframe();
         let lower: Vec<_> = wireframe
@@ -330,7 +389,7 @@ mod capsule_debug_tests {
         assert!(upper.iter().all(|vertex| vertex.direction.y >= 0.0));
         assert!(lower.iter().any(|vertex| vertex.direction == Vec3::NEG_Y));
         assert!(upper.iter().any(|vertex| vertex.direction == Vec3::Y));
-    }
+    }*/
 }
 
 pub fn attack_debug(
@@ -342,6 +401,8 @@ pub fn attack_debug(
         &FighterAnimationFrame,
     )>,
     mut gizmos: Gizmos,
+    mut filled_gizmos: FilledGizmos,
+    attack_scripts: Res<Assets<FighterAttackScript>>
 ) {
     for (hitboxes, _matrices, _translation, _facing_direction, _frame) in query {
         if let Some(active_attack) = &hitboxes.0 {
@@ -352,21 +413,35 @@ pub fn attack_debug(
                     (solved_hitbox.capsule.start + solved_hitbox.capsule.end) * FGi32::lit("0.5");
                 let length = (start - end).length();
 
-                let attack_capsule = Capsule3d {
-                    half_length: length * 0.5,
-                    radius: solved_hitbox.capsule.radius.to_num(),
-                };
-
                 let aim_dir = (end - start).normalize_or(Vec3::Y);
 
                 let mut capsule_draw_trf = Transform::IDENTITY;
                 capsule_draw_trf.translation = center.to_vec3();
                 capsule_draw_trf.align(Dir3::Y, aim_dir, Dir3::X, aim_dir.any_orthonormal_vector());
 
+                let Some(script) = attack_scripts.get(&active_attack.script) else {
+                    continue;
+                };
+
+                let hitbox_color =  script.hitboxes.get(solved_hitbox.hitbox_idx).expect("This hitbox should be valid").get_debug_draw_color();
+                /*
+                let attack_capsule = Capsule3d {
+                    half_length: length * 0.5,
+                    radius: solved_hitbox.capsule.radius.to_num(),
+                };
                 gizmos.primitive_3d(
                     &attack_capsule,
                     capsule_draw_trf.to_isometry(),
-                    bevy::color::palettes::css::RED,
+                    hitbox_color,
+                );*/
+
+                let hitbox_inner_color = bevy::color::Srgba { alpha: 0.18, ..hitbox_color };
+
+                filled_gizmos.capsule(
+                    capsule_draw_trf.to_isometry(),
+                    solved_hitbox.capsule.radius.to_num(),
+                    length * 0.5,
+                    hitbox_inner_color,
                 );
 
                 gizmos.cross(start, 1.0, bevy::color::palettes::css::GREEN);

src/fighter/ecb.rs

@@ -1,28 +1,114 @@
 use bevy::prelude::*;
 
-use crate::math::{int::FGi32, vec::FGVec2};
+use crate::{
+    fighter::{
+        FighterFacingDirection, FighterSurfaceState, FighterTranslation,
+        baked_animation::FighterBoneMatrices,
+    },
+    math::{int::FGi32, vec::FGVec2},
+};
 
-/// Environment collision box: the diamond used to resolve a fighter against
+#[derive(Component, Debug, Clone, Copy, Hash, Default)]
-/// the stage. Purely geometry — the collision response lives in
+#[require(FighterPreviousECB, FighterDesiredECB)]
-/// [`super::collision`].
-#[derive(Component, Debug, Clone, Copy, Hash)]
-#[require(FighterPreviousECB)]
 pub struct FighterECB {
-    pub vertical_half: FGi32,
+    pub top: FGVec2,
-    pub horizontal_half: FGi32,
+    pub bottom: FGVec2,
+    pub left: FGVec2,
+    pub right: FGVec2,
+}
+
+#[derive(Component, Debug, Clone, Copy, Hash, Default)]
+pub struct FighterDesiredECB {
+    pub top: FGVec2,
+    pub bottom: FGVec2,
+    pub left: FGVec2,
+    pub right: FGVec2,
+}
+
+#[derive(Component, Debug, Clone)]
+pub struct FighterECBBoneIndices {
+    pub indices: Vec<usize>,
 }
 
 #[derive(Component, Debug, Clone, Copy, Default, Hash)]
 pub struct FighterPreviousECB {
-    pub vertical_half: FGi32,
+    pub top: FGVec2,
-    pub horizontal_half: FGi32,
+    pub bottom: FGVec2,
+    pub left: FGVec2,
+    pub right: FGVec2,
 }
 
 impl From<FighterECB> for FighterPreviousECB {
     fn from(ecb: FighterECB) -> Self {
         Self {
-            vertical_half: ecb.vertical_half,
+            top: ecb.top,
-            horizontal_half: ecb.horizontal_half,
+            bottom: ecb.bottom,
+            left: ecb.left,
+            right: ecb.right,
+        }
+    }
+}
+
+impl From<FighterECB> for FighterDesiredECB {
+    fn from(ecb: FighterECB) -> Self {
+        Self {
+            top: ecb.top,
+            bottom: ecb.bottom,
+            left: ecb.left,
+            right: ecb.right,
+        }
+    }
+}
+
+impl FighterDesiredECB {
+    pub fn as_ecb(self) -> FighterECB {
+        FighterECB {
+            top: self.top,
+            bottom: self.bottom,
+            left: self.left,
+            right: self.right,
+        }
+    }
+
+    pub fn validate(&mut self) {
+        let minimum = FGi32::lit("1.0");
+        if (self.top.y - self.bottom.y).abs() < minimum {
+            self.top.y += minimum;
+            let midpoint = (self.top.y + self.bottom.y) / FGi32::lit("2.0");
+            self.left.y = midpoint;
+            self.right.y = midpoint;
+        }
+        if self.top.y < minimum {
+            self.top.y = minimum;
+        }
+        if self.left.x > -minimum {
+            self.left.x = -minimum;
+        }
+        if self.right.x < minimum {
+            self.right.x = minimum;
+        }
+        if self.top.y < self.bottom.y {
+            self.top.y = self.bottom.y + minimum;
+        }
+
+        let midpoint = (self.top.y + self.bottom.y) / FGi32::lit("2.0");
+        if self.left.y < self.bottom.y || self.left.y > self.top.y {
+            self.left.y = midpoint;
+        }
+        if self.right.y < self.bottom.y || self.right.y > self.top.y {
+            self.left.y = midpoint;
+            self.right.y = midpoint;
+        }
+        let epsilon = FGi32::from_bits(66);
+        if self.top.y - self.right.y < epsilon
+            || self.right.y - self.bottom.y < epsilon
+        {
+            self.right.y = midpoint;
+        }
+        if self.top.y - self.left.y < epsilon
+            || self.left.y - self.bottom.y < epsilon
+        {
+            self.left.y = midpoint;
         }
     }
 }
@@ -33,55 +119,144 @@ pub fn snapshot_fighter_ecb(fighters: Query<(&FighterECB, &mut FighterPreviousEC
     }
 }
 
+pub fn interpolate_ecb(ecb: &mut FighterECB, desired: FighterDesiredECB, time: FGi32) {
+    let lerp = |a: FGVec2, b: FGVec2| a + (b - a) * time;
+    ecb.top = lerp(ecb.top, desired.top);
+    ecb.bottom = lerp(ecb.bottom, desired.bottom);
+    ecb.left = lerp(ecb.left, desired.left);
+    ecb.right = lerp(ecb.right, desired.right);
+}
+
+pub fn ecb_max_delta(ecb: &FighterECB, desired: &FighterDesiredECB) -> FGi32 {
+    [
+        (desired.left.x - ecb.left.x).abs(),
+        (desired.right.x - ecb.right.x).abs(),
+        (desired.top.y - ecb.top.y).abs(),
+        (desired.right.y - ecb.right.y).abs(),
+    ]
+    .into_iter()
+    .max()
+    .unwrap_or(FGi32::ZERO)
+}
+
 impl FighterECB {
     pub fn to_3d_lineloop(&self, trf: Transform) -> [Vec3; 4] {
-        let rel_up = trf.transform_point(Vec3::new(
+        [self.top, self.right, self.bottom, self.left]
-            0.0,
+            .map(|point| trf.transform_point(Vec3::new(point.x.to_num(), point.y.to_num(), 0.0)))
-            (self.vertical_half + self.vertical_half).to_num(),
-            0.0,
-        ));
-        let rel_down = trf.transform_point(Vec3::new(0.0, 0.0, 0.0));
-        let rel_left = trf.transform_point(Vec3::new(
-            (-self.horizontal_half).to_num(),
-            self.vertical_half.to_num(),
-            0.0,
-        ));
-        let rel_right = trf.transform_point(Vec3::new(
-            self.horizontal_half.to_num(),
-            self.vertical_half.to_num(),
-            0.0,
-        ));
-        [rel_up, rel_right, rel_down, rel_left]
     }
 
     pub fn get_bottom_point(&self) -> FGVec2 {
-        FGVec2::new(FGi32::ZERO, FGi32::ZERO)
+        self.bottom
+    }
+
+    /// Change the local origin to the bottom point without moving the ECB in
+    /// world space. Grounded fighters use the floor contact as their origin.
+    pub fn rebase_onto_bottom(&mut self) -> FGVec2 {
+        let bottom = self.bottom;
+        self.top -= bottom;
+        self.left -= bottom;
+        self.right -= bottom;
+        self.bottom = FGVec2::ZERO;
+        bottom
     }
 }
 
 impl FighterPreviousECB {
     pub fn to_3d_lineloop(&self, trf: Transform) -> [Vec3; 4] {
-        let rel_up = trf.transform_point(Vec3::new(
+        [self.top, self.right, self.bottom, self.left]
-            0.0,
+            .map(|point| trf.transform_point(Vec3::new(point.x.to_num(), point.y.to_num(), 0.0)))
-            (self.vertical_half + self.vertical_half).to_num(),
-            0.0,
-        ));
-        let rel_down = trf.transform_point(Vec3::new(0.0, 0.0, 0.0));
-        let rel_left = trf.transform_point(Vec3::new(
-            (-self.horizontal_half).to_num(),
-            self.vertical_half.to_num(),
-            0.0,
-        ));
-        let rel_right = trf.transform_point(Vec3::new(
-            self.horizontal_half.to_num(),
-            self.vertical_half.to_num(),
-            0.0,
-        ));
-        [rel_up, rel_right, rel_down, rel_left]
     }
 
     pub fn get_bottom_point(&self) -> FGVec2 {
-        FGVec2::new(FGi32::ZERO, FGi32::ZERO)
+        self.bottom
+    }
+}
+
+pub fn update_ecb(
+    query: Query<(
+        &mut FighterDesiredECB,
+        &FighterSurfaceState,
+        &FighterECBBoneIndices,
+        &FighterBoneMatrices,
+        &FighterTranslation,
+        &FighterFacingDirection,
+    )>,
+) {
+    for (mut desired, surface_state, bone_indices, bone_matrices, translation, facing_dir) in query
+    {
+        let trf = translation.get_3d_transform(facing_dir);
+
+        let transformed_ecb_bones = bone_indices
+            .indices
+            .iter()
+            .filter_map(|idx| {
+                let Some((_, bone_matrix)) = bone_matrices.get_by_idx(*idx) else {
+                    return None;
+                };
+
+                let pt = trf.transform_point(bone_matrix.get_translation());
+
+                Some(FGVec2::new(pt.x, pt.y) - translation.0)
+            })
+            .collect::<Vec<_>>();
+
+        let max_x = transformed_ecb_bones
+            .iter()
+            .max_by(|a, b| a.x.cmp(&b.x))
+            .map(|final_val| final_val.x)
+            .unwrap_or(FGi32::lit("0.5"));
+        let min_x = transformed_ecb_bones
+            .iter()
+            .min_by(|a, b| a.x.cmp(&b.x))
+            .map(|final_val| final_val.x)
+            .unwrap_or(FGi32::lit("-0.5"));
+        let max_y = transformed_ecb_bones
+            .iter()
+            .max_by(|a, b| a.y.cmp(&b.y))
+            .map(|final_val| final_val.y)
+            .unwrap_or(FGi32::lit("0.5"));
+        let min_y = transformed_ecb_bones
+            .iter()
+            .min_by(|a, b| a.y.cmp(&b.y))
+            .map(|final_val| final_val.y)
+            .unwrap_or(FGi32::lit("-0.5"));
+
+        let midpoint_height = (max_y + min_y) / FGi32::lit("2.0");
+        let top = FGVec2::new(FGi32::ZERO, max_y);
+        let bottom = FGVec2::new(FGi32::ZERO, min_y);
+        let left = FGVec2::new(min_x, midpoint_height);
+        let right = FGVec2::new(max_x, midpoint_height);
+
+        let ecb_lock_frames_remaining = if let FighterSurfaceState::Airborne {
+            ecb_lock_frames_remaining,
+            ..
+        } = surface_state
+        {
+            *ecb_lock_frames_remaining
+        } else {
+            0
+        };
+
+        desired.top = top;
+
+        if ecb_lock_frames_remaining == 0 {
+            desired.bottom = bottom;
+        }
+
+        desired.left = left;
+        desired.right = right;
+
+        if surface_state.is_grounded() {
+            desired.bottom = FGVec2::ZERO;
+        }
+        desired.validate();
+    }
+}
+
+pub fn decrement_ecb_lockout(surface_states: Query<&mut FighterSurfaceState>) {
+    for mut state in surface_states {
+        state.tick_ecb_lock();
+        state.tick_ignored_polygons();
     }
 }
 
@@ -92,12 +267,72 @@ mod tests {
     #[test]
     fn previous_ecb_copies_current_dimensions() {
         let current = FighterECB {
-            vertical_half: FGi32::lit("0.5"),
+            bottom: FGVec2::lit("0.0", "-0.5"),
-            horizontal_half: FGi32::lit("0.25"),
+            top: FGVec2::lit("0.0", "0.5"),
+            left: FGVec2::lit("-0.5", "0.0"),
+            right: FGVec2::lit("0.5", "0.0"),
         };
         let previous = FighterPreviousECB::from(current);
 
-        assert_eq!(previous.vertical_half, current.vertical_half);
+        assert_eq!(previous.top, current.top);
-        assert_eq!(previous.horizontal_half, current.horizontal_half);
+        assert_eq!(previous.bottom, current.bottom);
+        assert_eq!(previous.left, current.left);
+        assert_eq!(previous.right, current.right);
+    }
+
+    #[test]
+    fn interpolation_reaches_target_with_full_step() {
+        let mut current = FighterECB {
+            top: FGVec2::lit("0", "1"),
+            bottom: FGVec2::lit("0", "0"),
+            left: FGVec2::lit("-1", "0.5"),
+            right: FGVec2::lit("1", "0.5"),
+        };
+        let desired = FighterDesiredECB {
+            top: FGVec2::lit("0", "3"),
+            bottom: FGVec2::lit("0", "-1"),
+            left: FGVec2::lit("-2", "1"),
+            right: FGVec2::lit("2", "1"),
+        };
+        interpolate_ecb(&mut current, desired, FGi32::ONE);
+        assert_eq!(current.top, desired.top);
+        assert_eq!(current.bottom, desired.bottom);
+        assert_eq!(current.left, desired.left);
+        assert_eq!(current.right, desired.right);
+    }
+
+    #[test]
+    fn validation_repairs_tiny_and_out_of_range_diamond() {
+        let mut desired = FighterDesiredECB {
+            top: FGVec2::lit("0", "0.25"),
+            bottom: FGVec2::lit("0", "0"),
+            left: FGVec2::lit("0", "4"),
+            right: FGVec2::lit("0", "-4"),
+        };
+        desired.validate();
+
+        assert_eq!(desired.top.y, FGi32::lit("1.25"));
+        assert_eq!(desired.left.x, FGi32::lit("-1"));
+        assert_eq!(desired.right.x, FGi32::lit("1"));
+        assert_eq!(desired.left.y, FGi32::lit("0.625"));
+        assert_eq!(desired.right.y, FGi32::lit("0.625"));
+    }
+
+    #[test]
+    fn rebasing_onto_bottom_preserves_world_points() {
+        let origin = FGVec2::lit("4", "8");
+        let mut ecb = FighterECB {
+            top: FGVec2::lit("0", "3"),
+            bottom: FGVec2::lit("0", "-1"),
+            left: FGVec2::lit("-2", "1"),
+            right: FGVec2::lit("2", "1"),
+        };
+        let old_world_points = [ecb.top, ecb.bottom, ecb.left, ecb.right].map(|p| origin + p);
+        let new_origin = origin + ecb.bottom;
+        ecb.rebase_onto_bottom();
+        let new_world_points = [ecb.top, ecb.bottom, ecb.left, ecb.right].map(|p| new_origin + p);
+
+        assert_eq!(old_world_points, new_world_points);
+        assert_eq!(ecb.bottom, FGVec2::ZERO);
     }
 }

src/fighter/manifest.rs

@@ -8,11 +8,7 @@ use strum::IntoEnumIterator;
 use strum_macros::EnumIter;
 
 use crate::{
-    AppState,
+    AppState, fighter::{FighterAttributes, FighterCameraProfile, animation::AnimKind, attack::AttackKind}, game_settings::GameSettings, math::{int::FGi32, vec::FGVec2, vec3::FGVec3}, texture_reference::TextureReference,
-    fighter::{FighterAttributes, FighterCameraProfile, animation::AnimKind, attack::AttackKind},
-    game_settings::GameSettings,
-    math::{int::FGi32, vec3::FGVec3},
-    texture_reference::TextureReference,
 };
 
 #[derive(
@@ -62,9 +58,19 @@ pub struct FighterManifest {
     pub icon: TextureReference,
     pub attributes: FighterAttributes,
     pub camera: FighterCameraProfile,
+    /// Bone whose model-space translation drives gameplay root motion.
+    #[serde(default = "default_root_motion_bone")]
+    pub root_motion_bone: String,
     pub animations: HashMap<AnimKind, String>,
     pub attack_scripts: HashMap<AttackKind, String>,
     pub hurtboxes: Vec<FighterHurtbox>,
+    pub ecb_bones: Vec<String>,
+    pub ledge_grab_box_start: FGVec2,
+    pub ledge_grab_box_end: FGVec2,
+}
+
+fn default_root_motion_bone() -> String {
+    "root".into()
 }
 
 #[derive(Resource)]

src/fighter/mod.rs

@@ -10,6 +10,7 @@ pub mod animation;
 pub mod attack;
 pub mod attributes;
 pub mod baked_animation;
+pub mod blast_zones;
 pub mod collision;
 pub mod debug;
 pub mod ecb;
@@ -17,7 +18,9 @@ pub mod errors;
 pub mod hurtbox;
 pub mod manifest;
 pub mod motion;
+pub mod push;
 pub mod state;
+pub mod surface;
 pub mod visual;
 
 // The fighter components are re-exported so the rest of the crate can say
@@ -28,18 +31,31 @@ pub use attributes::FighterAttributes;
 pub use ecb::FighterECB;
 pub use manifest::FighterId;
 pub use motion::{
-    FighterPreviousFacingDirection, FighterPreviousTranslation, FighterTranslation,
+    FighterPresentationSnap, FighterPreviousFacingDirection, FighterPreviousTranslation,
-    FighterVelocity, Grounded,
+    FighterTranslation, FighterVelocity,
 };
+pub use surface::FighterSurfaceState;
 
 use crate::{
-    AppState, fighter::{
+    AppState,
+    fighter::{
         attack::{
             AttackKind, FighterAttackPlugin, FighterAttackScriptAssets, FighterDamage,
-            FighterKnockbackVelocity, FighterPendingHitReaction, FighterSolvedHurtboxes,
+            FighterKnockbackState, FighterKnockbackVelocity, FighterPendingHitReaction,
-            FighterStaleMoveQueue,
+            FighterSolvedHurtboxes, FighterStaleMoveQueue,
-        }, baked_animation::{FighterBoneIndexMap, FighterBoneMatrices}, manifest::FighterManifest, state::{FighterState, air::AirborneStateCommon, fall::FallState}, visual::FighterAnimations,
+        },
-    }, input::FighterInput, math::{int::FGi32, vec::FGVec2}, player::Player, schedule::GameplaySet, scripting::FighterAttackScript, stage::line::StageCollision,
+        baked_animation::FighterBoneIndexMap,
+        ecb::{FighterDesiredECB, FighterECBBoneIndices},
+        manifest::FighterManifest,
+        state::{FighterState, air::AirborneStateCommon, fall::FallState},
+        visual::{FighterAnimations, FighterInvulnerabilityVisualState},
+    },
+    game_settings::GameSettings,
+    input::FighterInput,
+    math::{int::FGi32, vec::FGVec2},
+    player::Player,
+    schedule::GameplaySet,
+    scripting::FighterAttackScript,
 };
 use state::state_interrupt_system;
 
@@ -58,14 +74,14 @@ pub enum FighterFacingDirection {
 pub enum FighterHitstopShakeKind {
     #[default]
     Horizontal,
-    Vertical
+    Vertical,
 }
 
 #[derive(Component, Copy, Clone, Hash, Debug, PartialEq, Reflect, Default)]
 pub enum FighterHitstopShakeRole {
     #[default]
     Attacker,
-    Receiver
+    Receiver,
 }
 
 #[derive(Component, Default, Copy, Clone, Hash)]
@@ -73,7 +89,7 @@ pub struct FighterHitstopShake {
     pub remaining_frames: u32,
     pub total_frames: u32,
     pub kind: FighterHitstopShakeKind,
-    pub role: FighterHitstopShakeRole
+    pub role: FighterHitstopShakeRole,
 }
 
 #[derive(Component, Default, Copy, Clone, Hash)]
@@ -82,6 +98,64 @@ pub struct FighterHitstop {
     pub remaining_frames: u32,
 }
 
+#[derive(Component, Default, Copy, Clone, Hash, Debug, PartialEq, Eq)]
+pub struct FighterLedgeInformation {
+    pub regrab_lockout_remaining_frames: u32,
+    pub grab_count: u32,
+}
+
+impl FighterLedgeInformation {
+    pub fn start(&mut self, duration_frames: u32) {
+        self.regrab_lockout_remaining_frames = duration_frames;
+    }
+
+    pub fn is_regrab_lockout_active(&self) -> bool {
+        self.regrab_lockout_remaining_frames > 0
+    }
+
+    fn tick(&mut self) {
+        self.regrab_lockout_remaining_frames =
+            self.regrab_lockout_remaining_frames.saturating_sub(1);
+    }
+}
+
+#[cfg(test)]
+mod ledge_grab_lockout_tests {
+    use super::FighterLedgeInformation;
+
+    #[test]
+    fn lockout_expires_after_the_requested_number_of_ticks() {
+        let mut lockout = FighterLedgeInformation::default();
+        lockout.start(2);
+
+        assert!(lockout.is_regrab_lockout_active());
+        lockout.tick();
+        assert!(lockout.is_regrab_lockout_active());
+        lockout.tick();
+        assert!(!lockout.is_regrab_lockout_active());
+    }
+
+    #[test]
+    fn zero_duration_does_not_enable_lockout() {
+        let mut lockout = FighterLedgeInformation::default();
+        lockout.start(0);
+
+        assert!(!lockout.is_regrab_lockout_active());
+    }
+}
+
+#[derive(Component, Default, Copy, Clone, Hash)]
+pub enum FighterInvulnerabilityState {
+    #[default]
+    Vulnerable,
+    Invulnerable {
+        frames_remaining: Option<u32>,
+    },
+    Intangible {
+        frames_remaining: Option<u32>,
+    },
+}
+
 impl FighterFacingDirection {
     fn reverse(&self) -> Self {
         match self {
@@ -126,14 +200,22 @@ impl FighterFacingDirection {
 #[require(Transform)]
 pub struct FighterVisual;
 
+#[derive(Component, DerefMut, Deref, Debug, Default, Hash, Clone, Copy)]
+pub struct FighterPendingRespawn(bool);
+
 #[derive(Component)]
 #[require(
     FighterStaleMoveQueue,
     FighterDamage,
     FighterPendingHitReaction,
+    FighterPendingRespawn,
     FighterHitstop,
+    FighterLedgeInformation,
     FighterKnockbackVelocity,
+    FighterKnockbackState,
     FighterTranslation,
+    FighterInvulnerabilityState,
+    FighterInvulnerabilityVisualState
 )]
 pub struct Fighter {
     pub manifest: Handle<FighterManifest>,
@@ -146,6 +228,10 @@ impl Plugin for FighterPlugin {
     fn build(&self, app: &mut App) {
         app.add_plugins(FighterAttackPlugin)
             // Every state gets a chance to interrupt itself, in priority order.
+            .add_systems(
+                GgrsSchedule,
+                motion::clear_fighter_presentation_snaps.in_set(GameplaySet::Input),
+            )
             .add_systems(
                 GgrsSchedule,
                 (
@@ -158,7 +244,10 @@ impl Plugin for FighterPlugin {
             )
             .add_systems(
                 GgrsSchedule,
-                (state::state_update_system, decay_hitstop)
+                (
+                    state::state_update_system,
+                    decay_invulnerability,
+                )
                     .chain()
                     .in_set(GameplaySet::StateUpdate),
             )
@@ -170,15 +259,36 @@ impl Plugin for FighterPlugin {
             )*/
             .add_systems(
                 GgrsSchedule,
-                state::state_collision_interrupt_system.in_set(GameplaySet::Collision),
+                (
+                    (
+                        blast_zones::apply_blast_zones,
+                        ecb::decrement_ecb_lockout,
+                        ecb::update_ecb,
+                        state::state_collision_interrupt_system,
+                        // Every gameplay phase must observe the same hitstop value.
+                        decay_hitstop,
+                        decay_ledge_grab_lockout,
+                    )
+                        .chain(),
+                    baked_animation::resample_fighter_bone_matrices,
+                )
+                    .chain()
+                    .in_set(GameplaySet::Collision),
             )
             .add_systems(
-                Update,
+                GgrsSchedule,
+                push::apply_grounded_pushes
+                    .before(state::state_update_system)
+                    .in_set(GameplaySet::StateUpdate),
+            )
+            .add_systems(
+                PostUpdate,
                 (
                     motion::apply_fighter_translation_to_visuals,
                     animation::apply_animation,
                 )
                     .chain()
+                    .before(bevy::transform::TransformSystems::Propagate)
                     .run_if(in_state(crate::AppState::InMatch)),
             )
             // Rollback registration lives next to the systems that write these
@@ -186,6 +296,8 @@ impl Plugin for FighterPlugin {
             // is a desync waiting to happen.
             .rollback_component_with_copy::<FighterECB>()
             .checksum_component_with_hash::<FighterECB>()
+            .rollback_component_with_copy::<FighterDesiredECB>()
+            .checksum_component_with_hash::<FighterDesiredECB>()
             .rollback_component_with_clone::<FighterStaleMoveQueue>()
             .checksum_component_with_hash::<FighterStaleMoveQueue>()
             .rollback_component_with_copy::<ecb::FighterPreviousECB>()
@@ -196,27 +308,42 @@ impl Plugin for FighterPlugin {
             .checksum_component_with_hash::<FighterTranslation>()
             .rollback_component_with_copy::<FighterPreviousTranslation>()
             .checksum_component_with_hash::<FighterPreviousTranslation>()
+            .rollback_component_with_copy::<FighterPresentationSnap>()
+            .checksum_component_with_hash::<FighterPresentationSnap>()
             .rollback_component_with_copy::<FighterPreviousFacingDirection>()
             .checksum_component_with_hash::<FighterPreviousFacingDirection>()
             .rollback_component_with_copy::<animation::FighterAnimationFrame>()
             .checksum_component_with_hash::<animation::FighterAnimationFrame>()
-            .rollback_component_with_copy::<Grounded>()
+            .rollback_component_with_clone::<FighterSurfaceState>()
-            .checksum_component_with_hash::<Grounded>()
+            .checksum_component_with_hash::<FighterSurfaceState>()
             .rollback_component_with_copy::<FighterFacingDirection>()
             .rollback_component_with_copy::<FighterDamage>()
             .checksum_component_with_hash::<FighterDamage>()
             .rollback_component_with_clone::<FighterPendingHitReaction>()
             .checksum_component_with_hash::<FighterPendingHitReaction>()
+            .rollback_component_with_copy::<FighterPendingRespawn>()
+            .checksum_component_with_hash::<FighterPendingRespawn>()
             .rollback_component_with_copy::<FighterHitstop>()
             .checksum_component_with_hash::<FighterHitstop>()
+            .rollback_component_with_copy::<FighterLedgeInformation>()
+            .checksum_component_with_hash::<FighterLedgeInformation>()
+            .rollback_component_with_copy::<FighterInvulnerabilityState>()
+            .checksum_component_with_hash::<FighterInvulnerabilityState>()
             .rollback_component_with_copy::<FighterKnockbackVelocity>()
             .checksum_component_with_hash::<FighterKnockbackVelocity>()
-            .rollback_resource_with_reflect::<StageCollision>()
+            .rollback_component_with_copy::<FighterKnockbackState>()
+            .checksum_component_with_hash::<FighterKnockbackState>()
+            .rollback_component_with_clone::<baked_animation::FighterBoneMatrices>()
+            .checksum_component_with_hash::<baked_animation::FighterBoneMatrices>()
             // Debug views.
             .add_systems(
                 FixedPostUpdate,
                 debug::debug_draw_ecb.run_if(crate::debug_tools::ecb_enabled),
             )
+            .add_systems(
+                FixedPostUpdate,
+                debug::ledge_grab_debug.run_if(crate::debug_tools::ledge_grab_enabled),
+            )
             .add_systems(
                 EguiPrimaryContextPass,
                 debug::fighter_debug.run_if(crate::debug_tools::fighter_info_enabled),
@@ -236,17 +363,18 @@ impl Plugin for FighterPlugin {
                     .run_if(crate::debug_tools::attack_hitboxes_enabled)
                     .run_if(in_state(AppState::InMatch)),
             )
+            .add_systems(
+                FixedPostUpdate,
+                visual::update_status_colors.run_if(resource_exists::<GameSettings>),
+            )
             .add_systems(
                 FixedPostUpdate,
                 debug::hurtbox_debug.run_if(crate::debug_tools::hurtboxes_enabled),
             )
             .rollback_component_with_clone::<FighterState>()
             .rollback_component_with_clone::<FighterHitboxes>()
-            .rollback_component_with_clone::<FighterBoneMatrices>()
             .rollback_component_with_clone::<FighterHitstopShake>()
             .checksum_component_with_hash::<FighterHitboxes>()
-            .rollback_component_with_clone::<FighterSolvedHurtboxes>()
-            .checksum_component_with_hash::<FighterSolvedHurtboxes>()
             .checksum_component_with_hash::<FighterState>()
             .checksum_component_with_hash::<FighterFacingDirection>()
             .register_type::<FighterFacingDirection>();
@@ -258,8 +386,14 @@ pub struct FighterActiveAttack {
     pub script: Handle<FighterAttackScript>,
     pub active_hitboxes: Vec<usize>,
     pub solved_hitboxes: Vec<attack::FighterSolvedHitbox>,
+    pub hit_groups: Vec<FighterHitGroupState>,
+    pub stalled: bool,
+}
+
+#[derive(Clone, Debug, Hash)]
+pub struct FighterHitGroupState {
+    pub group: u32,
     pub hit_fighters: Vec<Entity>,
-    pub stalled: bool
 }
 
 #[derive(Component, Clone, Debug, Default, Hash)]
@@ -268,34 +402,40 @@ pub struct FighterHitboxes(pub Option<FighterActiveAttack>);
 pub fn spawn_fighter(
     commands: &mut Commands,
     player_handle: usize,
+    controller_port: usize,
     spawn_position: FGVec2,
     manifest: Handle<FighterManifest>,
     model_scale: FGi32,
     animations: FighterAnimations,
     attack_scripts: FighterAttackScriptAssets,
     visual_root: WorldAssetRoot,
+    ecb_bone_indices: Vec<usize>,
 ) -> Entity {
     commands
         .spawn((
             Name(format!("Fighter {player_handle}").into()),
             Player {
                 handle: player_handle,
+                controller_port,
             },
             Fighter { manifest: manifest },
             FighterFacingDirection::Right,
             FighterPreviousFacingDirection(FighterFacingDirection::Right),
+            FighterSurfaceState::default(),
             Transform::from_scale(Vec3::splat(model_scale.to_num())),
             (
-                FighterECB {
+                FighterECB::default(),
-                    vertical_half: FGi32::lit("5.0"),
+                FighterDesiredECB::default(),
-                    horizontal_half: FGi32::lit("2.5"),
-                },
                 FighterHitboxes::default(),
+                FighterECBBoneIndices {
+                    indices: ecb_bone_indices,
+                },
             ),
             (
                 FighterVelocity::default(),
                 FighterTranslation(spawn_position),
                 FighterPreviousTranslation(spawn_position),
+                FighterPresentationSnap::default(),
             ),
             visual_root,
             animations,
@@ -320,3 +460,40 @@ pub fn decay_hitstop(query: Query<(&mut FighterHitstop, &mut FighterHitstopShake
         hitstop_shake.remaining_frames = hitstop_shake.remaining_frames.saturating_sub(1);
     }
 }
+
+pub fn decay_ledge_grab_lockout(query: Query<&mut FighterLedgeInformation>) {
+    for mut lockout in query {
+        lockout.tick();
+    }
+}
+
+pub fn decay_invulnerability(query: Query<&mut FighterInvulnerabilityState>) {
+    for invuln_state in query {
+        let invuln_state = invuln_state.into_inner();
+        let frames_remaining = match invuln_state {
+            FighterInvulnerabilityState::Vulnerable => None,
+            FighterInvulnerabilityState::Invulnerable { frames_remaining } => {
+                if let Some(frames_remaining) = frames_remaining {
+                    *frames_remaining = frames_remaining.saturating_sub(1);
+                    Some(*frames_remaining)
+                } else {
+                    None
+                }
+            }
+            FighterInvulnerabilityState::Intangible { frames_remaining } => {
+                if let Some(frames_remaining) = frames_remaining {
+                    *frames_remaining = frames_remaining.saturating_sub(1);
+                    Some(*frames_remaining)
+                } else {
+                    None
+                }
+            }
+        };
+
+        if let Some(frames_remaining) = frames_remaining {
+            if frames_remaining == 0 {
+                *invuln_state = FighterInvulnerabilityState::Vulnerable;
+            }
+        }
+    }
+}

src/fighter/motion.rs

@@ -5,25 +5,27 @@ use bevy::prelude::*;
 use bevy_ggrs::GgrsFrameTiming;
 
 use crate::debug_tools::PresentationMotionMode;
-use crate::fighter::{FighterHitstopShake};
+use crate::fighter::FighterHitstopShake;
 use crate::game_settings::GameSettings;
 use crate::{
-    fighter::{FighterECB, FighterFacingDirection, baked_animation::FixedMat4},
+    fighter::{FighterFacingDirection, baked_animation::FixedMat4},
     math::{int::FGi32, vec::FGVec2, vec3::FGVec3},
 };
 
 #[derive(Component, Clone, Copy, Hash)]
 pub struct FighterPreviousFacingDirection(pub FighterFacingDirection);
 
-#[derive(Component, Clone, Copy, Hash)]
-pub struct Grounded;
-
 #[derive(Component, Deref, DerefMut, Default, Debug, Clone, Copy, Hash)]
 pub struct FighterVelocity(pub FGVec2);
 
 #[derive(Component, Deref, DerefMut, Default, Clone, Copy, Hash)]
 pub struct FighterPreviousTranslation(pub FGVec2);
 
+/// Marks a simulation frame whose position changed discontinuously for
+/// presentation purposes (for example, a landing correction).
+#[derive(Component, Default, Clone, Copy, Hash, Debug, PartialEq, Eq)]
+pub struct FighterPresentationSnap(pub bool);
+
 #[derive(Component, Deref, DerefMut, Default, Clone, Copy, Hash)]
 #[require(FighterPreviousTranslation)]
 pub struct FighterTranslation(pub FGVec2);
@@ -55,11 +57,31 @@ pub fn sample_presentation_translation(
     }
 }
 
+pub fn sample_presentation_translation_with_snap(
+    previous: FighterPreviousTranslation,
+    current: FighterTranslation,
+    overstep_fraction: f32,
+    mode: PresentationMotionMode,
+    snapped: FighterPresentationSnap,
+) -> Vec2 {
+    if snapped.0 {
+        Vec2::new(current.x.to_num(), current.y.to_num())
+    } else {
+        sample_presentation_translation(previous, current, overstep_fraction, mode)
+    }
+}
+
+pub fn clear_fighter_presentation_snaps(mut fighters: Query<&mut FighterPresentationSnap>) {
+    for mut snap in &mut fighters {
+        snap.0 = false;
+    }
+}
+
 pub fn apply_fighter_translation_to_visuals(
     query: Query<(
         &FighterTranslation,
         &FighterPreviousTranslation,
-        &FighterECB,
+        &FighterPresentationSnap,
         &FighterHitstopShake,
         &mut Transform,
     )>,
@@ -68,33 +90,43 @@ pub fn apply_fighter_translation_to_visuals(
     game_settings: Res<GameSettings>,
 ) {
     let overstep_fraction = timing.overstep_fraction();
-    for (translation, previous_translation, ecb, hitstop_shake, mut transform) in query {
+    for (translation, previous_translation, presentation_snap, hitstop_shake, mut transform) in query {
-        let translation = sample_presentation_translation(
+        let translation = sample_presentation_translation_with_snap(
             *previous_translation,
             *translation,
             overstep_fraction,
             debug_settings.motion_sampling,
+            *presentation_snap,
         );
-        let bottom = ecb.get_bottom_point();
         transform.translation = Vec3::new(
-            translation.x + bottom.x.to_num::<f32>(),
+            translation.x,
-            translation.y + bottom.y.to_num::<f32>(),
+            translation.y,
             0.0,
         );
 
-        if hitstop_shake.remaining_frames > 0 && hitstop_shake.total_frames > 0 && !game_settings.fighter_common.visual_shake_table.is_empty() {
+        if hitstop_shake.remaining_frames > 0
+            && hitstop_shake.total_frames > 0
+            && !game_settings.fighter_common.visual_shake_table.is_empty()
+        {
             let total = hitstop_shake.total_frames as f32;
             let curr = hitstop_shake.remaining_frames as f32;
             let elapsed = 1.0 - curr / total;
 
-            
+            let access_index = (hitstop_shake.remaining_frames as usize)
-            let access_index = (hitstop_shake.remaining_frames as usize) % game_settings.fighter_common.visual_shake_table.len();
+                % game_settings.fighter_common.visual_shake_table.len();
             let shake_multiplier = match hitstop_shake.role {
-                super::FighterHitstopShakeRole::Attacker => game_settings.fighter_common.attacker_visual_shake_multiplier,
+                super::FighterHitstopShakeRole::Attacker => {
+                    game_settings
+                        .fighter_common
+                        .attacker_visual_shake_multiplier
+                }
                 super::FighterHitstopShakeRole::Receiver => 1.0,
             };
-            let shake_amount: f32 = 1.0 - EaseFunction::QuinticIn.sample(elapsed).unwrap_or_default();
+            let shake_amount: f32 =
-            let shake_amount = game_settings.fighter_common.visual_shake_table[access_index] * shake_amount * shake_multiplier;
+                1.0 - EaseFunction::QuinticIn.sample(elapsed).unwrap_or_default();
+            let shake_amount = game_settings.fighter_common.visual_shake_table[access_index]
+                * shake_amount
+                * shake_multiplier;
 
             let shake_offset = match hitstop_shake.kind {
                 super::FighterHitstopShakeKind::Horizontal => Vec3::new(shake_amount, 0.0, 0.0),
@@ -164,6 +196,19 @@ mod tests {
         assert_eq!(position, Vec2::new(7.0, 14.0));
     }
 
+    #[test]
+    fn presentation_translation_uses_current_sample_after_snap() {
+        let position = sample_presentation_translation_with_snap(
+            FighterPreviousTranslation(FGVec2::new(FGi32::lit("2"), FGi32::lit("4"))),
+            FighterTranslation(FGVec2::new(FGi32::lit("6"), FGi32::lit("12"))),
+            0.25,
+            PresentationMotionMode::Extrapolation,
+            FighterPresentationSnap(true),
+        );
+
+        assert_eq!(position, Vec2::new(6.0, 12.0));
+    }
+
     #[test]
     fn snapshot_fighter_motion_copies_current_world_state() {
         let mut world = World::new();

src/fighter/push.rs

@@ -0,0 +1,214 @@
+//! fighter-to-fighter pushing
+
+use bevy::prelude::*;
+
+use crate::{
+    fighter::{
+        Fighter, FighterFacingDirection, FighterRoster, FighterSurfaceState, FighterTranslation,
+        manifest::FighterManifest,
+    },
+    game_settings::GameSettings,
+    math::int::FGi32,
+    stage::line::{StageCollision, StageLineID, StagePoly},
+};
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+struct Pushbox {
+    center: FGi32,
+    radius: FGi32,
+    line_id: StageLineID,
+}
+
+fn can_interact(stage: &StageCollision, first: StageLineID, second: StageLineID) -> bool {
+    if first.polygon != second.polygon {
+        return false;
+    }
+    if first.segment == second.segment {
+        return true;
+    }
+
+    let Some(poly) = stage.stage_polys.get(first.polygon) else {
+        return false;
+    };
+    adjacent_segment(poly, first.segment, second.segment)
+}
+
+fn adjacent_segment(poly: &StagePoly, first: usize, second: usize) -> bool {
+    poly.get_next_segment_index(first) == Some(second)
+        || poly.get_prev_segment_index(first) == Some(second)
+}
+
+fn push_delta(first: Pushbox, second: Pushbox, nudge: FGi32) -> FGi32 {
+    if (first.center - second.center).abs() >= first.radius + second.radius {
+        return FGi32::ZERO;
+    }
+    (first.center - second.center).signum() * nudge
+}
+
+fn calculate_push_deltas(
+    pushboxes: &[Option<Pushbox>],
+    stage: &StageCollision,
+    nudge: FGi32,
+) -> Vec<FGi32> {
+    let mut deltas = vec![FGi32::ZERO; pushboxes.len()];
+    for first in 0..pushboxes.len() {
+        let Some(first_pushbox) = pushboxes[first] else {
+            continue;
+        };
+        for second in 0..pushboxes.len() {
+            if first == second {
+                continue;
+            }
+            let Some(second_pushbox) = pushboxes[second] else {
+                continue;
+            };
+            if can_interact(stage, first_pushbox.line_id, second_pushbox.line_id) {
+                deltas[first] += push_delta(first_pushbox, second_pushbox, nudge);
+            }
+        }
+    }
+    deltas
+}
+
+pub fn apply_grounded_pushes(
+    roster: Res<FighterRoster>,
+    mut fighters: Query<(
+        &Fighter,
+        &mut FighterTranslation,
+        &FighterFacingDirection,
+        &FighterSurfaceState,
+    )>,
+    manifests: Res<Assets<FighterManifest>>,
+    settings: Res<GameSettings>,
+    stage: Res<StageCollision>,
+) {
+    let pushboxes = roster
+        .0
+        .iter()
+        .map(|entity| {
+            let Ok((fighter, translation, facing, surface)) = fighters.get(*entity) else {
+                return None;
+            };
+            let Some(line_id) = surface.line_id() else {
+                return None;
+            };
+            let manifest = manifests.get(&fighter.manifest)?;
+            let attributes = &manifest.attributes;
+            Some(Pushbox {
+                center: translation.x + facing.to_sign() * attributes.pushbox_offset,
+                radius: attributes.pushbox_radius,
+                line_id,
+            })
+        })
+        .collect::<Vec<_>>();
+    let deltas = calculate_push_deltas(
+        &pushboxes,
+        &stage,
+        settings.fighter_common.grounded_push_nudge,
+    );
+
+    for (entity, delta) in roster.0.iter().zip(deltas) {
+        if delta == FGi32::ZERO {
+            continue;
+        }
+        if let Ok((_, mut translation, _, _)) = fighters.get_mut(*entity) {
+            translation.x += delta;
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::math::vec::FGVec2;
+    use crate::stage::line::{StagePolyLineSegmentType, StagePolyType};
+
+    fn stage() -> StageCollision {
+        StageCollision {
+            stage_polys: vec![StagePoly::build(
+                StagePolyType::Platform,
+                &[
+                    (FGVec2::lit("0", "0"), StagePolyLineSegmentType::Floor),
+                    (FGVec2::lit("10", "0"), StagePolyLineSegmentType::Floor),
+                    (FGVec2::lit("20", "0"), StagePolyLineSegmentType::Floor),
+                    (FGVec2::lit("30", "0"), StagePolyLineSegmentType::Floor),
+                ],
+            )],
+            ..StageCollision::default()
+        }
+    }
+
+    fn box_at(x: &str, segment: usize) -> Pushbox {
+        Pushbox {
+            center: FGi32::lit(x),
+            radius: FGi32::lit("1"),
+            line_id: StageLineID {
+                polygon: 0,
+                segment,
+            },
+        }
+    }
+
+    #[test]
+    fn overlapping_pair_gets_opposite_fixed_nudges() {
+        let deltas = calculate_push_deltas(
+            &[Some(box_at("0", 0)), Some(box_at("1", 0))],
+            &stage(),
+            FGi32::lit("0.3"),
+        );
+        assert_eq!(deltas, vec![FGi32::lit("-0.3"), FGi32::lit("0.3")]);
+    }
+
+    #[test]
+    fn touching_pushboxes_do_not_nudge() {
+        let deltas = calculate_push_deltas(
+            &[Some(box_at("0", 0)), Some(box_at("2", 0))],
+            &stage(),
+            FGi32::lit("0.3"),
+        );
+        assert_eq!(deltas, vec![FGi32::ZERO, FGi32::ZERO]);
+    }
+
+    #[test]
+    fn adjacent_segments_can_push_and_unrelated_segments_cannot() {
+        let adjacent = calculate_push_deltas(
+            &[Some(box_at("9.5", 0)), Some(box_at("10", 1))],
+            &stage(),
+            FGi32::lit("0.3"),
+        );
+        assert_eq!(adjacent, vec![FGi32::lit("-0.3"), FGi32::lit("0.3")]);
+
+        let unrelated = calculate_push_deltas(
+            &[Some(box_at("1", 0)), Some(box_at("2", 2))],
+            &stage(),
+            FGi32::lit("0.3"),
+        );
+        assert_eq!(unrelated, vec![FGi32::ZERO, FGi32::ZERO]);
+    }
+
+    #[test]
+    fn multiple_overlaps_accumulate() {
+        let deltas = calculate_push_deltas(
+            &[
+                Some(box_at("0", 0)),
+                Some(box_at("0.5", 0)),
+                Some(box_at("1", 0)),
+            ],
+            &stage(),
+            FGi32::lit("0.3"),
+        );
+        assert_eq!(
+            deltas,
+            vec![FGi32::lit("-0.6"), FGi32::ZERO, FGi32::lit("0.6")]
+        );
+    }
+
+    #[test]
+    fn system_parameters_initialize_without_query_conflicts() {
+        let mut world = World::new();
+        let mut schedule = Schedule::default();
+        schedule.add_systems(apply_grounded_pushes);
+
+        schedule.initialize(&mut world).unwrap();
+    }
+}

src/fighter/state/air.rs

@@ -1,6 +1,9 @@
-use crate::fighter::state::ground::GroundedStateCommon;
+use crate::fighter::state::jump::{self};
 use crate::fighter::state::land::{LandingState, LandingType};
-use crate::fighter::state::{CollisionContext, FighterState};
+use crate::fighter::state::ledge_grab::LedgeGrabState;
+use crate::fighter::state::{
+    CollisionContext, FighterState, InterruptContext, air_attack, air_dodge,
+};
 use crate::fighter::*;
 use crate::input::FighterCommands;
 
@@ -30,7 +33,7 @@ pub fn process_fast_fall(
 pub fn integrate_gravity(
     velocity: &mut FighterVelocity,
     attributes: &FighterAttributes,
-    fast_fall: bool
+    fast_fall: bool,
 ) {
     velocity.y -= attributes.gravity;
 
@@ -90,29 +93,70 @@ pub fn apply_air_motion(
     translation.0 += velocity.0;
 }
 
+/// Applies ordinary and launch velocity together, then advances launch decay.
+/// Hitstop skips state updates entirely, so neither decay nor launch age moves
+/// while the fighter is frozen.
+pub fn apply_air_motion_with_knockback(ctx: &mut crate::fighter::state::UpdateContext) {
+    let combined_velocity = FighterVelocity(ctx.velocity.0 + ctx.knockback_velocity.0);
+    apply_air_motion(&combined_velocity, ctx.translation, ctx.prev_translation);
+    attack::decay_knockback(
+        ctx.knockback_velocity,
+        ctx.knockback_state,
+        ctx.game_settings.fighter_common.knockback_decay_per_frame,
+    );
+}
+
 pub fn update_standard_motion(
     ctx: &mut crate::fighter::state::UpdateContext,
     airborne_common: &mut AirborneStateCommon,
 ) {
-    process_fast_fall(airborne_common, ctx.input, &mut ctx.velocity, ctx.fighter_attributes);
+    process_fast_fall(
-    integrate_gravity(ctx.velocity, ctx.fighter_attributes, airborne_common.is_fast_falling);
+        airborne_common,
+        ctx.input,
+        &mut ctx.velocity,
+        ctx.fighter_attributes,
+    );
+    integrate_gravity(
+        ctx.velocity,
+        ctx.fighter_attributes,
+        airborne_common.is_fast_falling,
+    );
     apply_air_drift(ctx.velocity, ctx.fighter_attributes, ctx.input);
-    apply_air_motion(ctx.velocity, ctx.translation, ctx.prev_translation);
+    apply_air_motion_with_knockback(ctx);
+}
+
+pub fn air_interrupts_common(
+    ctx: &mut InterruptContext,
+    airborne_state_common: &AirborneStateCommon,
+) -> Option<FighterState> {
+    jump::check_input_double_jump(ctx).or_else(|| {
+        air_dodge::check_input(ctx)
+            .or_else(|| air_attack::check_interrupt(ctx, airborne_state_common))
+    })
 }
 
 pub fn collision_interrupt(
     ctx: &mut CollisionContext,
     landing_type: LandingType,
+    options: crate::fighter::collision::AirCollisionOptions,
 ) -> Option<FighterState> {
-    let res = ctx.air_collide_with_stage()?;
+    if ctx.velocity.y <= FGi32::ZERO {
-    ctx.translation.0 = res.hit_position - ctx.ecb.get_bottom_point();
+        if let Some(ledge_result) = ctx.air_collide_with_ledges() {
-    let grounded_common = GroundedStateCommon {
+            ctx.apply_desired_ecb();
-        current_line_id: res.line_id,
+            return Some(FighterState::LedgeGrab(LedgeGrabState::new(ledge_result.ledge)));
-    };
+        }
-    Some(FighterState::Land(LandingState::create(
+    }
-        grounded_common,
+
-        landing_type,
+    let res = ctx.air_collide_with_stage(options)?;
-    )))
+    ctx.translation.0 = res.resolved_translation;
+    let bottom_offset = ctx.ecb.rebase_onto_bottom();
+    ctx.translation.0 += bottom_offset;
+    *ctx.desired_ecb = crate::fighter::ecb::FighterDesiredECB::from(*ctx.ecb);
+    ctx.presentation_snap.0 = true;
+    ctx.surface.land(res.line_id, ctx.ledge_info);
+    ctx.knockback_velocity.0 = FGVec2::ZERO;
+    ctx.knockback_state.clear();
+    Some(FighterState::Land(LandingState::create(landing_type)))
 }
 
 #[cfg(test)]
@@ -125,6 +169,8 @@ mod tests {
 
     fn test_attributes() -> FighterAttributes {
         FighterAttributes {
+            pushbox_offset: FGi32::ZERO,
+            pushbox_radius: FGi32::ONE,
             base_walk_accel: FGi32::ZERO,
             stick_walk_accel: FGi32::ZERO,
             max_walk_vel: FGi32::ZERO,
@@ -155,6 +201,9 @@ mod tests {
             air_dodge_duration: 0,
             air_dodge_velocity: FGi32::ZERO,
             air_dodge_decay: FGi32::ZERO,
+            air_dodge_intangible_duration: 29,
+            air_dodge_intangible_start: 4,
+            dash_attack_cancel_window: 3,
         }
     }
 

src/fighter/state/air_attack.rs

@@ -0,0 +1,168 @@
+use bevy::log::error;
+
+use crate::fighter::{
+    attack::{AttackKind, FighterAttackScriptAssets, update_active_attack}, state::{
+        CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl, InterruptContext, UpdateContext, air::{self, AirborneStateCommon}, air_attack, fall::FallState, jump,
+    },
+};
+
+#[derive(Clone, Debug, Hash)]
+pub struct AirAttackState {
+    pub attack_kind: AttackKind,
+    pub airborne_state_common: AirborneStateCommon,
+    pub is_in_autocancel_window: bool,
+}
+
+impl FighterStateImpl for AirAttackState {
+    const NAME: &'static str = "AirAttack";
+
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        let animation_frame = state_context.get_current_animation_frame();
+        let script = state_context
+            .attack_scripts
+            .get(&state_context.attack_script_assets.scripts[&self.attack_kind]);
+        
+        if let Some(script) = script {
+            if let Some(iasa_frame) = script.iasa_frame {
+                if animation_frame >= iasa_frame {
+                    let new_state = jump::check_input_double_jump(state_context).or_else(|| air_attack::check_interrupt(state_context, &self.airborne_state_common));
+                    if let Some(new_state) = new_state {
+                        return Some(new_state);
+                    }
+                }
+            }
+        }
+
+        if state_context.is_current_animation_finished() {
+            Some(FighterState::Fall(FallState::new(
+                self.airborne_state_common,
+            )))
+        } else {
+            None
+        }
+    }
+
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        let animation_frame = state_context.get_current_animation_frame();
+        let script = state_context
+            .attack_scripts
+            .get(&state_context.attack_script_assets.scripts[&self.attack_kind]);
+        if let Some(script) = script {
+            update_active_attack(
+                script,
+                state_context
+                    .hitboxes
+                    .0
+                    .as_mut()
+                    .expect("ground attack must have active hitboxes"),
+                animation_frame,
+            );
+            if let Some((autocancel_start, autocancel_end)) = script.wont_autocancel_window {
+                self.is_in_autocancel_window =
+                    animation_frame < autocancel_start || animation_frame > autocancel_end;
+            }
+        }
+
+        air::update_standard_motion(state_context, &mut self.airborne_state_common);
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context
+            .input
+            .consume_command(crate::input::FighterCommands::Attack);
+        state_context.play_animation(self.attack_kind.get_animation(), false);
+        let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
+        state_context.hitboxes.0 = Some(crate::fighter::FighterActiveAttack {
+            kind: self.attack_kind,
+            script,
+            active_hitboxes: Vec::new(),
+            solved_hitboxes: Vec::new(),
+            hit_groups: Vec::new(),
+            stalled: false,
+        });
+    }
+
+    fn on_exit(&mut self, state_context: &mut ExitContext) {
+        state_context.hitboxes.0 = None;
+    }
+
+    fn check_collision_interrupt(
+        &mut self,
+        state_context: &mut CollisionContext,
+    ) -> Option<FighterState> {
+        let coll_interrupt = air::collision_interrupt(
+            state_context,
+            crate::fighter::state::land::LandingType::Normal,
+            Default::default(),
+        );
+
+        coll_interrupt.map(|state| {
+            if self.is_in_autocancel_window {
+                state
+            } else {
+                // TODO: Implement proper landing lag
+                state
+            }
+        })
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
+        false
+    }
+}
+
+#[derive(thiserror::Error, Debug)]
+pub enum AirAttackStateCreateError {
+    #[error("Attack script: {attack:?} not found")]
+    AttackScriptNotFound { attack: AttackKind },
+}
+
+impl AirAttackState {
+    pub fn create(
+        attack_kind: AttackKind,
+        attack_script_assets: &FighterAttackScriptAssets,
+        airborne_state_common: &AirborneStateCommon,
+    ) -> Result<Self, AirAttackStateCreateError> {
+        if attack_script_assets.scripts.contains_key(&attack_kind) {
+            Ok(AirAttackState {
+                airborne_state_common: airborne_state_common.clone(),
+                attack_kind,
+                is_in_autocancel_window: false,
+            })
+        } else {
+            Err(AirAttackStateCreateError::AttackScriptNotFound {
+                attack: attack_kind,
+            })
+        }
+    }
+}
+
+pub fn check_interrupt(
+    state_context: &InterruptContext,
+    airborne_state_common: &AirborneStateCommon,
+) -> Option<FighterState> {
+    if state_context
+        .input
+        .has_command(crate::input::FighterCommands::Attack)
+    {
+        let attack_kind = state_context
+            .input
+            .get_attack_command_type()
+            .to_attack_kind_airborne(state_context.facing_direction);
+        let state = AirAttackState::create(
+            attack_kind,
+            state_context.attack_script_assets,
+            airborne_state_common,
+        );
+
+        match state {
+            Ok(state) => Some(FighterState::AirAttack(state)),
+            Err(create_error) => {
+                error!("{}", create_error);
+                None
+            }
+        }
+    } else {
+        None
+    }
+}

src/fighter/state/air_dodge.rs

@@ -1,9 +1,9 @@
 use crate::{
     fighter::{
-        animation::AnimKind, state::{
+        FighterInvulnerabilityState, animation::AnimKind, state::{
-            CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext, UpdateContext, air::{self, AirborneStateCommon}, fall::FallState, land::LandingType,
+            CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext, UpdateContext, air::{self, AirborneStateCommon}, fall::FallState, land::{LandingState, LandingType},
         },
-    }, input, math::vec::FGVec2,
+    }, input, math::vec::FGVec2, stage::line::{StageLineID, StagePolyLineSegmentType},
 };
 
 #[derive(Debug, Clone, Hash)]
@@ -16,48 +16,106 @@ impl FighterStateImpl for AirDodgeState {
 
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if state_context.is_current_animation_finished() {
-            Some(FighterState::Fall(FallState::new(AirborneStateCommon::default())))
+            Some(FighterState::Fall(FallState::new(
+                AirborneStateCommon::default(),
+            )))
         } else {
             None
         }
     }
 
     fn update(&mut self, state_context: &mut UpdateContext) {
+        let airdodge_intangible_end = state_context.fighter_attributes.air_dodge_intangible_start + state_context.fighter_attributes.air_dodge_intangible_duration;
+        if state_context.animation_frame == state_context.fighter_attributes.air_dodge_intangible_start {
+            *state_context.vulnerability = FighterInvulnerabilityState::Intangible { frames_remaining: Some(state_context.fighter_attributes.air_dodge_intangible_duration) };
+        } else if state_context.animation_frame >= airdodge_intangible_end {
+            *state_context.vulnerability = FighterInvulnerabilityState::Vulnerable;
+        }
         state_context.velocity.0 *= state_context.fighter_attributes.air_dodge_decay;
 
-        air::apply_air_motion(
+        air::apply_air_motion_with_knockback(state_context);
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
     }
 
     fn check_collision_interrupt(
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        air::collision_interrupt(state_context, LandingType::Special)
+        let can_wavesnap = self.direction.y.is_zero() || self.direction.y.is_negative();
+        
+        if can_wavesnap {
+            for (poly_idx, poly) in state_context.stage_collision.stage_polys.iter().enumerate() {
+                for (segment_idx, segment) in poly.segments.iter().enumerate() {
+                    if !matches!(segment.segment_type, StagePolyLineSegmentType::Floor) {
+                        continue;
+                    }
+                    let bottom_point = state_context.translation.0 + state_context.ecb.get_bottom_point();
+                    let point_in_segment = segment.segment.closest_point(bottom_point);
+                    let dist_to_segment = point_in_segment.distance(bottom_point);
+                    if dist_to_segment <= state_context.waveland_snap_distance {
+                        state_context.ecb.bottom = point_in_segment - state_context.translation.0;
+                        state_context.ecb.rebase_onto_bottom();
+                        state_context.surface.land(StageLineID { polygon: poly_idx, segment: segment_idx }, state_context.ledge_info);
+                        state_context.knockback_velocity.0 = FGVec2::ZERO;
+                        state_context.knockback_state.clear();
+                        return Some(FighterState::Land(LandingState::create(LandingType::Special)));
+                    }
+                }
+            }
+        }
+
+        air::collision_interrupt(
+            state_context,
+            LandingType::Special,
+            crate::fighter::collision::AirCollisionOptions {
+                land_on_soft_platforms_from_below: true,
+                ..Default::default()
+            },
+        )
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::AirDodge, false);
 
+        state_context
+            .input
+            .clear_command(input::FighterCommands::Shield);
+        state_context
+            .input
+            .clear_command(input::FighterCommands::GuardHold);
+
         state_context.velocity.0 =
             self.direction * state_context.fighter_attributes.air_dodge_velocity;
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         false
     }
+
+    fn surface_policy(&self) -> super::SurfacePolicy {
+        super::SurfacePolicy::Airborne(crate::fighter::surface::EcbLockPolicy::StartOnDetach)
+    }
+
+    fn on_exit(&mut self, state_context: &mut super::ExitContext) {
+        *state_context.vulnerability = FighterInvulnerabilityState::Vulnerable;
+    }
+
+    fn name(&self) -> String {
+        Self::NAME.to_owned()
+    }
 }
 
 pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
     state_context
         .input
         .has_command(input::FighterCommands::Shield)
-        .then(|| {
+        .then_some(())
+        .or_else(|| {
+            state_context
+                .input
+                .has_command(input::FighterCommands::GuardHold)
+                .then_some(())
+        })
+        .map(|_| {
             FighterState::AirDodge(AirDodgeState {
                 direction: state_context
                     .input

src/fighter/state/angel.rs

@@ -0,0 +1,55 @@
+use crate::{fighter::{FighterInvulnerabilityState, animation::AnimKind, state::{FighterState, FighterStateImpl, air::AirborneStateCommon, fall::FallState}}, math::vec::FGVec2};
+
+#[derive(Debug, Clone, Hash)]
+pub struct AngelState {
+    frames_remaining: u32
+}
+
+impl AngelState {
+    pub fn new(duration: u32) -> Self {
+        Self {
+            frames_remaining: duration
+        }
+    }
+}
+
+impl FighterStateImpl for AngelState {
+    const NAME: &'static str = "Angel";
+
+    fn check_interrupt(&self, state_context: &mut super::InterruptContext) -> Option<super::FighterState> {
+        let moved_sideways = !state_context.input.get_last_frame().movement.x.is_zero();
+        let moved_vertically = !state_context.input.get_last_frame().movement.y.is_zero();
+
+        if self.frames_remaining == 0 || moved_sideways || moved_vertically {
+            Some(FighterState::Fall(FallState::new(AirborneStateCommon::default())))
+        } else {
+            None
+        }
+    }
+
+    fn update(&mut self, _state_context: &mut super::UpdateContext) {
+        self.frames_remaining = self.frames_remaining.saturating_sub(1);
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
+        false
+    }
+    
+    fn on_enter(&mut self, state_context: &mut super::EnterContext) {
+        state_context.play_animation(AnimKind::Wait, true);
+        state_context.velocity.0 = FGVec2::ZERO;
+        *state_context.vulnerability = FighterInvulnerabilityState::Invulnerable { frames_remaining: Some(state_context.game_settings.fighter_common.angel_platform_invulnerability_duration) };
+    }
+    
+    fn check_collision_interrupt(
+        &mut self,
+        state_context: &mut super::CollisionContext,
+    ) -> Option<super::FighterState> {
+        state_context.apply_desired_ecb();
+        None
+    }
+    
+    fn surface_policy(&self) -> super::SurfacePolicy {
+        super::SurfacePolicy::Airborne(crate::fighter::surface::EcbLockPolicy::Clear)
+    }
+}

src/fighter/state/crouch.rs

@@ -0,0 +1,169 @@
+use super::{
+    CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext, ground,
+};
+use crate::fighter::FighterSurfaceState;
+use crate::fighter::animation::AnimKind;
+use crate::fighter::state::air::AirborneStateCommon;
+use crate::fighter::state::ground::{
+    grounded_movement_common_interrupts, grounded_movement_standstill_common_interrupts,
+};
+use crate::fighter::state::platform_pass::PlatformPassState;
+use crate::fighter::state::{FighterState, dash, ground_attack, turn, walk};
+use crate::input::FighterCommands;
+use crate::stage::line::StagePolyType;
+
+#[derive(Debug, Clone, Hash)]
+pub enum CrouchSubState {
+    Entering { pass_queued: bool },
+    Idle,
+    Exiting,
+}
+
+#[derive(Debug, Clone, Hash)]
+pub struct CrouchState {
+    sub_state: CrouchSubState,
+}
+
+pub fn crouch_idle_interrupts(state_context: &InterruptContext) -> Option<FighterState> {
+    if let Some(state) = ground_attack::check_interrupt(state_context) {
+        Some(state)
+    } else if let Some(state) = dash::check_input(state_context) {
+        Some(state)
+    } else if let Some(state) = turn::check_input(state_context) {
+        Some(state)
+    } else if let Some(state) = walk::check_input(state_context) {
+        Some(state)
+    } else {
+        None
+    }
+}
+
+pub fn crouch_entering_interrupts(state_context: &InterruptContext) -> Option<FighterState> {
+    if let Some(state) = ground_attack::check_interrupt(state_context) {
+        Some(state)
+    } else {
+        None
+    }
+}
+
+impl FighterStateImpl for CrouchState {
+    const NAME: &'static str = "Crouch";
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        if let Some(state) = grounded_movement_common_interrupts(state_context) {
+            return Some(state);
+        }
+
+        match self.sub_state {
+            CrouchSubState::Entering { pass_queued } => {
+                // pass
+                if let FighterSurfaceState::Grounded { line_id } = state_context.surface {
+                    if let Some(stage_poly) = state_context
+                        .stage_collision
+                        .stage_polys
+                        .get(line_id.polygon)
+                    {
+                        let is_inputting_crouch = -state_context.game_settings.input_common.run_stick_threshold > state_context.input.get_last_frame().movement.y;
+                        let is_on_a_soft_platform = matches!(stage_poly.poly_type, StagePolyType::Platform);
+                        if pass_queued && is_inputting_crouch && is_on_a_soft_platform 
+                        {
+                            return Some(FighterState::PlatformPass(PlatformPassState::new(
+                                AirborneStateCommon::default(),
+                                line_id.polygon,
+                            )));
+                        }
+                    }
+                }
+
+                // While entering the crouch animation we do not allow movement inputs, but we do allow attacks and jumps
+                if state_context.is_current_animation_finished() {
+                    return Some(FighterState::Crouch(CrouchState {
+                        sub_state: CrouchSubState::Idle,
+                    }));
+                } else {
+                    return crouch_entering_interrupts(state_context);
+                }
+            }
+            CrouchSubState::Idle => {
+                if state_context.input.get_last_frame().movement.y
+                    > -state_context.game_settings.input_common.run_stick_threshold
+                {
+                    return Some(FighterState::Crouch(CrouchState {
+                        sub_state: CrouchSubState::Exiting,
+                    }));
+                } else {
+                    return crouch_idle_interrupts(state_context);
+                }
+            }
+            CrouchSubState::Exiting => {
+                if state_context.is_current_animation_finished() {
+                    return grounded_movement_standstill_common_interrupts(state_context);
+                } else {
+                    return crouch_idle_interrupts(state_context);
+                }
+            }
+        }
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        match self.sub_state {
+            CrouchSubState::Entering { .. } => {
+                state_context.play_animation(AnimKind::CrouchEnter, false);
+            }
+            CrouchSubState::Idle => {
+                state_context.play_animation(AnimKind::CrouchIdle, true);
+            }
+            CrouchSubState::Exiting => {
+                state_context.play_animation(AnimKind::CrouchExit, false);
+            }
+        }
+    }
+
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        if let CrouchSubState::Entering {
+            pass_queued,
+        } = &mut self.sub_state
+        {
+            if state_context
+                .input
+                .has_command(FighterCommands::SmashMoveDown)
+            {
+                state_context
+                    .input
+                    .clear_command(FighterCommands::SmashMoveDown);
+                *pass_queued = true;
+            }
+        }
+        ground::update_friction_motion(state_context);
+    }
+
+    fn check_collision_interrupt(
+        &mut self,
+        state_context: &mut CollisionContext,
+    ) -> Option<FighterState> {
+        ground::collision_interrupt(state_context, false)
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
+        true
+    }
+}
+
+impl CrouchState {
+    pub fn is_crouch_cancelling(&self) -> bool {
+        match self.sub_state {
+            CrouchSubState::Entering { .. } | CrouchSubState::Idle => true,
+            CrouchSubState::Exiting => false,
+        }
+    }
+}
+
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
+    let input_frame = state_context.input.get_last_frame();
+
+    if input_frame.movement.y <= -state_context.game_settings.input_common.run_stick_threshold {
+        return Some(FighterState::Crouch(CrouchState {
+            sub_state: CrouchSubState::Entering { pass_queued: false },
+        }));
+    }
+    None
+}

src/fighter/state/dash.rs

@@ -4,53 +4,54 @@ use super::{
 };
 use crate::fighter::FighterFacingDirection;
 use crate::fighter::animation::AnimKind;
-use crate::fighter::state::FighterState;
+use crate::fighter::state::{FighterState, ground_attack};
-use crate::fighter::state::ground::GroundedStateCommon;
 use crate::input::FighterCommands::{SmashMoveLeft, SmashMoveRight};
 
 #[derive(Debug, Clone, Hash)]
 pub struct DashState {
     direction: FighterFacingDirection,
-    pub ground_common: GroundedStateCommon,
 }
 
 impl DashState {
-    pub fn new(direction: FighterFacingDirection, ground_common: GroundedStateCommon) -> Self {
+    pub fn new(direction: FighterFacingDirection) -> Self {
-        Self {
+        Self { direction }
-            direction,
-            ground_common,
-        }
     }
 }
 
 impl FighterStateImpl for DashState {
     const NAME: &'static str = "Dash";
     fn check_interrupt(&self, ctx: &mut InterruptContext) -> Option<FighterState> {
-        let ground = &self.ground_common;
         let attributes = ctx.fighter_attributes;
 
+        if ctx.get_current_animation_frame() <= 2 || ctx.input.get_last_frame().movement.x.signum() != self.direction.to_sign() {
+            if let Some(state) = ground_attack::check_interrupt(ctx) {
+                return Some(state);
+            }
+        } else {
+            if let Some(state) = ground_attack::check_interrupt_dash_attack(ctx) {
+                return Some(state);
+            }
+        }
+
         // A reverse dash can interrupt before IASA
         if let Some(direction) =
             check_smash_input_with_dir(ctx).filter(|direction| *direction != self.direction)
         {
-            return Some(FighterState::Dash(DashState::new(
+            return Some(FighterState::Dash(DashState::new(direction)));
-                direction,
-                ground.clone(),
-            )));
         }
 
-        if let Some(state) = ground::grounded_movement_common_interrupts(ctx, ground) {
+        if let Some(state) = ground::grounded_movement_common_interrupts(ctx) {
             return Some(state);
         }
 
         if ctx.is_current_animation_finished() {
-            return run::check_input(ctx, ground)
+            return run::check_input(ctx)
-                .or_else(|| walk::check_input(ctx, ground))
+                .or_else(|| walk::check_input(ctx))
-                .or_else(|| wait::check_input(ctx, ground));
+                .or_else(|| wait::check_input(ctx));
         }
 
         if ctx.get_current_animation_frame() > attributes.dash_acceleration_duration {
-            return run::check_input(ctx, ground);
+            return run::check_input(ctx);
         }
 
         None
@@ -98,7 +99,6 @@ impl FighterStateImpl for DashState {
         ground::apply_grounded_motion(
             state_context.velocity,
             state_context.translation,
-            state_context.prev_translation,
         );
     }
 
@@ -106,12 +106,10 @@ impl FighterStateImpl for DashState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.ground_common, true)
+        ground::collision_interrupt(state_context, true)
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }
@@ -126,10 +124,6 @@ fn check_smash_input_with_dir(state_context: &InterruptContext) -> Option<Fighte
     }
 }
 
-pub fn check_input(
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context: &InterruptContext,
+    check_smash_input_with_dir(state_context).map(|dir| FighterState::Dash(DashState::new(dir)))
-    ground_common: &GroundedStateCommon,
-) -> Option<FighterState> {
-    check_smash_input_with_dir(state_context)
-        .map(|dir| FighterState::Dash(DashState::new(dir, ground_common.clone())))
 }

src/fighter/state/fall.rs

@@ -1,7 +1,7 @@
 use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::air::AirborneStateCommon;
-use crate::fighter::state::{FighterState, air, jump};
+use crate::fighter::state::{FighterState, air, air_attack, jump};
 
 #[derive(Debug, Clone, Copy, Hash, Default)]
 pub struct FallState {
@@ -20,11 +20,12 @@ impl FighterStateImpl for FallState {
     const NAME: &'static str = "Fall";
     
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
-        jump::check_input_double_jump(state_context)
+        jump::check_input_double_jump(state_context).or_else(|| air_attack::check_interrupt(state_context, &self.airborne_state_common))
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::Fall, true);
+        state_context.velocity.x = state_context.velocity.x.clamp(-state_context.fighter_attributes.air_drift_max, state_context.fighter_attributes.air_drift_max);
     }
 
     fn update(&mut self, state_context: &mut UpdateContext) {
@@ -38,6 +39,10 @@ impl FighterStateImpl for FallState {
         air::collision_interrupt(
             state_context,
             crate::fighter::state::land::LandingType::Normal,
+            crate::fighter::collision::AirCollisionOptions {
+                can_pass_through_soft_platforms: true,
+                ..Default::default()
+            },
         )
     }
     
@@ -46,5 +51,8 @@ impl FighterStateImpl for FallState {
     ) -> bool {
         false
     }
-}
 
+    fn surface_policy(&self) -> super::SurfacePolicy {
+        super::SurfacePolicy::Airborne(crate::fighter::surface::EcbLockPolicy::StartOnDetach)
+    }
+}

src/fighter/state/ground.rs

@@ -2,23 +2,20 @@
 //! ECS types so it stays cheap to reason about and to unit-test — it has to be
 //! bit-for-bit deterministic for rollback.
 
+use crate::fighter::state::air_dodge::AirDodgeState;
 use crate::fighter::state::{
-    CollisionContext, FighterState, InterruptContext, air, dash, fall, ground_attack, turn, wait, walk,
+    CollisionContext, FighterState, InterruptContext, air, crouch, dash, fall, ground_attack, turn,
-};
+    wait, walk,
-use crate::fighter::{
-    FighterAttributes, FighterPreviousTranslation, FighterTranslation, FighterVelocity,
 };
+use crate::fighter::{collision, ecb};
+use crate::fighter::{FighterAttributes, FighterTranslation, FighterVelocity};
 use crate::game_settings::GameSettings;
+use crate::input::FighterInput;
 use crate::math::int::{FGWide, FGi32};
 use crate::math::vec::FGVec2;
-use crate::stage::line::{StageLineID, StagePoly, StagePolyLineSegment, StagePolyLineSegmentType};
+use crate::stage::line::{StagePoly, StagePolyLineSegment, StagePolyLineSegmentType};
-
+#[cfg(test)]
-use bevy::prelude::*;
+use crate::stage::line::StageLineID;
-
-#[derive(Reflect, Hash, Clone, Debug)]
-pub struct GroundedStateCommon {
-    pub current_line_id: StageLineID,
-}
 
 pub fn apply_grounded_friction(friction: FGi32, ground_vel: FGi32) -> FGi32 {
     if friction.abs() > ground_vel.abs() {
@@ -153,13 +150,8 @@ fn resolve_grounded_position(
     GroundedPositionResult::InAir
 }
 
-pub fn apply_grounded_motion(
+pub fn apply_grounded_motion(velocity: &FighterVelocity, translation: &mut FighterTranslation) {
-    velocity: &FighterVelocity,
-    translation: &mut FighterTranslation,
-    prev_translation: &mut FighterPreviousTranslation,
-) {
     // Vertical velocity should be 0 on the ground
-    prev_translation.0 = translation.0;
     translation.0 += FGVec2::new(velocity.0.x, FGi32::ZERO);
 }
 
@@ -176,70 +168,105 @@ pub fn update_friction_motion(ctx: &mut crate::fighter::state::UpdateContext) {
 
     let ground_velocity = ctx.velocity.x;
     ctx.velocity.x += apply_grounded_friction(friction, ground_velocity);
-    apply_grounded_motion(ctx.velocity, ctx.translation, ctx.prev_translation);
+    apply_grounded_motion(ctx.velocity, ctx.translation);
 }
 
 pub fn collide_with_stage_grounded(
     state_context: &mut CollisionContext,
-    ground_common: &mut GroundedStateCommon,
     can_walk_off: bool,
 ) -> GroundedMotionResult {
-    let translation = &mut state_context.translation;
+    let Some(mut line_id) = state_context.surface.line_id() else {
-    let ecb = state_context.ecb;
+        state_context.apply_desired_ecb();
-    let stage_collision = state_context.stage_collision;
+        return GroundedMotionResult::InAir;
+    };
+    let requested_translation = state_context.translation.0;
+    let movement = requested_translation - state_context.prev_translation.0;
+    let largest_change = movement
+        .x
+        .abs()
+        .max(movement.y.abs())
+        .max(ecb::ecb_max_delta(state_context.ecb, state_context.desired_ecb));
+    let steps = collision::collision_step_count(largest_change);
+    let movement_per_step = movement / FGi32::from_num(steps);
+    let mut current_position = state_context.prev_translation.0;
+    let mut current_ecb = *state_context.ecb;
 
-    let stage_poly = stage_collision
+    for step in 0..steps {
-        .stage_polys
+        ecb::interpolate_ecb(
-        .get(ground_common.current_line_id.polygon);
+            &mut current_ecb,
+            *state_context.desired_ecb,
+            FGi32::ONE / FGi32::from_num(steps - step),
+        );
+        current_position = if step + 1 == steps {
+            requested_translation
+        } else {
+            state_context.prev_translation.0
+                + movement_per_step * FGi32::from_num(step + 1)
+        };
 
-    if let Some(stage_poly) = stage_poly {
+        let Some(stage_poly) = state_context.stage_collision.stage_polys.get(line_id.polygon) else {
-        let ecb_bottom_pos = translation.0 + ecb.get_bottom_point();
+            *state_context.ecb = current_ecb;
+            state_context.translation.0 = current_position;
+            state_context.surface.apply_airborne_policy(
+                crate::fighter::surface::EcbLockPolicy::StartOnDetach,
+                state_context.leave_ground_ecb_lock_duration,
+            );
+            return GroundedMotionResult::InAir;
+        };
         match resolve_grounded_position(
             stage_poly,
-            ground_common.current_line_id.segment,
+            line_id.segment,
-            ecb_bottom_pos,
+            current_position + current_ecb.bottom,
             can_walk_off,
         ) {
-            GroundedPositionResult::InGround {
+            GroundedPositionResult::InGround { point, segment_idx, blocked } => {
-                point,
+                line_id.segment = segment_idx;
-                segment_idx,
+                current_position = point - current_ecb.bottom;
-                blocked,
+                let segment = stage_poly.get_segment(segment_idx).unwrap();
-            } => {
-                let current_segment = stage_poly.get_segment(segment_idx).unwrap();
-                translation.0 = point - ecb.get_bottom_point();
                 state_context.velocity.0 = if blocked {
                     FGVec2::ZERO
                 } else {
                     state_context.velocity.0
-                        - state_context
+                        - state_context.velocity.0.project_onto_normalized(segment.normal)
-                            .velocity
-                            .0
-                            .project_onto_normalized(current_segment.normal)
                 };
-                ground_common.current_line_id.segment = segment_idx;
-                GroundedMotionResult::InGround
             }
-            GroundedPositionResult::InAir => GroundedMotionResult::InAir,
+            GroundedPositionResult::InAir => {
+                *state_context.ecb = current_ecb;
+                state_context.translation.0 = current_position;
+                state_context.surface.apply_airborne_policy(
+                    crate::fighter::surface::EcbLockPolicy::StartOnDetach,
+                    state_context.leave_ground_ecb_lock_duration,
+                );
+                return GroundedMotionResult::InAir;
+            }
         }
-    } else {
-        GroundedMotionResult::InAir
     }
+
+    *state_context.ecb = current_ecb;
+    state_context.translation.0 = current_position;
+    state_context.surface.land(line_id, state_context.ledge_info);
+    GroundedMotionResult::InGround
 }
 
-pub fn collision_interrupt(
+pub fn collision_interrupt(ctx: &mut CollisionContext, can_walk_off: bool) -> Option<FighterState> {
-    ctx: &mut CollisionContext,
+    match collide_with_stage_grounded(ctx, can_walk_off) {
-    common: &mut GroundedStateCommon,
-    can_walk_off: bool,
-) -> Option<FighterState> {
-    match collide_with_stage_grounded(ctx, common, can_walk_off) {
         GroundedMotionResult::InGround => None,
-        GroundedMotionResult::InAir => Some(FighterState::Fall(fall::FallState::new(air::AirborneStateCommon::default()))),
+        GroundedMotionResult::InAir => Some(FighterState::Fall(fall::FallState::new(
+            air::AirborneStateCommon::default(),
+        ))),
     }
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::fighter::attack::{FighterKnockbackState, FighterKnockbackVelocity};
+    use crate::fighter::ecb::{FighterDesiredECB, FighterPreviousECB};
+    use crate::fighter::{
+        FighterECB, FighterLedgeInformation, FighterPreviousTranslation, FighterSurfaceState,
+    };
+    use crate::input::FighterInput;
+    use crate::math::rect::FGRect;
     use crate::stage::line::StagePolyType;
 
     fn two_segment_floor() -> StagePoly {
@@ -346,30 +373,175 @@ mod tests {
             GroundedPositionResult::InAir
         ));
     }
+
+    #[test]
+    fn grounded_collision_updates_surface_segment() {
+        let stage_collision = crate::stage::line::StageCollision {
+            stage_polys: vec![two_segment_floor()],
+            ..crate::stage::line::StageCollision::default()
+        };
+        let mut surface = FighterSurfaceState::Grounded {
+            line_id: StageLineID {
+                polygon: 0,
+                segment: 0,
+            },
+        };
+        let mut translation = FighterTranslation(FGVec2::lit("11", "0"));
+        let previous_translation = FighterPreviousTranslation(translation.0);
+        let mut velocity = FighterVelocity::default();
+        let mut knockback_velocity = FighterKnockbackVelocity::default();
+        let mut knockback_state = FighterKnockbackState::default();
+        let mut ledge_info = FighterLedgeInformation::default();
+        let mut ecb = FighterECB {
+            bottom: FGVec2::lit("0.0", "-0.5"),
+            top: FGVec2::lit("0.0", "0.5"),
+            left: FGVec2::lit("-0.5", "0.0"),
+            right: FGVec2::lit("0.5", "0.0"),
+        };
+        let previous_ecb = FighterPreviousECB::from(ecb);
+        let mut desired_ecb = FighterDesiredECB::from(ecb);
+        let mut presentation_snap = crate::fighter::FighterPresentationSnap::default();
+        let mut context = CollisionContext {
+            translation: &mut translation,
+            prev_translation: &previous_translation,
+            input: &FighterInput::default(),
+            velocity: &mut velocity,
+            knockback_velocity: &mut knockback_velocity,
+            knockback_state: &mut knockback_state,
+            surface: &mut surface,
+            ecb: &mut ecb,
+            desired_ecb: &mut desired_ecb,
+            ledge_info: &mut ledge_info,
+            prev_ecb: &previous_ecb,
+            stage_collision: &stage_collision,
+            leave_ground_ecb_lock_duration: 10,
+            presentation_snap: &mut presentation_snap,
+            downward_stick_threshold: FGi32::ONE,
+            fighter_ledge_collision_box: FGRect {
+                origin: FGVec2::ZERO,
+                end: FGVec2::ZERO,
+            },
+            waveland_snap_distance: FGi32::ZERO,
+        };
+
+        assert!(matches!(
+            collide_with_stage_grounded(&mut context, true),
+            GroundedMotionResult::InGround
+        ));
+        assert_eq!(
+            surface.line_id(),
+            Some(StageLineID {
+                polygon: 0,
+                segment: 1,
+            })
+        );
+    }
+
+    #[test]
+    fn walking_off_edge_clears_surface_contact() {
+        let stage_collision = crate::stage::line::StageCollision {
+            stage_polys: vec![StagePoly::build(
+                StagePolyType::Platform,
+                &[
+                    (FGVec2::lit("0", "0"), StagePolyLineSegmentType::Floor),
+                    (FGVec2::lit("10", "0"), StagePolyLineSegmentType::Floor),
+                ],
+            )],
+            ..crate::stage::line::StageCollision::default()
+        };
+        let mut surface = FighterSurfaceState::Grounded {
+            line_id: StageLineID {
+                polygon: 0,
+                segment: 0,
+            },
+        };
+        let mut translation = FighterTranslation(FGVec2::lit("11", "0"));
+        let previous_translation = FighterPreviousTranslation(translation.0);
+        let mut velocity = FighterVelocity::default();
+        let mut knockback_velocity = FighterKnockbackVelocity::default();
+        let mut knockback_state = FighterKnockbackState::default();
+        let mut ecb = FighterECB {
+            bottom: FGVec2::lit("0.0", "-0.5"),
+            top: FGVec2::lit("0.0", "0.5"),
+            left: FGVec2::lit("-0.5", "0.0"),
+            right: FGVec2::lit("0.5", "0.0"),
+        };
+        let previous_ecb = FighterPreviousECB::from(ecb);
+        let mut desired_ecb = FighterDesiredECB::from(ecb);
+        let mut presentation_snap = crate::fighter::FighterPresentationSnap::default();
+        let mut ledge_info = FighterLedgeInformation::default();
+        let mut context = CollisionContext {
+            translation: &mut translation,
+            prev_translation: &previous_translation,
+            input: &FighterInput::default(),
+            velocity: &mut velocity,
+            knockback_velocity: &mut knockback_velocity,
+            knockback_state: &mut knockback_state,
+            surface: &mut surface,
+            ecb: &mut ecb,
+            desired_ecb: &mut desired_ecb,
+            ledge_info: &mut ledge_info,
+            prev_ecb: &previous_ecb,
+            stage_collision: &stage_collision,
+            leave_ground_ecb_lock_duration: 10,
+            presentation_snap: &mut presentation_snap,
+            downward_stick_threshold: FGi32::ONE,
+            fighter_ledge_collision_box: FGRect {
+                origin: FGVec2::ZERO,
+                end: FGVec2::ZERO,
+            },
+            waveland_snap_distance: FGi32::ZERO,
+        };
+
+        assert!(matches!(
+            collide_with_stage_grounded(&mut context, true),
+            GroundedMotionResult::InAir
+        ));
+        assert!(matches!(surface, FighterSurfaceState::Airborne { .. }));
+    }
 }
 
 pub fn grounded_movement_common_interrupts(
     state_context: &InterruptContext,
-    ground_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
-    super::jump::check_input(state_context, ground_common)
+    super::jump::check_input(state_context)
 }
 
 pub fn grounded_movement_standstill_common_interrupts(
     state_context: &InterruptContext,
-    ground_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
-    if let Some(state) = ground_attack::check_interrupt(state_context, &ground_common) {
+    if let Some(state) = ground_attack::check_interrupt(state_context) {
         Some(state)
-    } else if let Some(state) = dash::check_input(state_context, &ground_common) {
+    } else if let Some(state) = dash::check_input(state_context) {
         Some(state)
-    } else if let Some(state) = turn::check_input(state_context, &ground_common) {
+    } else if let Some(state) = turn::check_input(state_context) {
         Some(state)
-    } else if let Some(state) = walk::check_input(state_context, &ground_common) {
+    } else if let Some(state) = crouch::check_input(state_context) {
         Some(state)
-    } else if let Some(state) = wait::check_input(state_context, &ground_common) {
+    } else if let Some(state) = walk::check_input(state_context) {
+        Some(state)
+    } else if let Some(state) = wait::check_input(state_context) {
         Some(state)
     } else {
         None
     }
 }
+
+pub fn perform_wavedash(input: &FighterInput, game_settings: &GameSettings) -> FighterState {
+    // If aiming sideways and in the deadzone, do a perfect wavedash
+    // TODO: Improve this so we don't have to go through the airborne state first
+    let mut wavedash_dir = input.get_last_frame().movement.normalize_or_zero();
+    let movement = input.get_last_frame().movement;
+    if movement.y.is_zero() && !movement.x.is_zero() {
+        wavedash_dir.y = -game_settings.input_common.stick_deadzone - FGi32::lit("-0.01");
+        wavedash_dir.x = movement.x.signum();
+    }
+
+    if wavedash_dir == FGVec2::ZERO {
+        wavedash_dir = FGVec2::lit("0.0", "-1.0");
+    }
+
+    FighterState::AirDodge(AirDodgeState {
+        direction: wavedash_dir.normalize_or_zero(),
+    })
+}

src/fighter/state/ground_attack.rs

@@ -1,25 +1,41 @@
-use crate::fighter::{
+use bevy::{asset::Assets, log::error};
-    attack::{AttackKind, update_active_hitbox_list},
+
-    state::{
+use crate::{
-        CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl,
+    fighter::{
-        InterruptContext, UpdateContext, ground::GroundedStateCommon, wait::WaitState,
+        attack::{AttackKind, FighterAttackScriptAssets, update_active_attack},
+        state::{
+            CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl,
+            InterruptContext, UpdateContext, ground, wait::WaitState,
+        },
     },
+    scripting::FighterAttackScript,
 };
 
 #[derive(Clone, Debug, Hash)]
 pub struct GroundAttackState {
     pub attack_kind: AttackKind,
-    pub grounded_common: GroundedStateCommon,
+    pub use_root_motion: bool,
 }
 
 impl FighterStateImpl for GroundAttackState {
     const NAME: &'static str = "GroundAttack";
 
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        // Allow interrupting dash attack only into an up/down smash
+        if let AttackKind::DashAttack = self.attack_kind {
+            if state_context.get_current_animation_frame() < state_context.fighter_attributes.dash_attack_cancel_window {
+                if let Some(state) = check_interrupt(state_context) {
+                    if let FighterState::GroundAttack(state) = state {
+                        if matches!(state.attack_kind, AttackKind::UpSmash) || matches!(state.attack_kind, AttackKind::DownSmash) {
+                            return Some(FighterState::GroundAttack(state));
+                        }
+                    }
+                }
+            }
+        }
+
         if state_context.is_current_animation_finished() {
-            Some(FighterState::Wait(WaitState {
+            Some(FighterState::Wait(WaitState))
-                grounded_common: self.grounded_common.clone(),
-            }))
         } else {
             None
         }
@@ -31,29 +47,42 @@ impl FighterStateImpl for GroundAttackState {
             .attack_scripts
             .get(&state_context.attack_script_assets.scripts[&self.attack_kind]);
         if let Some(script) = script {
-            update_active_hitbox_list(
+            update_active_attack(
                 script,
-                &mut state_context
+                state_context
                     .hitboxes
                     .0
                     .as_mut()
-                    .expect("ground attack must have active hitboxes")
+                    .expect("ground attack must have active hitboxes"),
-                    .active_hitboxes,
                 animation_frame,
             );
+
+            // root motion
+            if script.use_root_motion {
+                state_context.velocity.0.x = state_context.animation_root_motion_delta.x;
+                ground::apply_grounded_motion(
+                    state_context.velocity,
+                    state_context.translation,
+                );
+            } else {
+                ground::update_friction_motion(state_context);
+            }
         }
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context
+            .input
+            .consume_command(crate::input::FighterCommands::Attack);
         state_context.play_animation(self.attack_kind.get_animation(), false);
         let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
         state_context.hitboxes.0 = Some(crate::fighter::FighterActiveAttack {
             kind: self.attack_kind,
-            script,
+            script: script.clone(),
             active_hitboxes: Vec::new(),
             solved_hitboxes: Vec::new(),
-            hit_fighters: Vec::new(),
+            hit_groups: Vec::new(),
-            stalled: false
+            stalled: false,
         });
     }
 
@@ -63,22 +92,62 @@ impl FighterStateImpl for GroundAttackState {
 
     fn check_collision_interrupt(
         &mut self,
-        _state_context: &mut CollisionContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        None
+        ground::collision_interrupt(state_context, !self.use_root_motion)
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }
 
-pub fn check_interrupt(
+impl GroundAttackState {
-    state_context: &InterruptContext,
+    fn create(
-    grounded_common: &GroundedStateCommon,
+        attack_kind: AttackKind,
-) -> Option<FighterState> {
+        attack_script_assets: &FighterAttackScriptAssets,
+        attack_scripts: &Assets<FighterAttackScript>,
+    ) -> Result<Self, AirAttackStateCreateError> {
+        let asset_script = attack_script_assets.scripts.get(&attack_kind).ok_or(
+            AirAttackStateCreateError::AttackScriptAssetNotFound {
+                attack: attack_kind,
+            },
+        )?;
+
+        let script = attack_scripts.get(asset_script).ok_or(
+            AirAttackStateCreateError::AttackScriptNotFound {
+                attack: attack_kind,
+            },
+        )?;
+
+        Ok(Self {
+            attack_kind,
+            use_root_motion: script.use_root_motion
+        })
+    }
+}
+
+#[derive(thiserror::Error, Debug)]
+pub enum AirAttackStateCreateError {
+    #[error("Attack script: {attack:?} not found")]
+    AttackScriptNotFound { attack: AttackKind },
+    #[error("Attack script asset: {attack:?} not found")]
+    AttackScriptAssetNotFound { attack: AttackKind },
+}
+
+pub fn check_interrupt_shared(state_context: &InterruptContext, attack_kind: AttackKind) -> Option<FighterState> {
+    let state = GroundAttackState::create(attack_kind, state_context.attack_script_assets, state_context.attack_scripts);
+
+    match state {
+        Ok(state) => Some(FighterState::GroundAttack(state)),
+        Err(create_error) => {
+            error!("{}", create_error);
+            None
+        },
+    }
+}
+
+pub fn check_interrupt(state_context: &InterruptContext) -> Option<FighterState> {
     if state_context
         .input
         .has_command(crate::input::FighterCommands::Attack)
@@ -87,10 +156,18 @@ pub fn check_interrupt(
             .input
             .get_attack_command_type()
             .to_attack_kind_grounded();
-        Some(FighterState::GroundAttack(GroundAttackState {
+        check_interrupt_shared(state_context, attack_kind)
-            attack_kind,
+    } else {
-            grounded_common: grounded_common.clone(),
+        None
-        }))
+    }
+}
+
+pub fn check_interrupt_dash_attack(state_context: &InterruptContext) -> Option<FighterState> {
+    if state_context
+        .input
+        .has_command(crate::input::FighterCommands::Attack)
+    {
+        check_interrupt_shared(state_context, AttackKind::DashAttack)
     } else {
         None
     }

src/fighter/state/hitstun.rs

@@ -1,23 +1,20 @@
 use crate::{
     fighter::{
-        animation::AnimKind,
+        animation::AnimKind, attack::{self, FighterHitReaction}, state::{
-        attack::{self, FighterHitReaction},
-        state::{
             CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl,
             InterruptContext, UpdateContext,
             air::{self, AirborneStateCommon},
             fall::FallState,
-            ground::{GroundedStateCommon, collision_interrupt},
+            ground::collision_interrupt,
             land::LandingType,
             wait::WaitState,
         },
-    },
+    }, math::vec::FGVec2,
-    math::int::FGi32,
 };
 
 #[derive(Clone, Debug, Hash)]
 pub enum HitstopStateKind {
-    Grounded(GroundedStateCommon),
+    Grounded,
     Airborne,
 }
 
@@ -26,14 +23,20 @@ pub struct HitstunState {
     pub hit_reaction: FighterHitReaction,
     pub hitstop_kind: HitstopStateKind,
     knockback_applied: bool,
+    stack_previous_knockback: bool,
 }
 
 impl HitstunState {
-    pub fn new(hit_reaction: FighterHitReaction, hitstop_kind: HitstopStateKind) -> Self {
+    pub fn new(
+        hit_reaction: FighterHitReaction,
+        hitstop_kind: HitstopStateKind,
+        stack_previous_knockback: bool,
+    ) -> Self {
         Self {
             hit_reaction,
             hitstop_kind,
             knockback_applied: false,
+            stack_previous_knockback,
         }
     }
 }
@@ -41,9 +44,38 @@ impl HitstunState {
 impl FighterStateImpl for HitstunState {
     const NAME: &'static str = "Hitstun";
 
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        if state_context.get_current_animation_frame() > self.hit_reaction.hitstun_frames {
+            match &self.hitstop_kind {
+                HitstopStateKind::Grounded => Some(FighterState::Wait(WaitState)),
+                HitstopStateKind::Airborne => Some(FighterState::Fall(FallState::new(
+                    AirborneStateCommon::default(),
+                ))),
+            }
+        } else {
+            None
+        }
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        let animation = match self.hitstop_kind {
+            HitstopStateKind::Grounded => AnimKind::FlinchGround,
+            HitstopStateKind::Airborne => AnimKind::FlinchAir,
+        };
+        state_context.play_animation(animation, false);
+        state_context.velocity.0 = FGVec2::ZERO;
+    }
+
+    fn on_exit(&mut self, state_context: &mut ExitContext) {
+        if matches!(self.hitstop_kind, HitstopStateKind::Grounded) {
+            state_context.knockback_velocity.0 = FGVec2::ZERO;
+            state_context.knockback_state.clear();
+        }
+    }
+
     fn name(&self) -> String {
         let hitstop_kind = match self.hitstop_kind {
-            HitstopStateKind::Grounded(_) => "Grounded",
+            HitstopStateKind::Grounded => "Grounded",
             HitstopStateKind::Airborne => "Airborne",
         };
 
@@ -55,80 +87,74 @@ impl FighterStateImpl for HitstunState {
         format!("Hitstun ({hitstop_kind}, {hit_reaction_type})")
     }
 
-    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
-        if state_context.get_current_animation_frame() > self.hit_reaction.hitstun_frames {
-            match &self.hitstop_kind {
-                HitstopStateKind::Grounded(grounded_state_common) => {
-                    Some(FighterState::Wait(WaitState {
-                        grounded_common: grounded_state_common.clone(),
-                    }))
-                }
-                HitstopStateKind::Airborne => {
-                    Some(FighterState::Fall(FallState::new(AirborneStateCommon::default())))
-                }
-            }
-        } else {
-            None
-        }
-    }
-
     fn update(&mut self, ctx: &mut UpdateContext) {
         if !self.knockback_applied {
-            let launch_direction = attack::directional_influence::apply_directional_influence(
+            let new_launch_direction = attack::directional_influence::apply_directional_influence(
-                ctx.input.get_last_frame().movement,
+                FGVec2::ZERO,
                 self.hit_reaction.launch_angle,
                 ctx.game_settings.fighter_common.di_max_angle,
             );
+            let new_knockback = new_launch_direction * self.hit_reaction.launch_velocity;
+            let combined_knockback = if self.stack_previous_knockback {
+                attack::stack_knockback(ctx.knockback_velocity.0, new_knockback)
+            } else {
+                new_knockback
+            };
+            let launch_speed = combined_knockback.length();
+            let launch_direction =
+                attack::directional_influence::apply_directional_influence_to_direction(
+                    ctx.input.get_last_frame().movement,
+                    combined_knockback.normalize_or_zero(),
+                    ctx.game_settings.fighter_common.di_max_angle,
+                );
 
-            ctx.knockback_velocity.0 = launch_direction * self.hit_reaction.launch_velocity;
+            ctx.knockback_velocity.0 = launch_direction * launch_speed;
+            ctx.knockback_state.restart();
             self.knockback_applied = true;
         }
 
         match self.hitstop_kind {
-            HitstopStateKind::Grounded(_) => {}
+            HitstopStateKind::Grounded => {}
             HitstopStateKind::Airborne => {
                 air::integrate_gravity(ctx.velocity, ctx.fighter_attributes, false);
+                air::apply_air_motion_with_knockback(ctx);
             }
         }
 
-        let speed = ctx.knockback_velocity.length();
+        if matches!(self.hitstop_kind, HitstopStateKind::Grounded) {
-        let next_speed = speed
+            attack::decay_knockback(
-            .saturating_sub(ctx.game_settings.fighter_common.knockback_decay_per_frame)
+                ctx.knockback_velocity,
-            .max(FGi32::ZERO);
+                ctx.knockback_state,
-
+                ctx.game_settings.fighter_common.knockback_decay_per_frame,
-        ctx.knockback_velocity.0 = ctx.knockback_velocity.normalize_or_zero() * next_speed;
+            );
-
+        }
-        ctx.translation.0 += ctx.velocity.0 + ctx.knockback_velocity.0;
     }
 
-    fn on_enter(&mut self, state_context: &mut EnterContext) {
-        let animation = match self.hitstop_kind {
-            HitstopStateKind::Grounded(_) => AnimKind::FlinchGround,
-            HitstopStateKind::Airborne => AnimKind::FlinchAir,
-        };
-        state_context.play_animation(animation, false);
-    }
-
-    fn on_exit(&mut self, _state_context: &mut ExitContext) {}
-
     fn check_collision_interrupt(
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
         match &mut self.hitstop_kind {
-            HitstopStateKind::Grounded(grounded_state_common) => {
+            HitstopStateKind::Grounded => collision_interrupt(state_context, true),
-                collision_interrupt(state_context, grounded_state_common, true)
-            }
             HitstopStateKind::Airborne => {
-                air::collision_interrupt(state_context, LandingType::Normal)
+                air::collision_interrupt(state_context, LandingType::Normal, Default::default())
             }
         }
     }
 
     fn is_visually_grounded<'a>(&'a self) -> bool {
         match self.hitstop_kind {
-            HitstopStateKind::Grounded(_) => true,
+            HitstopStateKind::Grounded => true,
             HitstopStateKind::Airborne => false,
         }
     }
+
+    fn surface_policy(&self) -> super::SurfacePolicy {
+        match self.hitstop_kind {
+            HitstopStateKind::Grounded => super::SurfacePolicy::Grounded,
+            HitstopStateKind::Airborne => super::SurfacePolicy::Airborne(
+                crate::fighter::surface::EcbLockPolicy::StartOnDetach,
+            ),
+        }
+    }
 }

src/fighter/state/jump.rs

@@ -1,11 +1,10 @@
-use bevy::prelude::*;
 
 use crate::{
     fighter::{
         animation::AnimKind, state::{
-            CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext, UpdateContext, air::{self, AirborneStateCommon}, air_dodge::{self, AirDodgeState}, ground::{self, GroundedStateCommon},
+            CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext, UpdateContext, air::{self, AirborneStateCommon}, ground::{self}, ground_attack,
         },
-    }, input::FighterCommands, math::{int::FGi32, vec::FGVec2},
+    }, input::{DigitalAction, FighterCommands},
 };
 #[derive(Debug, Hash, Clone, Copy)]
 pub enum JumpType {
@@ -14,23 +13,30 @@ pub enum JumpType {
     DoubleJump,
 }
 
+#[derive(Debug, Clone, Hash)]
+pub enum JumpStateInitiator {
+    Tap,
+    Button,
+}
+
 #[derive(Debug, Clone, Hash)]
 pub struct JumpState {
-    jump_type: JumpType,
+    pub jump_type: JumpType,
-    airborne_state_common: AirborneStateCommon,
+    pub airborne_state_common: AirborneStateCommon,
+    pub initiator: JumpStateInitiator,
 }
 
 #[derive(Debug, Clone, Hash)]
 pub struct JumpSquatState {
-    pub grounded_common: GroundedStateCommon,
     pub duration_counter: u32,
+    pub initiator: JumpStateInitiator,
 }
 
 impl JumpSquatState {
-    pub fn create(grounded_common: GroundedStateCommon) -> Self {
+    pub fn create(initiator: JumpStateInitiator) -> Self {
         Self {
-            grounded_common,
             duration_counter: 0,
+            initiator,
         }
     }
 }
@@ -39,37 +45,34 @@ impl FighterStateImpl for JumpSquatState {
     const NAME: &'static str = "JumpSquat";
 
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        if let Some(state) = ground_attack::check_interrupt(state_context) {
+            return Some(state);
+        }
         // Special handling for wavedash from jump squat
         if state_context.input.has_command(FighterCommands::Shield) {
-            // If aiming sideways and in the deadzone, do a perfect wavedash
+            Some(ground::perform_wavedash(state_context.input, state_context.game_settings))
-            // TODO: Improve this so we don't have to go through the airborne state first
-            let mut wavedash_dir = state_context
-                .input
-                .get_last_frame()
-                .movement
-                .normalize_or_zero();
-            let movement = state_context.input.get_last_frame().movement;
-            if movement.y.is_zero() && !movement.x.is_zero() {
-                wavedash_dir.y =
-                    -state_context.game_settings.input_common.stick_deadzone - FGi32::lit("-0.01");
-                wavedash_dir.x = movement.x.signum();
-            }
-
-            if wavedash_dir == FGVec2::ZERO {
-                wavedash_dir = FGVec2::lit("0.0", "-1.0");
-            }
-
-            Some(FighterState::AirDodge(AirDodgeState {
-                direction: wavedash_dir.normalize_or_zero(),
-            }))
         } else if self.duration_counter >= state_context.fighter_attributes.jumpsquat_duration {
-            info!("Jump {}", state_context.input.get_last_frame().jump);
+            let tap_jump_held = matches!(self.initiator, JumpStateInitiator::Tap)
-            let jump_type = if state_context.input.get_last_frame().jump {
+                && state_context.input.get_last_frame().movement.y
+                    > state_context
+                        .game_settings
+                        .input_common
+                        .smash_input_axis_threshold;
+            let jump_type = if tap_jump_held
+                || state_context
+                    .input
+                    .get_last_frame()
+                    .is_held(DigitalAction::Jump)
+            {
                 JumpType::LongJump
             } else {
                 JumpType::ShortHop
             };
-            Some(FighterState::Jump(JumpState { jump_type, airborne_state_common: AirborneStateCommon::default() }))
+            Some(FighterState::Jump(JumpState {
+                jump_type,
+                airborne_state_common: AirborneStateCommon::default(),
+                initiator: self.initiator.clone(),
+            }))
         } else {
             None
         }
@@ -84,17 +87,23 @@ impl FighterStateImpl for JumpSquatState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
+        ground::collision_interrupt(state_context, false)
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::JumpSquat, false);
+        state_context.input.enable_hold_all(10);
         state_context.input.clear_command(FighterCommands::Jump);
+        state_context.input.clear_command(FighterCommands::TapJump);
     }
 
-    fn is_visually_grounded<'a>(
+    fn on_exit(&mut self, state_context: &mut crate::fighter::state::ExitContext) {
-        &'a self,
+        state_context.input.disable_hold_all();
-    ) -> bool {
+        // We clear tap jump here, it may have weird interactions with air dodging up
+        state_context.input.clear_command(FighterCommands::TapJump);
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
         true
     }
 }
@@ -102,14 +111,7 @@ impl FighterStateImpl for JumpSquatState {
 impl FighterStateImpl for JumpState {
     const NAME: &'static str = "Jump";
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
-        if state_context.input.has_command(FighterCommands::Jump) {
+        air::air_interrupts_common(state_context, &self.airborne_state_common)
-            Some(FighterState::Jump(JumpState {
-                jump_type: JumpType::DoubleJump,
-                airborne_state_common: AirborneStateCommon::default()
-            }))
-        } else {
-            air_dodge::check_input(state_context)
-        }
     }
 
     fn update(&mut self, state_context: &mut UpdateContext) {
@@ -174,34 +176,56 @@ impl FighterStateImpl for JumpState {
         air::collision_interrupt(
             state_context,
             crate::fighter::state::land::LandingType::Normal,
+            crate::fighter::collision::AirCollisionOptions {
+                can_pass_through_soft_platforms: true,
+                ..Default::default()
+            },
         )
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         false
     }
+
+    fn surface_policy(&self) -> super::SurfacePolicy {
+        use crate::fighter::surface::EcbLockPolicy;
+        match self.jump_type {
+            JumpType::DoubleJump => super::SurfacePolicy::Airborne(EcbLockPolicy::Restart),
+            JumpType::ShortHop | JumpType::LongJump => {
+                super::SurfacePolicy::Airborne(EcbLockPolicy::StartOnDetach)
+            }
+        }
+    }
 }
 
-pub fn check_input(
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context: &InterruptContext,
+    if state_context.input.has_command(FighterCommands::Jump) {
-    ground_common: &GroundedStateCommon,
+        Some(FighterState::JumpSquat(JumpSquatState::create(
-) -> Option<FighterState> {
+            JumpStateInitiator::Button,
-    state_context
+        )))
-        .input
+    } else if state_context.input.has_command(FighterCommands::TapJump) {
-        .has_command(FighterCommands::Jump)
+        Some(FighterState::JumpSquat(JumpSquatState::create(
-        .then(|| FighterState::JumpSquat(JumpSquatState::create(ground_common.clone())))
+            JumpStateInitiator::Tap,
+        )))
+    } else {
+        None
+    }
 }
 
 pub fn check_input_double_jump(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context
+    if state_context.input.has_command(FighterCommands::Jump) {
-        .input
+        Some(FighterState::Jump(JumpState {
-        .has_command(FighterCommands::Jump)
+            jump_type: JumpType::DoubleJump,
-        .then(|| {
+            airborne_state_common: AirborneStateCommon::default(),
-            FighterState::Jump(JumpState {
+            initiator: JumpStateInitiator::Button,
-                jump_type: JumpType::DoubleJump,
+        }))
-                airborne_state_common: AirborneStateCommon::default()
+    } else if state_context.input.has_command(FighterCommands::TapJump) {
-            })
+        Some(FighterState::Jump(JumpState {
-        })
+            jump_type: JumpType::DoubleJump,
+            airborne_state_common: AirborneStateCommon::default(),
+            initiator: JumpStateInitiator::Tap,
+        }))
+    } else {
+        None
+    }
 }

src/fighter/state/land.rs

@@ -3,7 +3,7 @@ use crate::fighter::{
     state::{
         CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext,
         UpdateContext, dash,
-        ground::{self, GroundedStateCommon, grounded_movement_standstill_common_interrupts},
+        ground::{self, grounded_movement_standstill_common_interrupts},
         walk,
     },
 };
@@ -16,16 +16,12 @@ pub enum LandingType {
 
 #[derive(Debug, Clone, Hash)]
 pub struct LandingState {
-    pub grounded_common: GroundedStateCommon,
     pub landing_type: LandingType,
 }
 
 impl LandingState {
-    pub fn create(grounded_common: GroundedStateCommon, landing_type: LandingType) -> Self {
+    pub fn create(landing_type: LandingType) -> Self {
-        Self {
+        Self { landing_type }
-            grounded_common,
-            landing_type,
-        }
     }
 }
 
@@ -34,14 +30,14 @@ impl FighterStateImpl for LandingState {
 
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if state_context.is_current_animation_finished() {
-            grounded_movement_standstill_common_interrupts(state_context, &self.grounded_common)
+            grounded_movement_standstill_common_interrupts(state_context)
         } else if state_context.get_current_animation_frame()
             >= state_context.fighter_attributes.landing_iasa
             && let LandingType::Normal = self.landing_type
         {
-            dash::check_input(state_context, &self.grounded_common).or_else(|| {
+            dash::check_input(state_context).or_else(|| {
-                ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
+                ground::grounded_movement_common_interrupts(state_context)
-                    .or_else(|| walk::check_input(state_context, &self.grounded_common))
+                    .or_else(|| walk::check_input(state_context))
             })
         } else {
             None
@@ -56,7 +52,7 @@ impl FighterStateImpl for LandingState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.grounded_common, true)
+        ground::collision_interrupt(state_context, true)
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
@@ -70,9 +66,7 @@ impl FighterStateImpl for LandingState {
         };
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }

src/fighter/state/ledge_action.rs

@@ -0,0 +1,157 @@
+use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
+use crate::fighter::animation::AnimKind;
+use crate::fighter::state::air::AirborneStateCommon;
+use crate::fighter::state::jump::{JumpState, JumpStateInitiator, JumpType};
+use crate::fighter::state::wait::WaitState;
+use crate::fighter::state::{FighterState, ground};
+use crate::fighter::FighterFacingDirection;
+use crate::input::FighterCommands;
+use crate::math::int::FGi32;
+use crate::math::vec::FGVec2;
+use crate::stage::line::{StageLedgeSide, StageVertexID};
+
+#[derive(Debug, Clone, Hash)]
+pub enum LedgeAction {
+    Jump(JumpStateInitiator),
+    GetUp
+}
+
+#[derive(Debug, Clone, Hash)]
+pub struct LedgeActionState {
+    pub ledge_id: StageVertexID,
+    pub ledge_action: LedgeAction,
+    pub is_in_grounded_phase: bool,
+}
+
+impl LedgeActionState {
+    pub fn create_jump(ledge_id: StageVertexID, initiator: JumpStateInitiator) -> Self {
+        LedgeActionState {
+            ledge_id,
+            ledge_action: LedgeAction::Jump(initiator),
+            is_in_grounded_phase: false,
+        }
+    }
+    pub fn create_getup(ledge_id: StageVertexID) -> Self {
+        LedgeActionState {
+            ledge_id,
+            ledge_action: LedgeAction::GetUp,
+            is_in_grounded_phase: false,
+        }
+    }
+}
+
+impl FighterStateImpl for LedgeActionState {
+    const NAME: &'static str = "LedgeAction";
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        match &self.ledge_action {
+            LedgeAction::Jump(initiator) => {
+                if state_context.is_current_animation_finished() {
+                    if state_context.input.has_command(FighterCommands::Shield) {
+                        Some(ground::perform_wavedash(state_context.input, state_context.game_settings))
+                    } else {
+                        Some(FighterState::Jump(JumpState {
+                            jump_type: JumpType::DoubleJump,
+                            airborne_state_common: AirborneStateCommon::default(),
+                            initiator: initiator.clone()
+                        }))
+                    }
+                } else {
+                    None
+                }
+            },
+            LedgeAction::GetUp => {
+                if state_context.is_current_animation_finished() {
+                    Some(FighterState::Wait(WaitState))
+                } else {
+                    None
+                }
+            },
+        }
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        match self.ledge_action {
+            LedgeAction::Jump(_) => {
+                state_context.play_animation(AnimKind::LedgeJump, false);
+                state_context.input.enable_hold_all(10);
+                state_context.input.clear_command(FighterCommands::Jump);
+                state_context.input.clear_command(FighterCommands::TapJump);
+            },
+            LedgeAction::GetUp => {
+                state_context.play_animation(AnimKind::LedgeGetUp, false);
+            },
+        }
+
+        state_context.velocity.0 = FGVec2::ZERO;
+        state_context.knockback_velocity.0 = FGVec2::ZERO;
+        state_context.knockback_state.clear();
+        let Some(ledge) = state_context.stage_collision.find_ledge_by_vertex(self.ledge_id) else {
+            return;
+        };
+        state_context.translation.0 = ledge.position;
+        *state_context.facing_direction = match ledge.hang_side {
+            StageLedgeSide::Left => FighterFacingDirection::Right,
+            StageLedgeSide::Right => FighterFacingDirection::Left,
+        };
+        if let Some(root_position) = state_context.initial_animation_root_position() {
+            state_context.translation.0 = root_position;
+        }
+        state_context.presentation_snap.0 = true;
+    }
+
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        if !self.is_in_grounded_phase {
+            let root_pos = state_context.animation_root_position.unwrap_or_default();
+            let Some(ledge) = state_context.stage_collision.find_ledge_by_vertex(self.ledge_id) else {
+                return;
+            };
+
+            let ledge_pos = ledge.position;
+            let ledge_modifier = match ledge.hang_side {
+                StageLedgeSide::Left => FGi32::ONE,
+                StageLedgeSide::Right => FGi32::NEG_ONE,
+            };
+
+            let normalized_root_position = root_pos - ledge_pos;
+            let normalized_root_position = FGVec2::new(normalized_root_position.x * ledge_modifier, normalized_root_position.y);
+            
+            if normalized_root_position.x.is_positive() && normalized_root_position.y.is_positive() {
+                let Some((segment_id, _)) = state_context
+                    .stage_collision
+                    .find_ledge_ground_segment(self.ledge_id)
+                else {
+                    return;
+                };
+
+                self.is_in_grounded_phase = true;
+                state_context.translation.0 = ledge.position;
+                state_context.surface.land(segment_id, state_context.ledge_info);
+            }
+        }
+
+        if self.is_in_grounded_phase {
+            state_context.velocity.0.x = state_context.animation_root_motion_delta.x;
+            ground::apply_grounded_motion(
+                state_context.velocity,
+                state_context.translation,
+            );
+        } else {
+            if let Some(root_position) = state_context.animation_root_position {
+                state_context.translation.0 = root_position;
+            }
+        }
+
+    }
+
+    fn check_collision_interrupt(
+        &mut self,
+        state_context: &mut CollisionContext,
+    ) -> Option<FighterState> {
+        state_context.apply_desired_ecb();
+        None
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
+        self.is_in_grounded_phase
+    }
+}

src/fighter/state/ledge_grab.rs

@@ -0,0 +1,75 @@
+use super::{
+    EnterContext, FighterStateImpl, InterruptContext, UpdateContext,
+};
+use crate::fighter::{FighterFacingDirection, FighterInvulnerabilityState};
+use crate::fighter::animation::AnimKind;
+use crate::fighter::state::{ExitContext, FighterState};
+use crate::fighter::state::air::AirborneStateCommon;
+use crate::fighter::state::ledge_wait::LedgeWaitState;
+use crate::stage::line::{StageLedgeSide, StageVertexID};
+
+#[derive(Debug, Clone, Hash)]
+pub struct LedgeGrabState {
+    ledge_id: StageVertexID
+}
+
+impl LedgeGrabState {
+    pub fn new(ledge_id: StageVertexID) -> Self {
+        Self {
+            ledge_id
+        }
+    }
+}
+
+impl FighterStateImpl for LedgeGrabState {
+    const NAME: &'static str = "LedgeGrab";
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        if state_context.is_current_animation_finished() {
+            Some(FighterState::LedgeWait(LedgeWaitState {
+                airborne_state_common: AirborneStateCommon::default(),
+                ledge_id: self.ledge_id.clone()
+            }))
+        } else {
+            None
+        }
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context.play_animation(AnimKind::LedgeGrab, false);
+        state_context.knockback_velocity.0 = crate::math::vec::FGVec2::ZERO;
+        state_context.knockback_state.clear();
+
+        *state_context.vulnerability = FighterInvulnerabilityState::Intangible {
+            frames_remaining: None,
+        };
+
+        let Some(ledge) = state_context.stage_collision.find_ledge_by_vertex(self.ledge_id) else {
+            return;
+        };
+        state_context.translation.0 = ledge.position;
+        *state_context.facing_direction = match ledge.hang_side {
+            StageLedgeSide::Left => FighterFacingDirection::Right,
+            StageLedgeSide::Right => FighterFacingDirection::Left,
+        };
+        if let Some(root_position) = state_context.initial_animation_root_position() {
+            state_context.translation.0 = root_position;
+        }
+        state_context.presentation_snap.0 = true;
+
+
+    }
+
+    fn on_exit(&mut self, state_context: &mut ExitContext) {
+        *state_context.vulnerability = FighterInvulnerabilityState::Vulnerable;
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
+        false
+    }
+    
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        if let Some(root_position) = state_context.animation_root_position {
+            state_context.translation.0 = root_position;
+        }
+    }
+}

src/fighter/state/ledge_wait.rs

@@ -0,0 +1,167 @@
+use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
+use crate::fighter::animation::AnimKind;
+use crate::fighter::state::air::AirborneStateCommon;
+use crate::fighter::state::fall::FallState;
+use crate::fighter::state::FighterState;
+use crate::fighter::state::jump::JumpStateInitiator;
+use crate::fighter::state::ledge_action::{LedgeActionState};
+use crate::fighter::{FighterFacingDirection, FighterInvulnerabilityState};
+use crate::input::FighterCommands;
+use crate::math::vec::FGVec2;
+use crate::stage::line::{StageLedgeSide, StageVertexID};
+
+#[derive(Debug, Clone, Hash)]
+pub struct LedgeWaitState {
+    pub airborne_state_common: AirborneStateCommon,
+    pub ledge_id: StageVertexID,
+}
+
+impl FighterStateImpl for LedgeWaitState {
+    const NAME: &'static str = "LedgeWait";
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        if state_context.input.has_command(FighterCommands::Jump) {
+            return Some(FighterState::LedgeAction(LedgeActionState::create_jump(self.ledge_id, JumpStateInitiator::Button)));
+        } else if state_context.input.has_command(FighterCommands::TapJump) {
+            return Some(FighterState::LedgeAction(LedgeActionState::create_jump(self.ledge_id, JumpStateInitiator::Tap)));
+        }
+
+        if is_ledge_getup_input(state_context.input.get_last_frame().movement.x,
+            state_context.game_settings.input_common.run_stick_threshold,
+            state_context.facing_direction) {
+                return Some(FighterState::LedgeAction(LedgeActionState::create_getup(self.ledge_id)));
+        }
+
+        if is_ledge_drop_input(state_context.input.get_last_frame().movement.x,
+            state_context.game_settings.input_common.run_stick_threshold,
+            state_context.facing_direction) {
+            state_context.ledge_grab_lockout.start(
+                state_context
+                    .game_settings
+                    .fighter_common
+                    .ledge_drop_regrab_lockout_duration_frames,
+            );
+            return Some(FighterState::Fall(FallState::new(
+                AirborneStateCommon { is_fast_falling: false },
+            )));
+        }
+        if is_ledge_drop_fastfall_input(
+            state_context.input.get_last_frame().movement.y,
+            state_context.game_settings.input_common.run_stick_threshold,
+        ) {
+            state_context.ledge_grab_lockout.start(
+                state_context
+                    .game_settings
+                    .fighter_common
+                    .ledge_drop_regrab_lockout_duration_frames,
+            );
+            return Some(FighterState::Fall(FallState::new(
+                AirborneStateCommon { is_fast_falling: true },
+            )));
+        }
+
+        None
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context.velocity.0 = FGVec2::ZERO;
+        state_context.knockback_velocity.0 = FGVec2::ZERO;
+        state_context.knockback_state.clear();
+        
+        if state_context.ledge_info.grab_count < state_context.game_settings.fighter_common.max_ledge_grab_count {
+            *state_context.vulnerability = FighterInvulnerabilityState::Intangible {
+                frames_remaining: Some(
+                    state_context
+                    .game_settings
+                    .fighter_common
+                    .ledge_grab_invulnerability_duration,
+                ),
+            };
+        }
+
+        state_context.ledge_info.grab_count = state_context.ledge_info.grab_count.saturating_add(1);
+        
+        let Some(ledge) = state_context.stage_collision.find_ledge_by_vertex(self.ledge_id) else {
+            return;
+        };
+        state_context.translation.0 = ledge.position;
+        *state_context.facing_direction = match ledge.hang_side {
+            StageLedgeSide::Left => FighterFacingDirection::Right,
+            StageLedgeSide::Right => FighterFacingDirection::Left,
+        };
+        state_context.play_animation(AnimKind::LedgeWait, true);
+        if let Some(root_position) = state_context.initial_animation_root_position() {
+            state_context.translation.0 = root_position;
+        }
+        state_context.presentation_snap.0 = true;
+    }
+
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        if let Some(root_position) = state_context.animation_root_position {
+            state_context.translation.0 = root_position;
+        }
+    }
+
+    fn check_collision_interrupt(
+        &mut self,
+        state_context: &mut CollisionContext,
+    ) -> Option<FighterState> {
+        state_context.apply_desired_ecb();
+        None
+    }
+
+    fn is_visually_grounded<'a>(&'a self) -> bool {
+        false
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::math::int::FGi32;
+
+    #[test]
+    fn ledge_drop_uses_the_run_stick_threshold() {
+        let threshold = FGi32::lit("0.625");
+
+        assert!(is_ledge_drop_fastfall_input(FGi32::lit("-0.625"), threshold));
+        assert!(is_ledge_drop_fastfall_input(FGi32::lit("-1.0"), threshold));
+        assert!(!is_ledge_drop_fastfall_input(FGi32::lit("-0.624"), threshold));
+    }
+}
+
+fn is_ledge_drop_fastfall_input(
+    vertical_input: crate::math::int::FGi32,
+    threshold: crate::math::int::FGi32,
+) -> bool {
+    vertical_input <= -threshold
+}
+
+fn is_ledge_drop_input(
+    horizontal_input: crate::math::int::FGi32,
+    threshold: crate::math::int::FGi32,
+    facing_dir: &FighterFacingDirection,
+) -> bool {
+    let dir = facing_dir.to_sign();
+    if horizontal_input.abs() > threshold {
+        if dir != horizontal_input.signum() {
+            return true;
+        }
+    }
+
+    false
+}
+
+fn is_ledge_getup_input(
+    horizontal_input: crate::math::int::FGi32,
+    threshold: crate::math::int::FGi32,
+    facing_dir: &FighterFacingDirection,
+) -> bool {
+    let dir = facing_dir.to_sign();
+    if horizontal_input.abs() > threshold {
+        if dir == horizontal_input.signum() {
+            return true;
+        }
+    }
+
+    false
+}

src/fighter/state/mod.rs

@@ -7,25 +7,41 @@ use bevy::prelude::*;
 
 use crate::fighter::animation::{AnimKind, FighterAnimationFrame};
 use crate::fighter::attack::{
-    FighterAttackScriptAssets, FighterKnockbackVelocity, FighterPendingHitReaction, FighterStaleMoveQueue, HitStop,
+    FighterAttackScriptAssets, FighterKnockbackState, FighterKnockbackVelocity,
+    FighterPendingHitReaction, FighterStaleMoveQueue, HitStop,
 };
 use crate::fighter::attributes::FighterAttributes;
-use crate::fighter::baked_animation::BakedFighterAnimations;
+use crate::fighter::baked_animation::{BakedFighterAnimations, FighterBoneMatrices};
-use crate::fighter::ecb::FighterPreviousECB;
+use crate::fighter::ecb::{self, FighterDesiredECB, FighterPreviousECB};
 use crate::fighter::manifest::FighterManifest;
 use crate::fighter::state::hitstun::HitstunState;
+use crate::fighter::surface::EcbLockPolicy;
 use crate::fighter::visual::FighterAnimations;
 use crate::fighter::{
-    Fighter, FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop, FighterHitstopShake, FighterHitstopShakeKind, FighterHitstopShakeRole, FighterPreviousTranslation, FighterTranslation, FighterVelocity,
+    Fighter, FighterDamage, FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop,
+    FighterHitstopShake, FighterHitstopShakeKind, FighterHitstopShakeRole,
+    FighterInvulnerabilityState, FighterLedgeInformation, FighterPendingRespawn,
+    FighterPresentationSnap, FighterPreviousTranslation, FighterSurfaceState, FighterTranslation,
+    FighterVelocity,
 };
 use crate::game_settings::GameSettings;
 use crate::input::FighterInput;
+use crate::match_loading::MatchConfig;
+use crate::match_runtime::MatchState;
 use crate::math::int::FGi32;
+use crate::math::rect::FGRect;
+use crate::math::vec::FGVec2;
+use crate::math::vec3::FGVec3;
+use crate::player::Player;
 use crate::scripting::FighterAttackScript;
 use crate::stage::line::StageCollision;
+use crate::stage::manifest::{StageManifest, StageManifestRegistry};
 
 pub mod air;
+pub mod air_attack;
 pub mod air_dodge;
+pub mod angel;
+pub mod crouch;
 pub mod dash;
 pub mod fall;
 pub mod ground;
@@ -33,11 +49,21 @@ pub mod ground_attack;
 pub mod hitstun;
 pub mod jump;
 pub mod land;
+pub mod ledge_action;
+pub mod ledge_grab;
+pub mod ledge_wait;
+pub mod platform_pass;
 pub mod run;
 pub mod turn;
 pub mod wait;
 pub mod walk;
 
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
+pub enum SurfacePolicy {
+    Grounded,
+    Airborne(EcbLockPolicy),
+}
+
 macro_rules! fighter_states {
     ($($variant:ident => $ty:ty),* $(,)?) => {
         #[derive(Component, Clone, Debug, Hash)]
@@ -69,6 +95,10 @@ macro_rules! fighter_states {
             pub fn is_visually_grounded(&self) -> bool {
                 match self { $(Self::$variant(s) => s.is_visually_grounded()),* }
             }
+
+            pub fn surface_policy(&self) -> SurfacePolicy {
+                match self { $(Self::$variant(s) => s.surface_policy()),* }
+            }
         }
 
         $(impl From<$ty> for FighterState {
@@ -90,14 +120,17 @@ pub trait FighterStateImpl: Sized {
 
     fn check_collision_interrupt(
         &mut self,
-        _state_context: &mut CollisionContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
+        state_context.apply_desired_ecb();
         None
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool;
-        &'a self,
+
-    ) -> bool;
+    fn surface_policy(&self) -> SurfacePolicy {
+        SurfacePolicy::Grounded
+    }
 }
 
 pub struct AnimationStatus {
@@ -108,9 +141,14 @@ pub struct AnimationStatus {
 pub struct InterruptContext<'a> {
     pub input: &'a FighterInput,
     pub facing_direction: &'a mut FighterFacingDirection,
+    pub ledge_grab_lockout: &'a mut FighterLedgeInformation,
     pub game_settings: &'a GameSettings,
     pub fighter_attributes: &'a FighterAttributes,
+    pub surface: &'a FighterSurfaceState,
     pub animation: AnimationStatus,
+    pub stage_collision: &'a StageCollision,
+    pub attack_scripts: &'a Assets<FighterAttackScript>,
+    pub attack_script_assets: &'a FighterAttackScriptAssets,
 }
 
 impl InterruptContext<'_> {
@@ -127,22 +165,50 @@ pub struct EnterContext<'a> {
     pub input: &'a mut FighterInput,
     pub hitboxes: &'a mut FighterHitboxes,
     pub velocity: &'a mut FighterVelocity,
+    pub translation: &'a mut FighterTranslation,
     pub knockback_velocity: &'a mut FighterKnockbackVelocity,
+    pub knockback_state: &'a mut FighterKnockbackState,
     pub stale_move_queue: &'a mut FighterStaleMoveQueue,
     pub facing_direction: &'a mut FighterFacingDirection,
     pub animation_frame: &'a mut FighterAnimationFrame,
+    pub presentation_snap: &'a mut FighterPresentationSnap,
+    pub surface: &'a mut FighterSurfaceState,
+    pub vulnerability: &'a mut FighterInvulnerabilityState,
+    pub ledge_info: &'a mut FighterLedgeInformation,
     pub fighter_attributes: &'a FighterAttributes,
     pub attack_script_assets: &'a FighterAttackScriptAssets,
+    pub game_settings: &'a GameSettings,
+    pub stage_collision: &'a StageCollision,
+    baked_animations: &'a BakedFighterAnimations,
+    model_scale: FGi32,
 }
 
 impl EnterContext<'_> {
     pub fn play_animation(&mut self, kind: AnimKind, repeat: bool) {
         self.animation_frame.reset(kind, repeat);
     }
+
+    /// World-space root position authored for frame zero of the animation most
+    /// recently selected with [`Self::play_animation`].
+    pub fn initial_animation_root_position(&self) -> Option<FGVec2> {
+        let position = self
+            .baked_animations
+            .initial_root_position(self.animation_frame.kind, self.model_scale)?;
+        Some(self.translation.0 + animation_position_to_gameplay(position, self.facing_direction))
+    }
+
+    pub fn get_animation_duration(&self, kind: AnimKind) -> Option<usize> {
+        self.baked_animations.get_animation_duration(kind)
+    }
 }
 
 pub struct ExitContext<'a> {
+    pub input: &'a mut FighterInput,
     pub hitboxes: &'a mut FighterHitboxes,
+    pub knockback_velocity: &'a mut FighterKnockbackVelocity,
+    pub knockback_state: &'a mut FighterKnockbackState,
+    pub surface: &'a mut FighterSurfaceState,
+    pub vulnerability: &'a mut FighterInvulnerabilityState,
 }
 
 pub struct UpdateContext<'a> {
@@ -151,13 +217,31 @@ pub struct UpdateContext<'a> {
     pub input: &'a mut FighterInput,
     pub hitboxes: &'a mut FighterHitboxes,
     pub velocity: &'a mut FighterVelocity,
+    pub surface: &'a mut FighterSurfaceState,
     pub knockback_velocity: &'a mut FighterKnockbackVelocity,
+    pub knockback_state: &'a mut FighterKnockbackState,
+    pub vulnerability: &'a mut FighterInvulnerabilityState,
+    pub ledge_info: &'a mut FighterLedgeInformation,
     pub game_settings: &'a GameSettings,
+    /// Root motion in the fighter's gameplay plane: X is world-right and Y is
+    /// world-up. Animation +Z is forward and is mirrored by facing direction.
+    pub animation_root_motion_delta: FGVec2,
+    /// Current world-space root position implied by this animation frame.
+    /// States opt into root motion by assigning this to [`FighterTranslation`].
+    pub animation_root_position: Option<FGVec2>,
     pub animation_frame: u32,
     pub fighter_attributes: &'a FighterAttributes,
     pub attack_scripts: &'a Assets<FighterAttackScript>,
     pub attack_script_assets: &'a FighterAttackScriptAssets,
     pub facing_direction: &'a FighterFacingDirection,
+    pub stage_collision: &'a StageCollision,
+}
+
+fn animation_position_to_gameplay(
+    position: FGVec3,
+    facing_direction: &FighterFacingDirection,
+) -> FGVec2 {
+    FGVec2::new(position.z * facing_direction.to_sign(), position.y)
 }
 
 impl UpdateContext<'_> {
@@ -169,21 +253,56 @@ impl UpdateContext<'_> {
 pub struct CollisionContext<'a> {
     pub translation: &'a mut FighterTranslation,
     pub prev_translation: &'a FighterPreviousTranslation,
+    pub input: &'a FighterInput,
     pub velocity: &'a mut FighterVelocity,
-    pub ecb: &'a FighterECB,
+    pub knockback_velocity: &'a mut FighterKnockbackVelocity,
+    pub knockback_state: &'a mut FighterKnockbackState,
+    pub surface: &'a mut FighterSurfaceState,
+    pub ecb: &'a mut FighterECB,
+    pub desired_ecb: &'a mut FighterDesiredECB,
     pub prev_ecb: &'a FighterPreviousECB,
     pub stage_collision: &'a StageCollision,
+    pub leave_ground_ecb_lock_duration: u32,
+    pub presentation_snap: &'a mut FighterPresentationSnap,
+    pub ledge_info: &'a mut FighterLedgeInformation,
+    pub fighter_ledge_collision_box: FGRect,
+    pub downward_stick_threshold: FGi32,
+    pub waveland_snap_distance: FGi32,
 }
 
 impl CollisionContext<'_> {
+    /// Commit the target pose before resolving this frame. The collision
+    /// substep resolver can later replace this with fractional steps.
+    pub fn apply_desired_ecb(&mut self) {
+        ecb::interpolate_ecb(self.ecb, *self.desired_ecb, FGi32::ONE);
+    }
+
     pub fn air_collide_with_stage(
-        &self,
+        &mut self,
+        mut options: crate::fighter::collision::AirCollisionOptions,
     ) -> Option<crate::fighter::collision::AirCollisionWithStageResult> {
-        crate::fighter::collision::air_collide_with_stage(
+        let ignored_polys = self.surface.ignored_polygon_ids();
+        options.can_pass_through_soft_platforms = options.can_pass_through_soft_platforms
+            && self.input.get_last_frame().movement.y <= -self.downward_stick_threshold;
+        crate::fighter::collision::air_collide_with_stage_substepped(
             self.prev_translation,
             self.translation,
-            self.prev_ecb,
+            self.velocity,
             self.ecb,
+            self.desired_ecb,
+            self.stage_collision,
+            &ignored_polys,
+            options,
+        )
+    }
+    pub fn air_collide_with_ledges(
+        &self,
+    ) -> Option<crate::fighter::collision::AirCollisionWithLedgeResult> {
+        if self.ledge_info.is_regrab_lockout_active() {
+            return None;
+        }
+        crate::fighter::collision::air_collide_with_ledges(
+            &self.fighter_ledge_collision_box,
             self.stage_collision,
         )
     }
@@ -192,16 +311,23 @@ impl CollisionContext<'_> {
 fighter_states! {
     Wait => wait::WaitState,
     Walk => walk::WalkState,
+    PlatformPass => platform_pass::PlatformPassState,
+    Crouch => crouch::CrouchState,
     Dash => dash::DashState,
     Run => run::RunState,
     Fall => fall::FallState,
     JumpSquat => jump::JumpSquatState,
     Jump => jump::JumpState,
     Land => land::LandingState,
+    LedgeWait => ledge_wait::LedgeWaitState,
+    LedgeAction => ledge_action::LedgeActionState,
+    LedgeGrab => ledge_grab::LedgeGrabState,
     AirDodge => air_dodge::AirDodgeState,
     Turn => turn::TurnState,
     GroundAttack => ground_attack::GroundAttackState,
     Hitstun => hitstun::HitstunState,
+    Angel => angel::AngelState,
+    AirAttack => air_attack::AirAttackState,
 }
 
 #[derive(QueryData)]
@@ -209,16 +335,23 @@ fighter_states! {
 pub struct FighterFrameQuery {
     pub translation: &'static mut FighterTranslation,
     pub prev_translation: &'static mut FighterPreviousTranslation,
+    pub presentation_snap: &'static mut FighterPresentationSnap,
     pub input: &'static mut FighterInput,
     pub hitboxes: &'static mut FighterHitboxes,
     pub velocity: &'static mut FighterVelocity,
+    pub surface: &'static mut FighterSurfaceState,
     pub knockback_velocity: &'static mut FighterKnockbackVelocity,
+    pub knockback_state: &'static mut FighterKnockbackState,
     pub stale_move_queue: &'static mut FighterStaleMoveQueue,
-    pub ecb: &'static FighterECB,
+    pub ecb: &'static mut FighterECB,
+    pub desired_ecb: &'static mut FighterDesiredECB,
     pub prev_ecb: &'static FighterPreviousECB,
     pub facing_direction: &'static mut FighterFacingDirection,
     pub animation_frame: &'static mut FighterAnimationFrame,
+    pub vulnerability: &'static mut FighterInvulnerabilityState,
+    pub ledge_information: &'static mut FighterLedgeInformation,
     pub fighter: &'static Fighter,
+    pub bone_matrices: &'static FighterBoneMatrices,
 }
 
 impl<'w, 's> FighterFrameQueryItem<'w, 's> {
@@ -244,14 +377,22 @@ impl<'w, 's> FighterFrameQueryItem<'w, 's> {
         animations: &'a FighterAnimations,
         baked_animations: &'a Assets<BakedFighterAnimations>,
         attributes: &'a FighterAttributes,
+        stage_collision: &'a StageCollision,
+        attack_scripts: &'a Assets<FighterAttackScript>,
+        attack_script_assets: &'a FighterAttackScriptAssets,
     ) -> InterruptContext<'a> {
         let animation = self.animation_status(animations, baked_animations);
         InterruptContext {
             input: &self.input,
             facing_direction: &mut self.facing_direction,
+            ledge_grab_lockout: &mut self.ledge_information,
             game_settings,
             fighter_attributes: attributes,
             animation,
+            surface: &self.surface,
+            stage_collision,
+            attack_script_assets: attack_script_assets,
+            attack_scripts,
         }
     }
 
@@ -259,23 +400,42 @@ impl<'w, 's> FighterFrameQueryItem<'w, 's> {
         &'a mut self,
         attributes: &'a FighterAttributes,
         attack_script_assets: &'a FighterAttackScriptAssets,
+        game_settings: &'a GameSettings,
+        stage_collision: &'a StageCollision,
+        baked_animations: &'a BakedFighterAnimations,
+        model_scale: FGi32,
     ) -> EnterContext<'a> {
         EnterContext {
             input: &mut self.input,
             hitboxes: &mut self.hitboxes,
             velocity: &mut self.velocity,
             knockback_velocity: &mut self.knockback_velocity,
+            knockback_state: &mut self.knockback_state,
+            translation: &mut self.translation,
             stale_move_queue: &mut self.stale_move_queue,
             facing_direction: &mut self.facing_direction,
             animation_frame: &mut self.animation_frame,
+            surface: &mut self.surface,
+            vulnerability: &mut self.vulnerability,
+            presentation_snap: &mut self.presentation_snap,
+            ledge_info: &mut self.ledge_information,
             fighter_attributes: attributes,
             attack_script_assets,
+            game_settings,
+            stage_collision,
+            baked_animations,
+            model_scale,
         }
     }
 
     fn exit_context(&mut self) -> ExitContext<'_> {
         ExitContext {
+            input: &mut self.input,
             hitboxes: &mut self.hitboxes,
+            knockback_velocity: &mut self.knockback_velocity,
+            knockback_state: &mut self.knockback_state,
+            surface: &mut self.surface,
+            vulnerability: &mut self.vulnerability,
         }
     }
 
@@ -285,34 +445,69 @@ impl<'w, 's> FighterFrameQueryItem<'w, 's> {
         attributes: &'a FighterAttributes,
         attack_scripts: &'a Assets<FighterAttackScript>,
         attack_script_assets: &'a FighterAttackScriptAssets,
+        stage_collision: &'a StageCollision,
     ) -> UpdateContext<'a> {
+        let animation_root_motion_delta = animation_position_to_gameplay(
+            self.bone_matrices.root_motion_delta(),
+            &self.facing_direction,
+        );
+        let animation_root_position = self
+            .bone_matrices
+            .root_motion_position()
+            .map(|_| self.translation.0 + animation_root_motion_delta);
         UpdateContext {
             translation: &mut self.translation,
             prev_translation: &mut self.prev_translation,
             input: &mut self.input,
             hitboxes: &mut self.hitboxes,
             velocity: &mut self.velocity,
+            surface: &mut self.surface,
             knockback_velocity: &mut self.knockback_velocity,
+            knockback_state: &mut self.knockback_state,
             game_settings,
+            animation_root_motion_delta,
+            animation_root_position,
             animation_frame: self.animation_frame.frame,
+            vulnerability: &mut self.vulnerability,
+            ledge_info: &mut self.ledge_information,
             fighter_attributes: attributes,
             attack_scripts,
             attack_script_assets,
-            facing_direction: &self.facing_direction
+            facing_direction: &self.facing_direction,
+            stage_collision: &stage_collision,
         }
     }
 
     fn collision_context<'a>(
         &'a mut self,
         stage_collision: &'a StageCollision,
+        fighter_manifest: &'a FighterManifest,
+        game_settings: &'a GameSettings,
     ) -> CollisionContext<'a> {
+        let fighter_ledge_collision_box = FGRect {
+            origin: self.translation.0 + fighter_manifest.ledge_grab_box_start,
+            end: self.translation.0 + fighter_manifest.ledge_grab_box_end,
+        };
         CollisionContext {
             translation: &mut self.translation,
             prev_translation: &self.prev_translation,
+            presentation_snap: &mut self.presentation_snap,
+            input: &self.input,
             velocity: &mut self.velocity,
-            ecb: &self.ecb,
+            knockback_velocity: &mut self.knockback_velocity,
+            knockback_state: &mut self.knockback_state,
+            surface: &mut self.surface,
+            ecb: &mut self.ecb,
+            desired_ecb: &mut self.desired_ecb,
+            ledge_info: &mut self.ledge_information,
             prev_ecb: &self.prev_ecb,
             stage_collision,
+            leave_ground_ecb_lock_duration: game_settings
+                .fighter_common
+                .leave_ground_ecb_frame_lock_duration,
+            downward_stick_threshold: game_settings.input_common.run_stick_threshold,
+            fighter_ledge_collision_box,
+            waveland_snap_distance: game_settings.fighter_common.waveland_snap_distance,
         }
     }
 }
@@ -325,14 +520,18 @@ pub struct StatefulFighterQuery {
     pub animations: &'static FighterAnimations,
     pub fighter: &'static Fighter,
     pub attack_script_assets: &'static FighterAttackScriptAssets,
+    pub player: &'static Player,
     pub pending_hit_reaction: &'static mut FighterPendingHitReaction,
     pub hitstop: &'static mut FighterHitstop,
     pub hitstop_shake: &'static mut FighterHitstopShake,
+    pub pending_respawn: &'static mut FighterPendingRespawn,
+    pub damage: &'static mut FighterDamage,
 }
 
 pub fn state_update_system(
     mut query: Query<StatefulFighterQuery>,
     game_settings: Res<GameSettings>,
+    stage_collision: Res<StageCollision>,
     attack_scripts: Res<Assets<FighterAttackScript>>,
     manifests: Res<Assets<FighterManifest>>,
 ) {
@@ -356,6 +555,7 @@ pub fn state_update_system(
             &manifest.attributes,
             &attack_scripts,
             &fighter.attack_script_assets,
+            &stage_collision,
         );
         state.update(&mut update_ctx);
     }
@@ -367,12 +567,31 @@ fn transition_state(
     frame: &mut FighterFrameQueryItem,
     attributes: &FighterAttributes,
     attack_script_assets: &FighterAttackScriptAssets,
+    stage_collision: &StageCollision,
+    game_settings: &GameSettings,
+    baked_animations: &BakedFighterAnimations,
+    model_scale: FGi32,
 ) {
     let old_name = current.name();
     let new_name = next.name();
 
     current.on_exit(&mut frame.exit_context());
-    next.on_enter(&mut frame.enter_context(attributes, attack_script_assets));
+    if let SurfacePolicy::Airborne(lock_policy) = next.surface_policy() {
+        frame.surface.apply_airborne_policy(
+            lock_policy,
+            game_settings
+                .fighter_common
+                .leave_ground_ecb_frame_lock_duration,
+        );
+    }
+    next.on_enter(&mut frame.enter_context(
+        attributes,
+        attack_script_assets,
+        game_settings,
+        stage_collision,
+        baked_animations,
+        model_scale,
+    ));
     *current = next;
     info!("{} -> {}", old_name, new_name);
 }
@@ -382,6 +601,8 @@ pub fn state_interrupt_system(
     game_settings: Res<GameSettings>,
     baked_animations: Res<Assets<BakedFighterAnimations>>,
     fighter_manifests: Res<Assets<FighterManifest>>,
+    attack_scripts: Res<Assets<FighterAttackScript>>,
+    stage_collision: Res<StageCollision>,
 ) {
     for fighter in &mut query {
         let StatefulFighterQueryItem {
@@ -393,14 +614,20 @@ pub fn state_interrupt_system(
             mut pending_hit_reaction,
             mut hitstop,
             mut hitstop_shake,
+            ..
         } = fighter;
         let manifest = fighter_manifests
             .get(&fighter.manifest)
             .expect("Fighter manifest should be valid");
+        let baked = baked_animations
+            .get(&animations.baked)
+            .expect("Animation should exist");
 
         let new_state = if let Some(reaction) = pending_hit_reaction.take() {
-            hitstop.remaining_frames = *reaction.hitstop_frames;
+            hitstop.remaining_frames = *reaction.victim_hitstop_frames;
-            let shake_frames = reaction.hitstop_frames.calculate_shake_frames(&game_settings);
+            let shake_frames = reaction
+                .victim_hitstop_frames
+                .calculate_shake_frames(&game_settings);
             hitstop_shake.role = FighterHitstopShakeRole::Receiver;
             hitstop_shake.total_frames = shake_frames;
             hitstop_shake.remaining_frames = shake_frames;
@@ -410,35 +637,25 @@ pub fn state_interrupt_system(
                 FighterHitstopShakeKind::Vertical
             };
 
-            let mut hitstop_kind = match &*state {
+            let mut hitstop_kind = if frame.surface.is_grounded() {
-                FighterState::Wait(value) => {
+                hitstun::HitstopStateKind::Grounded
-                    hitstun::HitstopStateKind::Grounded(value.grounded_common.clone())
+            } else {
-                }
+                hitstun::HitstopStateKind::Airborne
-                FighterState::Walk(value) => {
-                    hitstun::HitstopStateKind::Grounded(value.grounded_common.clone())
-                }
-                FighterState::Dash(value) => {
-                    hitstun::HitstopStateKind::Grounded(value.ground_common.clone())
-                }
-                FighterState::Run(value) => {
-                    hitstun::HitstopStateKind::Grounded(value.grounded_common.clone())
-                }
-                FighterState::Turn(value) => {
-                    hitstun::HitstopStateKind::Grounded(value.grounded_common.clone())
-                }
-                FighterState::GroundAttack(value) => {
-                    hitstun::HitstopStateKind::Grounded(value.grounded_common.clone())
-                }
-                _ => hitstun::HitstopStateKind::Airborne,
             };
 
-            if let hitstun::HitstopStateKind::Grounded(_) = hitstop_kind {
+            if let hitstun::HitstopStateKind::Grounded = hitstop_kind {
                 let straight_up_angle = FGi32::lit("90.0");
-                if reaction.hitstop_frames >= HitStop::new(game_settings.fighter_common.tumble_bounce_hitstop_threshold) {
+                if reaction.victim_hitstop_frames
+                    >= HitStop::new(game_settings.fighter_common.tumble_bounce_hitstop_threshold)
+                {
                     hitstop_kind = hitstun::HitstopStateKind::Airborne;
                 // TODO: Use floor normal here
-                } else if reaction.launch_angle.abs_diff(straight_up_angle) < game_settings.fighter_common.attack_ground_to_airborne_transition_vertical_angle_threshold {
+                } else if reaction.launch_angle.abs_diff(straight_up_angle)
-                        hitstop_kind = hitstun::HitstopStateKind::Airborne;
+                    < game_settings
+                        .fighter_common
+                        .attack_ground_to_airborne_transition_vertical_angle_threshold
+                {
+                    hitstop_kind = hitstun::HitstopStateKind::Airborne;
                 } else {
                     // straight down is 270
                     let straight_down_angle = FGi32::lit("270.0");
@@ -451,9 +668,16 @@ pub fn state_interrupt_system(
             }
 
             info!("Entering hitstop kind: {:?}", hitstop_kind);
+            let stack_previous_knockback = !frame.surface.is_grounded()
+                && !frame.knockback_velocity.0.length_squared().is_zero()
+                && frame
+                    .knockback_state
+                    .can_stack(game_settings.fighter_common.knockback_stacking_window);
+
             Some(FighterState::Hitstun(HitstunState::new(
                 reaction,
                 hitstop_kind,
+                stack_previous_knockback,
             )))
         } else if hitstop.remaining_frames > 0 {
             None
@@ -463,6 +687,9 @@ pub fn state_interrupt_system(
                 animations,
                 &baked_animations,
                 &manifest.attributes,
+                &stage_collision,
+                &attack_scripts,
+                attack_script_assets,
             ))
         };
 
@@ -473,6 +700,10 @@ pub fn state_interrupt_system(
                 &mut frame,
                 &manifest.attributes,
                 attack_script_assets,
+                &stage_collision,
+                &game_settings,
+                baked,
+                manifest.model_scale,
             );
         };
     }
@@ -482,25 +713,107 @@ pub fn state_collision_interrupt_system(
     mut query: Query<StatefulFighterQuery>,
     stage_collision: Res<StageCollision>,
     fighter_manifests: Res<Assets<FighterManifest>>,
+    game_settings: Res<GameSettings>,
+    match_config: Res<MatchConfig>,
+    mut match_state: ResMut<MatchState>,
+    stage_registry: Res<StageManifestRegistry>,
+    stage_manifests: Res<Assets<StageManifest>>,
+    baked_animations: Res<Assets<BakedFighterAnimations>>,
 ) {
+    let Some(stage_manifest_handle) = stage_registry.get(match_config.stage) else {
+        return;
+    };
+
+    let Some(stage_manifest) = stage_manifests.get(&stage_manifest_handle) else {
+        return;
+    };
+
     for fighter in &mut query {
         let StatefulFighterQueryItem {
             mut state,
             mut frame,
             fighter,
+            animations,
             attack_script_assets,
-            hitstop,
+            mut hitstop,
+            mut pending_respawn,
+            player,
+            mut damage,
             ..
         } = fighter;
-        if hitstop.remaining_frames > 0 {
-            continue;
-        }
 
         let manifest = fighter_manifests
             .get(&fighter.manifest)
             .expect("Fighter manifest should be valid");
-        let new_state =
+        let baked = baked_animations
-            state.check_collision_interrupt(&mut frame.collision_context(&stage_collision));
+            .get(&animations.baked)
+            .expect("Animation should exist");
+
+        if pending_respawn.0 {
+            **pending_respawn = false;
+            let respawn_state = FighterState::Angel(angel::AngelState::new(
+                game_settings
+                    .fighter_common
+                    .angel_platform_invulnerability_duration,
+            ));
+
+            // Find the angel platform position
+            let respawn_point = stage_manifest
+                .respawn_points
+                .get(player.controller_port % stage_manifest.respawn_points.len());
+
+            if let None = respawn_point {
+                error!("Couldn't get a respawn point, falling back to the world origin");
+            }
+
+            let respawn_point = respawn_point.copied().unwrap_or(FGVec2::ZERO);
+
+            frame.translation.0 = respawn_point;
+            frame.presentation_snap.0 = true;
+
+            // Clear hitstop
+            hitstop.remaining_frames = 0;
+            frame.knockback_velocity.0 = FGVec2::ZERO;
+            frame.knockback_state.clear();
+
+            // subtract one stock
+
+            let player_state = match_state.players.get_mut(player.handle).expect(&format!(
+                "Failed to get fighter for GGRS slot {} (controller port {})",
+                player.handle, player.controller_port
+            ));
+
+            if let Some(stocks_remaining) = &mut player_state.stocks_remaining {
+                *stocks_remaining = stocks_remaining.saturating_sub(1);
+            }
+
+            // reset percentage
+            *damage = FighterDamage::default();
+            // reset ledge
+
+            *frame.ledge_information = FighterLedgeInformation::default();
+
+            transition_state(
+                &mut state,
+                respawn_state,
+                &mut frame,
+                &manifest.attributes,
+                attack_script_assets,
+                &stage_collision,
+                &game_settings,
+                baked,
+                manifest.model_scale,
+            );
+            continue;
+        }
+
+        if hitstop.remaining_frames > 0 {
+            continue;
+        }
+
+        let new_state = state.check_collision_interrupt(
+            &mut frame.collision_context(&stage_collision, manifest, &game_settings),
+        );
         if let Some(new_state) = new_state {
             transition_state(
                 &mut state,
@@ -508,7 +821,97 @@ pub fn state_collision_interrupt_system(
                 &mut frame,
                 &manifest.attributes,
                 &attack_script_assets,
+                &stage_collision,
+                &game_settings,
+                baked,
+                manifest.model_scale,
             );
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::fighter::ecb::FighterPreviousECB;
+    use crate::stage::line::{StageLedge, StageLedgeSide, StageVertexID};
+
+    #[test]
+    fn animation_positions_map_forward_to_facing_and_preserve_height() {
+        let position = FGVec3::lit("99", "3", "5");
+
+        assert_eq!(
+            animation_position_to_gameplay(position, &FighterFacingDirection::Right),
+            FGVec2::lit("5", "3")
+        );
+        assert_eq!(
+            animation_position_to_gameplay(position, &FighterFacingDirection::Left),
+            FGVec2::lit("-5", "3")
+        );
+    }
+
+    #[test]
+    fn ledge_lockout_suppresses_ledge_collision() {
+        let ledge_id = StageVertexID {
+            polygon: 0,
+            vertex: 0,
+        };
+        let stage_collision = StageCollision {
+            ledges: vec![StageLedge {
+                id: ledge_id,
+                position: FGVec2::ZERO,
+                hang_side: StageLedgeSide::Left,
+            }],
+            ..default()
+        };
+        let previous_translation = FighterPreviousTranslation::default();
+        let input = FighterInput::default();
+        let mut translation = FighterTranslation::default();
+        let mut velocity = FighterVelocity::default();
+        let mut knockback_velocity = FighterKnockbackVelocity::default();
+        let mut knockback_state = FighterKnockbackState::default();
+        let mut surface = FighterSurfaceState::default();
+        let mut ecb = FighterECB::default();
+        let mut desired_ecb = FighterDesiredECB {
+            top: FGVec2::lit("0", "2"),
+            bottom: FGVec2::ZERO,
+            left: FGVec2::lit("-1", "1"),
+            right: FGVec2::lit("1", "1"),
+        };
+        let mut ledge_info = FighterLedgeInformation {
+            regrab_lockout_remaining_frames: 5,
+            ..default()
+        };
+        let previous_ecb = FighterPreviousECB::from(ecb);
+        let mut presentation_snap = FighterPresentationSnap::default();
+        let context = CollisionContext {
+            translation: &mut translation,
+            prev_translation: &previous_translation,
+            input: &input,
+            velocity: &mut velocity,
+            knockback_velocity: &mut knockback_velocity,
+            knockback_state: &mut knockback_state,
+            surface: &mut surface,
+            ecb: &mut ecb,
+            desired_ecb: &mut desired_ecb,
+            ledge_info: &mut ledge_info,
+            prev_ecb: &previous_ecb,
+            stage_collision: &stage_collision,
+            leave_ground_ecb_lock_duration: 0,
+            presentation_snap: &mut presentation_snap,
+            fighter_ledge_collision_box: FGRect {
+                origin: FGVec2::lit("-1", "1"),
+                end: FGVec2::lit("1", "-1"),
+            },
+            downward_stick_threshold: FGi32::ONE,
+            waveland_snap_distance: FGi32::ZERO,
+        };
+
+        assert!(context.air_collide_with_ledges().is_none());
+        context.ledge_info.regrab_lockout_remaining_frames = 0;
+        assert_eq!(
+            context.air_collide_with_ledges().map(|result| result.ledge),
+            Some(ledge_id)
+        );
+    }
+}

src/fighter/state/platform_pass.rs

@@ -0,0 +1,65 @@
+use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
+use crate::fighter::animation::AnimKind;
+use crate::fighter::state::air::AirborneStateCommon;
+use crate::fighter::state::{ExitContext, FighterState, air, jump};
+
+#[derive(Debug, Clone, Copy, Hash, Default)]
+pub struct PlatformPassState {
+    airborne_state_common: AirborneStateCommon,
+    ignored_polygon: usize,
+}
+
+impl PlatformPassState {
+    pub fn new(airborne_state_common: AirborneStateCommon, ignored_polygon: usize) -> Self {
+        Self {
+            airborne_state_common,
+            ignored_polygon
+        }
+    }
+}
+
+impl FighterStateImpl for PlatformPassState {
+    const NAME: &'static str = "PlatformPass";
+    
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
+        jump::check_input_double_jump(state_context)
+    }
+
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context.surface.ignore_polygon(self.ignored_polygon, state_context.game_settings.fighter_common.platform_pass_platform_ignore_duration_frames);
+        state_context.velocity.y = state_context.game_settings.fighter_common.platform_pass_initial_downwards_velocity;
+        state_context.play_animation(AnimKind::PlatformPass, false);
+    }
+
+    fn on_exit(&mut self, state_context: &mut ExitContext) {
+        state_context.surface.clear_polygon_ignore(self.ignored_polygon);
+    }
+
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        air::update_standard_motion(state_context, &mut self.airborne_state_common);
+    }
+
+    fn check_collision_interrupt(
+        &mut self,
+        state_context: &mut CollisionContext,
+    ) -> Option<FighterState> {
+        air::collision_interrupt(
+            state_context,
+            crate::fighter::state::land::LandingType::Normal,
+            crate::fighter::collision::AirCollisionOptions {
+                can_pass_through_soft_platforms: true,
+                ..Default::default()
+            },
+        )
+    }
+    
+    fn is_visually_grounded<'a>(
+        &'a self,
+    ) -> bool {
+        false
+    }
+
+    fn surface_policy(&self) -> super::SurfacePolicy {
+        super::SurfacePolicy::Airborne(crate::fighter::surface::EcbLockPolicy::StartOnDetach)
+    }
+}

src/fighter/state/run.rs

@@ -6,19 +6,14 @@ use super::{
 };
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::FighterState;
-use crate::fighter::state::ground::GroundedStateCommon;
 
 #[derive(Component, Debug, Clone, Hash)]
-pub struct RunState {
+pub struct RunState;
-    pub grounded_common: GroundedStateCommon,
-}
 
 impl FighterStateImpl for RunState {
     const NAME: &'static str = "Run";
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
-        if let Some(state) =
+        if let Some(state) = ground::grounded_movement_common_interrupts(state_context) {
-            ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
-        {
             return Some(state);
         }
 
@@ -28,8 +23,7 @@ impl FighterStateImpl for RunState {
         {
             None
         } else {
-            walk::check_input(state_context, &self.grounded_common)
+            walk::check_input(state_context).or_else(|| wait::check_input(state_context))
-                .or_else(|| wait::check_input(state_context, &self.grounded_common))
         }
     }
 
@@ -54,7 +48,6 @@ impl FighterStateImpl for RunState {
         ground::apply_grounded_motion(
             state_context.velocity,
             state_context.translation,
-            state_context.prev_translation,
         );
     }
 
@@ -62,26 +55,19 @@ impl FighterStateImpl for RunState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.grounded_common, true)
+        ground::collision_interrupt(state_context, true)
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }
 
-pub fn check_input(
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context: &InterruptContext,
-    ground_state_common: &GroundedStateCommon,
-) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();
     if input_frame.movement.x.abs() >= state_context.game_settings.input_common.run_stick_threshold
     {
-        return Some(FighterState::Run(RunState {
+        return Some(FighterState::Run(RunState));
-            grounded_common: ground_state_common.clone(),
-        }));
     }
     None
 }

src/fighter/state/turn.rs

@@ -1,13 +1,11 @@
 use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
 use crate::fighter::animation::AnimKind;
-use crate::fighter::state::ground::{self, GroundedStateCommon};
+use crate::fighter::state::ground;
 use crate::fighter::state::{FighterState, dash, jump, wait, walk};
 use crate::input::FighterCommands;
 
 #[derive(Debug, Clone, Hash)]
-pub struct TurnState {
+pub struct TurnState;
-    pub grounded_common: GroundedStateCommon,
-}
 
 impl FighterStateImpl for TurnState {
     const NAME: &'static str = "Turn";
@@ -19,19 +17,19 @@ impl FighterStateImpl for TurnState {
                 .input_common
                 .turn_into_dashback_window as u32
         {
-            if let Some(state) = dash::check_input(state_context, &self.grounded_common) {
+            if let Some(state) = dash::check_input(state_context) {
                 return Some(state);
             }
         }
-        if let Some(state) = jump::check_input(state_context, &self.grounded_common) {
+        if let Some(state) = jump::check_input(state_context) {
             *state_context.facing_direction = state_context.facing_direction.reverse();
             Some(state)
         } else if state_context.is_current_animation_finished() {
-            if let Some(state) = dash::check_input(state_context, &self.grounded_common) {
+            if let Some(state) = dash::check_input(state_context) {
                 Some(state)
-            } else if let Some(state) = walk::check_input(state_context, &self.grounded_common) {
+            } else if let Some(state) = walk::check_input(state_context) {
                 Some(state)
-            } else if let Some(state) = wait::check_input(state_context, &self.grounded_common) {
+            } else if let Some(state) = wait::check_input(state_context) {
                 Some(state)
             } else {
                 None
@@ -54,20 +52,15 @@ impl FighterStateImpl for TurnState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
+        ground::collision_interrupt(state_context, false)
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }
 
-pub fn check_input(
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context: &InterruptContext,
-    grounded_common: &GroundedStateCommon,
-) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();
 
     let has_smash_input = state_context
@@ -81,9 +74,7 @@ pub fn check_input(
         && input_frame.movement.x.signum() != state_context.facing_direction.to_sign()
         && !has_smash_input
     {
-        return Some(FighterState::Turn(TurnState {
+        return Some(FighterState::Turn(TurnState));
-            grounded_common: grounded_common.clone(),
-        }));
     }
     None
 }

src/fighter/state/wait.rs

@@ -3,24 +3,18 @@ use super::{
 };
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::FighterState;
-use crate::fighter::state::ground::GroundedStateCommon;
 
 #[derive(Debug, Clone, Hash)]
-pub struct WaitState {
+pub struct WaitState;
-    pub grounded_common: GroundedStateCommon,
-}
 
 impl FighterStateImpl for WaitState {
     const NAME: &'static str = "Wait";
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
-        if let Some(state) =
+        if let Some(state) = ground::grounded_movement_common_interrupts(state_context) {
-            ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
-        {
             Some(state)
-        } else if let Some(state) = ground::grounded_movement_standstill_common_interrupts(
+        } else if let Some(state) =
-            state_context,
+            ground::grounded_movement_standstill_common_interrupts(state_context)
-            &self.grounded_common,
+        {
-        ) {
             // Don't transition into yourself
             if let FighterState::Wait(_) = state {
                 None
@@ -44,26 +38,19 @@ impl FighterStateImpl for WaitState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
+        ground::collision_interrupt(state_context, false)
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }
 
-pub fn check_input(
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context: &InterruptContext,
-    ground_state_common: &GroundedStateCommon,
-) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();
 
     if input_frame.movement.x.abs() < state_context.game_settings.input_common.stick_deadzone {
-        return Some(FighterState::Wait(WaitState {
+        return Some(FighterState::Wait(WaitState));
-            grounded_common: ground_state_common.clone(),
-        }));
     }
     None
 }

src/fighter/state/walk.rs

@@ -3,24 +3,18 @@ use super::{
     ground, wait,
 };
 use crate::fighter::animation::AnimKind;
-use crate::fighter::state::FighterState;
+use crate::fighter::state::{self, FighterState};
-use crate::fighter::state::ground::GroundedStateCommon;
 
 #[derive(Debug, Clone, Hash)]
-pub struct WalkState {
+pub struct WalkState;
-    pub grounded_common: GroundedStateCommon,
-}
 
 impl FighterStateImpl for WalkState {
     const NAME: &'static str = "Walk";
     fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
-        if let Some(state) =
+        if let Some(state) = ground::grounded_movement_common_interrupts(state_context) {
-            ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
-        {
             return Some(state);
         }
-        wait::check_input(state_context, &self.grounded_common)
+        wait::check_input(state_context).or_else(|| dash::check_input(state_context)).or_else(|| state::ground_attack::check_interrupt(state_context))
-            .or_else(|| dash::check_input(state_context, &self.grounded_common))
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
@@ -46,7 +40,6 @@ impl FighterStateImpl for WalkState {
         ground::apply_grounded_motion(
             state_context.velocity,
             state_context.translation,
-            state_context.prev_translation,
         );
     }
 
@@ -54,26 +47,19 @@ impl FighterStateImpl for WalkState {
         &mut self,
         state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
+        ground::collision_interrupt(state_context, false)
     }
 
-    fn is_visually_grounded<'a>(
+    fn is_visually_grounded<'a>(&'a self) -> bool {
-        &'a self,
-    ) -> bool {
         true
     }
 }
 
-pub fn check_input(
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
-    state_context: &InterruptContext,
-    ground_state_common: &GroundedStateCommon,
-) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();
 
     if !input_frame.movement.x.is_zero() {
-        return Some(FighterState::Walk(WalkState {
+        return Some(FighterState::Walk(WalkState));
-            grounded_common: ground_state_common.clone(),
-        }));
     }
 
     None

src/fighter/surface.rs

@@ -0,0 +1,235 @@
+use bevy::prelude::*;
+
+use crate::{fighter::FighterLedgeInformation, stage::line::StageLineID};
+
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
+pub enum EcbLockPolicy {
+    StartOnDetach,
+    Restart,
+    Preserve,
+    Clear,
+}
+
+/// The stage surface currently supporting a fighter.
+///
+/// This is physics state rather than fighter-state-machine state. Keeping it
+/// separate means grounded, landing, and hitstun states all share one source
+/// of truth for stage contact.
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+pub struct IgnoredPolygon {
+    pub polygon: usize,
+    pub frames_remaining: u32,
+}
+
+#[derive(Component, Clone, Debug, Hash, PartialEq, Eq)]
+pub enum FighterSurfaceState {
+    Airborne {
+        ecb_lock_frames_remaining: u32,
+        ignored_polys: Vec<IgnoredPolygon>,
+    },
+    Grounded {
+        line_id: StageLineID,
+    },
+}
+
+impl Default for FighterSurfaceState {
+    fn default() -> Self {
+        Self::Airborne {
+            ecb_lock_frames_remaining: 0,
+            ignored_polys: vec![],
+        }
+    }
+}
+
+impl FighterSurfaceState {
+    pub fn is_grounded(&self) -> bool {
+        matches!(self, Self::Grounded { .. })
+    }
+
+    pub fn line_id(&self) -> Option<StageLineID> {
+        match self {
+            Self::Airborne { .. } => None,
+            Self::Grounded { line_id } => Some(*line_id),
+        }
+    }
+
+    pub(crate) fn land(&mut self, line_id: StageLineID, ledge_info: &mut FighterLedgeInformation) {
+        *self = Self::Grounded { line_id };
+        ledge_info.grab_count = 0;
+    }
+
+    pub fn clear_polygon_ignore(&mut self, polygon: usize) {
+        let Self::Airborne { ignored_polys, .. } = self else {
+            return;
+        };
+
+        ignored_polys.retain(|element| element.polygon != polygon);
+    }
+    
+    pub fn ignore_polygon(&mut self, polygon: usize, duration_frames: u32) {
+        let Self::Airborne { ignored_polys, .. } = self else {
+            return;
+        };
+
+        if duration_frames == 0 {
+            return;
+        }
+
+        if let Some(ignored) = ignored_polys.iter_mut().find(|ignored| ignored.polygon == polygon) {
+            ignored.frames_remaining = duration_frames;
+        } else {
+            ignored_polys.push(IgnoredPolygon {
+                polygon,
+                frames_remaining: duration_frames,
+            });
+        }
+    }
+
+    pub fn is_polygon_ignored(&self, polygon: usize) -> bool {
+        matches!(self, Self::Airborne { ignored_polys, .. }
+            if ignored_polys.iter().any(|ignored| ignored.polygon == polygon))
+    }
+
+    pub(crate) fn ignored_polygon_ids(&self) -> Vec<usize> {
+        match self {
+            Self::Airborne { ignored_polys, .. } => {
+                ignored_polys.iter().map(|ignored| ignored.polygon).collect()
+            }
+            Self::Grounded { .. } => vec![],
+        }
+    }
+
+    pub(crate) fn apply_airborne_policy(
+        &mut self,
+        policy: EcbLockPolicy,
+        ecb_lock_duration: u32,
+    ) {
+        let current_lock = match self {
+            Self::Airborne { ecb_lock_frames_remaining, .. } => *ecb_lock_frames_remaining,
+            Self::Grounded { .. } => 0,
+        };
+        let ecb_lock_frames_remaining = match policy {
+            EcbLockPolicy::StartOnDetach if self.is_grounded() => ecb_lock_duration,
+            EcbLockPolicy::StartOnDetach => current_lock,
+            EcbLockPolicy::Restart => ecb_lock_duration,
+            EcbLockPolicy::Preserve => current_lock,
+            EcbLockPolicy::Clear => 0,
+        };
+        let ignored_polys = match self {
+            Self::Airborne { ignored_polys, .. } => ignored_polys.clone(),
+            Self::Grounded { .. } => vec![],
+        };
+        *self = Self::Airborne { ecb_lock_frames_remaining, ignored_polys };
+    }
+
+    pub(crate) fn tick_ecb_lock(&mut self) {
+        if let Self::Airborne { ecb_lock_frames_remaining, .. } = self {
+            *ecb_lock_frames_remaining = ecb_lock_frames_remaining.saturating_sub(1);
+        }
+    }
+
+    pub(crate) fn tick_ignored_polygons(&mut self) {
+        if let Self::Airborne { ignored_polys, .. } = self {
+            for ignored in ignored_polys.iter_mut() {
+                ignored.frames_remaining = ignored.frames_remaining.saturating_sub(1);
+            }
+            ignored_polys.retain(|ignored| ignored.frames_remaining > 0);
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn contact_lifecycle_has_one_source_of_truth() {
+        let mut surface = FighterSurfaceState::default();
+        assert!(!surface.is_grounded());
+        assert_eq!(surface.line_id(), None);
+
+        let line_id = StageLineID {
+            polygon: 2,
+            segment: 3,
+        };
+        let mut ledge_info = FighterLedgeInformation {
+            regrab_lockout_remaining_frames: 0,
+            grab_count: 0,
+        };
+        surface.land(line_id, &mut ledge_info);
+        assert!(surface.is_grounded());
+        assert_eq!(surface.line_id(), Some(line_id));
+
+        surface.apply_airborne_policy(EcbLockPolicy::Clear, 0);
+        assert!(!surface.is_grounded());
+        assert_eq!(surface.line_id(), None);
+    }
+
+    #[test]
+    fn start_on_detach_does_not_reset_an_existing_lock() {
+        let mut surface = FighterSurfaceState::default();
+        surface.apply_airborne_policy(EcbLockPolicy::Restart, 5);
+        surface.tick_ecb_lock();
+        surface.apply_airborne_policy(EcbLockPolicy::StartOnDetach, 5);
+
+        assert_eq!(
+            surface,
+            FighterSurfaceState::Airborne {
+                ecb_lock_frames_remaining: 4,
+                ignored_polys: vec![],
+            }
+        );
+    }
+
+    #[test]
+    fn restart_retriggers_an_existing_lock() {
+        let mut surface = FighterSurfaceState::default();
+        surface.apply_airborne_policy(EcbLockPolicy::Restart, 5);
+        surface.tick_ecb_lock();
+        surface.apply_airborne_policy(EcbLockPolicy::Restart, 5);
+
+        assert_eq!(
+            surface,
+            FighterSurfaceState::Airborne {
+                ecb_lock_frames_remaining: 5,
+                ignored_polys: vec![],
+            }
+        );
+    }
+
+    #[test]
+    fn ignored_polygon_expires_after_requested_frames() {
+        let mut surface = FighterSurfaceState::default();
+        surface.ignore_polygon(3, 2);
+
+        assert!(surface.is_polygon_ignored(3));
+        surface.tick_ignored_polygons();
+        assert!(surface.is_polygon_ignored(3));
+        surface.tick_ignored_polygons();
+        assert!(!surface.is_polygon_ignored(3));
+    }
+
+    #[test]
+    fn ignoring_polygon_refreshes_existing_entry() {
+        let mut surface = FighterSurfaceState::default();
+        surface.ignore_polygon(3, 2);
+        surface.ignore_polygon(3, 5);
+        surface.tick_ignored_polygons();
+        surface.tick_ignored_polygons();
+        assert!(surface.is_polygon_ignored(3));
+    }
+
+    #[test]
+    fn airborne_policy_preserves_ignored_polygons_and_landing_clears_them() {
+        let mut surface = FighterSurfaceState::default();
+        surface.ignore_polygon(3, 5);
+        surface.apply_airborne_policy(EcbLockPolicy::Restart, 2);
+        assert!(surface.is_polygon_ignored(3));
+        let mut ledge_info = FighterLedgeInformation {
+            regrab_lockout_remaining_frames: 0,
+            grab_count: 0,
+        };
+        surface.land(StageLineID { polygon: 0, segment: 0 }, &mut ledge_info);
+        assert!(!surface.is_polygon_ignored(3));
+    }
+}

src/fighter/visual.rs

@@ -1,4 +1,8 @@
-use crate::fighter::baked_animation::BakedFighterAnimations;
+use crate::{
+    fighter::{FighterInvulnerabilityState, baked_animation::BakedFighterAnimations},
+    game_settings::GameSettings,
+    materials::fighter_material::{FighterMaterial, FighterMesh},
+};
 use bevy::prelude::*;
 
 #[derive(Component, Clone)]
@@ -6,3 +10,82 @@ pub struct FighterAnimations {
     /// The single animation source for gameplay and the visual skeleton.
     pub baked: Handle<BakedFighterAnimations>,
 }
+
+#[derive(Clone, Copy, Default, PartialEq)]
+pub enum LastKnownInvulnerabilityState {
+    #[default]
+    Vulnerable,
+    Intangible,
+    Invulnerable,
+}
+
+impl From<&FighterInvulnerabilityState> for LastKnownInvulnerabilityState {
+    fn from(value: &FighterInvulnerabilityState) -> Self {
+        match value {
+            FighterInvulnerabilityState::Vulnerable => Self::Vulnerable,
+            FighterInvulnerabilityState::Invulnerable { .. } => Self::Invulnerable,
+            FighterInvulnerabilityState::Intangible { .. } => Self::Intangible,
+        }
+    }
+}
+
+#[derive(Component, Clone, Default)]
+pub struct FighterInvulnerabilityVisualState {
+    pub last_known_state: LastKnownInvulnerabilityState,
+    pub frames_in_state: u32,
+}
+
+pub fn update_status_colors(
+    mut fighters: Query<(
+        &FighterInvulnerabilityState,
+        &mut FighterInvulnerabilityVisualState,
+    )>,
+    meshes: Query<(&FighterMesh, &MeshMaterial3d<FighterMaterial>)>,
+    mut materials: ResMut<Assets<FighterMaterial>>,
+    game_settings: Res<GameSettings>,
+) {
+    for (invuln_state, mut invuln_state_visual) in &mut fighters {
+        let curr_state = invuln_state.into();
+        let last_known_state = invuln_state_visual.last_known_state;
+        if curr_state != last_known_state {
+            invuln_state_visual.last_known_state = curr_state;
+            invuln_state_visual.frames_in_state = 0;
+        }
+    }
+    for (mesh, mat) in meshes {
+        let (_, invuln_state_visual) = fighters
+            .get(mesh.fighter)
+            .expect("Material should have relevant fighter available");
+
+        let status_color = match invuln_state_visual.last_known_state {
+            LastKnownInvulnerabilityState::Vulnerable => bevy::color::palettes::css::WHITE.into(),
+            LastKnownInvulnerabilityState::Invulnerable => {
+                game_settings.fighter_common.intangible_color
+            }
+            LastKnownInvulnerabilityState::Intangible => {
+                game_settings.fighter_common.intangible_color
+            }
+        };
+
+        let intensity = match invuln_state_visual.last_known_state {
+            LastKnownInvulnerabilityState::Vulnerable => 0.0,
+            LastKnownInvulnerabilityState::Invulnerable | LastKnownInvulnerabilityState::Intangible => {
+                let cycle_frames = invuln_state_visual.frames_in_state
+                    % game_settings.fighter_common.intangible_pulse_duration;
+                1.0 - cycle_frames as f32
+                    / ((game_settings.fighter_common.intangible_pulse_duration) as f32)
+            }
+        };
+
+        let mut material = materials
+            .get_mut(mat.id())
+            .expect("Material should exist here...");
+        material
+            .extension
+            .update_status_color(status_color.into(), intensity);
+    }
+
+    for (_, mut invuln_state_visual) in fighters {
+        invuln_state_visual.frames_in_state = invuln_state_visual.frames_in_state.saturating_add(1);
+    }
+}

src/filled_gizmo.wgsl

@@ -0,0 +1,30 @@
+#import bevy_pbr::mesh_functions::{get_world_from_local, mesh_position_local_to_clip}
+
+@group(#{MATERIAL_BIND_GROUP}) @binding(0) var<uniform> material_color: vec4<f32>;
+
+struct Vertex {
+    @builtin(instance_index) instance_index: u32,
+    @location(0) position: vec3<f32>,
+    @location(1) color: vec4<f32>,
+};
+
+struct VertexOutput {
+    @builtin(position) clip_position: vec4<f32>,
+    @location(0) color: vec4<f32>,
+};
+
+@vertex
+fn vertex(vertex: Vertex) -> VertexOutput {
+    var output: VertexOutput;
+    output.clip_position = mesh_position_local_to_clip(
+        get_world_from_local(vertex.instance_index),
+        vec4<f32>(vertex.position, 1.0),
+    );
+    output.color = vertex.color;
+    return output;
+}
+
+@fragment
+fn fragment(input: VertexOutput) -> @location(0) vec4<f32> {
+    return material_color * input.color;
+}

src/filled_gizmos.rs

@@ -0,0 +1,417 @@
+//! Immediate-mode filled debug geometry.
+//!
+//! Unlike Bevy's line-only `Gizmos`, this collects triangles into one dynamic
+//! mesh. It is intended for small, transient debug overlays rather than game
+//! geometry.
+
+use std::f32::consts::{FRAC_PI_2, PI, TAU};
+
+use bevy::{
+    asset::{load_internal_asset, uuid_handle, RenderAssetUsages},
+    camera::visibility::NoFrustumCulling,
+    ecs::system::SystemParam,
+    mesh::{Indices, MeshVertexBufferLayoutRef, PrimitiveTopology},
+    pbr::{MaterialPipeline, MaterialPipelineKey},
+    prelude::*,
+    render::render_resource::{
+        AsBindGroup, RenderPipelineDescriptor, SpecializedMeshPipelineError,
+    },
+    shader::ShaderRef,
+};
+
+const SPHERE_SECTORS: usize = 16;
+const SPHERE_STACKS: usize = 8;
+const CAPSULE_SECTORS: usize = 16;
+const CAPSULE_HEMISPHERE_STEPS: usize = 4;
+
+#[derive(Default)]
+struct FilledGizmoGeometry {
+    positions: Vec<[f32; 3]>,
+    normals: Vec<[f32; 3]>,
+    colors: Vec<[f32; 4]>,
+    indices: Vec<u32>,
+}
+
+#[derive(Resource, Default)]
+struct FilledGizmoBuffer {
+    /// Geometry requested by the current schedule invocation.
+    pending: FilledGizmoGeometry,
+    /// The last completed fixed-timestep geometry. This is retained between
+    /// render frames, just like Bevy's fixed-timestep gizmos.
+    retained: FilledGizmoGeometry,
+    mesh: Option<Handle<Mesh>>,
+    fixed_commit: bool,
+}
+
+/// Immediate-mode API for drawing filled debug shapes.
+#[derive(SystemParam)]
+pub struct FilledGizmos<'w> {
+    buffer: ResMut<'w, FilledGizmoBuffer>,
+}
+
+impl FilledGizmos<'_> {
+    /// Draw a filled planar polygon. Vertices must be ordered around the
+    /// perimeter and the polygon must be convex.
+    pub fn polygon(&mut self, vertices: &[Vec3], color: impl Into<Color> + Copy) {
+        if vertices.len() < 3 {
+            return;
+        }
+        let color = color.into().to_linear().to_f32_array();
+        let normal = (vertices[1] - vertices[0])
+            .cross(vertices[2] - vertices[0])
+            .normalize_or_zero();
+        let base = self.buffer.pending.positions.len() as u32;
+        for &vertex in vertices {
+            self.push_vertex(vertex, normal, color);
+        }
+        for index in 2..vertices.len() as u32 {
+            self.buffer
+                .pending
+                .indices
+                .extend([base, base + index - 1, base + index]);
+        }
+    }
+
+    pub fn sphere(&mut self, isometry: Isometry3d, radius: f32, color: impl Into<Color> + Copy) {
+        if radius <= 0.0 {
+            return;
+        }
+        let color = color.into().to_linear().to_f32_array();
+        let base = self.buffer.pending.positions.len() as u32;
+        for stack in 0..=SPHERE_STACKS {
+            let latitude = PI * 0.5 - stack as f32 * PI / SPHERE_STACKS as f32;
+            let (sin_lat, cos_lat) = latitude.sin_cos();
+            for sector in 0..=SPHERE_SECTORS {
+                let longitude = sector as f32 * TAU / SPHERE_SECTORS as f32;
+                let (sin_lon, cos_lon) = longitude.sin_cos();
+                let normal = Vec3::new(cos_lat * cos_lon, sin_lat, cos_lat * sin_lon);
+                self.push_vertex(
+                    isometry.transform_point(normal * radius).into(),
+                    isometry.rotation * normal,
+                    color,
+                );
+            }
+        }
+        let stride = SPHERE_SECTORS + 1;
+        for stack in 0..SPHERE_STACKS {
+            for sector in 0..SPHERE_SECTORS {
+                let a = base + (stack * stride + sector) as u32;
+                let b = a + stride as u32;
+                self.buffer
+                    .pending
+                    .indices
+                    .extend([a, b, a + 1, a + 1, b, b + 1]);
+            }
+        }
+    }
+
+    pub fn capsule(
+        &mut self,
+        isometry: Isometry3d,
+        radius: f32,
+        half_length: f32,
+        color: impl Into<Color> + Copy,
+    ) {
+        let transform = Mat4::from_scale_rotation_translation(
+            Vec3::ONE,
+            isometry.rotation,
+            isometry.translation.into(),
+        );
+        self.affine_capsule(transform, radius, half_length, color);
+    }
+
+    /// Draw a capsule transformed by an arbitrary affine transform.
+    pub fn affine_capsule(
+        &mut self,
+        transform: Mat4,
+        radius: f32,
+        half_length: f32,
+        color: impl Into<Color> + Copy,
+    ) {
+        if radius <= 0.0 {
+            return;
+        }
+        let color = color.into().to_linear().to_f32_array();
+        let base = self.buffer.pending.positions.len() as u32;
+        let mut rings = Vec::new();
+        for step in 1..=CAPSULE_HEMISPHERE_STEPS {
+            let angle = -FRAC_PI_2 + step as f32 * FRAC_PI_2 / CAPSULE_HEMISPHERE_STEPS as f32;
+            rings.push((
+                radius * angle.cos(),
+                -half_length + radius * angle.sin(),
+                angle.sin(),
+            ));
+        }
+        rings.push((radius, half_length, 0.0));
+        for step in 1..CAPSULE_HEMISPHERE_STEPS {
+            let angle = step as f32 * FRAC_PI_2 / CAPSULE_HEMISPHERE_STEPS as f32;
+            rings.push((
+                radius * angle.cos(),
+                half_length + radius * angle.sin(),
+                angle.sin(),
+            ));
+        }
+
+        let mut ring_indices = Vec::new();
+        let bottom_pole = self.push_capsule_vertex(
+            &mut ring_indices,
+            transform,
+            Vec3::NEG_Y,
+            -half_length,
+            radius,
+            color,
+        );
+        for &(ring_radius, y, normal_y) in &rings {
+            let mut ring = Vec::with_capacity(CAPSULE_SECTORS);
+            for sector in 0..CAPSULE_SECTORS {
+                let angle = sector as f32 * TAU / CAPSULE_SECTORS as f32;
+                let (sin, cos) = angle.sin_cos();
+                let normal = Vec3::new(
+                    cos * (1.0 - normal_y * normal_y).sqrt(),
+                    normal_y,
+                    sin * (1.0 - normal_y * normal_y).sqrt(),
+                );
+                ring.push(self.push_transformed_vertex(
+                    transform,
+                    Vec3::new(cos * ring_radius, y, sin * ring_radius),
+                    normal,
+                    color,
+                ));
+            }
+            ring_indices.push(ring);
+        }
+        let top_pole = self.push_capsule_vertex(
+            &mut ring_indices,
+            transform,
+            Vec3::Y,
+            half_length,
+            radius,
+            color,
+        );
+        for sector in 0..CAPSULE_SECTORS {
+            let next = (sector + 1) % CAPSULE_SECTORS;
+            self.buffer.pending.indices.extend([
+                bottom_pole,
+                ring_indices[0][next],
+                ring_indices[0][sector],
+            ]);
+            for ring in ring_indices.windows(2) {
+                self.buffer.pending.indices.extend([
+                    ring[0][sector],
+                    ring[0][next],
+                    ring[1][sector],
+                    ring[1][sector],
+                    ring[0][next],
+                    ring[1][next],
+                ]);
+            }
+            let last = ring_indices.len() - 1;
+            self.buffer.pending.indices.extend([
+                ring_indices[last][sector],
+                ring_indices[last][next],
+                top_pole,
+            ]);
+        }
+        // Keep the base used by this shape observable to avoid accidental
+        // future changes making the generated indices refer to another shape.
+        debug_assert!(base <= bottom_pole);
+    }
+
+    fn push_capsule_vertex(
+        &mut self,
+        _rings: &mut Vec<Vec<u32>>,
+        transform: Mat4,
+        normal: Vec3,
+        y: f32,
+        radius: f32,
+        color: [f32; 4],
+    ) -> u32 {
+        self.push_transformed_vertex(
+            transform,
+            Vec3::new(0.0, y + normal.y * radius, 0.0),
+            normal,
+            color,
+        )
+    }
+
+    fn push_transformed_vertex(
+        &mut self,
+        transform: Mat4,
+        position: Vec3,
+        normal: Vec3,
+        color: [f32; 4],
+    ) -> u32 {
+        let transformed_normal = transform
+            .inverse()
+            .transpose()
+            .transform_vector3(normal)
+            .normalize_or_zero();
+        let index = self.buffer.pending.positions.len() as u32;
+        self.push_vertex(
+            transform.transform_point3(position),
+            transformed_normal,
+            color,
+        );
+        index
+    }
+
+    fn push_vertex(&mut self, position: Vec3, normal: Vec3, color: [f32; 4]) {
+        self.buffer.pending.positions.push(position.to_array());
+        self.buffer.pending.normals.push(normal.to_array());
+        self.buffer.pending.colors.push(color);
+    }
+}
+
+pub struct FilledGizmosPlugin;
+
+const FILLED_GIZMO_SHADER_HANDLE: Handle<Shader> =
+    uuid_handle!("0e4a979f-ea11-4e5a-91cd-19c89d4e9b53");
+
+/// A deliberately minimal material: unlike `StandardMaterial`, its fragment
+/// shader writes vertex colors directly and therefore bypasses PBR lighting
+/// and camera tonemapping.
+#[derive(Asset, AsBindGroup, Reflect, Clone, Debug)]
+struct FilledGizmoMaterial {
+    #[uniform(0)]
+    color: LinearRgba,
+}
+
+impl Material for FilledGizmoMaterial {
+    fn vertex_shader() -> ShaderRef {
+        FILLED_GIZMO_SHADER_HANDLE.clone().into()
+    }
+
+    fn fragment_shader() -> ShaderRef {
+        FILLED_GIZMO_SHADER_HANDLE.clone().into()
+    }
+
+    fn alpha_mode(&self) -> AlphaMode {
+        AlphaMode::Blend
+    }
+
+    fn enable_prepass() -> bool {
+        false
+    }
+
+    fn enable_shadows() -> bool {
+        false
+    }
+
+    fn specialize(
+        _pipeline: &MaterialPipeline,
+        descriptor: &mut RenderPipelineDescriptor,
+        layout: &MeshVertexBufferLayoutRef,
+        _key: MaterialPipelineKey<Self>,
+    ) -> Result<(), SpecializedMeshPipelineError> {
+        descriptor.vertex.buffers = vec![layout.0.get_layout(&[
+            Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
+            Mesh::ATTRIBUTE_COLOR.at_shader_location(1),
+        ])?];
+        descriptor.primitive.cull_mode = None;
+        Ok(())
+    }
+}
+
+impl Plugin for FilledGizmosPlugin {
+    fn build(&self, app: &mut App) {
+        load_internal_asset!(
+            app,
+            FILLED_GIZMO_SHADER_HANDLE,
+            "filled_gizmo.wgsl",
+            Shader::from_wgsl
+        );
+        app.add_plugins(MaterialPlugin::<FilledGizmoMaterial>::default())
+            .init_resource::<FilledGizmoBuffer>()
+            .add_systems(Startup, setup_filled_gizmo_mesh)
+            .add_systems(FixedFirst, begin_fixed_filled_gizmos)
+            .add_systems(FixedLast, commit_fixed_filled_gizmos)
+            .add_systems(Last, upload_filled_gizmo_mesh);
+    }
+}
+
+fn setup_filled_gizmo_mesh(
+    mut commands: Commands,
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut materials: ResMut<Assets<FilledGizmoMaterial>>,
+    mut buffer: ResMut<FilledGizmoBuffer>,
+) {
+    let mesh = meshes.add(
+        Mesh::new(
+            PrimitiveTopology::TriangleList,
+            RenderAssetUsages::default(),
+        )
+        .with_inserted_attribute(Mesh::ATTRIBUTE_POSITION, vec![[0.0; 3]; 3])
+        .with_inserted_attribute(Mesh::ATTRIBUTE_NORMAL, vec![[0.0, 0.0, 1.0]; 3])
+        .with_inserted_attribute(Mesh::ATTRIBUTE_COLOR, vec![[0.0, 0.0, 0.0, 0.0]; 3])
+        .with_inserted_indices(Indices::U32(vec![0, 1, 2])),
+    );
+    let material = materials.add(FilledGizmoMaterial {
+        color: LinearRgba::WHITE,
+    });
+    commands.spawn((
+        Mesh3d(mesh.clone()),
+        MeshMaterial3d(material),
+        NoFrustumCulling,
+    ));
+    buffer.mesh = Some(mesh);
+}
+
+fn begin_fixed_filled_gizmos(mut buffer: ResMut<FilledGizmoBuffer>) {
+    buffer.pending = FilledGizmoGeometry::default();
+    buffer.fixed_commit = false;
+}
+
+fn commit_fixed_filled_gizmos(mut buffer: ResMut<FilledGizmoBuffer>) {
+    let pending = std::mem::take(&mut buffer.pending);
+    buffer.pending = std::mem::replace(&mut buffer.retained, pending);
+    buffer.fixed_commit = true;
+}
+
+fn upload_filled_gizmo_mesh(
+    mut meshes: ResMut<Assets<Mesh>>,
+    mut buffer: ResMut<FilledGizmoBuffer>,
+) {
+    // No fixed tick and no render-frame requests means the existing mesh is
+    // already the correct image. In particular, do not replace it with the
+    // empty placeholder between fixed updates.
+    if !buffer.fixed_commit && buffer.pending.positions.is_empty() {
+        return;
+    }
+    let Some(handle) = buffer.mesh.clone() else {
+        return;
+    };
+
+    let (positions, normals, colors, indices) = if buffer.fixed_commit {
+        // Retained geometry must remain in the CPU-side buffer after upload;
+        // otherwise the next render frame would have nothing to draw.
+        (
+            buffer.retained.positions.clone(),
+            buffer.retained.normals.clone(),
+            buffer.retained.colors.clone(),
+            buffer.retained.indices.clone(),
+        )
+    } else {
+        (
+            std::mem::take(&mut buffer.pending.positions),
+            std::mem::take(&mut buffer.pending.normals),
+            std::mem::take(&mut buffer.pending.colors),
+            std::mem::take(&mut buffer.pending.indices),
+        )
+    };
+
+    if let Some(mut mesh) = meshes.get_mut(&handle) {
+        if positions.is_empty() {
+            mesh.insert_attribute(Mesh::ATTRIBUTE_POSITION, vec![[0.0; 3]; 3]);
+            mesh.insert_attribute(Mesh::ATTRIBUTE_NORMAL, vec![[0.0, 0.0, 1.0]; 3]);
+            mesh.insert_attribute(Mesh::ATTRIBUTE_COLOR, vec![[0.0, 0.0, 0.0, 0.0]; 3]);
+            mesh.insert_indices(Indices::U32(vec![0, 1, 2]));
+        } else {
+            mesh.insert_attribute(Mesh::ATTRIBUTE_POSITION, positions);
+            mesh.insert_attribute(Mesh::ATTRIBUTE_NORMAL, normals);
+            mesh.insert_attribute(Mesh::ATTRIBUTE_COLOR, colors);
+            mesh.insert_indices(Indices::U32(indices));
+        }
+    }
+    buffer.pending = FilledGizmoGeometry::default();
+    buffer.fixed_commit = false;
+}

src/game_settings.rs

@@ -10,11 +10,15 @@ use crate::{math::int::FGi32, menus::style::FGUiStyle};
 pub struct FighterSettingsCommon {
     pub walk_speed_ease: FGi32,
 
+    /// Horizontal position nudge applied to each overlapping grounded fighter.
+    pub grounded_push_nudge: FGi32,
+
     /// Maximum allowed horizontal velocity
     pub ground_max_horizontal_velocity: FGi32,
 
     /// Ground friction applied when the fighter is above the walk speed
     pub ground_friction_over_walk_speed_multiplier: FGi32,
+    /// Minimum active launch frames between hits before airborne knockback stacks.
     pub knockback_stacking_window: u32,
     pub knockback_decay_per_frame: FGi32,
 
@@ -39,6 +43,32 @@ pub struct FighterSettingsCommon {
     
     /// Maximum angle changed caused by directional influence
     pub di_max_angle: FGi32,
+    pub leave_ground_ecb_frame_lock_duration: u32,
+    pub platform_pass_platform_ignore_duration_frames: u32,
+    pub platform_pass_initial_downwards_velocity: FGi32,
+    
+    pub intangible_color: Color,
+    pub intangible_pulse_duration: u32,
+    
+    pub angel_platform_invulnerability_duration: u32,
+    
+    /// Frames during which a fighter cannot grab any ledge after dropping from one.
+    pub ledge_drop_regrab_lockout_duration_frames: u32,
+    /// How many frames (+ the ledge animation duration) the fighter will be invulnerable after grabbing the ledge
+    pub ledge_grab_invulnerability_duration: u32,
+    /// How many times the fighter can grab the ledge without landing and still get invulnerability
+    pub max_ledge_grab_count: u32,
+
+    /// When hit while the receiver is in the air, use this angle
+    pub sakurai_angle_aerial_angle: FGi32,
+    /// When hit while the receiver is in the ground and at low knockback, use this angle
+    pub sakurai_angle_low_knockback_angle: FGi32,
+    /// When hit while the receiver is in the ground and at high knockback, use this angle
+    pub sakurai_angle_high_knockback_angle: FGi32,
+    /// past this threshold, the knockback is considered high, so it will use [sakurai_angle_high_knockback_angle]
+    pub sakurai_angle_knockback_threshold: FGi32,
+
+    pub waveland_snap_distance: FGi32,
 }
 #[derive(Reflect, Serialize, Deserialize, Clone)]
 #[reflect(opaque)]

src/input/frame.rs

@@ -2,13 +2,119 @@ use serde::{Deserialize, Serialize};
 
 use crate::math::vec::FGVec2;
 
+/// A fixed-width set of distinct bindings assigned to one logical action.
+/// Keeping binding identity in the rollback frame allows combinations such as
+/// pressing a second shield binding while the first one is still held.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, Serialize, Deserialize, Default)]
+pub struct ActionBindingMask(pub u16);
+
+impl ActionBindingMask {
+    pub const fn empty() -> Self {
+        Self(0)
+    }
+
+    pub const fn from_slot(slot: u8) -> Self {
+        Self(if slot < 16 { 1u16 << slot } else { 0 })
+    }
+
+    pub const fn contains(self, other: Self) -> bool {
+        self.0 & other.0 == other.0
+    }
+
+    pub const fn intersects(self, other: Self) -> bool {
+        self.0 & other.0 != 0
+    }
+
+    pub const fn count(self) -> u32 {
+        self.0.count_ones()
+    }
+
+    pub const fn pressed_since(self, previous: Self) -> Self {
+        Self(self.0 & !previous.0)
+    }
+
+    pub const fn released_since(self, previous: Self) -> Self {
+        Self(previous.0 & !self.0)
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, Serialize, Deserialize, Default)]
+pub struct DigitalActionBindings {
+    pub jump: ActionBindingMask,
+    pub shield: ActionBindingMask,
+    pub attack: ActionBindingMask,
+}
+
+impl DigitalActionBindings {
+    pub fn set(&mut self, action: DigitalAction, slot: u8, pressed: bool) {
+        let mask = match action {
+            DigitalAction::Jump => &mut self.jump,
+            DigitalAction::Shield => &mut self.shield,
+            DigitalAction::Attack => &mut self.attack,
+        };
+        let bit = ActionBindingMask::from_slot(slot).0;
+        if pressed {
+            mask.0 |= bit;
+        } else {
+            mask.0 &= !bit;
+        }
+    }
+
+    pub const fn get(self, action: DigitalAction) -> ActionBindingMask {
+        match action {
+            DigitalAction::Jump => self.jump,
+            DigitalAction::Shield => self.shield,
+            DigitalAction::Attack => self.attack,
+        }
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum DigitalAction {
+    Jump,
+    Shield,
+    Attack,
+}
+
 /// One frame of a player's raw input. This is the type GGRS serializes and
 /// sends over the wire, so keep it small and keep it `PartialEq`.
 #[derive(Copy, Clone, Debug, PartialEq, Default, Serialize, Deserialize, Hash)]
 pub struct FighterInputFrame {
     pub movement: FGVec2,
     pub directional_attack: FGVec2,
-    pub jump: bool,
+    pub bindings: DigitalActionBindings,
-    pub shield: bool,
+}
-    pub attack: bool,
+
+impl FighterInputFrame {
+    pub const fn bindings_for(self, action: DigitalAction) -> ActionBindingMask {
+        self.bindings.get(action)
+    }
+
+    pub const fn is_held(self, action: DigitalAction) -> bool {
+        self.bindings_for(action).0 != 0
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn binding_masks_preserve_distinct_same_action_bindings() {
+        let mut bindings = DigitalActionBindings::default();
+        bindings.set(DigitalAction::Shield, 0, true);
+        bindings.set(DigitalAction::Shield, 1, true);
+        assert_eq!(bindings.shield.0, 0b11);
+        assert_eq!(bindings.shield.count(), 2);
+        assert_eq!(bindings.shield.pressed_since(ActionBindingMask(1)).0, 0b10);
+    }
+
+    #[test]
+    fn clearing_one_binding_does_not_clear_the_other() {
+        let mut bindings = DigitalActionBindings::default();
+        bindings.set(DigitalAction::Shield, 0, true);
+        bindings.set(DigitalAction::Shield, 1, true);
+        bindings.set(DigitalAction::Shield, 0, false);
+        assert_eq!(bindings.shield.0, 0b10);
+    }
 }

src/input/gamecube/bridge.rs

@@ -7,7 +7,8 @@ use bevy::input::gamepad::{
 };
 use bevy::prelude::*;
 
-use super::poll::{GcAdapterSnapshot, GcPortState};
+use super::GcPorts;
+use super::poll::GcAdapterSnapshot;
 
 /// GameCube adapters report 4 ports.
 pub const GC_PORT_COUNT: usize = 4;
@@ -23,15 +24,6 @@ const GC_ADAPTER_PID: u16 = 0x0337;
 #[derive(Component, Debug, Clone, Copy)]
 pub struct GcPort(pub u8);
 
-/// Tracks which entity (if any) represents each of the 4 adapter ports,
-/// and the last snapshot seen, so both systems below can diff instead of
-/// re-deriving state every frame.
-#[derive(Resource, Default)]
-pub struct GcPorts {
-    pub entities: [Option<Entity>; GC_PORT_COUNT],
-    last: [GcPortState; GC_PORT_COUNT],
-}
-
 fn passthrough_gamepad_settings() -> GamepadSettings {
     let mut settings = GamepadSettings::default();
     for axis in GamepadAxis::all() {

src/input/gamecube/mod.rs

@@ -1,10 +1,23 @@
+#[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
 pub mod bridge;
+#[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
 pub mod poll;
 
-pub use bridge::{GC_PORT_COUNT, GcPort, GcPorts};
+#[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
+pub use bridge::{GC_PORT_COUNT, GcPort};
+#[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
 pub use poll::{GcAdapterSnapshot, GcPortState};
 
+#[derive(Resource, Default)]
+pub struct GcPorts {
+    pub entities: [Option<Entity>; 4],
+    #[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
+    pub(super) last: [poll::GcPortState; 4],
+}
+
+#[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
 use bevy::input::InputSystems;
+#[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
 use bevy::input::gamepad::{gamepad_connection_system, gamepad_event_processing_system};
 use bevy::prelude::*;
 
@@ -15,21 +28,24 @@ impl Plugin for GamecubeAdapterPlugin {
     fn build(&self, app: &mut App) {
         app.init_resource::<GcPorts>();
 
-        let Ok(snapshot) = poll::spawn_poll_thread() else {
+        #[cfg(all(feature = "gamecube-adapter", not(target_os = "windows")))]
-            // No adapter connected; leave GcPorts empty and skip wiring the
+        {
-            // polling systems.
+            let Ok(snapshot) = poll::spawn_poll_thread() else {
-            return;
+                // No adapter connected; leave GcPorts empty and skip wiring the
-        };
+                // polling systems.
+                return;
+            };
 
-        app.insert_resource(snapshot).add_systems(
+            app.insert_resource(snapshot).add_systems(
-            PreUpdate,
+                PreUpdate,
-            (
+                (
-                bridge::gc_connection_system.before(gamepad_connection_system),
+                    bridge::gc_connection_system.before(gamepad_connection_system),
-                bridge::gc_event_system
+                    bridge::gc_event_system
-                    .after(gamepad_connection_system)
+                        .after(gamepad_connection_system)
-                    .before(gamepad_event_processing_system),
+                        .before(gamepad_event_processing_system),
-            )
+                )
-                .in_set(InputSystems),
+                    .in_set(InputSystems),
-        );
+            );
+        }
     }
 }

src/input/gamecube/poll.rs

@@ -1,6 +1,8 @@
 use std::panic::{self, AssertUnwindSafe};
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::{Arc, Mutex};
+use std::thread::JoinHandle;
+use std::time::{Duration, Instant};
 
 use bevy::prelude::*;
 use gc_adapter_neo::{Controller, GcAdapter};
@@ -55,10 +57,11 @@ impl GcPortState {
 /// Shared, `Send + Sync` handle to the latest snapshot from the poll
 /// thread. Safe to store as an ordinary [`Resource`] (no `NonSend` needed)
 /// because the `GcAdapter` itself never leaves its thread.
-#[derive(Resource, Clone)]
+#[derive(Resource)]
 pub struct GcAdapterSnapshot {
     ports: Arc<Mutex<[GcPortState; 4]>>,
     shutdown: Arc<AtomicBool>,
+    poll_thread: Option<JoinHandle<()>>,
 }
 
 impl GcAdapterSnapshot {
@@ -69,14 +72,38 @@ impl GcAdapterSnapshot {
 
 impl Drop for GcAdapterSnapshot {
     fn drop(&mut self) {
-        // Only actually signals shutdown once the last clone (this resource
+        self.shutdown.store(true, Ordering::Release);
-        // is never cloned in practice, but be defensive) is dropped.
+
-        if Arc::strong_count(&self.shutdown) <= 1 {
+        if let Some(poll_thread) = self.poll_thread.take() {
-            self.shutdown.store(true, Ordering::Relaxed);
+            if let Err(payload) = poll_thread.join() {
+                error!(
+                    "GameCube Controller Adapter poll thread panicked during shutdown: {payload:?}"
+                );
+            }
         }
     }
 }
 
+const INITIAL_ERROR_BACKOFF: Duration = Duration::from_millis(1);
+const MAX_ERROR_BACKOFF: Duration = Duration::from_millis(100);
+
+fn next_error_backoff(backoff: Duration) -> Duration {
+    backoff.saturating_mul(2).min(MAX_ERROR_BACKOFF)
+}
+
+/// Wait for a retry while still allowing the owner to shut the poll thread down promptly.
+fn wait_for_retry(shutdown: &AtomicBool, delay: Duration) -> bool {
+    let deadline = Instant::now() + delay;
+    while !shutdown.load(Ordering::Acquire) {
+        let remaining = deadline.saturating_duration_since(Instant::now());
+        if remaining.is_zero() {
+            return true;
+        }
+        std::thread::sleep(remaining.min(Duration::from_millis(10)));
+    }
+    false
+}
+
 /// Connects to the first GameCube adapter found on the USB bus and starts
 /// polling it on a dedicated thread. Returns `None` (after logging a
 /// warning) if no adapter is plugged in
@@ -94,7 +121,7 @@ pub fn spawn_poll_thread() -> Result<GcAdapterSnapshot, gc_adapter_neo::UsbError
 
     let thread_ports = ports.clone();
     let thread_shutdown = shutdown.clone();
-    std::thread::Builder::new()
+    let poll_thread = std::thread::Builder::new()
         .name("gc-adapter-poll".into())
         .spawn(move || {
             // Flush whatever the adapter had buffered before we started
@@ -107,17 +134,27 @@ pub fn spawn_poll_thread() -> Result<GcAdapterSnapshot, gc_adapter_neo::UsbError
             let mut rate_window_start = std::time::Instant::now();
             #[cfg(debug_assertions)]
             let mut rate_window_count: u32 = 0;
+            let mut error_backoff = INITIAL_ERROR_BACKOFF;
 
-            while !thread_shutdown.load(Ordering::Relaxed) {
+            while !thread_shutdown.load(Ordering::Acquire) {
                 let result = panic::catch_unwind(AssertUnwindSafe(|| adapter.read_controllers()));
 
                 let controllers = match result {
-                    Ok(Ok(controllers)) => controllers,
+                    Ok(Ok(controllers)) => {
+                        error_backoff = INITIAL_ERROR_BACKOFF;
+                        controllers
+                    }
                     // Ignore this, for some reason we get a bunch of these when we start reading
                     Ok(Err(
                         gc_adapter_neo::AdapterError::Parse(_)
                         | gc_adapter_neo::AdapterError::ShortRead(_),
-                    )) => continue,
+                    )) => {
+                        if !wait_for_retry(&thread_shutdown, error_backoff) {
+                            break;
+                        }
+                        error_backoff = next_error_backoff(error_backoff);
+                        continue;
+                    }
                     Ok(Err(gc_adapter_neo::AdapterError::Usb(err))) => {
                         error!(
                             "GameCube Controller Adapter USB read failed ({err:?}); stopping \
@@ -160,5 +197,32 @@ pub fn spawn_poll_thread() -> Result<GcAdapterSnapshot, gc_adapter_neo::UsbError
         })
         .expect("failed to spawn gc-adapter poll thread");
 
-    Ok(GcAdapterSnapshot { ports, shutdown })
+    Ok(GcAdapterSnapshot {
+        ports,
+        shutdown,
+        poll_thread: Some(poll_thread),
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn error_backoff_is_capped() {
+        let mut backoff = INITIAL_ERROR_BACKOFF;
+        for _ in 0..16 {
+            backoff = next_error_backoff(backoff);
+        }
+
+        assert_eq!(backoff, MAX_ERROR_BACKOFF);
+        assert_eq!(next_error_backoff(MAX_ERROR_BACKOFF), MAX_ERROR_BACKOFF);
+    }
+
+    #[test]
+    fn retry_wait_stops_when_shutdown_is_requested() {
+        let shutdown = AtomicBool::new(true);
+
+        assert!(!wait_for_retry(&shutdown, Duration::from_secs(1)));
+    }
 }

src/input/gamepad.rs

@@ -9,15 +9,19 @@ use crate::math::vec::FGVec2;
 pub fn sample_gamepad(pad: &Gamepad, input_map: &BaseInputMap) -> FighterInputFrame {
     let mut input_frame = FighterInputFrame::default();
     let mut movement = Vec2::ZERO;
+    let mut directional_attack = Vec2::ZERO;
 
     for gamepad_element in &input_map.gamepad {
         match &gamepad_element.binding {
             GamepadBinding::Button(button) => {
                 let pressed = pad.pressed(*button);
+                if let Some(action) = gamepad_element.action.digital_action() {
+                    input_frame
+                        .bindings
+                        .set(action, gamepad_element.binding_slot, pressed);
+                }
                 match gamepad_element.action {
-                    InputMapAction::Jump => input_frame.jump |= pressed,
+                    InputMapAction::Jump | InputMapAction::Shield | InputMapAction::Attack => {}
-                    InputMapAction::Shield => input_frame.shield |= pressed,
-                    InputMapAction::Attack => input_frame.attack |= pressed,
                     // Digital buttons driving movement isn't used by the
                     // default bindings (the stick covers that), but stay
                     // consistent with the keyboard backend if one is added.
@@ -31,12 +35,24 @@ pub fn sample_gamepad(pad: &Gamepad, input_map: &BaseInputMap) -> FighterInputFr
                             movement.y += sign as f32
                         }
                     }
+                    InputMapAction::AttackXDir(sign) => {
+                        if pressed {
+                            directional_attack.x += sign as f32;
+                        }
+                    }
+                    InputMapAction::AttackYDir(sign) => {
+                        if pressed {
+                            directional_attack.y += sign as f32;
+                        }
+                    }
                 }
             }
             // gamepad does not have a separate axis for left and right, so sign here should be 1
             GamepadBinding::Axis(axis, sign) => {
                 let value = pad.get(*axis).unwrap_or(0.0) * (*sign as f32);
                 match gamepad_element.action {
+                    InputMapAction::AttackXDir(_) => directional_attack.x += value,
+                    InputMapAction::AttackYDir(_) => directional_attack.y += value,
                     InputMapAction::MovementXDir(_) => movement.x += value,
                     InputMapAction::MovementYDir(_) => movement.y += value,
                     _ => {}
@@ -46,6 +62,10 @@ pub fn sample_gamepad(pad: &Gamepad, input_map: &BaseInputMap) -> FighterInputFr
     }
 
     input_frame.movement = FGVec2::new(FGi32::from_num(movement.x), FGi32::from_num(movement.y));
+    input_frame.directional_attack = FGVec2::new(
+        FGi32::from_num(directional_attack.x),
+        FGi32::from_num(directional_attack.y),
+    );
 
     input_frame
 }

src/input/keyboard.rs

@@ -30,9 +30,21 @@ pub fn sample_keyboard(key: &ButtonInput<KeyCode>, input_map: &BaseInputMap) ->
             InputMapAction::MovementYDir(sign) => {
                 input_frame.movement.y += (sign) * action_strength
             }
-            InputMapAction::Jump => input_frame.jump = action_strength != FGi32::ZERO,
+            InputMapAction::Jump | InputMapAction::Shield | InputMapAction::Attack => {
-            InputMapAction::Shield => input_frame.shield = action_strength != FGi32::ZERO,
+                if let Some(action) = keyboard_elment.action.digital_action() {
-            InputMapAction::Attack => input_frame.attack = action_strength != FGi32::ZERO,
+                    input_frame.bindings.set(
+                        action,
+                        keyboard_elment.binding_slot,
+                        action_strength != FGi32::ZERO,
+                    );
+                }
+            }
+            InputMapAction::AttackXDir(sign) => {
+                input_frame.directional_attack.x += (sign) * action_strength;
+            }
+            InputMapAction::AttackYDir(sign) => {
+                input_frame.directional_attack.y += (sign) * action_strength;
+            }
         }
     }
 

src/input/map.rs

@@ -12,6 +12,8 @@ pub enum InputActionState {
 
 #[derive(Debug)]
 pub enum InputMapAction {
+    AttackXDir(i32),
+    AttackYDir(i32),
     MovementXDir(i32),
     MovementYDir(i32),
     Jump,
@@ -19,6 +21,18 @@ pub enum InputMapAction {
     Attack,
 }
 
+impl InputMapAction {
+    pub const fn digital_action(&self) -> Option<crate::input::DigitalAction> {
+        match self {
+            Self::Jump => Some(crate::input::DigitalAction::Jump),
+            Self::Shield => Some(crate::input::DigitalAction::Shield),
+            Self::Attack => Some(crate::input::DigitalAction::Attack),
+            Self::MovementXDir(_) | Self::MovementYDir(_) => None,
+            Self::AttackYDir(_) | Self::AttackXDir(_) => None,
+        }
+    }
+}
+
 #[derive(Debug)]
 pub enum MenuInputMapAction {
     MovementXDir(i32),
@@ -32,6 +46,7 @@ pub enum MenuInputMapAction {
 pub struct KeyboardInputMapElement {
     pub key: KeyCode,
     pub action: InputMapAction,
+    pub binding_slot: u8,
 }
 
 #[derive(Debug)]
@@ -44,6 +59,7 @@ pub enum GamepadBinding {
 pub struct GamepadInputMapElement {
     pub binding: GamepadBinding,
     pub action: InputMapAction,
+    pub binding_slot: u8,
 }
 
 #[derive(Debug)]

src/input/mod.rs

@@ -14,8 +14,8 @@ pub mod gamepad;
 pub mod keyboard;
 pub mod map;
 
-pub use buffer::{FighterCommands, FighterInput};
+pub use buffer::{FighterCommands, FighterInput, FlickDirection};
-pub use frame::FighterInputFrame;
+pub use frame::{ActionBindingMask, DigitalAction, DigitalActionBindings, FighterInputFrame};
 pub use map::{
     BaseInputMap, GamepadBinding, GamepadInputMapElement, InputActionState, InputMapAction,
     KeyboardInputMapElement, MenuGamepadInputMapElement, MenuInputMap, MenuInputMapAction,
@@ -28,7 +28,7 @@ pub enum LocalInputSource {
     Gamepad(Entity),
 }
 
-/// Maps an input source to a player index
+/// Persistent mapping from physical/menu controller slots to input sources.
 #[derive(Resource, Clone, Debug, Default, Deref, DerefMut)]
 pub struct LocalInputAssignments(pub Vec<(usize, LocalInputSource)>);
 
@@ -50,6 +50,16 @@ impl LocalInputAssignments {
     }
 }
 
+/// Match-local mapping from dense GGRS handles to physical input sources.
+#[derive(Resource, Clone, Debug, Default, Deref, DerefMut)]
+pub struct MatchInputAssignments(pub Vec<Option<LocalInputSource>>);
+
+impl MatchInputAssignments {
+    pub fn get_for_handle(&self, handle: usize) -> Option<LocalInputSource> {
+        self.0.get(handle).copied().flatten()
+    }
+}
+
 use crate::game_settings::GameSettings;
 use crate::math::int::FGi32;
 use crate::netcode::GGRSCfg;
@@ -68,36 +78,43 @@ impl Plugin for FighterInputPlugin {
                 KeyboardInputMapElement {
                     key: KeyCode::KeyD,
                     action: InputMapAction::MovementXDir(1),
+                    binding_slot: 0,
                 },
                 // left
                 KeyboardInputMapElement {
                     key: KeyCode::KeyA,
                     action: InputMapAction::MovementXDir(-1),
+                    binding_slot: 0,
                 },
                 // up
                 KeyboardInputMapElement {
                     key: KeyCode::KeyW,
                     action: InputMapAction::MovementYDir(1),
+                    binding_slot: 0,
                 },
                 // down
                 KeyboardInputMapElement {
                     key: KeyCode::KeyS,
                     action: InputMapAction::MovementYDir(-1),
+                    binding_slot: 0,
                 },
                 // jump
                 KeyboardInputMapElement {
                     key: KeyCode::Space,
                     action: InputMapAction::Jump,
+                    binding_slot: 0,
                 },
                 // shield/airdodge
                 KeyboardInputMapElement {
                     key: KeyCode::ShiftLeft,
                     action: InputMapAction::Shield,
+                    binding_slot: 0,
                 },
                 // attack
                 KeyboardInputMapElement {
                     key: KeyCode::KeyJ,
                     action: InputMapAction::Attack,
+                    binding_slot: 0,
                 },
                 // Menu
             ],
@@ -106,29 +123,50 @@ impl Plugin for FighterInputPlugin {
                 GamepadInputMapElement {
                     binding: GamepadBinding::Axis(GamepadAxis::LeftStickX, 1),
                     action: InputMapAction::MovementXDir(1),
+                    binding_slot: 0,
                 },
                 GamepadInputMapElement {
                     binding: GamepadBinding::Axis(GamepadAxis::LeftStickY, 1),
                     action: InputMapAction::MovementYDir(1),
+                    binding_slot: 0,
                 },
                 // jump
                 GamepadInputMapElement {
                     binding: GamepadBinding::Button(GamepadButton::North),
                     action: InputMapAction::Jump,
-                },
+                    binding_slot: 0,
-                // shield/airdodge -- both shoulder buttons, Melee-style
-                GamepadInputMapElement {
-                    binding: GamepadBinding::Button(GamepadButton::LeftTrigger),
-                    action: InputMapAction::Shield,
                 },
                 GamepadInputMapElement {
-                    binding: GamepadBinding::Button(GamepadButton::RightTrigger),
+                    binding: GamepadBinding::Button(GamepadButton::West),
+                    action: InputMapAction::Jump,
+                    binding_slot: 1,
+                },
+                GamepadInputMapElement {
+                    binding: GamepadBinding::Button(GamepadButton::LeftTrigger2),
                     action: InputMapAction::Shield,
+                    binding_slot: 0,
+                },
+                GamepadInputMapElement {
+                    binding: GamepadBinding::Button(GamepadButton::RightTrigger2),
+                    action: InputMapAction::Shield,
+                    binding_slot: 1,
                 },
                 // attack
                 GamepadInputMapElement {
                     binding: GamepadBinding::Button(GamepadButton::East),
                     action: InputMapAction::Attack,
+                    binding_slot: 0,
+                },
+                //C-stick
+                GamepadInputMapElement {
+                    binding: GamepadBinding::Axis(GamepadAxis::RightStickX, 1),
+                    action: InputMapAction::AttackXDir(1),
+                    binding_slot: 0,
+                },
+                GamepadInputMapElement {
+                    binding: GamepadBinding::Axis(GamepadAxis::RightStickY, 1),
+                    action: InputMapAction::AttackYDir(1),
+                    binding_slot: 0,
                 },
             ],
         })
@@ -237,6 +275,13 @@ fn preprocess_input_frame(frame: &mut FighterInputFrame, game_settings: &GameSet
     if frame.movement.y.abs() < game_settings.input_common.stick_deadzone {
         frame.movement.y = FGi32::ZERO;
     }
+
+    if frame.directional_attack.x.abs() < game_settings.input_common.stick_deadzone {
+        frame.directional_attack.x = FGi32::ZERO;
+    }
+    if frame.directional_attack.y.abs() < game_settings.input_common.stick_deadzone {
+        frame.directional_attack.y = FGi32::ZERO;
+    }
 }
 
 fn read_local_inputs(
@@ -245,20 +290,17 @@ fn read_local_inputs(
     input_map: Res<BaseInputMap>,
     gc_ports: Res<gamecube::GcPorts>,
     gamepads: Query<&Gamepad>,
-    assignments: Res<LocalInputAssignments>,
+    assignments: Res<MatchInputAssignments>,
     local_players: Res<LocalPlayers>,
     game_settings: Res<GameSettings>,
 ) {
     let mut local_inputs = HashMap::new();
 
     for handle in &local_players.0 {
-        let assigned = assignments
+        let assigned = assignments.get_for_handle(*handle);
-            .0
-            .iter()
-            .find(|(player_handle, _)| player_handle == handle);
         let gamepad = match assigned {
-            Some((_, LocalInputSource::Gamepad(entity))) => gamepads.get(*entity).ok(),
+            Some(LocalInputSource::Gamepad(entity)) => gamepads.get(entity).ok(),
-            Some((_, LocalInputSource::Keyboard)) => None,
+            Some(LocalInputSource::Keyboard) => None,
             None => gc_ports
                 .entities
                 .get(*handle)
@@ -268,8 +310,8 @@ fn read_local_inputs(
         };
 
         let mut input_frame = match assigned {
-            Some((_, LocalInputSource::Keyboard)) => keyboard::sample_keyboard(&key, &input_map),
+            Some(LocalInputSource::Keyboard) => keyboard::sample_keyboard(&key, &input_map),
-            Some((_, LocalInputSource::Gamepad(_))) => gamepad
+            Some(LocalInputSource::Gamepad(_)) => gamepad
                 .map(|pad| gamepad::sample_gamepad(pad, &input_map))
                 .unwrap_or_default(),
             None => FighterInputFrame::default(),

src/lib.rs

@@ -21,6 +21,8 @@
 //! save, click Rebuild in jackdaw (or run `jd build`) and it
 //! appears in `Add Component`. No registration code is needed.
 
+#![recursion_limit = "512"]
+
 use bevy::{
     asset::processor::{AssetProcessor, ProcessorState},
     prelude::*,
@@ -33,8 +35,9 @@ use ron_asset_manager::RonAssetPlugin;
 
 use crate::{
     camera::MatchCameraPlugin, fighter::manifest::FighterManifest, game_settings::GameSettings,
-    match_runtime::MatchRuntimePlugin, menus::style::FGUiStyle, schedule::GameplaySchedulePlugin,
+    match_runtime::MatchRuntimePlugin, materials::ShinesparkMaterialPlugin,
-    stage::manifest::StageManifest, ui::InGameUIPlugin,
+    menus::style::FGUiStyle, schedule::GameplaySchedulePlugin, stage::manifest::StageManifest,
+    ui::InGameUIPlugin,
 };
 
 mod args;
@@ -42,10 +45,14 @@ pub mod blend_asset;
 pub mod camera;
 pub mod debug_tools;
 pub mod fighter;
+pub mod filled_gizmos;
 pub mod game_settings;
 pub mod input;
+#[cfg(feature = "hitbox-viewer")]
+pub mod hitbox_viewer;
 pub mod match_loading;
 pub mod match_runtime;
+pub mod materials;
 mod math;
 pub mod menus;
 pub mod netcode;
@@ -56,6 +63,7 @@ pub mod scripting;
 pub mod stage;
 pub mod texture_reference;
 pub mod ui;
+pub mod egui_color_convert;
 
 #[derive(States, Debug, Clone, Copy, Eq, PartialEq, Hash, Default)]
 pub enum AppState {
@@ -74,6 +82,7 @@ pub enum AppState {
     LoadingMatch,
     PreparingMatch,
     InMatch,
+    MatchResults,
     MatchDisconnected,
     MatchLoadFailed,
 }
@@ -106,21 +115,25 @@ impl Plugin for GamePlugin {
         // game-level content and configuration.
         app.init_state::<AppState>()
             .add_plugins((
-                SettingsPlugin::new("moe.eirteam.shinespark.debug_settings"),
+                (
-                // Brings up GGRS (and with it `GgrsSchedule`), so it goes first.
+                    SettingsPlugin::new("moe.eirteam.shinespark.debug_settings"),
-                netcode::FighterNetcodePlugin::default(),
+                    // Brings up GGRS (and with it `GgrsSchedule`), so it goes first.
-                GameplaySchedulePlugin,
+                    netcode::FighterNetcodePlugin::default(),
-                MatchRuntimePlugin,
+                    GameplaySchedulePlugin,
-                input::FighterInputPlugin,
+                    MatchRuntimePlugin,
-                replay::ReplayPlugin,
+                    input::FighterInputPlugin,
-                debug_tools::DebugToolsPlugin,
+                    replay::ReplayPlugin,
-                fighter::FighterPlugin,
+                    debug_tools::DebugToolsPlugin,
-                fighter::baked_animation::BakedAnimationPlugin,
+                    filled_gizmos::FilledGizmosPlugin,
-                scripting::importer::FighterScriptImportPlugin,
+                    fighter::FighterPlugin,
-                stage::StagePlugin,
+                    fighter::baked_animation::BakedAnimationPlugin,
-                MatchCameraPlugin,
+                    scripting::importer::FighterScriptImportPlugin,
-                GameAssetPlugin,
+                    stage::StagePlugin,
-                InGameUIPlugin,
+                    MatchCameraPlugin,
+                    GameAssetPlugin,
+                    InGameUIPlugin,
+                ),
+                ShinesparkMaterialPlugin,
             ))
             .add_plugins(menus::MenuPlugin)
             .add_loading_state(

src/match_loading.rs

@@ -8,9 +8,7 @@ use bevy_ggrs::prelude::Session;
 use serde::{Deserialize, Serialize};
 
 use crate::{
-    AppState,
+    AppState, args::Args, fighter::{
-    args::Args,
-    fighter::{
         FighterId, FighterRoster,
         animation::AnimKind,
         attack::{AttackKind, FighterAttackScriptAssets},
@@ -18,16 +16,10 @@ use crate::{
         manifest::{FighterManifest, FighterManifestRegistry},
         spawn_fighter,
         visual::FighterAnimations,
-    },
+    }, input::{LocalInputAssignments, LocalInputSource, MatchInputAssignments}, match_runtime::MatchState, netcode::{
-    input::{LocalInputAssignments, LocalInputSource},
-    match_runtime::MatchState,
-    math::{int::FGi32, vec::FGVec2},
-    netcode::{
         GGRSCfg,
         session::{ConnectionStatus, SessionConfig, create_session},
-    },
+    }, scripting::FighterAttackScript, stage::{
-    scripting::FighterAttackScript,
-    stage::{
         self,
         manifest::{StageId, StageManifest, StageManifestRegistry},
     },
@@ -35,7 +27,10 @@ use crate::{
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
 pub struct MatchPlayer {
+    /// Dense index used by GGRS and rollback-simulated player state.
     pub handle: usize,
+    /// Physical controller port selected in the menu.
+    pub controller_port: usize,
     pub fighter: FighterId,
 }
 
@@ -46,6 +41,22 @@ pub struct MatchConfig {
     pub rules: MatchRules,
 }
 
+impl MatchConfig {
+    /// Maps a GGRS handle to the controller port used by gameplay.
+    ///
+    /// Multiplayer uses the stable, dense GGRS handle as the port. A
+    /// single-player match preserves the physical controller port selected in
+    /// the menu (for example, port 3 remains port 3).
+    pub fn controller_port_for_handle(&self, handle: usize) -> Option<usize> {
+        let player = self.players.iter().find(|player| player.handle == handle)?;
+        Some(if self.players.len() > 1 {
+            handle
+        } else {
+            player.controller_port
+        })
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub enum MatchRules {
     Stock {
@@ -228,6 +239,7 @@ pub fn initiate_default_match(
     let players = (0..args.players)
         .map(|handle| MatchPlayer {
             handle,
+            controller_port: handle,
             fighter: FighterId::TestFighter,
         })
         .collect();
@@ -263,6 +275,7 @@ pub fn initiate_default_match(
 pub fn prepare_match(
     mut commands: Commands,
     config: Res<MatchConfig>,
+    input_assignments: Res<LocalInputAssignments>,
     assets: Res<MatchAssets>,
     gltfs: Res<Assets<Gltf>>,
     baked_animations: Res<Assets<BakedFighterAnimations>>,
@@ -277,7 +290,7 @@ pub fn prepare_match(
     if !valid_player_handles(&config.players) {
         fail_match(
             &mut next_state,
-            "player handles must be unique and cover 0..player_count",
+            "player handles must be dense, unique, and non-empty",
         );
         return;
     }
@@ -287,6 +300,20 @@ pub fn prepare_match(
         return;
     }
 
+    let stage_handle = stage_registry
+        .get(config.stage)
+        .expect("Initialization check should ensure all stages exist");
+    let stage_manifest = stage_manifests
+        .get(&stage_handle)
+        .expect("Initialization check should ensure stage manifests are kept alive");
+    let spawn_positions = match stage_manifest.neutral_spawn_positions(config.players.len()) {
+        Ok(positions) => positions,
+        Err(error) => {
+            fail_match(&mut next_state, &error);
+            return;
+        }
+    };
+
     if assets.fighters.len() != config.players.len() {
         fail_match(
             &mut next_state,
@@ -336,6 +363,25 @@ pub fn prepare_match(
             );
             return;
         }
+        if !baked.contains_bone(&manifest.root_motion_bone) {
+            fail_match(
+                &mut next_state,
+                &format!(
+                    "{:?} references missing root motion bone {:?}",
+                    character.fighter, manifest.root_motion_bone
+                ),
+            );
+            return;
+        }
+
+        let ecb_bone_indices = baked.bone_names.iter().enumerate().filter_map(|(idx, name)| {
+            if manifest.ecb_bones.contains(name) {
+                Some(idx)
+            } else {
+                None
+            }
+        }).collect::<Vec<_>>();
+
         if let Err(error) = manifest.attributes.validate() {
             fail_match(
                 &mut next_state,
@@ -436,10 +482,12 @@ pub fn prepare_match(
             attack_scripts,
             manifest_handle,
             manifest.model_scale,
+            ecb_bone_indices,
         ));
     }
 
-    let session_config = match SessionConfig::from_args(&args, config.players.len()) {
+    let session_player_count = player_count_for_handles(&config.players);
+    let session_config = match SessionConfig::from_args(&args, session_player_count) {
         Ok(config) => config,
         Err(error) => {
             fail_match(
@@ -449,7 +497,7 @@ pub fn prepare_match(
             return;
         }
     };
-    let session = match create_session(&args, config.players.len()) {
+    let session = match create_session(&args, session_player_count) {
         Ok(session) => session,
         Err(error) => {
             fail_match(
@@ -460,14 +508,13 @@ pub fn prepare_match(
         }
     };
 
+    commands.insert_resource(create_match_input_assignments(
+        &input_assignments,
+        &config.players,
+    ));
+
     let root = commands.spawn((Name::new("Match"), MatchRoot)).id();
 
-    let stage_handle = stage_registry
-        .get(config.stage)
-        .expect("Initialization check should ensure all stages exist");
-    let stage_manifest = stage_manifests
-        .get(&stage_handle)
-        .expect("Initialization check should ensure stage manifests are kept alive");
     stage::spawn_stage(
         &mut commands,
         root,
@@ -477,19 +524,24 @@ pub fn prepare_match(
     );
 
     let mut fighter_roster = Vec::with_capacity(config.players.len());
-    for (index, (player, (scene, animations, attack_scripts, manifest_handle, model_scale))) in
+
+    for (spawn_index, (player, (scene, animations, attack_scripts, manifest_handle, model_scale, ecb_bone_indices))) in
         config.players.iter().zip(prepared).enumerate()
     {
-        let spawn_x = (index as i32 * 2 + 1 - config.players.len() as i32) * 5;
+        let spawn_point = spawn_positions[spawn_index];
         fighter_roster.push(spawn_fighter(
             &mut commands,
             player.handle,
-            FGVec2::new(FGi32::from_num(spawn_x), FGi32::lit("12.5")),
+            config
+                .controller_port_for_handle(player.handle)
+                .expect("validated match config contains every player handle"),
+            spawn_point,
             manifest_handle.clone(),
             model_scale,
             animations,
             attack_scripts,
             WorldAssetRoot(scene),
+            ecb_bone_indices
         ));
     }
 
@@ -507,12 +559,30 @@ fn fail_match(next_state: &mut NextState<AppState>, message: &str) {
 }
 
 fn valid_player_handles(players: &[MatchPlayer]) -> bool {
-    let mut handles = players
+    if players.is_empty() {
-        .iter()
+        return false;
-        .map(|player| player.handle)
+    }
-        .collect::<Vec<_>>();
+
+    let mut handles = players.iter().map(|player| player.handle).collect::<Vec<_>>();
     handles.sort_unstable();
-    handles == (0..players.len()).collect::<Vec<_>>()
+    handles.into_iter().eq(0..players.len())
+}
+
+fn player_count_for_handles(players: &[MatchPlayer]) -> usize {
+    players.len()
+}
+
+fn create_match_input_assignments(
+    assignments: &LocalInputAssignments,
+    players: &[MatchPlayer],
+) -> MatchInputAssignments {
+    let mut match_assignments = vec![None; players.len()];
+    for player in players {
+        match_assignments[player.handle] = assignments
+            .get_from_slot(player.controller_port)
+            .copied();
+    }
+    MatchInputAssignments(match_assignments)
 }
 
 pub fn cleanup_match(
@@ -533,6 +603,7 @@ pub fn cleanup_match(
     commands.remove_resource::<MatchAssets>();
     commands.remove_resource::<MatchConfig>();
     commands.remove_resource::<MatchState>();
+    commands.remove_resource::<MatchInputAssignments>();
     commands.remove_resource::<FighterRoster>();
 }
 
@@ -547,10 +618,12 @@ mod tests {
             players: vec![
                 MatchPlayer {
                     handle: 0,
+                    controller_port: 0,
                     fighter: FighterId::TestFighter,
                 },
                 MatchPlayer {
                     handle: 1,
+                    controller_port: 1,
                     fighter: FighterId::TestFighter,
                 },
             ],
@@ -568,10 +641,12 @@ mod tests {
         let players = [
             MatchPlayer {
                 handle: 0,
+                controller_port: 0,
                 fighter: FighterId::TestFighter,
             },
             MatchPlayer {
                 handle: 0,
+                controller_port: 1,
                 fighter: FighterId::TestFighter,
             },
         ];
@@ -579,6 +654,88 @@ mod tests {
         assert!(!valid_player_handles(&players));
     }
 
+    #[test]
+    fn player_handles_must_not_have_gaps() {
+        let players = [
+            MatchPlayer {
+                handle: 0,
+                controller_port: 0,
+                fighter: FighterId::TestFighter,
+            },
+            MatchPlayer {
+                handle: 2,
+                controller_port: 3,
+                fighter: FighterId::TestFighter,
+            },
+        ];
+
+        assert!(!valid_player_handles(&players));
+        assert_eq!(player_count_for_handles(&players), 2);
+    }
+
+    #[test]
+    fn controller_ports_use_ggrs_handles_only_in_multiplayer() {
+        let single_player = MatchConfig {
+            stage: StageId::TestStage,
+            players: vec![MatchPlayer {
+                handle: 0,
+                controller_port: 3,
+                fighter: FighterId::TestFighter,
+            }],
+            rules: MatchRules::default(),
+        };
+        assert_eq!(single_player.controller_port_for_handle(0), Some(3));
+
+        let multiplayer = MatchConfig {
+            stage: StageId::TestStage,
+            players: vec![
+                MatchPlayer {
+                    handle: 0,
+                    controller_port: 0,
+                    fighter: FighterId::TestFighter,
+                },
+                MatchPlayer {
+                    handle: 1,
+                    controller_port: 3,
+                    fighter: FighterId::TestFighter,
+                },
+            ],
+            rules: MatchRules::default(),
+        };
+        assert_eq!(multiplayer.controller_port_for_handle(0), Some(0));
+        assert_eq!(multiplayer.controller_port_for_handle(1), Some(1));
+    }
+
+    #[test]
+    fn match_input_assignments_map_ports_to_ggrs_handles_without_mutating_ports() {
+        let players = [
+            MatchPlayer {
+                handle: 0,
+                controller_port: 0,
+                fighter: FighterId::TestFighter,
+            },
+            MatchPlayer {
+                handle: 1,
+                controller_port: 3,
+                fighter: FighterId::TestFighter,
+            },
+        ];
+        let assignments = LocalInputAssignments(vec![
+            (0, LocalInputSource::Keyboard),
+            (3, LocalInputSource::Gamepad(Entity::PLACEHOLDER)),
+        ]);
+
+        let match_assignments = create_match_input_assignments(&assignments, &players);
+
+        assert_eq!(match_assignments.get_for_handle(0), Some(LocalInputSource::Keyboard));
+        assert_eq!(
+            match_assignments.get_for_handle(1),
+            Some(LocalInputSource::Gamepad(Entity::PLACEHOLDER))
+        );
+        assert_eq!(assignments[0].0, 0);
+        assert_eq!(assignments[1].0, 3);
+    }
+
     #[test]
     fn match_rules_reject_zero_limits() {
         assert!(

src/match_runtime.rs

@@ -1,15 +1,22 @@
 //! Rollback-simulated state for an active match.
 
+use bevy::input::InputSystems;
 use bevy::prelude::*;
-use bevy_ggrs::prelude::*;
+use bevy_ggrs::{ConfirmedFrameCount, RollbackFrameCount, RunGgrsSystems, prelude::*};
 
-use crate::match_loading::{MatchConfig, MatchRules};
+use crate::{
+    AppState,
+    match_loading::{MatchConfig, MatchRules},
+    netcode::session::SessionConfig,
+};
 
 #[derive(Resource, Clone, Debug, Hash, PartialEq, Eq)]
 pub struct MatchState {
     pub elapsed_frames: u32,
     /// Indexed by the player's session handle.
     pub players: Vec<PlayerMatchState>,
+    /// The rollback frame on which the match first finished.
+    pub finished_at_frame: Option<i32>,
 }
 
 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
@@ -19,6 +26,11 @@ pub struct PlayerMatchState {
     pub deaths: u32,
 }
 
+#[derive(Resource, Debug, Default, Clone, Copy, PartialEq, Eq)]
+pub struct PauseState {
+    pub paused: bool,
+}
+
 impl MatchState {
     pub fn from_config(config: &MatchConfig) -> Self {
         let stocks_remaining = match &config.rules {
@@ -37,8 +49,66 @@ impl MatchState {
                     deaths: 0,
                 })
                 .collect(),
+            finished_at_frame: None,
         }
     }
+
+    pub fn is_match_finished(&self, config: &MatchConfig) -> bool {
+        let time_limit = match config.rules {
+            MatchRules::Stock {
+                starting_stocks: _,
+                time_limit_frames,
+            } => time_limit_frames,
+            MatchRules::Timed { time_limit_frames } => Some(time_limit_frames),
+        };
+
+        if let Some(time_limit) = time_limit {
+            if self.elapsed_frames >= time_limit {
+                return true;
+            }
+        }
+
+        if config.players.len() > 1
+            && let MatchRules::Stock {
+                starting_stocks: _,
+                time_limit_frames: _,
+            } = config.rules
+        {
+            let alive_fighter_count = self
+                .players
+                .iter()
+                .filter(|fighter| {
+                    fighter
+                        .stocks_remaining
+                        .map(|stocks| stocks)
+                        .unwrap_or_default()
+                        > 0
+                })
+                .count();
+            if alive_fighter_count <= 1 {
+                return true;
+            }
+        }
+
+        false
+    }
+
+    fn advance_frame(&mut self, config: &MatchConfig, frame: i32) {
+        if self.finished_at_frame.is_some() {
+            return;
+        }
+
+        self.elapsed_frames = self.elapsed_frames.saturating_add(1);
+
+        if self.is_match_finished(config) {
+            self.finished_at_frame = Some(frame);
+        }
+    }
+
+    fn finish_is_confirmed(&self, confirmed_frame: i32) -> bool {
+        self.finished_at_frame
+            .is_some_and(|finished_at| confirmed_frame >= finished_at)
+    }
 }
 
 pub struct MatchRuntimePlugin;
@@ -46,7 +116,80 @@ pub struct MatchRuntimePlugin;
 impl Plugin for MatchRuntimePlugin {
     fn build(&self, app: &mut App) {
         app.rollback_resource_with_clone::<MatchState>()
-            .checksum_resource_with_hash::<MatchState>();
+            .checksum_resource_with_hash::<MatchState>()
+            .init_resource::<PauseState>()
+            .configure_sets(PreUpdate, RunGgrsSystems.run_if(ggrs_should_run))
+            .add_systems(OnEnter(AppState::InMatch), reset_pause)
+            .add_systems(OnExit(AppState::InMatch), reset_pause)
+            .add_systems(
+                GgrsSchedule,
+                update_match_rules.in_set(crate::schedule::GameplaySet::MatchRules),
+            )
+            .add_systems(
+                PreUpdate,
+                toggle_pause
+                    .after(InputSystems)
+                    .before(RunGgrsSystems)
+                    .run_if(in_state(AppState::InMatch)),
+            )
+            .add_systems(
+                Update,
+                transition_after_confirmed_finish.run_if(in_state(AppState::InMatch)),
+            );
+    }
+}
+
+pub fn ggrs_should_run(pause: Option<Res<PauseState>>) -> bool {
+    !pause.is_some_and(|pause| pause.paused)
+}
+
+pub(crate) fn match_is_ongoing(match_state: Option<Res<MatchState>>) -> bool {
+    match_state.is_none_or(|match_state| match_state.finished_at_frame.is_none())
+}
+
+fn toggle_pause(
+    key: Res<ButtonInput<KeyCode>>,
+    gamepads: Query<&Gamepad>,
+    session: Res<SessionConfig>,
+    mut pause: ResMut<PauseState>,
+    mut virtual_time: ResMut<Time<Virtual>>,
+) {
+    if session.is_multiplayer() {
+        return;
+    }
+
+    let pressed = key.just_pressed(KeyCode::Escape)
+        || gamepads
+            .iter()
+            .any(|gamepad| gamepad.just_pressed(GamepadButton::Start));
+    if !pressed {
+        return;
+    }
+
+    pause.paused = !pause.paused;
+    virtual_time.toggle();
+}
+
+fn reset_pause(mut pause: ResMut<PauseState>, mut virtual_time: ResMut<Time<Virtual>>) {
+    pause.paused = false;
+    virtual_time.unpause();
+}
+
+fn update_match_rules(
+    mut match_state: ResMut<MatchState>,
+    match_config: Res<MatchConfig>,
+    frame: Res<RollbackFrameCount>,
+) {
+    match_state.advance_frame(&match_config, frame.0);
+}
+
+fn transition_after_confirmed_finish(
+    match_state: Res<MatchState>,
+    confirmed_frame: Res<ConfirmedFrameCount>,
+    mut next_state: ResMut<NextState<AppState>>,
+) {
+    if match_state.finish_is_confirmed(confirmed_frame.0) {
+        next_state.set(AppState::MatchResults);
     }
 }
 
@@ -61,10 +204,12 @@ mod tests {
             players: vec![
                 MatchPlayer {
                     handle: 1,
+                    controller_port: 3,
                     fighter: FighterId::TestFighter,
                 },
                 MatchPlayer {
                     handle: 0,
+                    controller_port: 0,
                     fighter: FighterId::TestFighter,
                 },
             ],
@@ -80,6 +225,7 @@ mod tests {
         }));
 
         assert_eq!(state.elapsed_frames, 0);
+        assert_eq!(state.finished_at_frame, None);
         assert_eq!(state.players.len(), 2);
         assert!(state.players.iter().all(|player| {
             player.stocks_remaining == Some(4) && player.score == 0 && player.deaths == 0
@@ -99,4 +245,74 @@ mod tests {
                 .all(|player| player.stocks_remaining.is_none())
         );
     }
+
+    #[test]
+    fn timed_match_finishes_on_its_rollback_frame() {
+        let config = config(MatchRules::Timed {
+            time_limit_frames: 2,
+        });
+        let mut state = MatchState::from_config(&config);
+
+        state.advance_frame(&config, 10);
+        assert_eq!(state.elapsed_frames, 1);
+        assert_eq!(state.finished_at_frame, None);
+
+        state.advance_frame(&config, 11);
+        assert_eq!(state.elapsed_frames, 2);
+        assert_eq!(state.finished_at_frame, Some(11));
+        assert!(!state.finish_is_confirmed(10));
+        assert!(state.finish_is_confirmed(11));
+
+        state.advance_frame(&config, 12);
+        assert_eq!(state.finished_at_frame, Some(11));
+        assert_eq!(state.elapsed_frames, 2);
+    }
+
+    #[test]
+    fn corrected_rollback_state_does_not_keep_speculative_finish() {
+        let config = config(MatchRules::Stock {
+            starting_stocks: 1,
+            time_limit_frames: None,
+        });
+        let state_before_prediction = MatchState::from_config(&config);
+        let mut predicted_state = state_before_prediction.clone();
+        predicted_state.players[1].stocks_remaining = Some(0);
+        predicted_state.advance_frame(&config, 20);
+        assert_eq!(predicted_state.finished_at_frame, Some(20));
+
+        let mut corrected_state = state_before_prediction;
+        corrected_state.advance_frame(&config, 20);
+        assert_eq!(corrected_state.finished_at_frame, None);
+        assert!(!corrected_state.finish_is_confirmed(20));
+    }
+
+    #[test]
+    fn single_player_stock_match_does_not_finish_by_elimination() {
+        let mut config = config(MatchRules::Stock {
+            starting_stocks: 1,
+            time_limit_frames: None,
+        });
+        config.players.truncate(1);
+        let mut state = MatchState::from_config(&config);
+
+        state.advance_frame(&config, 1);
+        assert_eq!(state.finished_at_frame, None);
+
+        state.players[0].stocks_remaining = Some(0);
+        state.advance_frame(&config, 2);
+        assert_eq!(state.finished_at_frame, None);
+    }
+
+    #[test]
+    fn single_player_stock_match_can_finish_by_time_limit() {
+        let mut config = config(MatchRules::Stock {
+            starting_stocks: 1,
+            time_limit_frames: Some(1),
+        });
+        config.players.truncate(1);
+        let mut state = MatchState::from_config(&config);
+
+        state.advance_frame(&config, 7);
+        assert_eq!(state.finished_at_frame, Some(7));
+    }
 }

src/materials/fighter_material.rs

@@ -0,0 +1,92 @@
+use bevy::{
+    gltf::GltfMaterialName,
+    pbr::{ExtendedMaterial, MaterialExtension},
+    prelude::*,
+    render::render_resource::AsBindGroup,
+    shader::ShaderRef,
+    world_serialization::WorldInstanceReady,
+};
+
+pub type FighterMaterial = ExtendedMaterial<StandardMaterial, FighterMaterialExtension>;
+
+#[derive(Component)]
+pub struct FighterMesh {
+    pub fighter: Entity,
+}
+
+#[derive(Asset, AsBindGroup, Reflect, Debug, Clone, Default)]
+pub struct FighterMaterialExtension {
+    #[uniform(100)]
+    status_color: LinearRgba,
+    #[uniform(100)]
+    status_color_intensity: f32,
+}
+
+const SHADER_ASSET_PATH: &str = "embedded://shinespark/shaders/fighter.wgsl";
+
+impl FighterMaterialExtension {
+    pub fn new(status_color: Color) -> Self {
+        Self {
+            status_color: status_color.into(),
+            status_color_intensity: 0.0,
+            ..default()
+        }
+    }
+
+    pub fn update_status_color(&mut self, status_color: LinearRgba, intensity: f32) {
+        self.status_color = status_color;
+        self.status_color_intensity = intensity;
+    }
+}
+
+impl MaterialExtension for FighterMaterialExtension {
+    fn fragment_shader() -> ShaderRef {
+        SHADER_ASSET_PATH.into()
+    }
+
+    fn deferred_fragment_shader() -> ShaderRef {
+        SHADER_ASSET_PATH.into()
+    }
+}
+
+pub fn bind_fighter_material(
+    scene_ready: On<WorldInstanceReady>,
+    mut commands: Commands,
+    children: Query<&Children>,
+    //color_override: Query<&ColorOverride>,
+    mesh_materials: Query<(Entity, &MeshMaterial3d<StandardMaterial>, &GltfMaterialName)>,
+    mut asset_materials: ResMut<Assets<FighterMaterial>>,
+    original_materials: Res<Assets<StandardMaterial>>,
+) {
+    for descendant in children.iter_descendants(scene_ready.entity) {
+        let Ok((entity, id, material_name)) = mesh_materials.get(descendant) else {
+            continue;
+        };
+
+        if !material_name.starts_with("Fighter_") {
+            continue;
+        }
+
+        let Some(original_material) = original_materials.get(id.id()) else {
+            continue;
+        };
+
+        commands
+            .entity(entity)
+            .remove::<MeshMaterial3d<StandardMaterial>>()
+            .insert((
+                MeshMaterial3d(asset_materials.add(ExtendedMaterial {
+                    base: StandardMaterial {
+                        // can be used in forward or deferred mode
+                        ..original_material.clone()
+                    },
+                    extension: FighterMaterialExtension::new(
+                        bevy::color::palettes::css::BLUE.into(),
+                    ),
+                })),
+                FighterMesh {
+                    fighter: scene_ready.entity,
+                },
+            ));
+    }
+}

src/materials/mod.rs

@@ -0,0 +1,20 @@
+use bevy::{
+    asset::embedded_asset, prelude::*,
+};
+
+
+
+pub mod fighter_material;
+
+pub struct ShinesparkMaterialPlugin;
+
+
+impl Plugin for ShinesparkMaterialPlugin {
+    fn build(&self, app: &mut App) {
+        let omit_prefix = "";
+        embedded_asset!(app, omit_prefix, "shaders/fighter.wgsl");
+        app
+            .add_observer(fighter_material::bind_fighter_material)
+            .add_plugins(MaterialPlugin::<fighter_material::FighterMaterial>::default());
+    }
+}

src/materials/shaders/fighter.wgsl

@@ -0,0 +1,67 @@
+#import bevy_pbr::{
+    pbr_fragment::pbr_input_from_standard_material,
+    pbr_functions::alpha_discard,
+}
+
+#ifdef PREPASS_PIPELINE
+#import bevy_pbr::{
+    prepass_io::{VertexOutput, FragmentOutput},
+    pbr_deferred_functions::deferred_output,
+}
+#else
+#import bevy_pbr::{
+    forward_io::{VertexOutput, FragmentOutput},
+    pbr_functions::{apply_pbr_lighting, main_pass_post_lighting_processing},
+}
+#endif
+
+struct FighterExtendedMaterial {
+    status_color: vec4<f32>,
+    status_color_intensity: f32,
+#ifdef SIXTEEN_BYTE_ALIGNMENT
+    // Web examples WebGL2 support: structs must be 16 byte aligned.
+    _webgl2_padding_8b: u32,
+    _webgl2_padding_12b: u32,
+    _webgl2_padding_16b: u32,
+#endif
+}
+
+@group(#{MATERIAL_BIND_GROUP}) @binding(100)
+var<uniform> fighter_material: FighterExtendedMaterial;
+
+@fragment
+fn fragment(
+    in: VertexOutput,
+    @builtin(front_facing) is_front: bool,
+) -> FragmentOutput {
+    // generate a PbrInput struct from the StandardMaterial bindings
+    var pbr_input = pbr_input_from_standard_material(in, is_front);
+
+    // we can optionally modify the input before lighting and alpha_discard is applied
+    //pbr_input.material.base_color.b = pbr_input.material.base_color.r;
+
+    // alpha discard
+    pbr_input.material.base_color = alpha_discard(pbr_input.material, pbr_input.material.base_color);
+
+#ifdef PREPASS_PIPELINE
+    // in deferred mode we can't modify anything after that, as lighting is run in a separate fullscreen shader.
+    let out = deferred_output(in, pbr_input);
+#else
+    var out: FragmentOutput;
+    // apply lighting
+    out.color = apply_pbr_lighting(pbr_input);
+
+    // we can optionally modify the lit color before post-processing is applied
+    var quantize_steps: i32 = 2;
+    out.color = vec4<f32>(vec4<u32>(out.color * f32(quantize_steps))) / f32(quantize_steps);
+
+    // apply in-shader post processing (fog, alpha-premultiply, and also tonemapping, debanding if the camera is non-hdr)
+    // note this does not include fullscreen postprocessing effects like bloom.
+    out.color = main_pass_post_lighting_processing(pbr_input, out.color);
+
+    out.color = mix(out.color, fighter_material.status_color, fighter_material.status_color_intensity * 0.5);
+
+#endif
+
+    return out;
+}

src/math/mod.rs

@@ -3,3 +3,4 @@ pub mod segment;
 pub mod vec;
 pub mod fixed_transform;
 pub mod vec3;
+pub mod rect;

src/math/rect.rs

@@ -0,0 +1,12 @@
+use crate::math::vec::FGVec2;
+
+pub struct FGRect {
+    pub origin: FGVec2,
+    pub end: FGVec2,
+}
+
+impl FGRect {
+    pub fn contains_point(&self, point: FGVec2) -> bool {
+        point.x >= self.origin.x && point.y <= self.origin.y && point.x <= self.end.x && point.y >= self.end.y
+    }
+}

src/math/vec.rs

@@ -2,7 +2,7 @@ use bevy::math::Vec2;
 use bevy::prelude::*;
 use fixed::types::I32F32;
 use serde::{Deserialize, Serialize};
-use std::ops::{Add, AddAssign, Div, Mul, MulAssign, Sub};
+use std::ops::{Add, AddAssign, Div, Mul, MulAssign, Sub, SubAssign};
 
 use super::int::{FGWide, FGi32};
 
@@ -227,6 +227,15 @@ impl AddAssign for FGVec2 {
     }
 }
 
+impl SubAssign for FGVec2 {
+    fn sub_assign(&mut self, rhs: Self) {
+        *self = Self {
+            x: self.x - rhs.x,
+            y: self.y - rhs.y,
+        }
+    }
+}
+
 impl MulAssign for FGVec2 {
     fn mul_assign(&mut self, rhs: Self) {
         *self = Self {

src/menus/character_select/mod.rs

@@ -1,19 +1,8 @@
 use bevy::{picking::pointer::PointerId, prelude::*};
 
 use crate::{
-    AppState,
+    AppState, fighter::manifest::{FighterManifest, FighterManifestRegistry}, game_settings::CommonAssets, input::{LocalInputAssignments, LocalInputSource}, menus::{
-    fighter::manifest::{FighterManifest, FighterManifestRegistry},
+        MenuCameraMarker, MenuMarker, button::FGUiButton, character_select::{character_box::CharacterBox, token::CharacterSelectToken}, cursor::{FGMenuCursor, MenuCursorInputSource}, errors::MenuErrors::FighterManifestNotFound, match_config::{MenuMatchConfig, MenuMatchPlayerSlot}, scaling, spawn_menu, style::{FGUiButtonType, FGUiStyle},
-    game_settings::CommonAssets,
-    input::{LocalInputAssignments, LocalInputSource},
-    menus::{
-        MenuMarker,
-        button::FGUiButton,
-        character_select::{character_box::CharacterBox, token::CharacterSelectToken},
-        cursor::{FGMenuCursor, MenuCursorInputSource},
-        errors::MenuErrors::FighterManifestNotFound,
-        match_config::{MenuMatchConfig, MenuMatchPlayerSlot},
-        scaling, spawn_menu,
-        style::{FGUiButtonType, FGUiStyle},
     },
 };
 
@@ -241,7 +230,7 @@ pub fn copy_cursor_transform_to_token(
     character_boxes: Query<(&CharacterBox, &ComputedNode, &UiGlobalTransform)>,
     match_config: Res<MenuMatchConfig>,
     cursors: Query<&UiGlobalTransform, With<FGMenuCursor>>,
-    cam: Single<&Camera>,
+    cam: Single<&Camera, With<MenuCameraMarker>>,
     ui_scale: Res<UiScale>,
 ) -> Result {
     let camera = cam.into_inner();

src/menus/cursor.rs

@@ -9,11 +9,8 @@ use bevy::{
 };
 
 use crate::{
-    input::{LocalInputAssignments, LocalInputSource},
+    input::{LocalInputAssignments, LocalInputSource}, menus::{
-    menus::{
+        MenuCameraMarker, input::{MenuInput, MenuInputState}, scaling, style::FGUiStyle,
-        input::{MenuInput, MenuInputState},
-        scaling,
-        style::FGUiStyle,
     },
 };
 
@@ -181,7 +178,7 @@ pub fn cursor_input(
 }
 
 pub fn update_cursor_transform(
-    camera: Single<&Camera>,
+    camera: Single<&Camera, With<MenuCameraMarker>>,
     query: Query<(&mut Node, &PointerLocation), With<FGMenuCursor>>,
     ui_scale: Res<UiScale>,
 ) {

src/menus/input.rs

@@ -226,7 +226,7 @@ fn gamepad_input(
                 input.accept.accumulate(&status);
             }
             MenuInputMapAction::Start => {
-                input.accept.accumulate(&status);
+                input.start.accumulate(&status);
             }
         }
     }

src/menus/match_config.rs

@@ -65,7 +65,10 @@ impl MenuMatchConfig {
 
         let stage = self.stage.ok_or(MenuMatchConfigErrors::StageNotSelected)?;
 
-        for player in self.players.iter() {
+        let mut players = self.players.iter().collect::<Vec<_>>();
+        players.sort_unstable_by_key(|player| player.slot);
+
+        for (handle, player) in players.into_iter().enumerate() {
             let fighter_id =
                 player
                     .fighter
@@ -74,7 +77,8 @@ impl MenuMatchConfig {
                     ))?;
             match_players.push(MatchPlayer {
                 fighter: fighter_id,
-                handle: player.slot,
+                handle,
+                controller_port: player.slot,
             });
         }
 
@@ -102,4 +106,27 @@ mod tests {
 
         assert_eq!(menu.to_match_config().unwrap().rules, MatchRules::default());
     }
+
+    #[test]
+    fn sparse_controller_ports_get_dense_ggrs_handles() {
+        let menu = MenuMatchConfig {
+            stage: Some(StageId::TestStage),
+            players: vec![
+                MenuMatchPlayerSlot {
+                    slot: 3,
+                    fighter: Some(FighterId::TestFighter),
+                },
+                MenuMatchPlayerSlot {
+                    slot: 0,
+                    fighter: Some(FighterId::TestFighter),
+                },
+            ],
+        };
+
+        let config = menu.to_match_config().unwrap();
+        assert_eq!(config.players[0].handle, 0);
+        assert_eq!(config.players[0].controller_port, 0);
+        assert_eq!(config.players[1].handle, 1);
+        assert_eq!(config.players[1].controller_port, 3);
+    }
 }

src/menus/match_results/mod.rs

@@ -0,0 +1,44 @@
+use bevy::{prelude::*, text::FontSourceTemplate};
+
+use crate::{AppState, menus::{MenuMarker, spawn_menu}};
+
+pub fn setup_post_match_menu(
+    existing_menu: Option<Single<Entity, With<MenuMarker>>>,
+    commands: Commands,
+) {
+    let menu = bsn! {
+        Node {
+                flex_direction: FlexDirection::Column,
+                width: percent(100),
+                height: percent(100),
+                justify_content: JustifyContent::Center,
+                align_items: AlignItems::Center
+        }
+        Children [
+        (
+            Text("[Insert beautiful post-match screen here]")
+            TextFont {
+                font: FontSourceTemplate::Handle("fonts/roboto.ttf"),
+                font_size: px(super::style::H1_SIZE),
+            }
+            TextColor(Color::srgb(0.9, 0.9, 0.9))
+        ),
+            Text("Press any button/key to continue...")
+            TextFont {
+                font: FontSourceTemplate::Handle("fonts/roboto.ttf"),
+                font_size: px(super::style::H3_SIZE),
+            }
+            TextColor(Color::srgb(0.9, 0.9, 0.9))
+        ]
+    };
+
+    spawn_menu(existing_menu, commands, menu);
+}
+
+pub fn check_return_to_character_select(gamepads: Query<&Gamepad>, keyboard: Res<ButtonInput<KeyCode>>, mut next_state: ResMut<NextState<AppState>>) {
+    let any_pressed = gamepads.iter().any(|gp| gp.get_just_pressed().count() > 0);
+    let any_pressed = any_pressed || keyboard.get_just_pressed().count() > 0;
+    if any_pressed {
+        next_state.set(AppState::MainMenu);
+    }
+}

src/menus/mod.rs

@@ -18,6 +18,7 @@ pub mod errors;
 pub mod input;
 pub mod main_menu;
 pub mod match_config;
+pub mod match_results;
 pub mod navigation;
 pub mod scaling;
 pub mod stage_select;
@@ -53,6 +54,7 @@ pub fn wrap_menu(menu: impl Scene) -> impl Scene {
                 #MenuCamera
                 Camera
                 Camera2d
+                MenuCameraMarker
             ),
             (
                 #MenuContainer
@@ -73,17 +75,10 @@ pub fn wrap_menu(menu: impl Scene) -> impl Scene {
 
 pub fn despawn_menu(
     existing_menu: Option<Single<Entity, With<MenuMarker>>>,
-    existing_menu_camera: Option<Single<Entity, With<MenuCameraMarker>>>,
     mut commands: Commands,
 ) {
     if let Some(entity) = existing_menu {
-        commands
+        commands.entity(entity.into_inner()).despawn();
-            .entity(entity.into_inner())
-            .despawn();
-    }
-
-    if let Some(menu_cam) = existing_menu_camera {
-        commands.entity(*menu_cam).despawn();
     }
 }
 
@@ -93,9 +88,7 @@ pub fn spawn_menu(
     menu: impl Scene,
 ) {
     if let Some(entity) = existing_menu {
-        commands
+        commands.entity(entity.into_inner()).despawn();
-            .entity(entity.into_inner())
-            .despawn();
     }
     commands.queue_spawn_scene(wrap_menu(menu));
 }
@@ -120,115 +113,126 @@ where
 
 impl Plugin for MenuPlugin {
     fn build(&self, app: &mut App) {
-        app.add_systems(
+        app.add_systems(OnEnter(AppState::MainMenu), build_menu::<MainMenu>)
-            OnEnter(AppState::MainMenu),
+            .add_message::<character_select::PlayerSlotAssigned>()
-            build_menu::<MainMenu>,
+            .init_resource::<navigation::UINavigationActionState>()
-        )
+            .init_resource::<navigation::UINavigationRepeat>()
-        .add_message::<character_select::PlayerSlotAssigned>()
+            .init_resource::<input::MenuInputState>()
-        .init_resource::<navigation::UINavigationActionState>()
+            .insert_resource(InputFocusVisible(true))
-        .init_resource::<navigation::UINavigationRepeat>()
+            .insert_resource(GlobalUiDebugOptions { ..default() })
-        .init_resource::<input::MenuInputState>()
+            // Configure auto-navigation behavior
-        .insert_resource(InputFocusVisible(true))
+            .insert_resource(AutoNavigationConfig {
-        .insert_resource(GlobalUiDebugOptions {
+                // Require at least 10% overlap in perpendicular axis for cardinal directions
-            enabled: true,
+                min_alignment_factor: 0.1,
-            ..default()
+                // Don't connect nodes more than 500 pixels apart between their closest edges
-        })
+                max_search_distance: Some(500.0),
-        // Configure auto-navigation behavior
+                // Prefer nodes that are well-aligned
-        .insert_resource(AutoNavigationConfig {
+                prefer_aligned: true,
-            // Require at least 10% overlap in perpendicular axis for cardinal directions
+            })
-            min_alignment_factor: 0.1,
+            .add_plugins(DirectionalNavigationPlugin)
-            // Don't connect nodes more than 500 pixels apart between their closest edges
+            .add_systems(
-            max_search_distance: Some(500.0),
+                PreUpdate,
-            // Prefer nodes that are well-aligned
+                (
-            prefer_aligned: true,
+                    navigation::give_default_focus,
-        })
+                    scaling::ui_scaling_system,
-        .add_plugins(DirectionalNavigationPlugin)
+                    button::button_setup,
-        .add_systems(
+                    button::button_style_system.after(bevy::picking::PickingSystems::Hover),
-            PreUpdate,
+                    button::button_focus_style_system,
-            (
+                )
-                navigation::give_default_focus,
+                    .run_if(resource_exists::<CommonAssets>),
-                scaling::ui_scaling_system,
-                button::button_setup,
-                button::button_style_system.after(bevy::picking::PickingSystems::Hover),
-                button::button_focus_style_system,
             )
-                .run_if(resource_exists::<CommonAssets>),
+            .add_systems(Startup, scaling::ui_update_scale_on_startup)
-        )
+            // CURSOR
-        .add_systems(Startup, scaling::ui_update_scale_on_startup)
+            .add_systems(
-        // CURSOR
+                PreUpdate,
-        .add_systems(
+                (cursor::cursor_input).before(bevy::picking::PickingSystems::ProcessInput),
-            PreUpdate,
-            (cursor::cursor_input).before(bevy::picking::PickingSystems::ProcessInput),
-        )
-        .add_systems(
-            Update,
-            (cursor::copy_mouse_input, cursor::update_cursor_transform),
-        )
-        .add_systems(
-            PreUpdate,
-            input::sample_menu_inputs
-                .before(cursor::cursor_input)
-                .run_if(resource_exists::<crate::input::MenuInputMap>),
-        )
-        //---------
-        // CHARACTER SELECT START
-        //---------
-        .add_systems(
-            OnEnter(AppState::CharacterSelect),
-            character_select::setup_character_select,
-        )
-        .add_systems(
-            PostUpdate,
-            character_select::copy_cursor_transform_to_token
-                .run_if(in_state(AppState::CharacterSelect))
-                .run_if(any_with_component::<CharacterSelectScreen>),
-        )
-        .add_systems(
-            PreUpdate,
-            (
-                character_select::css_auto_assign_slots,
-                character_select::handle_fighter_slot_addition,
             )
-                .chain()
+            .add_systems(
-                .run_if(in_state(AppState::CharacterSelect))
+                Update,
-                .run_if(any_with_component::<CharacterSelectScreen>),
+                (cursor::copy_mouse_input, cursor::update_cursor_transform),
-        )
-        .add_systems(
-            OnExit(AppState::CharacterSelect),
-            (cursor::despawn_cursors, character_select::despawn_tokens),
-        )
-        .add_observer(character_select::select_fighter.run_if(in_state(AppState::CharacterSelect)))
-        .add_observer(
-            character_select::update_start_banner_visibility
-                .run_if(in_state(AppState::CharacterSelect)),
-        )
-        //---------
-        // CHARACTER SELECT END
-        //---------
-        //---------
-        // STAGE SELECT START
-        //---------
-        .add_systems(
-            OnEnter(AppState::StageSelect),
-            stage_select::setup_stage_select,
-        )
-        .add_observer(stage_select::stage_selected.run_if(in_state(AppState::StageSelect)))
-        .add_systems(
-            OnExit(AppState::StageSelect),
-            (cursor::despawn_cursors, despawn_menu),
-        )
-        //---------
-        // STAGE SELECT END
-        //---------
-        .add_systems(
-            Update,
-            (
-                navigation::process_inputs,
-                navigation::navigate,
-                navigation::interact_with_focused_button,
             )
-                .chain(),
+            .add_systems(
-        )
+                PreUpdate,
-        .init_resource::<InputFocus>();
+                input::sample_menu_inputs
+                    .before(cursor::cursor_input)
+                    .run_if(resource_exists::<crate::input::MenuInputMap>),
+            )
+            //---------
+            // CHARACTER SELECT START
+            //---------
+            .add_systems(
+                OnEnter(AppState::CharacterSelect),
+                character_select::setup_character_select,
+            )
+            .add_systems(
+                PostUpdate,
+                character_select::copy_cursor_transform_to_token
+                    .run_if(in_state(AppState::CharacterSelect))
+                    .run_if(any_with_component::<CharacterSelectScreen>),
+            )
+            .add_systems(
+                PreUpdate,
+                (
+                    character_select::css_auto_assign_slots,
+                    character_select::handle_fighter_slot_addition,
+                )
+                    .chain()
+                    .run_if(in_state(AppState::CharacterSelect))
+                    .run_if(any_with_component::<CharacterSelectScreen>),
+            )
+            .add_systems(
+                OnExit(AppState::CharacterSelect),
+                (cursor::despawn_cursors, character_select::despawn_tokens),
+            )
+            .add_observer(
+                character_select::select_fighter.run_if(in_state(AppState::CharacterSelect)),
+            )
+            .add_observer(
+                character_select::update_start_banner_visibility
+                    .run_if(in_state(AppState::CharacterSelect)),
+            )
+            //---------
+            // CHARACTER SELECT END
+            //---------
+            //---------
+            // STAGE SELECT START
+            //---------
+            .add_systems(
+                OnEnter(AppState::StageSelect),
+                stage_select::setup_stage_select,
+            )
+            .add_observer(stage_select::stage_selected.run_if(in_state(AppState::StageSelect)))
+            .add_systems(
+                OnExit(AppState::StageSelect),
+                (cursor::despawn_cursors, despawn_menu),
+            )
+            //---------
+            // STAGE SELECT END
+            //---------
+            //---------
+            // MATCH RESULT START
+            //---------
+            .add_systems(
+                OnEnter(AppState::MatchResults),
+                match_results::setup_post_match_menu,
+            )
+            .add_systems(
+                PostUpdate,
+                match_results::check_return_to_character_select
+                    .run_if(in_state(AppState::MatchResults)),
+            )
+            //---------
+            // MATCH RESULT END
+            //---------
+            .add_systems(
+                Update,
+                (
+                    navigation::process_inputs,
+                    navigation::navigate,
+                    navigation::interact_with_focused_button,
+                )
+                    .chain(),
+            )
+            .init_resource::<InputFocus>();
     }
 }

src/menus/navigation.rs

@@ -102,7 +102,7 @@ pub fn process_inputs(
                 .insert(DirectionalNavigationAction::Right);
         }
     }
-    if input.accept.is_pressed() {
+    if input.accept.is_just_pressed() {
         action_state
             .pressed_actions
             .insert(DirectionalNavigationAction::Select);
@@ -153,8 +153,8 @@ pub fn navigate(
             Ok(_entity) => {
                 // Successfully navigated
             }
-            Err(e) => {
+            Err(_e) => {
-                error!("Navigation error: {}", e)
+                //error!("Navigation error: {}", e)
             }
         }
     }

src/netcode/session.rs

@@ -42,6 +42,15 @@ pub enum SessionConfigError {
 }
 
 impl SessionConfig {
+    /// Returns whether this match has more than one remote participant.
+    pub fn is_multiplayer(&self) -> bool {
+        self.players.len() > 1
+            || self
+                .players
+                .iter()
+                .any(|player| matches!(player, PlayerConnection::Remote(_)))
+    }
+
     pub fn from_args(args: &Args, player_count: usize) -> Result<Self, SessionConfigError> {
         if player_count == 0 {
             return Err(SessionConfigError::NoPlayers);
@@ -196,6 +205,13 @@ mod tests {
             config.players,
             [PlayerConnection::Local, PlayerConnection::Local]
         );
+        assert!(config.is_multiplayer());
+    }
+
+    #[test]
+    fn single_local_player_is_not_multiplayer() {
+        let config = SessionConfig::from_args(&args(&["game", "--players", "1"]), 1).unwrap();
+        assert!(!config.is_multiplayer());
     }
 
     #[test]
@@ -207,6 +223,7 @@ mod tests {
         .unwrap();
         assert!(matches!(config.players[0], PlayerConnection::Local));
         assert!(matches!(config.players[1], PlayerConnection::Remote(_)));
+        assert!(config.is_multiplayer());
     }
 
     #[test]

src/player.rs

@@ -10,5 +10,8 @@ use bevy_ggrs::prelude::*;
 #[derive(Default, Component)]
 #[require(Rollback, Transform)]
 pub struct Player {
+    /// Dense GGRS session index.
     pub handle: usize,
+    /// Port used for port-dependent gameplay such as respawn placement.
+    pub controller_port: usize,
 }

src/replay.rs

@@ -17,7 +17,7 @@ use crate::{
 };
 
 const MAGIC: &[u8; 8] = b"SPRPLY01";
-pub const REPLAY_VERSION: u32 = 2;
+pub const REPLAY_VERSION: u32 = 3;
 
 #[derive(Clone, Copy, Debug, Default, Eq, PartialEq, ValueEnum)]
 pub enum ReplayFormat {
@@ -140,7 +140,7 @@ fn validate(replay: &Replay) -> Result<(), String> {
         ));
     }
     if replay.players_are_invalid() {
-        return Err("replay player handles must cover 0..player_count".into());
+        return Err("replay player handles must be unique".into());
     }
     if replay.frames.is_empty() {
         return Err("replay must contain at least one frame".into());
@@ -185,7 +185,7 @@ impl Replay {
             .map(|player| player.handle)
             .collect();
         handles.sort_unstable();
-        handles != (0..handles.len()).collect::<Vec<_>>()
+        handles.is_empty() || !handles.into_iter().eq(0..self.match_config.players.len())
     }
 
     fn frame(&self, frame: i32) -> Option<&ReplayFrame> {
@@ -374,6 +374,7 @@ mod tests {
                 stage: StageId::TestStage,
                 players: vec![MatchPlayer {
                     handle: 0,
+                    controller_port: 0,
                     fighter: FighterId::TestFighter,
                 }],
                 rules: MatchRules::Timed {

src/schedule.rs

@@ -9,22 +9,26 @@
 use bevy::prelude::*;
 use bevy_ggrs::prelude::*;
 
+use crate::match_runtime::match_is_ongoing;
+
 #[derive(SystemSet, Debug, Clone, PartialEq, Eq, Hash)]
 pub enum GameplaySet {
     /// Turn this frame's netcode inputs into per-fighter input state.
     Input,
     /// Decide whether the current fighter state hands off to another one.
     Interrupt,
+    /// Sample the animation pose selected by the interrupt pass.
+    Animation,
     /// Run the fighter state that survived the interrupt pass.
     StateUpdate,
     /// Integrate velocities into positions.
     Physics,
-    /// Solve collision boxes
-    Animation,
     /// Resolve the integrated positions against the stage.
     Collision,
     /// Resolve attacks
     Attacks,
+    /// Advance match rules and detect the end of the match.
+    MatchRules,
 }
 
 /// Declares the order of [`GameplaySet`] inside [`GgrsSchedule`]. Added by
@@ -38,13 +42,15 @@ impl Plugin for GameplaySchedulePlugin {
             (
                 GameplaySet::Input,
                 GameplaySet::Interrupt,
+                GameplaySet::Animation,
                 GameplaySet::StateUpdate,
                 GameplaySet::Physics,
                 GameplaySet::Collision,
-                GameplaySet::Animation,
                 GameplaySet::Attacks,
+                GameplaySet::MatchRules,
             )
-                .chain(),
+                .chain()
+                .run_if(match_is_ongoing),
         );
     }
 }

src/scripting/mod.rs

@@ -1,6 +1,5 @@
 use bevy::prelude::*;
 use serde::{Deserialize, Serialize};
-use std::collections::HashSet;
 
 use crate::{fighter::attack::AttackHitbox, math::int::FGi32};
 
@@ -15,22 +14,38 @@ pub enum MoveAngleKind {
 #[derive(Asset, Reflect, Serialize, Deserialize)]
 pub struct FighterAttackScript {
     pub hitboxes: Vec<AttackHitbox>,
-    pub iasa_frame: u32,
+    pub iasa_frame: Option<u32>,
-    pub wont_autocancel_window: (u32, u32),
+    pub wont_autocancel_window: Option<(u32, u32)>,
+    pub landing_duration: Option<u32>,
+    pub use_root_motion: bool
 }
 
 impl FighterAttackScript {
     pub fn validate(&self) -> Result<(), String> {
-        let mut ids = HashSet::with_capacity(self.hitboxes.len());
         for hitbox in &self.hitboxes {
             hitbox.validate()?;
-            if !ids.insert(hitbox.id) {
+        }
-                return Err(format!("duplicate hitbox id {}", hitbox.id));
+        for (index, left) in self.hitboxes.iter().enumerate() {
+            for right in self.hitboxes.iter().skip(index + 1) {
+                if left.id == right.id
+                    && left.start_frame < right.end_frame
+                    && right.start_frame < left.end_frame
+                {
+                    return Err(format!(
+                        "hitbox id {} has overlapping intervals {}..{} and {}..{}",
+                        left.id, left.start_frame, left.end_frame, right.start_frame,
+                        right.end_frame
+                    ));
+                }
             }
         }
-        if self.wont_autocancel_window.0 > self.wont_autocancel_window.1 {
+        
-            return Err("autocancel window end precedes its start".into());
+        if let Some(wont_autocancel_window) = self.wont_autocancel_window {
+            if wont_autocancel_window.0 > wont_autocancel_window.1 {
+                return Err("autocancel window end precedes its start".into());
+            }
         }
+
         Ok(())
     }
 }

src/scripting/move_compiler.rs

@@ -1,6 +1,7 @@
 use std::{cell::RefCell, collections::HashMap, rc::Rc};
 
 use rhai::EvalAltResult;
+use serde::{Deserialize, Serialize};
 
 use crate::{
     fighter::attack::{self, AttackAngle, FighterDamage, Knockback, KnockbackType},
@@ -10,11 +11,40 @@ use crate::{
 
 #[derive(Debug, Default)]
 struct MoveCompiler {
-    hitboxes: HashMap<u32, attack::AttackHitbox>,
+    hitboxes: Vec<attack::AttackHitbox>,
-    active_hitboxes: Vec<u32>,
+    active_hitboxes: HashMap<u32, usize>,
     wont_autocancel_window: Option<(u32, u32)>,
     iasa_frame: Option<u32>,
+    landing_duration: Option<u32>,
     cursor: u32,
+    use_root_motion: bool,
+}
+
+#[derive(Debug, Serialize, Deserialize, Clone)]
+pub struct SharedHitboxInfo {
+    damage: FighterDamage,
+    angle: AttackAngle,
+    knockback_type: KnockbackType,
+    knockback: Knockback,
+    knockback_growth: FGi32,
+}
+
+impl SharedHitboxInfo {
+    pub fn make(
+        damage: FighterDamage,
+        angle: AttackAngle,
+        knockback_type: KnockbackType,
+        knockback: Knockback,
+        knockback_growth: FGi32,
+    ) -> Self {
+        Self {
+            damage,
+            angle,
+            knockback_type,
+            knockback,
+            knockback_growth,
+        }
+    }
 }
 
 fn rhai_u32(value: i64, parameter: &str) -> Result<u32, Box<EvalAltResult>> {
@@ -43,28 +73,18 @@ impl MoveCompiler {
     }
 
     fn remove_hitbox(&mut self, id: u32) -> Result<(), Box<EvalAltResult>> {
-        let hb = self
+        let hitbox_index = *self
-            .hitboxes
+            .active_hitboxes
-            .get_mut(&id)
+            .get(&id)
             .ok_or(format!("Can't remove hitbox with {id}: Hitbox not found"))?;
-
+        self.hitboxes[hitbox_index].end_frame = self.cursor;
-        let active_hbox_position =
+        self.active_hitboxes.remove(&id);
-            self.active_hitboxes
-                .iter()
-                .position(|i| *i == id)
-                .ok_or(format!(
-                    "Can't remove hitbox with ID {id}: Hitbox was not active"
-                ))?;
-
-        hb.end_frame = self.cursor;
-
-        self.active_hitboxes.remove(active_hbox_position);
 
         Ok(())
     }
     fn remove_all_hitboxes(&mut self) -> Result<(), Box<EvalAltResult>> {
         // We are gonna modify the array, so take a copy...
-        for hitbox_id in self.active_hitboxes.clone() {
+        for hitbox_id in self.active_hitboxes.keys().copied().collect::<Vec<_>>() {
             self.remove_hitbox(hitbox_id)?;
         }
 
@@ -95,16 +115,21 @@ impl MoveCompiler {
         self.iasa_frame = Some(iasa_frame);
     }
 
+    fn enable_root_motion(&mut self) {
+        self.use_root_motion = true;
+    }
+
     fn into_attack_script(mut self) -> Result<FighterAttackScript, String> {
         self.remove_all_hitboxes().map_err(|err| err.to_string())?;
-        let mut hitboxes: Vec<_> = self.hitboxes.into_values().collect();
+        let mut hitboxes = self.hitboxes;
-        hitboxes.sort_unstable_by_key(|hitbox| hitbox.id);
+        hitboxes.sort_unstable_by_key(|hitbox| (hitbox.id, hitbox.start_frame));
-        let iasa_frame = self.iasa_frame.unwrap_or(100000);
+
-        let wont_autocancel_window = self.wont_autocancel_window.unwrap_or((0, 100000));
         Ok(FighterAttackScript {
             hitboxes,
-            iasa_frame,
+            iasa_frame: self.iasa_frame,
-            wont_autocancel_window,
+            wont_autocancel_window: self.wont_autocancel_window,
+            landing_duration: self.landing_duration,
+            use_root_motion: self.use_root_motion,
         })
     }
 }
@@ -117,7 +142,9 @@ pub fn register_common_types(engine: &mut rhai::Engine) {
         .register_fn("knockback_normal", KnockbackType::make_normal)
         .register_fn("knockback_fixed", KnockbackType::make_fixed)
         .register_type_with_name::<AttackAngle>("Angle")
-        .register_fn("angle", AttackAngle::make_normal)
+        .register_fn("angle", |str: &str| {
+            AttackAngle::make_normal(FGi32::lit(str))
+        })
         .register_fn("angle_sakurai", AttackAngle::make_sakurai)
         .register_type_with_name::<Knockback>("Knockback")
         .register_fn("knockback", Knockback::lit)
@@ -128,6 +155,17 @@ pub fn register_common_types(engine: &mut rhai::Engine) {
         .register_type_with_name::<FGVec3>("Vec3")
         .register_fn("vec3", FGVec3::lit)
         .register_type_with_name::<FighterDamage>("FighterDamage")
+        .register_type_with_name::<SharedHitboxInfo>("SharedHitboxInfo")
+        .register_fn(
+            "make_hitbox_info",
+            |damage: FighterDamage,
+             angle: AttackAngle,
+             knockback_type: KnockbackType,
+             knockback: Knockback,
+             knockback_growth: FGi32| {
+                SharedHitboxInfo::make(damage, angle, knockback_type, knockback, knockback_growth)
+            },
+        )
         .register_fn("damage", FighterDamage::lit);
 }
 
@@ -200,6 +238,48 @@ pub fn compile_script(text: &str) -> Result<FighterAttackScript, String> {
             );
         }
 
+        {
+            let mc = mc.clone();
+            engine.register_fn(
+                "enable_root_motion",
+                move || -> Result<(), Box<EvalAltResult>> {
+                    let mut b = mc.borrow_mut();
+                    b.enable_root_motion();
+                    Ok(())
+                },
+            );
+        }
+
+        {
+            let mc = mc.clone();
+            engine.register_fn(
+                "hitbox",
+                move |id: i64,
+                      group: i64,
+                      bone: &str,
+                      offset: FGVec3,
+                      radius: FGi32,
+                      shared: SharedHitboxInfo|
+                      -> Result<(), Box<EvalAltResult>> {
+                    add_hitbox(
+                        &mc,
+                        id,
+                        group,
+                        bone,
+                        shared.damage,
+                        offset,
+                        radius,
+                        shared.angle.clone(),
+                        shared.knockback_type,
+                        shared.knockback,
+                        shared.knockback_growth,
+                    )
+                },
+            );
+        }
+
+        // Keep the original script syntax working. Melee's default collision
+        // group is shared by all hitbox slots in an attack.
         {
             let mc = mc.clone();
             engine.register_fn(
@@ -214,18 +294,11 @@ pub fn compile_script(text: &str) -> Result<FighterAttackScript, String> {
                       knockback: Knockback,
                       knockback_growth: FGi32|
                       -> Result<(), Box<EvalAltResult>> {
-                    let mut b = mc.borrow_mut();
+                    add_hitbox(
-
+                        &mc,
-                    // Rhai does not have first class u32 support, so we have to do this.
-                    let id = rhai_u32(id, "hitbox id")?;
-
-                    if b.hitboxes.contains_key(&id) {
-                        return Err(format!("Hitbox with ID {} already existed!", id).into());
-                    }
-
-                    let hitbox = attack::AttackHitbox {
                         id,
-                        bone: bone.to_owned(),
+                        0,
+                        bone,
                         damage,
                         offset,
                         radius,
@@ -233,46 +306,110 @@ pub fn compile_script(text: &str) -> Result<FighterAttackScript, String> {
                         knockback_type,
                         knockback,
                         knockback_growth,
-                        start_frame: b.cursor,
+                    )
-                        end_frame: b.cursor,
+                },
-                    };
+            );
+        }
 
-                    b.hitboxes.insert(id, hitbox);
+        {
-                    b.active_hitboxes.push(id);
+            let mc = mc.clone();
-
+            engine.register_fn(
-                    Ok(())
+                "hitbox",
+                move |id: i64,
+                      group: i64,
+                      bone: &str,
+                      damage: FighterDamage,
+                      offset: FGVec3,
+                      radius: FGi32,
+                      angle: AttackAngle,
+                      knockback_type: KnockbackType,
+                      knockback: Knockback,
+                      knockback_growth: FGi32|
+                      -> Result<(), Box<EvalAltResult>> {
+                    add_hitbox(
+                        &mc,
+                        id,
+                        group,
+                        bone,
+                        damage,
+                        offset,
+                        radius,
+                        angle,
+                        knockback_type,
+                        knockback,
+                        knockback_growth,
+                    )
                 },
             );
         }
         engine.run(&text)
     };
-
+    let script = result
-    result
         .map(|_| {
             Rc::into_inner(mc)
                 .unwrap()
                 .into_inner()
                 .into_attack_script()
         })
-        .map_err(|err| err.to_string())?
+        .map_err(|err| err.to_string())??;
+    script.validate().map(|()| script)
+}
+
+fn add_hitbox(
+    mc: &Rc<RefCell<MoveCompiler>>,
+    raw_id: i64,
+    raw_group: i64,
+    bone: &str,
+    damage: FighterDamage,
+    offset: FGVec3,
+    radius: FGi32,
+    angle: AttackAngle,
+    knockback_type: KnockbackType,
+    knockback: Knockback,
+    knockback_growth: FGi32,
+) -> Result<(), Box<EvalAltResult>> {
+    let mut b = mc.borrow_mut();
+    let id = rhai_u32(raw_id, "hitbox id")?;
+    let group = rhai_u32(raw_group, "hitbox group")?;
+    if b.active_hitboxes.contains_key(&id) {
+        return Err(format!("Hitbox with ID {} is already active!", id).into());
+    }
+    let hitbox_index = b.hitboxes.len();
+    let frame = b.cursor;
+    b.hitboxes.push(attack::AttackHitbox {
+        id,
+        group,
+        bone: bone.to_owned(),
+        damage,
+        offset,
+        radius,
+        angle,
+        knockback_type,
+        knockback,
+        knockback_growth,
+        start_frame: frame,
+        end_frame: frame,
+    });
+    b.active_hitboxes.insert(id, hitbox_index);
+    Ok(())
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
-    const HITBOX: &str = "hitbox(0, \"hand_l\", damage(\"1\"), vec3(\"0\", \"0\", \"0\"), fg32(\"1\"), angle(fg32(\"0\")), knockback_normal(), knockback(\"1\"), fg32(\"1\"));";
+    const HITBOX: &str = "hitbox(0, \"hand_l\", damage(\"1\"), vec3(\"0\", \"0\", \"0\"), fg32(\"1\"), angle(\"0\"), knockback_normal(), knockback(\"1\"), fg32(\"1\"));";
 
     #[test]
     fn compiled_hitboxes_are_sorted_by_authored_id() {
         let script = compile_script(
             r#"
                 frame(1);
-                hitbox(20, "hand_l", damage("1"), vec3("0", "0", "0"), fg32("1"), angle(fg32("0")), knockback_normal(), knockback("1"), fg32("1"));
+                hitbox(20, "hand_l", damage("1"), vec3("0", "0", "0"), fg32("1"), angle("0"), knockback_normal(), knockback("1"), fg32("1"));
                 frame(2);
-                hitbox(3, "hand_l", damage("2"), vec3("0", "0", "0"), fg32("1"), angle(fg32("0")), knockback_normal(), knockback("1"), fg32("1"));
+                hitbox(3, "hand_l", damage("2"), vec3("0", "0", "0"), fg32("1"), angle("0"), knockback_normal(), knockback("1"), fg32("1"));
                 frame(3);
-                hitbox(10, "hand_l", damage("3"), vec3("0", "0", "0"), fg32("1"), angle(fg32("0")), knockback_normal(), knockback("1"), fg32("1"));
+                hitbox(10, "hand_l", damage("3"), vec3("0", "0", "0"), fg32("1"), angle("0"), knockback_normal(), knockback("1"), fg32("1"));
                 frame(4);
             "#,
         )
@@ -316,4 +453,44 @@ mod tests {
         assert_eq!(script.hitboxes[0].start_frame, 1);
         assert_eq!(script.hitboxes[0].end_frame, 2);
     }
+
+    #[test]
+    fn hitbox_ids_can_be_reused_after_removal() {
+        let script = compile_script(&format!(
+            "frame(1); {HITBOX} frame(2); remove_hitbox(0); frame(4); {HITBOX} frame(5);"
+        ))
+        .unwrap();
+
+        assert_eq!(script.hitboxes.len(), 2);
+        assert_eq!(script.hitboxes[0].start_frame, 1);
+        assert_eq!(script.hitboxes[0].end_frame, 2);
+        assert_eq!(script.hitboxes[1].start_frame, 4);
+        assert_eq!(script.hitboxes[1].end_frame, 5);
+    }
+
+    #[test]
+    fn explicit_hitbox_group_is_compiled() {
+        let script = compile_script(
+            r#"frame(1); hitbox(7, 3, "hand_l", damage("1"), vec3("0", "0", "0"), fg32("1"), angle("0"), knockback_normal(), knockback("1"), fg32("1")); frame(2);"#,
+        )
+        .unwrap();
+
+        assert_eq!(script.hitboxes[0].id, 7);
+        assert_eq!(script.hitboxes[0].group, 3);
+    }
+
+    #[test]
+    fn legacy_hitboxes_share_the_default_collision_group() {
+        let script = compile_script(
+            r#"
+                frame(1);
+                hitbox(0, "hand_l", damage("1"), vec3("0", "0", "0"), fg32("1"), angle("0"), knockback_normal(), knockback("1"), fg32("1"));
+                hitbox(1, "hand_l", damage("1"), vec3("0", "0", "0"), fg32("1"), angle("0"), knockback_normal(), knockback("1"), fg32("1"));
+                frame(2);
+            "#,
+        )
+        .unwrap();
+
+        assert_eq!(script.hitboxes.iter().map(|hitbox| hitbox.group).collect::<Vec<_>>(), vec![0, 0]);
+    }
 }

src/stage/debug.rs

@@ -1,10 +1,15 @@
 use bevy::{color::palettes::css::RED, prelude::*};
 
-use crate::stage::line::StageCollision;
+use crate::{
+    game_settings::GameSettings, match_loading::MatchConfig, math::{int::FGi32, vec3::FGVec3}, stage::{
+        line::{StageCollision, StageLedgeSide, StagePolyLineSegmentType}, manifest::{StageManifest, StageManifestRegistry},
+    },
+};
 
-pub fn debug_draw_scene(mut gizmos: Gizmos, stage_collision: Res<StageCollision>) {
+pub fn debug_draw_scene(mut gizmos: Gizmos, stage_collision: Res<StageCollision>, game_settings: Res<GameSettings>) {
     for poly in stage_collision.stage_polys.iter() {
-        for segment in poly.segments.iter() {
+        for (segment, next_segment) in poly.segments.iter().zip(poly.segments.iter().cycle().skip(1)) {
+            let wavedash_normal = ((next_segment.normal.to_vec2() + segment.normal.to_vec2()) * 0.5).normalize();
             let from = segment.segment.point1().to_vec2();
             let to = segment.segment.point2().to_vec2();
             let from_3d = Vec3::new(from.x, from.y, 0.0);
@@ -13,6 +18,79 @@ pub fn debug_draw_scene(mut gizmos: Gizmos, stage_collision: Res<StageCollision>
             gizmos.line(from_3d, end_3d, RED);
             let midpoint = (from_3d + end_3d) * 0.5;
             gizmos.arrow(midpoint, midpoint + normal_3d, RED);
+            if matches!(segment.segment_type, StagePolyLineSegmentType::Floor) {
+                let radius = game_settings.fighter_common.waveland_snap_distance.to_num::<f32>();
+                let a = segment.segment.point1().to_vec2();
+                let a = Vec3::new(a.x, a.y, 0.0);
+                let b = segment.segment.point2().to_vec2();
+                let b = Vec3::new(b.x, b.y, 0.0);
+                let offset = Vec3::new(wavedash_normal.x, wavedash_normal.y, 0.0) * radius;
+                gizmos.line(a + offset, b + offset, bevy::color::palettes::css::HOT_PINK);
+                gizmos.line(a - offset, b - offset, bevy::color::palettes::css::HOT_PINK);
+            }
         }
     }
+
+    for ledge in &stage_collision.ledges {
+        let position = ledge.position.to_vec2().extend(0.0);
+        let direction = match ledge.hang_side {
+            StageLedgeSide::Left => Vec3::NEG_X,
+            StageLedgeSide::Right => Vec3::X,
+        };
+        gizmos.circle(position, 1.5, bevy::color::palettes::css::LIME);
+        gizmos.arrow(
+            position,
+            position + direction * 4.0,
+            bevy::color::palettes::css::LIME,
+        );
+    }
+}
+
+pub fn debug_draw_blast_zones(
+    mut gizmos: Gizmos,
+    stage_registry: Res<StageManifestRegistry>,
+    stage_manifests: Res<Assets<StageManifest>>,
+    match_config: Res<MatchConfig>,
+) {
+    let Some(stage_manifest_handle) = stage_registry.get(match_config.stage) else {
+        return;
+    };
+
+    let Some(stage_manifest) = stage_manifests.get(&stage_manifest_handle) else {
+        return;
+    };
+
+    let top_left = stage_manifest.blast_zone_top_left.to_vec2();
+    let bottom_right = stage_manifest.blast_zone_bottom_right.to_vec2();
+    let center = (top_left + bottom_right) / 2.0;
+    let size = (bottom_right - top_left).abs();
+
+    gizmos.rect(
+        Vec3::new(center.x, center.y, 0.0),
+        size,
+        bevy::color::palettes::css::BLUE,
+    );
+}
+
+pub fn debug_draw_spawn_positions(
+    mut gizmos: Gizmos,
+    stage_registry: Res<StageManifestRegistry>,
+    stage_manifests: Res<Assets<StageManifest>>,
+    match_config: Res<MatchConfig>,
+) {
+    let Some(stage_manifest_handle) = stage_registry.get(match_config.stage) else {
+        return;
+    };
+
+    let Some(stage_manifest) = stage_manifests.get(&stage_manifest_handle) else {
+        return;
+    };
+
+    for spawn_point in stage_manifest.spawn_points.iter() {
+        gizmos.cross(FGVec3::new(spawn_point.x, spawn_point.y, FGi32::ZERO).to_vec3(), 2.0, bevy::color::palettes::css::BLUE);
+    }
+
+    for respawn_point in stage_manifest.respawn_points.iter() {
+        gizmos.cross(FGVec3::new(respawn_point.x, respawn_point.y, FGi32::ZERO).to_vec3(), 2.0, bevy::color::palettes::css::HOT_PINK);
+    }
 }

src/stage/line.rs

@@ -3,7 +3,7 @@
 use bevy::prelude::*;
 use serde::{Deserialize, Serialize};
 
-use crate::math::{segment::FGSegment2d, vec::FGVec2};
+use crate::math::{rect::FGRect, segment::FGSegment2d, vec::FGVec2};
 
 #[derive(Reflect, Clone, Copy, PartialEq, Serialize, Deserialize)]
 pub enum StagePolyLineSegmentType {
@@ -26,15 +26,36 @@ pub enum StagePolyType {
     Platform,
 }
 
-#[derive(Reflect, Hash, Debug, Clone, Copy, Default)]
+#[derive(Reflect, Hash, Debug, Clone, Copy, Default, PartialEq, Eq)]
 pub struct StageLineID {
     pub polygon: usize,
     pub segment: usize,
 }
 
+/// Identifies a corner in the stage collision geometry.
+#[derive(Reflect, Hash, Debug, Clone, Copy, Default, PartialEq, Eq)]
+pub struct StageVertexID {
+    pub polygon: usize,
+    pub vertex: usize,
+}
+
+/// The side of a ledge on which a grabbing fighter hangs.
+#[derive(Reflect, Serialize, Deserialize, Hash, Debug, Clone, Copy, PartialEq, Eq)]
+pub enum StageLedgeSide {
+    Left,
+    Right,
+}
+
+#[derive(Reflect, Hash, Debug, Clone, Copy, PartialEq)]
+pub struct StageLedge {
+    pub id: StageVertexID,
+    pub position: FGVec2,
+    pub hang_side: StageLedgeSide,
+}
+
 #[derive(Reflect, Clone, Default)]
 pub struct StagePoly {
-    poly_type: StagePolyType,
+    pub poly_type: StagePolyType,
     pub segments: Vec<StagePolyLineSegment>,
 }
 
@@ -44,10 +65,65 @@ pub struct StagePlaneIntersectResult {
     pub normal: FGVec2,
 }
 
+pub struct StageLedgeIntersectResult {
+    pub vertex_id: StageVertexID,
+    pub ledge_idx: usize
+}
+
+
 #[derive(Resource, Reflect, Clone, Default)]
 #[reflect(Resource)]
 pub struct StageCollision {
     pub stage_polys: Vec<StagePoly>,
+    pub ledges: Vec<StageLedge>,
+}
+
+impl StageCollision {
+    pub fn intersect_ledges(&self, ledge_grab_box: &FGRect) -> Option<StageLedgeIntersectResult> {
+        for (ledge_idx, ledge) in self.ledges.iter().enumerate() {
+            if ledge_grab_box.contains_point(ledge.position) {
+                return Some(StageLedgeIntersectResult {
+                    vertex_id: ledge.id,
+                    ledge_idx
+                });
+            }
+        }
+        None
+    }
+
+    pub fn find_ledge_by_vertex(&self, vertex: StageVertexID) -> Option<&StageLedge> {
+        self.ledges.iter().find(|ledge| ledge.id == vertex)
+    }
+
+    /// Returns the walkable segment on the stage side of a ledge.
+    pub fn find_ledge_ground_segment(
+        &self,
+        vertex: StageVertexID,
+    ) -> Option<(StageLineID, &StagePolyLineSegment)> {
+        let ledge = self.find_ledge_by_vertex(vertex)?;
+        let polygon = self.stage_polys.get(vertex.polygon)?;
+        let segment = match ledge.hang_side {
+            StageLedgeSide::Left => vertex.vertex,
+            StageLedgeSide::Right => {
+                if vertex.vertex > 0 {
+                    vertex.vertex - 1
+                } else if matches!(polygon.poly_type, StagePolyType::Closed) {
+                    polygon.segments.len().checked_sub(1)?
+                } else {
+                    return None;
+                }
+            }
+        };
+        let line_id = StageLineID {
+            polygon: vertex.polygon,
+            segment,
+        };
+        Some((line_id, polygon.get_segment(segment)?))
+    }
+
+    pub fn get_segment(&self, segment: StageLineID) -> Option<&StagePolyLineSegment> {
+        self.stage_polys.get(segment.polygon).map(|poly| poly.segments.get(segment.segment))?
+    }
 }
 
 impl StagePoly {

src/stage/manifest.rs

@@ -1,4 +1,4 @@
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 
 use bevy_asset_loader::asset_collection::AssetCollection;
 use ron_asset_manager::prelude::RonAsset;
@@ -7,14 +7,13 @@ use strum::IntoEnumIterator;
 use strum_macros::EnumIter;
 
 use crate::{
-    AppState,
+    AppState, game_settings::GameSettings, math::{vec::FGVec2}, stage::{
-    game_settings::GameSettings,
-    math::vec::FGVec2,
-    stage::{
         StagePoly,
-        line::{StageCollision, StagePolyLineSegmentType, StagePolyType},
+        line::{
-    },
+            StageCollision, StageLedge, StageLedgeSide, StagePolyLineSegment,
-    texture_reference::TextureReference,
+            StagePolyLineSegmentType, StagePolyType, StageVertexID,
+        },
+    }, texture_reference::TextureReference,
 };
 use bevy::prelude::*;
 
@@ -75,6 +74,16 @@ pub enum StageId {
 pub struct StagePolyDefinition {
     poly_type: StagePolyType,
     lines: Vec<(FGVec2, StagePolyLineSegmentType)>,
+    #[serde(default)]
+    ledges: Vec<StageLedgeDefinition>,
+}
+
+#[derive(Serialize, Deserialize, Clone, Copy, Reflect)]
+pub struct StageLedgeDefinition {
+    /// Index into the polygon's `lines`, identifying the corner position.
+    vertex: usize,
+    /// Side of the corner on which a grabbing fighter will hang.
+    hang_side: StageLedgeSide,
 }
 
 #[derive(Deserialize, Clone, Asset, Reflect, RonAsset)]
@@ -87,6 +96,17 @@ pub struct StageManifest {
     pub icon: TextureReference,
     pub camera: StageCameraProfile,
     pub polygons: Vec<StagePolyDefinition>,
+
+    #[reflect(ignore)]
+    pub blast_zone_top_left: FGVec2,
+    #[reflect(ignore)]
+    pub blast_zone_bottom_right: FGVec2,
+
+    #[reflect(ignore)]
+    pub spawn_points: Vec<FGVec2>,
+    pub neutral_spawn_point_sets: Vec<Vec<usize>>,
+    #[reflect(ignore)]
+    pub respawn_points: Vec<FGVec2>,
 }
 
 #[derive(Resource)]
@@ -162,6 +182,20 @@ pub fn prepare_stage_manifests(
             );
             return;
         }
+        if let Err(error) = manifest.validate_spawn_points() {
+            fail(
+                &mut next_state,
+                &format!("{:?} has invalid spawn points: {error}", manifest.id),
+            );
+            return;
+        }
+        if let Err(error) = manifest.validate_ledges() {
+            fail(
+                &mut next_state,
+                &format!("{:?} has invalid ledges: {error}", manifest.id),
+            );
+            return;
+        }
         if registry.insert(manifest.id, handle.clone()).is_some() {
             fail(
                 &mut next_state,
@@ -186,6 +220,81 @@ pub fn prepare_stage_manifests(
 }
 
 impl StageManifest {
+    pub fn neutral_spawn_positions(&self, player_count: usize) -> Result<Vec<FGVec2>, String> {
+        if player_count == 0 {
+            return Err("a match must contain at least one player".to_owned());
+        }
+
+        let layout = self
+            .neutral_spawn_point_sets
+            .get(player_count - 1)
+            .ok_or_else(|| format!("no spawn layout for {player_count} players"))?;
+
+        if layout.len() != player_count {
+            return Err(format!(
+                "the {player_count}-player layout contains {} positions",
+                layout.len()
+            ));
+        }
+
+        layout
+            .iter()
+            .map(|&index| {
+                self.spawn_points.get(index).copied().ok_or_else(|| {
+                    format!("the {player_count}-player layout references spawn point {index}")
+                })
+            })
+            .collect()
+    }
+
+    fn validate_spawn_points(&self) -> Result<(), String> {
+        if self.spawn_points.is_empty() {
+            return Err("no spawn points are configured".to_owned());
+        }
+
+        if self.respawn_points.is_empty() {
+            return Err("no respawn points are configured".to_owned());
+        }
+
+        if self.neutral_spawn_point_sets.is_empty() {
+            return Err("no neutral spawn layouts are configured".to_owned());
+        }
+
+        for (layout_index, layout) in self.neutral_spawn_point_sets.iter().enumerate() {
+            let player_count = layout_index + 1;
+            if layout.len() != player_count {
+                return Err(format!(
+                    "the {player_count}-player layout contains {} positions",
+                    layout.len()
+                ));
+            }
+
+            let mut unique_indices = HashSet::with_capacity(layout.len());
+            for &spawn_point_index in layout {
+                if spawn_point_index >= self.spawn_points.len() {
+                    return Err(format!(
+                        "the {player_count}-player layout references spawn point {spawn_point_index}"
+                    ));
+                }
+                if !unique_indices.insert(spawn_point_index) {
+                    return Err(format!(
+                        "the {player_count}-player layout uses spawn point {spawn_point_index} more than once"
+                    ));
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn validate_ledges(&self) -> Result<(), String> {
+        for (polygon_index, definition) in self.polygons.iter().enumerate() {
+            definition.validate_ledges(polygon_index)?;
+        }
+
+        Ok(())
+    }
+
     pub fn to_collision(&self) -> StageCollision {
         let stage_polys: Vec<StagePoly> = self
             .polygons
@@ -193,7 +302,84 @@ impl StageManifest {
             .map(|def| StagePoly::build(def.poly_type, &def.lines))
             .collect();
 
-        StageCollision { stage_polys }
+        let ledges = self
+            .polygons
+            .iter()
+            .enumerate()
+            .flat_map(|(polygon, definition)| definition.resolved_ledges(polygon))
+            .collect();
+
+        StageCollision {
+            stage_polys,
+            ledges,
+        }
+    }
+}
+
+impl StagePolyDefinition {
+    fn validate_ledges(&self, polygon_index: usize) -> Result<(), String> {
+        let polygon = StagePoly::build(self.poly_type, &self.lines);
+        let mut vertices = HashSet::with_capacity(self.ledges.len());
+
+        for ledge in &self.ledges {
+            if ledge.vertex >= self.lines.len() {
+                return Err(format!(
+                    "polygon {polygon_index} references missing vertex {}",
+                    ledge.vertex
+                ));
+            }
+            if !vertices.insert(ledge.vertex) {
+                return Err(format!(
+                    "polygon {polygon_index} defines vertex {} as a ledge more than once",
+                    ledge.vertex
+                ));
+            }
+
+            let outgoing = polygon.get_segment(ledge.vertex);
+            let incoming_index = if ledge.vertex > 0 {
+                Some(ledge.vertex - 1)
+            } else if matches!(self.poly_type, StagePolyType::Closed) {
+                polygon.segments.len().checked_sub(1)
+            } else {
+                None
+            };
+            let incoming = incoming_index.and_then(|index| polygon.get_segment(index));
+            let is_walkable_floor = |segment: Option<&StagePolyLineSegment>| {
+                segment.is_some_and(|segment| {
+                    segment.segment_type == StagePolyLineSegmentType::Floor
+                        && segment.normal.y > crate::math::int::FGi32::ZERO
+                })
+            };
+            let (interior, exterior) = match ledge.hang_side {
+                StageLedgeSide::Left => (outgoing, incoming),
+                StageLedgeSide::Right => (incoming, outgoing),
+            };
+            if !is_walkable_floor(interior) {
+                return Err(format!(
+                    "polygon {polygon_index} vertex {} has no upward-facing floor opposite its {:?} hang side",
+                    ledge.vertex, ledge.hang_side
+                ));
+            }
+            if is_walkable_floor(exterior) {
+                return Err(format!(
+                    "polygon {polygon_index} vertex {} is between two walkable floors rather than at an exposed corner",
+                    ledge.vertex
+                ));
+            }
+        }
+
+        Ok(())
+    }
+
+    fn resolved_ledges(&self, polygon: usize) -> impl Iterator<Item = StageLedge> + '_ {
+        self.ledges.iter().map(move |ledge| StageLedge {
+            id: StageVertexID {
+                polygon,
+                vertex: ledge.vertex,
+            },
+            position: self.lines[ledge.vertex].0,
+            hang_side: ledge.hang_side,
+        })
     }
 }
 
@@ -238,3 +424,115 @@ impl StageCameraProfile {
                 < 90.0
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::stage::line::StageLineID;
+
+    fn platform(ledges: Vec<StageLedgeDefinition>) -> StagePolyDefinition {
+        StagePolyDefinition {
+            poly_type: StagePolyType::Platform,
+            lines: vec![
+                (FGVec2::lit("-5", "0"), StagePolyLineSegmentType::Floor),
+                (FGVec2::lit("5", "0"), StagePolyLineSegmentType::Floor),
+            ],
+            ledges,
+        }
+    }
+
+    #[test]
+    fn platform_endpoints_can_be_defined_as_ledges() {
+        let definition = platform(vec![
+            StageLedgeDefinition {
+                vertex: 0,
+                hang_side: StageLedgeSide::Left,
+            },
+            StageLedgeDefinition {
+                vertex: 1,
+                hang_side: StageLedgeSide::Right,
+            },
+        ]);
+
+        assert_eq!(definition.validate_ledges(3), Ok(()));
+        let ledges = definition.resolved_ledges(3).collect::<Vec<_>>();
+        assert_eq!(ledges[0].id, StageVertexID { polygon: 3, vertex: 0 });
+        assert_eq!(ledges[0].position, FGVec2::lit("-5", "0"));
+        assert_eq!(ledges[1].id, StageVertexID { polygon: 3, vertex: 1 });
+        assert_eq!(ledges[1].position, FGVec2::lit("5", "0"));
+    }
+
+    #[test]
+    fn ledge_ground_segments_point_toward_the_stage_interior() {
+        let definition = platform(vec![
+            StageLedgeDefinition {
+                vertex: 0,
+                hang_side: StageLedgeSide::Left,
+            },
+            StageLedgeDefinition {
+                vertex: 1,
+                hang_side: StageLedgeSide::Right,
+            },
+        ]);
+        let collision = StageCollision {
+            stage_polys: vec![StagePoly::build(definition.poly_type, &definition.lines)],
+            ledges: definition.resolved_ledges(0).collect(),
+        };
+
+        for vertex in [0, 1] {
+            let (line_id, segment) = collision
+                .find_ledge_ground_segment(StageVertexID { polygon: 0, vertex })
+                .unwrap();
+            assert_eq!(line_id, StageLineID { polygon: 0, segment: 0 });
+            assert!(matches!(
+                segment.segment_type,
+                StagePolyLineSegmentType::Floor
+            ));
+        }
+    }
+
+    #[test]
+    fn invalid_and_duplicate_ledge_vertices_are_rejected() {
+        let missing = platform(vec![StageLedgeDefinition {
+            vertex: 2,
+            hang_side: StageLedgeSide::Right,
+        }]);
+        assert!(missing.validate_ledges(0).is_err());
+
+        let duplicate = platform(vec![
+            StageLedgeDefinition {
+                vertex: 0,
+                hang_side: StageLedgeSide::Left,
+            },
+            StageLedgeDefinition {
+                vertex: 0,
+                hang_side: StageLedgeSide::Right,
+            },
+        ]);
+        assert!(duplicate.validate_ledges(0).is_err());
+    }
+
+    #[test]
+    fn ledge_must_border_an_upward_facing_floor() {
+        let definition = StagePolyDefinition {
+            poly_type: StagePolyType::Platform,
+            lines: vec![
+                (FGVec2::lit("0", "0"), StagePolyLineSegmentType::Wall),
+                (FGVec2::lit("0", "5"), StagePolyLineSegmentType::Wall),
+            ],
+            ledges: vec![StageLedgeDefinition {
+                vertex: 0,
+                hang_side: StageLedgeSide::Left,
+            }],
+        };
+
+        assert!(definition.validate_ledges(0).is_err());
+
+        let wrong_side = platform(vec![StageLedgeDefinition {
+            vertex: 0,
+            hang_side: StageLedgeSide::Right,
+        }]);
+        assert!(wrong_side.validate_ledges(0).is_err());
+    }
+
+}

src/stage/mod.rs

@@ -10,7 +10,7 @@ pub mod scene;
 
 pub use line::{StagePlaneIntersectResult, StagePoly};
 
-use crate::stage::{line::StageCollision, manifest::StageCameraProfile};
+use crate::{match_loading::MatchConfig, stage::{line::StageCollision, manifest::StageCameraProfile}};
 
 /// Owns the stage geometry: which scene gets spawned and how it is drawn.
 #[derive(Default)]
@@ -20,9 +20,17 @@ impl Plugin for StagePlugin {
     fn build(&self, app: &mut App) {
         app.add_systems(
             Update,
-            debug::debug_draw_scene
+            (
-                .run_if(resource_exists::<line::StageCollision>)
+                (debug::debug_draw_scene
-                .run_if(crate::debug_tools::stage_collision_enabled),
+                    .run_if(resource_exists::<line::StageCollision>)
+                    .run_if(crate::debug_tools::stage_collision_enabled)),
+                (debug::debug_draw_blast_zones
+                    .run_if(resource_exists::<MatchConfig>)
+                    .run_if(crate::debug_tools::blast_zones_enabled),),
+                (debug::debug_draw_spawn_positions
+                    .run_if(resource_exists::<MatchConfig>)
+                    .run_if(crate::debug_tools::spawn_positions_enabled),),
+            ),
         );
     }
 }

src/ui/mod.rs

@@ -3,7 +3,7 @@ use bevy::prelude::*;
 use crate::{
     AppState,
     match_loading::{MatchConfig, MatchRules},
-    match_runtime::MatchState,
+    match_runtime::{MatchState, PauseState},
 };
 
 pub mod battle_ui;
@@ -11,6 +11,9 @@ pub mod errors;
 pub mod fighter_info;
 pub mod stock_icon;
 
+#[derive(Component)]
+pub struct PauseOverlay;
+
 #[derive(Default)]
 pub struct InGameUIPlugin;
 
@@ -30,8 +33,56 @@ impl Plugin for InGameUIPlugin {
                             } else {
                                 false
                             }
-                        }),
+                    }),
                 ),
-            );
+            )
+            .add_systems(Update, sync_pause_overlay);
+    }
+}
+
+pub fn sync_pause_overlay(
+    pause: Res<PauseState>,
+    overlay: Query<Entity, With<PauseOverlay>>,
+    mut commands: Commands,
+) {
+    if !pause.is_changed() {
+        return;
+    }
+
+    if pause.paused {
+        if overlay.is_empty() {
+            commands.spawn((
+                PauseOverlay,
+                Node {
+                    position_type: PositionType::Absolute,
+                    left: px(0),
+                    right: px(0),
+                    top: px(0),
+                    bottom: px(0),
+                    align_items: AlignItems::Center,
+                    justify_content: JustifyContent::Center,
+                    flex_direction: FlexDirection::Column,
+                    ..default()
+                },
+                BackgroundColor(Color::srgba(0.0, 0.0, 0.0, 0.7)),
+                ZIndex(100),
+                children![
+                    (
+                        Text::new("Paused"),
+                        TextFont::from_font_size(crate::menus::style::H1_SIZE as f32),
+                        TextColor(Color::WHITE),
+                    ),
+                    (
+                        Text::new("Press Esc or Start to resume"),
+                        TextFont::from_font_size(crate::menus::style::TEXT_SIZE as f32),
+                        TextColor(Color::WHITE),
+                    ),
+                ],
+            ));
+        }
+    } else {
+        for entity in &overlay {
+            commands.entity(entity).despawn();
+        }
     }
 }