Fix run direction not being taken into account when accelerating (Fixes #11)

Fixes #22

Extracts shared grounded collision/friction and airborne movement/landing policies while preserving state-specific behavior. Running fighters now pass `can_walk_off = true` so they can run off platform edges. Includes grounded and airborne hitstun call sites.

Reviewed-on: #36
Co-authored-by: Álex Román Núñez <eirexe@eirteam.moe>

.cargo/config.toml

@@ -1,7 +1,7 @@
 # for Linux
 [target.x86_64-unknown-linux-gnu]
 linker = "clang"
-rustflags = ["-C", "link-arg=-fuse-ld=/usr/bin/mold", "-Zshare-generics=y", ]
+rustflags = ["-C", "link-arg=-fuse-ld=/usr/bin/mold", "-Zshare-generics=y", "-D", "warnings", ]
 
 [unstable]
 codegen-backend = true

.gitea/workflows/ci.yml

@@ -10,7 +10,7 @@ on:
 jobs:
   build-and-test:
     runs-on: ubuntu-latest
-    timeout-minutes: 15
+    timeout-minutes: 30
     steps:
       - name: Check out source
         uses: actions/checkout@v4
@@ -20,7 +20,14 @@ jobs:
           curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | \
             sh -s -- -y --profile minimal
           echo "$HOME/.cargo/bin" >> "$GITHUB_PATH"
-          "$HOME/.cargo/bin/rustup" toolchain install nightly --profile minimal
+          "$HOME/.cargo/bin/rustup" toolchain install nightly-2026-09-14 --profile minimal
+
+      - name: Cache Rust dependencies and build artifacts
+        uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
+        with:
+          prefix-key: v1-rust
+          shared-key: linux-nightly
+          cache-bin: false
 
       - name: Install Linux dependencies
         run: |

rust-toolchain.toml

@@ -1,2 +1,2 @@
 [toolchain]
-channel = "nightly"
+channel = "nightly-2026-09-14"

src/debug_tools.rs

@@ -3,16 +3,19 @@
 use std::{collections::HashMap, time::Duration};
 
 use bevy::{
+    input::InputSystems,
     prelude::*,
     settings::{ReflectSettingsGroup, SaveSettingsDeferred, SettingsGroup},
 };
 use bevy_egui::{EguiContexts, EguiPrimaryContextPass, egui};
-use bevy_ggrs::RollbackFrameRate;
+use bevy_ggrs::{RollbackFrameRate, RunGgrsSystems};
 use enum_cycling::EnumCycle;
 use enum_cycling_derive::EnumCycle;
 
 use crate::{AppState, player::Player, replay::StopReplayRecording};
 
+mod save_state;
+
 pub const PLAYER_DEBUG_ROW_COUNT: usize = 6;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Reflect)]
@@ -48,7 +51,7 @@ impl PresentationMotionMode {
     }
 }
 
-#[derive(EnumCycle, Reflect)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, EnumCycle, Reflect)]
 pub enum GameSpeedDebug {
     Full,
     Half,
@@ -114,6 +117,7 @@ enum DebugFlag {
     Hurtboxes,
     Camera,
     DrawThroughGeometry,
+    FrameStepping,
 }
 
 #[derive(Clone, Copy)]
@@ -174,6 +178,10 @@ const WORLD_MENU: &[DebugMenuEntry] = &[
     DebugMenuEntry::GameSpeed {
         label: "Game speed",
     },
+    DebugMenuEntry::Toggle {
+        label: "Frame stepping",
+        flag: DebugFlag::FrameStepping,
+    },
 ];
 
 const DIAGNOSTICS_MENU: &[DebugMenuEntry] = &[DebugMenuEntry::Toggle {
@@ -233,6 +241,8 @@ pub struct DebugSettings {
     selections: Vec<usize>,
     #[reflect(ignore)]
     pub player_rows: HashMap<usize, [FighterDebugRowKind; PLAYER_DEBUG_ROW_COUNT]>,
+    #[reflect(ignore)]
+    pub frame_stepping: bool,
     pub network: bool,
     pub ecb: bool,
     pub stage_collision: bool,
@@ -253,6 +263,7 @@ impl Default for DebugSettings {
             pages: vec![DebugMenuPage::Static(ROOT_MENU)],
             selections: vec![0],
             player_rows: HashMap::new(),
+            frame_stepping: false,
             network: false,
             ecb: false,
             stage_collision: false,
@@ -325,6 +336,7 @@ impl DebugSettings {
             DebugFlag::Hurtboxes => self.hurtboxes,
             DebugFlag::DrawThroughGeometry => self.draw_through_geometry,
             DebugFlag::Camera => self.camera,
+            DebugFlag::FrameStepping => self.frame_stepping,
         }
     }
 
@@ -340,6 +352,7 @@ impl DebugSettings {
                 self.draw_through_geometry = !self.draw_through_geometry
             }
             DebugFlag::Camera => self.camera = !self.camera,
+            DebugFlag::FrameStepping => self.frame_stepping = !self.frame_stepping,
         }
     }
 
@@ -356,9 +369,35 @@ impl DebugSettings {
 
 pub struct DebugToolsPlugin;
 
+#[derive(Resource, Default)]
+struct FrameStepState {
+    requested: bool,
+    time_backup: Option<Time>,
+    last_step_time: Time
+}
+
 impl Plugin for DebugToolsPlugin {
     fn build(&self, app: &mut App) {
         app.init_resource::<DebugSettings>()
+            .init_resource::<FrameStepState>()
+            .init_resource::<save_state::DebugSaveState>()
+            .add_systems(OnEnter(AppState::InMatch), save_state::clear)
+            .add_systems(OnExit(AppState::InMatch), save_state::clear)
+            .add_systems(
+                PreUpdate,
+                prepare_frame_step
+                    .after(InputSystems)
+                    .before(RunGgrsSystems)
+                    .run_if(in_state(AppState::InMatch)),
+            )
+            .add_systems(
+                PreUpdate,
+                save_state::save_or_restore
+                    .after(InputSystems)
+                    .before(RunGgrsSystems)
+                    .run_if(in_state(AppState::InMatch)),
+            )
+            .add_systems(PreUpdate, restore_frame_step_time.after(RunGgrsSystems))
             .add_systems(
                 Update,
                 (handle_palette_input, sync_gizmo_depth_bias)
@@ -387,6 +426,141 @@ fn page_len(page: DebugMenuPage, player_handles: &[usize]) -> usize {
     }
 }
 
+fn queue_settings_save(commands: &mut Commands) {
+    commands.queue(SaveSettingsDeferred(Duration::from_secs_f32(0.1)));
+}
+
+fn frame_step_duration(frame_rate: usize) -> Duration {
+    Duration::from_nanos(1_000_000_000u64 / frame_rate as u64)
+}
+
+fn prepare_frame_step(
+    settings: Res<DebugSettings>,
+    gamepads: Query<&Gamepad>,
+    key: Res<ButtonInput<KeyCode>>,
+    mut state: ResMut<FrameStepState>,
+    mut time: ResMut<Time>,
+    frame_rate: Res<RollbackFrameRate>,
+) {
+    if !settings.frame_stepping {
+        state.requested = false;
+        return;
+    }
+
+    let pressed = gamepads
+        .iter()
+        .any(|gamepad| gamepad.pressed(GamepadButton::DPadDown));
+
+    let just_pressed = gamepads
+            .iter()
+            .any(|gamepad| gamepad.just_pressed(GamepadButton::DPadDown));
+
+    let just_pressed = key.just_pressed(KeyCode::F4) || just_pressed;
+    let pressed = key.pressed(KeyCode::F4) || pressed;
+
+    if just_pressed {
+        state.last_step_time = time.clone();
+    }
+
+    let can_repress = pressed && (time.elapsed() - state.last_step_time.elapsed()).as_millis() > 500;
+
+    if !settings.menu_open && (just_pressed || can_repress)
+    {
+        state.requested = true;
+    }
+
+    state.time_backup = Some(*time);
+    let delta = if state.requested {
+        frame_step_duration(**frame_rate)
+    } else {
+        Duration::ZERO
+    };
+    time.advance_by(delta);
+}
+
+fn restore_frame_step_time(mut state: ResMut<FrameStepState>, mut time: ResMut<Time>) {
+    if let Some(backup) = state.time_backup.take() {
+        *time = backup;
+        state.requested = false;
+    }
+}
+
+fn activate_selected(
+    settings: &mut DebugSettings,
+    page_len: usize,
+    player_handles: &[usize],
+    commands: &mut Commands,
+) {
+    if page_len == 0 {
+        return;
+    }
+
+    match settings.page() {
+        DebugMenuPage::Static(entries) => match entries[settings.selected()] {
+            DebugMenuEntry::StopRecording { .. } => {
+                commands.insert_resource(StopReplayRecording);
+            }
+            DebugMenuEntry::Toggle { flag, .. } => {
+                settings.toggle_flag(flag);
+                if !matches!(flag, DebugFlag::FrameStepping) {
+                    queue_settings_save(commands);
+                }
+            }
+            DebugMenuEntry::Submenu { entries, .. } => {
+                settings.push_page(DebugMenuPage::Static(entries));
+            }
+            DebugMenuEntry::PlayerSlots { .. } => settings.push_page(DebugMenuPage::PlayerList),
+            DebugMenuEntry::MotionSampling { .. } => {
+                settings.cycle_motion_sampling();
+                queue_settings_save(commands);
+            }
+            DebugMenuEntry::GameSpeed { .. } => {
+                commands.insert_resource(RollbackFrameRate(settings.game_speed.frame_rate()));
+                queue_settings_save(commands);
+            }
+        },
+        DebugMenuPage::PlayerList => {
+            let handle = player_handles[settings.selected()];
+            settings.rows_mut(handle);
+            settings.push_page(DebugMenuPage::PlayerRows(handle));
+        }
+        DebugMenuPage::PlayerRows(_) => {}
+    }
+}
+
+fn cycle_selected_value(settings: &mut DebugSettings, direction: i8, commands: &mut Commands) {
+    match settings.page() {
+        DebugMenuPage::Static(entries) => {
+            if let Some(entry) = entries.get(settings.selected()) {
+                match entry {
+                    DebugMenuEntry::MotionSampling { .. } => {
+                        settings.cycle_motion_sampling();
+                        queue_settings_save(commands);
+                    }
+                    DebugMenuEntry::GameSpeed { .. } => {
+                        settings.game_speed = if direction > 0 {
+                            settings.game_speed.up()
+                        } else {
+                            settings.game_speed.down()
+                        };
+                        commands
+                            .insert_resource(RollbackFrameRate(settings.game_speed.frame_rate()));
+                        queue_settings_save(commands);
+                    }
+                    _ => {}
+                }
+            }
+        }
+        DebugMenuPage::PlayerRows(handle) => {
+            let selected = settings.selected();
+            let rows = settings.rows_mut(handle);
+            rows[selected] = rows[selected].cycle(direction);
+            queue_settings_save(commands);
+        }
+        DebugMenuPage::PlayerList => {}
+    }
+}
+
 fn handle_palette_input(
     keyboard: Res<ButtonInput<KeyCode>>,
     gamepads: Query<(Entity, &Gamepad)>,
@@ -398,6 +572,15 @@ fn handle_palette_input(
         settings.toggle_flag(DebugFlag::DrawThroughGeometry);
     }
 
+    if keyboard.just_pressed(KeyCode::F3) {
+        settings.menu_open = !settings.menu_open;
+        settings.controller = None;
+        if settings.menu_open {
+            settings.reset_navigation();
+        }
+        return;
+    }
+
     if !settings.menu_open {
         for (entity, gamepad) in &gamepads {
             if gamepad.just_pressed(GamepadButton::Start) && gamepad.pressed(GamepadButton::DPadUp)
@@ -411,15 +594,16 @@ fn handle_palette_input(
         return;
     }
 
-    let Some(controller) = settings.controller else {
-        settings.menu_open = false;
-        return;
-    };
+    let gamepad = if let Some(controller) = settings.controller {
         let Ok((_, gamepad)) = gamepads.get(controller) else {
             settings.menu_open = false;
             settings.controller = None;
             return;
         };
+        Some(gamepad)
+    } else {
+        None
+    };
     let player_handles = player_handles(&players);
     let page = settings.page();
     let page_len = page_len(page, &player_handles);
@@ -428,95 +612,51 @@ fn handle_palette_input(
         *settings.selected_mut() = 0;
     }
 
-    if gamepad.just_pressed(GamepadButton::DPadUp) && page_len != 0 {
+    if (gamepad.is_some_and(|pad| pad.just_pressed(GamepadButton::DPadUp))
+        || keyboard.just_pressed(KeyCode::ArrowUp)
+        || keyboard.just_pressed(KeyCode::KeyW))
+        && page_len != 0
+    {
         let selected = settings.selected_mut();
         *selected = selected.checked_sub(1).unwrap_or(page_len - 1);
     }
-    if gamepad.just_pressed(GamepadButton::DPadDown) && page_len != 0 {
+    if (gamepad.is_some_and(|pad| pad.just_pressed(GamepadButton::DPadDown))
+        || keyboard.just_pressed(KeyCode::ArrowDown)
+        || keyboard.just_pressed(KeyCode::KeyS))
+        && page_len != 0
+    {
         let selected = settings.selected_mut();
         *selected = (*selected + 1) % page_len;
     }
 
-    let direction = if gamepad.just_pressed(GamepadButton::DPadLeft) {
+    let direction = if gamepad.is_some_and(|pad| pad.just_pressed(GamepadButton::DPadLeft))
+        || keyboard.just_pressed(KeyCode::ArrowLeft)
+        || keyboard.just_pressed(KeyCode::KeyA)
+    {
         Some(-1)
-    } else if gamepad.just_pressed(GamepadButton::DPadRight) {
+    } else if gamepad.is_some_and(|pad| pad.just_pressed(GamepadButton::DPadRight))
+        || keyboard.just_pressed(KeyCode::ArrowRight)
+        || keyboard.just_pressed(KeyCode::KeyD)
+    {
         Some(1)
     } else {
         None
     };
 
     if let Some(direction) = direction {
-        match page {
-            DebugMenuPage::Static(entries) => {
-                if let Some(entry) = entries.get(settings.selected()) {
-                    match entry {
-                        DebugMenuEntry::StopRecording { .. } => {}
-                        DebugMenuEntry::MotionSampling { .. } => settings.cycle_motion_sampling(),
-                        DebugMenuEntry::GameSpeed { .. } => {
-                            if direction > 0 {
-                                settings.game_speed = settings.game_speed.up();
-                            } else {
-                                settings.game_speed = settings.game_speed.down();
+        cycle_selected_value(&mut settings, direction, &mut commands);
     }
-
-                            commands.insert_resource(RollbackFrameRate(
-                                settings.game_speed.frame_rate(),
-                            ));
+    if (gamepad.is_some_and(|pad| pad.just_pressed(GamepadButton::South))
+        || keyboard.just_pressed(KeyCode::Enter)
+        || keyboard.just_pressed(KeyCode::Space))
+        && page_len != 0
+    {
+        activate_selected(&mut settings, page_len, &player_handles, &mut commands);
     }
-                        _ => {}
-                    }
-                }
-            }
-            DebugMenuPage::PlayerList => todo!(),
-            DebugMenuPage::PlayerRows(_) => {
-                let DebugMenuPage::PlayerRows(handle) = page else {
-                    unreachable!("player row navigation must have a player row page")
-                };
-                let selected = settings.selected();
-                let rows = settings.rows_mut(handle);
-                rows[selected] = rows[selected].cycle(direction);
-
-                commands.queue(SaveSettingsDeferred(Duration::from_secs_f32(0.1)));
-            }
-        }
-    }
-
-    if matches!(page, DebugMenuPage::PlayerRows(_)) {
-        let direction = if gamepad.just_pressed(GamepadButton::DPadLeft) {
-            Some(-1)
-        } else if gamepad.just_pressed(GamepadButton::DPadRight) {
-            Some(1)
-        } else {
-            None
-        };
-        if let Some(_direction) = direction {}
-    }
-    if gamepad.just_pressed(GamepadButton::South) {
-        match page {
-            DebugMenuPage::Static(entries) if page_len != 0 => match entries[settings.selected()] {
-                DebugMenuEntry::StopRecording { .. } => {
-                    commands.insert_resource(StopReplayRecording);
-                }
-                DebugMenuEntry::Toggle { flag, .. } => {
-                    settings.toggle_flag(flag);
-                    commands.queue(SaveSettingsDeferred(Duration::from_secs_f32(0.1)));
-                }
-                DebugMenuEntry::Submenu { entries, .. } => {
-                    settings.push_page(DebugMenuPage::Static(entries));
-                }
-                DebugMenuEntry::PlayerSlots { .. } => settings.push_page(DebugMenuPage::PlayerList),
-                DebugMenuEntry::MotionSampling { .. } => settings.cycle_motion_sampling(),
-                DebugMenuEntry::GameSpeed { .. } => {}
-            },
-            DebugMenuPage::PlayerList if page_len != 0 => {
-                let handle = player_handles[settings.selected()];
-                settings.rows_mut(handle);
-                settings.push_page(DebugMenuPage::PlayerRows(handle));
-            }
-            _ => {}
-        }
-    }
-    if gamepad.just_pressed(GamepadButton::West) && !settings.pop_page() {
+    if (gamepad.is_some_and(|pad| pad.just_pressed(GamepadButton::West))
+        || keyboard.just_pressed(KeyCode::Escape))
+        && !settings.pop_page()
+    {
         settings.menu_open = false;
         settings.controller = None;
     }
@@ -538,8 +678,9 @@ fn sync_gizmo_depth_bias(settings: Res<DebugSettings>, mut configs: ResMut<Gizmo
 
 fn draw_palette(
     mut contexts: EguiContexts,
-    settings: Res<DebugSettings>,
+    mut settings: ResMut<DebugSettings>,
     players: Query<&Player>,
+    mut commands: Commands,
 ) -> Result {
     if !settings.menu_open {
         return Ok(());
@@ -547,7 +688,7 @@ fn draw_palette(
 
     let player_handles = player_handles(&players);
     let page = settings.page();
-    let selected = settings.selected();
+    let page_len = page_len(page, &player_handles);
     egui::Window::new("Debug")
         .anchor(egui::Align2::RIGHT_TOP, egui::vec2(-12.0, 12.0))
         .resizable(false)
@@ -556,38 +697,113 @@ fn draw_palette(
             match page {
                 DebugMenuPage::Static(entries) => {
                     for (index, entry) in entries.iter().enumerate() {
-                        let marker = if index == selected { ">" } else { " " };
+                        ui.horizontal(|ui| {
+                            ui.label(if index == settings.selected() {
+                                ">"
+                            } else {
+                                " "
+                            });
                             match entry {
                                 DebugMenuEntry::StopRecording { label } => {
-                                ui.label(format!("{marker} {label}"));
+                                    if ui.button(*label).clicked() {
+                                        *settings.selected_mut() = index;
+                                        activate_selected(
+                                            &mut settings,
+                                            page_len,
+                                            &player_handles,
+                                            &mut commands,
+                                        );
+                                    }
                                 }
                                 DebugMenuEntry::Toggle { label, flag } => {
-                                let state = if settings.flag(*flag) { "on" } else { "off" };
-                                ui.label(format!("{marker} {label}: {state}"));
+                                    let mut value = settings.flag(*flag);
+                                    if ui.checkbox(&mut value, *label).changed() {
+                                        settings.toggle_flag(*flag);
+                                        if !matches!(flag, DebugFlag::FrameStepping) {
+                                            queue_settings_save(&mut commands);
+                                        }
+                                    }
                                 }
                                 DebugMenuEntry::Submenu { label, .. }
                                 | DebugMenuEntry::PlayerSlots { label } => {
-                                ui.label(format!("{marker} {label} >"));
+                                    if ui.button(format!("{label} >")).clicked() {
+                                        *settings.selected_mut() = index;
+                                        activate_selected(
+                                            &mut settings,
+                                            page_len,
+                                            &player_handles,
+                                            &mut commands,
+                                        );
+                                    }
                                 }
                                 DebugMenuEntry::MotionSampling { label } => {
-                                ui.label(format!(
-                                    "{marker} {label}: {}",
-                                    settings.motion_sampling.label()
-                                ));
+                                    let old = settings.motion_sampling;
+                                    egui::ComboBox::from_id_salt(("debug-motion", index))
+                                        .width(180.0)
+                                        .selected_text(format!("{label}: {}", old.label()))
+                                        .show_ui(ui, |ui| {
+                                            ui.selectable_value(
+                                                &mut settings.motion_sampling,
+                                                PresentationMotionMode::Interpolation,
+                                                "Interpolation",
+                                            );
+                                            ui.selectable_value(
+                                                &mut settings.motion_sampling,
+                                                PresentationMotionMode::Extrapolation,
+                                                "Extrapolation",
+                                            );
+                                        });
+                                    if settings.motion_sampling != old {
+                                        queue_settings_save(&mut commands);
+                                    }
                                 }
                                 DebugMenuEntry::GameSpeed { label } => {
-                                ui.label(format!(
-                                    "{marker} {label}: {}",
-                                    settings.game_speed.label()
+                                    let old = settings.game_speed;
+                                    egui::ComboBox::from_id_salt(("debug-speed", index))
+                                        .width(180.0)
+                                        .selected_text(format!("{label}: {}", old.label()))
+                                        .show_ui(ui, |ui| {
+                                            for speed in [
+                                                GameSpeedDebug::Full,
+                                                GameSpeedDebug::Half,
+                                                GameSpeedDebug::Quarter,
+                                            ] {
+                                                ui.selectable_value(
+                                                    &mut settings.game_speed,
+                                                    speed,
+                                                    speed.label(),
+                                                );
+                                            }
+                                        });
+                                    if settings.game_speed != old {
+                                        commands.insert_resource(RollbackFrameRate(
+                                            settings.game_speed.frame_rate(),
                                         ));
+                                        queue_settings_save(&mut commands);
                                     }
                                 }
                             }
+                        });
+                    }
                 }
                 DebugMenuPage::PlayerList => {
                     for (index, handle) in player_handles.iter().enumerate() {
-                        let marker = if index == selected { ">" } else { " " };
-                        ui.label(format!("{marker} Player {} >", handle + 1));
+                        ui.horizontal(|ui| {
+                            ui.label(if index == settings.selected() {
+                                ">"
+                            } else {
+                                " "
+                            });
+                            if ui.button(format!("Player {} >", handle + 1)).clicked() {
+                                *settings.selected_mut() = index;
+                                activate_selected(
+                                    &mut settings,
+                                    page_len,
+                                    &player_handles,
+                                    &mut commands,
+                                );
+                            }
+                        });
                     }
                     if player_handles.is_empty() {
                         ui.label("No players in match");
@@ -600,16 +816,30 @@ fn draw_palette(
                         .unwrap_or([FighterDebugRowKind::None; PLAYER_DEBUG_ROW_COUNT]);
                     ui.label(format!("Player {}", handle + 1));
                     for (index, row) in rows.iter().enumerate() {
-                        let marker = if index == selected { ">" } else { " " };
-                        ui.label(format!("{marker} Row {}: {}", index + 1, row.label()));
+                        ui.horizontal(|ui| {
+                            ui.label(if index == settings.selected() {
+                                ">"
+                            } else {
+                                " "
+                            });
+                            egui::ComboBox::from_id_salt(("debug-row", handle, index))
+                                .width(180.0)
+                                .selected_text(format!("Row {}: {}", index + 1, row.label()))
+                                .show_ui(ui, |ui| {
+                                    let rows = settings.rows_mut(handle);
+                                    for kind in FighterDebugRowKind::ALL {
+                                        ui.selectable_value(&mut rows[index], kind, kind.label());
+                                    }
+                                });
+                        });
                     }
                 }
             }
             ui.separator();
             let controls = if matches!(page, DebugMenuPage::PlayerRows(_)) {
-                "D-pad: select/change   B: back"
+                "Arrows/WASD: select/change   Escape/B: back"
             } else {
-                "D-pad: select   A: enter/toggle   Left/right: change   B: back"
+                "Arrows/WASD: select   Enter/A: activate   Escape/B: back"
             };
             ui.label(controls);
         });
@@ -699,4 +929,29 @@ mod tests {
         mode.cycle();
         assert_eq!(mode, PresentationMotionMode::Interpolation);
     }
+
+    #[test]
+    fn game_speed_has_expected_frame_rates() {
+        assert_eq!(GameSpeedDebug::Full.frame_rate(), 60);
+        assert_eq!(GameSpeedDebug::Half.frame_rate(), 30);
+        assert_eq!(GameSpeedDebug::Quarter.frame_rate(), 15);
+    }
+
+    #[test]
+    fn frame_stepping_is_disabled_by_default_and_uses_game_speed_timestep() {
+        let settings = DebugSettings::default();
+
+        assert!(!settings.frame_stepping);
+        assert_eq!(frame_step_duration(60), Duration::from_nanos(16_666_666));
+        assert_eq!(frame_step_duration(30), Duration::from_nanos(33_333_333));
+    }
+
+    #[test]
+    fn empty_player_list_does_not_activate() {
+        let mut settings = DebugSettings::default();
+        settings.push_page(DebugMenuPage::PlayerList);
+
+        assert_eq!(page_len(settings.page(), &[]), 0);
+        assert_eq!(settings.selected(), 0);
+    }
 }

src/debug_tools/save_state.rs

@@ -0,0 +1,197 @@
+use bevy::prelude::*;
+
+use crate::{
+    camera::MatchCamera,
+    fighter::{
+        FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop,
+        FighterPreviousFacingDirection, FighterPreviousTranslation, FighterTranslation,
+        FighterVelocity, Grounded,
+        animation::FighterAnimationFrame,
+        attack::{
+            FighterDamage, FighterKnockbackVelocity, FighterPendingHitReaction, FighterPendingHits,
+            FighterSolvedHurtboxes, FighterStaleMoveQueue,
+        },
+        baked_animation::FighterBoneMatrices,
+        state::FighterState,
+    },
+    input::FighterInput,
+    player::Player,
+    stage::line::StageCollision,
+};
+
+#[derive(Resource, Default)]
+pub(super) struct DebugSaveState {
+    checkpoint: Option<Checkpoint>,
+}
+
+#[derive(Clone)]
+struct Checkpoint {
+    fighters: Vec<FighterCheckpoint>,
+    stage_collision: StageCollision,
+    pending_hits: FighterPendingHits,
+}
+
+#[derive(Clone)]
+struct FighterCheckpoint {
+    entity: Entity,
+    handle: usize,
+    ecb: FighterECB,
+    previous_ecb: crate::fighter::ecb::FighterPreviousECB,
+    velocity: FighterVelocity,
+    translation: FighterTranslation,
+    previous_translation: FighterPreviousTranslation,
+    facing: FighterFacingDirection,
+    previous_facing: FighterPreviousFacingDirection,
+    animation: FighterAnimationFrame,
+    state: FighterState,
+    input: FighterInput,
+    damage: FighterDamage,
+    pending_hit_reaction: FighterPendingHitReaction,
+    hitstop: FighterHitstop,
+    knockback_velocity: FighterKnockbackVelocity,
+    stale_moves: FighterStaleMoveQueue,
+    hitboxes: FighterHitboxes,
+    solved_hurtboxes: FighterSolvedHurtboxes,
+    bone_matrices: FighterBoneMatrices,
+    grounded: bool,
+}
+
+pub(super) fn save_or_restore(world: &mut World) {
+    if world.resource::<super::DebugSettings>().menu_open {
+        return;
+    }
+
+    let left = world
+        .query::<&Gamepad>()
+        .iter(world)
+        .any(|gamepad| gamepad.just_pressed(GamepadButton::DPadLeft));
+    let right = world
+        .query::<&Gamepad>()
+        .iter(world)
+        .any(|gamepad| gamepad.just_pressed(GamepadButton::DPadRight));
+
+    if left == right {
+        return;
+    }
+
+    let Some(roster) = world
+        .get_resource::<crate::fighter::FighterRoster>()
+        .map(|roster| roster.0.clone())
+    else {
+        return;
+    };
+    if roster.len() != 1 {
+        warn!("Save states are only available in single-player matches");
+        return;
+    }
+
+    if left {
+        let Some(stage_collision) = world.get_resource::<StageCollision>().cloned() else {
+            return;
+        };
+        let mut checkpoint_fighters = Vec::with_capacity(roster.len());
+        for entity in roster.iter().copied() {
+            let Some(checkpoint) = capture_fighter(world, entity) else {
+                warn!("Could not save the current fighter state");
+                return;
+            };
+            checkpoint_fighters.push(checkpoint);
+        }
+        let pending_hits = world.resource::<FighterPendingHits>().clone();
+        world.resource_mut::<DebugSaveState>().checkpoint = Some(Checkpoint {
+            fighters: checkpoint_fighters,
+            stage_collision,
+            pending_hits,
+        });
+        info!("Saved debug game state");
+        return;
+    }
+
+    let Some(checkpoint) = world.resource::<DebugSaveState>().checkpoint.clone() else {
+        warn!("No debug game state has been saved");
+        return;
+    };
+    if checkpoint.fighters.len() != roster.len()
+        || checkpoint
+            .fighters
+            .iter()
+            .zip(roster.iter())
+            .any(|(saved, current)| saved.entity != *current)
+    {
+        warn!("Saved debug game state belongs to another match");
+        return;
+    }
+
+    for saved in &checkpoint.fighters {
+        let Some(player) = world.entity(saved.entity).get::<Player>() else {
+            warn!("Could not restore the saved fighter state");
+            return;
+        };
+        if player.handle != saved.handle {
+            warn!("Saved debug game state belongs to another match");
+            return;
+        }
+
+        let mut entity = world.entity_mut(saved.entity);
+        entity.insert(saved.ecb);
+        entity.insert(saved.previous_ecb);
+        entity.insert(saved.velocity);
+        entity.insert(saved.translation);
+        entity.insert(saved.previous_translation);
+        entity.insert(saved.facing);
+        entity.insert(saved.previous_facing);
+        entity.insert(saved.animation);
+        entity.insert(saved.state.clone());
+        entity.insert(saved.input);
+        entity.insert(saved.damage);
+        entity.insert(saved.pending_hit_reaction.clone());
+        entity.insert(saved.hitstop);
+        entity.insert(saved.knockback_velocity);
+        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(Grounded);
+        } else {
+            entity.remove::<Grounded>();
+        }
+    }
+    world.insert_resource(checkpoint.pending_hits.clone());
+    world.insert_resource(checkpoint.stage_collision);
+    for mut match_camera in world.query::<&mut MatchCamera>().iter_mut(world) {
+        match_camera.needs_snap = true;
+    }
+    info!("Restored debug game state");
+}
+
+fn capture_fighter(world: &World, entity: Entity) -> Option<FighterCheckpoint> {
+    let fighter = world.entity(entity);
+    Some(FighterCheckpoint {
+        entity,
+        handle: fighter.get::<Player>()?.handle,
+        ecb: *fighter.get::<FighterECB>()?,
+        previous_ecb: *fighter.get::<crate::fighter::ecb::FighterPreviousECB>()?,
+        velocity: *fighter.get::<FighterVelocity>()?,
+        translation: *fighter.get::<FighterTranslation>()?,
+        previous_translation: *fighter.get::<FighterPreviousTranslation>()?,
+        facing: *fighter.get::<FighterFacingDirection>()?,
+        previous_facing: *fighter.get::<FighterPreviousFacingDirection>()?,
+        animation: *fighter.get::<FighterAnimationFrame>()?,
+        state: fighter.get::<FighterState>()?.clone(),
+        input: *fighter.get::<FighterInput>()?,
+        damage: *fighter.get::<FighterDamage>()?,
+        pending_hit_reaction: fighter.get::<FighterPendingHitReaction>()?.clone(),
+        hitstop: *fighter.get::<FighterHitstop>()?,
+        knockback_velocity: *fighter.get::<FighterKnockbackVelocity>()?,
+        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>(),
+    })
+}
+
+pub(super) fn clear(mut save_state: ResMut<DebugSaveState>) {
+    save_state.checkpoint = None;
+}

src/fighter/attack/mod.rs

@@ -1,18 +1,19 @@
 use std::collections::{HashMap, VecDeque};
 
+mod reaction;
+
+use bevy::ecs::entity::{EntityMapper, MapEntities};
 use bevy::prelude::*;
-use bevy_ggrs::{Rollback, prelude::GgrsSchedule};
-use fixed_math::SinCos;
+use bevy_ggrs::{Rollback, RollbackApp, prelude::GgrsSchedule};
 use serde::{Deserialize, Serialize};
 
 use crate::{
     fighter::{
-        Fighter, FighterAttributes, FighterFacingDirection, FighterHitboxes, FighterHitstop,
+        Fighter, FighterAttributes, FighterFacingDirection, FighterHitboxes,
         FighterPreviousFacingDirection, FighterPreviousTranslation, FighterRoster,
         FighterTranslation,
         animation::{AnimKind, FighterAnimationFrame},
         baked_animation::{FighterBoneIndexMap, FighterBoneMatrices, FixedMat4},
-        errors::FighterErrors,
         hurtbox::{FixedAffineCapsule, FixedCapsule},
         manifest::FighterManifest,
     },
@@ -432,15 +433,26 @@ pub struct FighterAttackScriptAssets {
 #[derive(Component, Clone, Debug, Default, Hash)]
 pub struct FighterSolvedHurtboxes(pub Vec<FighterSolvedHurtbox>);
 
-#[derive(Component, Clone, Debug, Default, Hash, DerefMut, Deref)]
-pub struct FighterReceivedAttacks(
-    pub  Vec<(
-        /* attacker */ Entity,
-        Handle<FighterAttackScript>,
-        AttackKind,
-        /* hitbox_idx */ usize,
-    )>,
-);
+#[derive(Clone, Debug, Hash)]
+pub struct FighterHit {
+    pub attacker: Entity,
+    pub defender: Entity,
+    pub attack_script: Handle<FighterAttackScript>,
+    pub attack_kind: AttackKind,
+    pub hitbox_index: usize,
+}
+
+#[derive(Resource, Clone, Debug, Default, Hash)]
+pub struct FighterPendingHits(pub Vec<FighterHit>);
+
+impl MapEntities for FighterPendingHits {
+    fn map_entities<M: EntityMapper>(&mut self, entity_mapper: &mut M) {
+        for hit in &mut self.0 {
+            hit.attacker = entity_mapper.get_mapped(hit.attacker);
+            hit.defender = entity_mapper.get_mapped(hit.defender);
+        }
+    }
+}
 
 pub fn solve_hurtboxes(
     mut query: Query<(
@@ -498,19 +510,14 @@ pub fn intersect_attacks_with_hurtboxes(
         &Player,
         &FighterStaleMoveQueue,
     )>,
-    mut query_attacked: Query<(
-        Entity,
-        &FighterSolvedHurtboxes,
-        &Player,
-        &Fighter,
-        &mut FighterReceivedAttacks,
-    )>,
+    query_attacked: Query<(Entity, &FighterSolvedHurtboxes)>,
+    mut pending_hits: ResMut<FighterPendingHits>,
     attack_scripts: Res<Assets<FighterAttackScript>>,
 ) {
+    pending_hits.0.clear();
+
     for &entity_receiving in &roster.0 {
-        let Ok((_, hurtboxes, _, _receiving_fighter, mut received_attacks)) =
-            query_attacked.get_mut(entity_receiving)
-        else {
+        let Ok((_, hurtboxes)) = query_attacked.get(entity_receiving) else {
             continue;
         };
 
@@ -551,12 +558,13 @@ pub fn intersect_attacks_with_hurtboxes(
                 continue;
             };
 
-            received_attacks.push((
-                entity_hurting,
-                active_attack.script.clone(),
-                active_attack.kind,
-                hitting_hitbox_idx,
-            ));
+            pending_hits.0.push(FighterHit {
+                attacker: entity_hurting,
+                defender: entity_receiving,
+                attack_script: active_attack.script.clone(),
+                attack_kind: active_attack.kind,
+                hitbox_index: hitting_hitbox_idx,
+            });
             info!("Hit by hitbox {}!!!!", hitting_hitbox_idx);
 
             active_attack.hit_fighters.push(entity_receiving);
@@ -564,140 +572,21 @@ pub fn intersect_attacks_with_hurtboxes(
     }
 }
 
-pub fn calculate_received_attacks_trajectories(
-    mut attacker: Query<(
-        &mut FighterStaleMoveQueue,
-        &FighterFacingDirection,
-        &FighterHitboxes,
-        &Player,
-        &mut FighterHitstop,
-    )>,
-    receiver: Query<(
-        &mut FighterReceivedAttacks,
-        &mut FighterDamage,
-        &Fighter,
-        &mut FighterPendingHitReaction,
-    )>,
-    attack_scripts: Res<Assets<FighterAttackScript>>,
-    game_settings: Res<GameSettings>,
-    fighter_manifests: Res<Assets<FighterManifest>>,
-) -> Result {
-    for (mut received_attacks, mut receiver_damage, fighter, mut pending_reactions) in receiver {
-        if received_attacks.is_empty() {
-            continue;
-        }
-
-        // we got attacked, time to calculate the total damage
-
-        let damage_data = received_attacks
-            .iter()
-            .filter_map(|(from_entity, attack_script, attack_kind, hitbox_idx)| {
-                let Ok((stale_move_queue, facing_dir, _hitboxes, player, _attacker_hitstop)) =
-                    attacker.get(*from_entity)
-                else {
-                    return None;
-                };
-
-                let Some(attack_script) = attack_scripts.get(attack_script) else {
-                    return None;
-                };
-
-                let hitbox = &attack_script.hitboxes[*hitbox_idx];
-
-                let damage_received =
-                    stale_move_queue.get_attack_damage_multiplier(*attack_kind) * hitbox.damage.0;
-
-                Some((
-                    from_entity,
-                    damage_received,
-                    hitbox,
-                    attack_script,
-                    matches!(facing_dir, FighterFacingDirection::Left),
-                    player.handle,
-                ))
-            })
-            .collect::<Vec<_>>();
-
-        let total_damage_received_this_frame = damage_data
-            .iter()
-            .map(|(_, damage, ..)| damage)
-            .sum::<FGi32>();
-
-        let fighter_manifest = fighter_manifests
-            .get(&fighter.manifest)
-            .ok_or(FighterErrors::FighterManifestNotFound)?;
-
-        let mut reactions = vec![];
-
-        for (attacker_entity, attack_damage, hitbox, _attack_script, facing_left, attacker_slot) in
-            damage_data
-        {
-            let knockback = hitbox.calculate_knockback(
-                &fighter_manifest.attributes,
-                *receiver_damage,
-                FighterDamage(total_damage_received_this_frame),
-                false,
-                false,
-            );
-
-            let angle = match &hitbox.angle {
-                AttackAngle::Normal(angle) => *angle,
-                AttackAngle::Sakurai => FGi32::lit("32.0"),
-            };
-
-            let launch_angle = if facing_left {
-                FGi32::lit("180.0") - angle
-            } else {
-                angle
-            };
-            let (sin, cos) = launch_angle.sin_cos();
-            let launch_direction = FGVec2::new(cos, sin);
-            let hitstop = HitStop::calculate(FighterDamage(attack_damage), false);
-            reactions.push((
-                *attacker_entity,
-                attacker_slot,
-                FighterHitReaction {
-                    launch_velocity: launch_direction * knockback.get_launch_speed(&game_settings),
-                    hitstun_frames: knockback.get_hitstun_frames(&game_settings),
-                    hitstop_frames: hitstop,
-                    kind: HitReactionKind::Flinch,
-                },
-            ));
-        }
-
-        receiver_damage.0 += total_damage_received_this_frame;
-
-        for (attacker_entity, _, reaction) in reactions.iter() {
-            let Ok((.., mut hitstop)) = attacker.get_mut(*attacker_entity) else {
-                continue;
-            };
-
-            hitstop.remaining_frames = reaction.hitstop_frames.max(hitstop.remaining_frames);
-        }
-
-        // Pick attack by port priority
-        pending_reactions.0 = reactions
-            .into_iter()
-            .min_by(|(_, port_a, _), (_, port_b, _)| port_a.cmp(port_b))
-            .map(|(_, _, reaction)| reaction);
-
-        received_attacks.clear();
-    }
-
-    Ok(())
-}
-
 pub struct FighterAttackPlugin;
 
 impl Plugin for FighterAttackPlugin {
     fn build(&self, app: &mut App) {
+        app.init_resource::<FighterPendingHits>()
+            .add_plugins(reaction::FighterReactionPlugin)
+            .rollback_resource_with_clone::<FighterPendingHits>()
+            .update_resource_with_map_entities::<FighterPendingHits>()
+            .checksum_resource_with_hash::<FighterPendingHits>();
         app.add_systems(
             GgrsSchedule,
             (
                 solve_hurtboxes,
                 solve_hitboxes,
                 intersect_attacks_with_hurtboxes,
-                calculate_received_attacks_trajectories,
             )
                 .chain()
                 .after(crate::fighter::baked_animation::update_fighter_bone_matrices)

src/fighter/attack/reaction.rs

@@ -0,0 +1,145 @@
+use bevy::prelude::*;
+use bevy_ggrs::prelude::GgrsSchedule;
+use fixed_math::SinCos;
+
+use super::*;
+use crate::{
+    fighter::{
+        Fighter, FighterFacingDirection, FighterHitboxes, FighterHitstop,
+        FighterPendingHitReaction, FighterStaleMoveQueue, errors::FighterErrors,
+        manifest::FighterManifest,
+    },
+    game_settings::GameSettings,
+    math::{int::FGi32, vec::FGVec2},
+    player::Player,
+    schedule::GameplaySet,
+    scripting::FighterAttackScript,
+};
+
+pub fn resolve_fighter_hits(
+    mut pending_hits: ResMut<FighterPendingHits>,
+    mut attacker: Query<(
+        &FighterStaleMoveQueue,
+        &FighterFacingDirection,
+        &FighterHitboxes,
+        &Player,
+        &mut FighterHitstop,
+    )>,
+    mut receiver: Query<(&mut FighterDamage, &Fighter, &mut FighterPendingHitReaction)>,
+    attack_scripts: Res<Assets<FighterAttackScript>>,
+    game_settings: Res<GameSettings>,
+    fighter_manifests: Res<Assets<FighterManifest>>,
+) -> Result {
+    let hits = std::mem::take(&mut pending_hits.0);
+    let mut hit_offset = 0;
+
+    while hit_offset < hits.len() {
+        let defender = hits[hit_offset].defender;
+        let next_defender = hits[hit_offset..]
+            .iter()
+            .position(|hit| hit.defender != defender)
+            .map_or(hits.len(), |offset| hit_offset + offset);
+
+        let Ok((mut receiver_damage, fighter, mut pending_reaction)) = receiver.get_mut(defender)
+        else {
+            hit_offset = next_defender;
+            continue;
+        };
+
+        let damage_data = hits[hit_offset..next_defender]
+            .iter()
+            .filter_map(|hit| {
+                let Ok((stale_move_queue, facing_dir, _hitboxes, player, _)) =
+                    attacker.get(hit.attacker)
+                else {
+                    return None;
+                };
+                let attack_script = attack_scripts.get(&hit.attack_script)?;
+                let hitbox = attack_script.hitboxes.get(hit.hitbox_index)?;
+                let damage_received = stale_move_queue
+                    .get_attack_damage_multiplier(hit.attack_kind)
+                    * hitbox.damage.0;
+
+                Some((
+                    hit.attacker,
+                    damage_received,
+                    hitbox,
+                    matches!(facing_dir, FighterFacingDirection::Left),
+                    player.handle,
+                ))
+            })
+            .collect::<Vec<_>>();
+
+        let total_damage_received_this_frame = damage_data
+            .iter()
+            .map(|(_, damage, ..)| damage)
+            .sum::<FGi32>();
+        let fighter_manifest = fighter_manifests
+            .get(&fighter.manifest)
+            .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 knockback = hitbox.calculate_knockback(
+                &fighter_manifest.attributes,
+                *receiver_damage,
+                FighterDamage(total_damage_received_this_frame),
+                false,
+                false,
+            );
+            let angle = match &hitbox.angle {
+                AttackAngle::Normal(angle) => *angle,
+                AttackAngle::Sakurai => FGi32::lit("32.0"),
+            };
+            let launch_angle = if facing_left {
+                FGi32::lit("180.0") - angle
+            } else {
+                angle
+            };
+            let (sin, cos) = launch_angle.sin_cos();
+            let launch_direction = FGVec2::new(cos, sin);
+            let hitstop = HitStop::calculate(FighterDamage(attack_damage), false);
+            reactions.push((
+                attacker_entity,
+                attacker_slot,
+                FighterHitReaction {
+                    launch_velocity: launch_direction * knockback.get_launch_speed(&game_settings),
+                    hitstun_frames: knockback.get_hitstun_frames(&game_settings),
+                    hitstop_frames: hitstop,
+                    kind: HitReactionKind::Flinch,
+                },
+            ));
+        }
+
+        receiver_damage.0 += total_damage_received_this_frame;
+
+        for (attacker_entity, _, reaction) in &reactions {
+            let Ok((.., mut hitstop)) = attacker.get_mut(*attacker_entity) else {
+                continue;
+            };
+            hitstop.remaining_frames = reaction.hitstop_frames.max(hitstop.remaining_frames);
+        }
+
+        pending_reaction.0 = reactions
+            .into_iter()
+            .min_by(|(_, port_a, _), (_, port_b, _)| port_a.cmp(port_b))
+            .map(|(_, _, reaction)| reaction);
+
+        hit_offset = next_defender;
+    }
+
+    Ok(())
+}
+
+pub struct FighterReactionPlugin;
+
+impl Plugin for FighterReactionPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(
+            GgrsSchedule,
+            resolve_fighter_hits
+                .in_set(GameplaySet::Attacks)
+                .after(super::intersect_attacks_with_hurtboxes),
+        );
+    }
+}

src/fighter/collision.rs

@@ -1,9 +1,10 @@
 //! Resolving an integrated fighter position against the stage.
 
-use crate::fighter::state::FighterStateContext;
+use crate::fighter::ecb::FighterPreviousECB;
+use crate::fighter::{FighterECB, FighterPreviousTranslation, FighterTranslation};
 use crate::math::segment::FGSegment2d;
 use crate::math::vec::FGVec2;
-use crate::stage::line::StageLineID;
+use crate::stage::line::{StageCollision, StageLineID};
 /*
 pub fn collide_fighter_with_scene(
     fighters: Query<(&FighterECB, &mut FighterVelocity, &mut FighterTranslation)>,
@@ -38,16 +39,20 @@ pub struct AirCollisionWithStageResult {
 }
 
 pub fn air_collide_with_stage(
-    state_context: &FighterStateContext,
+    prev_translation: &FighterPreviousTranslation,
+    translation: &FighterTranslation,
+    prev_ecb: &FighterPreviousECB,
+    ecb: &FighterECB,
+    stage_collision: &StageCollision,
 ) -> Option<AirCollisionWithStageResult> {
     let ray_segment = FGSegment2d::new(
-        state_context.prev_translation.0 + state_context.prev_ecb.get_bottom_point(),
-        state_context.translation.0 + state_context.ecb.get_bottom_point(),
+        prev_translation.0 + prev_ecb.get_bottom_point(),
+        translation.0 + ecb.get_bottom_point(),
     );
 
     let mut intersect_results = vec![];
 
-    for (poly_idx, poly) in state_context.stage_collision.stage_polys.iter().enumerate() {
+    for (poly_idx, poly) in stage_collision.stage_polys.iter().enumerate() {
         if let Some(intersect_result) = poly.intersect_ray(ray_segment) {
             intersect_results.push((
                 AirCollisionWithStageResult {

src/fighter/mod.rs

@@ -33,17 +33,24 @@ pub use motion::{
 };
 
 use crate::{
-    AppState, fighter::{
+    AppState,
+    fighter::{
         attack::{
             AttackKind, FighterAttackPlugin, FighterAttackScriptAssets, FighterDamage,
-            FighterKnockbackVelocity, FighterPendingHitReaction, FighterReceivedAttacks,
-            FighterSolvedHurtboxes, FighterStaleMoveQueue,
+            FighterKnockbackVelocity, FighterPendingHitReaction, FighterSolvedHurtboxes,
+            FighterStaleMoveQueue,
         },
         baked_animation::{FighterBoneIndexMap, FighterBoneMatrices},
         manifest::FighterManifest,
         state::{FighterState, fall::FallState},
         visual::FighterAnimations,
-    }, input::FighterInput, math::{int::FGi32, vec::FGVec2}, player::Player, schedule::GameplaySet, scripting::FighterAttackScript, stage::line::StageCollision,
+    },
+    input::FighterInput,
+    math::{int::FGi32, vec::FGVec2},
+    player::Player,
+    schedule::GameplaySet,
+    scripting::FighterAttackScript,
+    stage::line::StageCollision,
 };
 use state::state_interrupt_system;
 
@@ -109,7 +116,6 @@ pub struct FighterVisual;
 
 #[derive(Component)]
 #[require(
-    FighterReceivedAttacks,
     FighterStaleMoveQueue,
     FighterDamage,
     FighterPendingHitReaction,
@@ -192,8 +198,6 @@ impl Plugin for FighterPlugin {
             .checksum_component_with_hash::<FighterHitstop>()
             .rollback_component_with_copy::<FighterKnockbackVelocity>()
             .checksum_component_with_hash::<FighterKnockbackVelocity>()
-            .rollback_component_with_clone::<FighterReceivedAttacks>()
-            .checksum_component_with_hash::<FighterReceivedAttacks>()
             .rollback_resource_with_reflect::<StageCollision>()
             // Debug views.
             .add_systems(
@@ -216,7 +220,8 @@ impl Plugin for FighterPlugin {
                         .after(debug::attack_debug_gather),
                 )
                     .chain()
-                    .run_if(crate::debug_tools::attack_hitboxes_enabled).run_if(in_state(AppState::InMatch)),
+                    .run_if(crate::debug_tools::attack_hitboxes_enabled)
+                    .run_if(in_state(AppState::InMatch)),
             )
             .add_systems(
                 FixedPostUpdate,

src/fighter/state/air.rs

@@ -1,3 +1,6 @@
+use crate::fighter::state::ground::GroundedStateCommon;
+use crate::fighter::state::land::{LandingState, LandingType};
+use crate::fighter::state::{CollisionContext, FighterState};
 use crate::fighter::*;
 
 pub fn integrate_gravity(velocity: &mut FighterVelocity, attributes: &FighterAttributes) {
@@ -53,6 +56,27 @@ pub fn apply_air_motion(
     translation.0 += velocity.0;
 }
 
+pub fn update_standard_motion(ctx: &mut crate::fighter::state::UpdateContext) {
+    integrate_gravity(ctx.velocity, ctx.fighter_attributes);
+    apply_air_drift(ctx.velocity, ctx.fighter_attributes, ctx.input);
+    apply_air_motion(ctx.velocity, ctx.translation, ctx.prev_translation);
+}
+
+pub fn collision_interrupt(
+    ctx: &mut CollisionContext,
+    landing_type: LandingType,
+) -> Option<FighterState> {
+    let res = ctx.air_collide_with_stage()?;
+    ctx.translation.0 = res.hit_position - ctx.ecb.get_bottom_point();
+    let grounded_common = GroundedStateCommon {
+        current_line_id: res.line_id,
+    };
+    Some(FighterState::Land(LandingState::create(
+        grounded_common,
+        landing_type,
+    )))
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/fighter/state/air_dodge.rs

@@ -1,12 +1,9 @@
 use crate::{
     fighter::{
         animation::AnimKind,
-        collision,
         state::{
-            FighterState, FighterStateContext, FighterStateImpl, air,
-            fall::FallState,
-            ground::GroundedStateCommon,
-            land::{LandingState, LandingType},
+            CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext,
+            UpdateContext, air, fall::FallState, land::LandingType,
         },
     },
     input,
@@ -21,7 +18,7 @@ pub struct AirDodgeState {
 impl FighterStateImpl for AirDodgeState {
     const NAME: &'static str = "AirDodge";
 
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if state_context.is_current_animation_finished() {
             Some(FighterState::Fall(FallState))
         } else {
@@ -29,8 +26,8 @@ impl FighterStateImpl for AirDodgeState {
         }
     }
 
-    fn update(&mut self, state_context: &mut FighterStateContext) {
-        state_context.velocity.0 *= state_context.fighter_manifest.attributes.air_dodge_decay;
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        state_context.velocity.0 *= state_context.fighter_attributes.air_dodge_decay;
 
         air::apply_air_motion(
             state_context.velocity,
@@ -41,32 +38,20 @@ impl FighterStateImpl for AirDodgeState {
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let Some(res) = collision::air_collide_with_stage(state_context) {
-            // Adjust translation
-            state_context.translation.0 = res.hit_position - state_context.ecb.get_bottom_point();
-            let grounded_common = GroundedStateCommon {
-                current_line_id: res.line_id,
-            };
-            Some(FighterState::Land(LandingState {
-                grounded_common,
-                landing_type: LandingType::Special,
-            }))
-        } else {
-            None
-        }
+        air::collision_interrupt(state_context, LandingType::Special)
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::AirDodge, false);
 
         state_context.velocity.0 =
-            self.direction * state_context.fighter_manifest.attributes.air_dodge_velocity;
+            self.direction * state_context.fighter_attributes.air_dodge_velocity;
     }
 }
 
-pub fn check_input(state_context: &FighterStateContext) -> Option<FighterState> {
+pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
     state_context
         .input
         .has_command(input::FighterCommands::Shield)

src/fighter/state/dash.rs

@@ -1,25 +1,19 @@
-use std::hash::Hasher;
-
-use super::{FighterStateContext, FighterStateImpl, ground, run, wait, walk};
+use super::{
+    CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext, ground, run,
+    wait, walk,
+};
 use crate::fighter::FighterFacingDirection;
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::FighterState;
-use crate::fighter::state::fall::FallState;
-use crate::fighter::state::ground::{GroundedMotionResult, GroundedStateCommon};
+use crate::fighter::state::ground::GroundedStateCommon;
 use crate::input::FighterCommands::{SmashMoveLeft, SmashMoveRight};
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Hash)]
 pub struct DashState {
     direction: FighterFacingDirection,
     pub ground_common: GroundedStateCommon,
 }
 
-impl std::hash::Hash for DashState {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        self.direction.hash(state);
-    }
-}
-
 impl DashState {
     pub fn new(direction: FighterFacingDirection, ground_common: GroundedStateCommon) -> Self {
         Self {
@@ -31,9 +25,9 @@ impl DashState {
 
 impl FighterStateImpl for DashState {
     const NAME: &'static str = "Dash";
-    fn check_interrupt(&self, ctx: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, ctx: &mut InterruptContext) -> Option<FighterState> {
         let ground = &self.ground_common;
-        let attributes = ctx.fighter_manifest.attributes;
+        let attributes = ctx.fighter_attributes;
 
         // A reverse dash can interrupt before IASA
         if let Some(direction) =
@@ -62,13 +56,10 @@ impl FighterStateImpl for DashState {
         None
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         *state_context.facing_direction = self.direction;
-        state_context.velocity.x = state_context
-            .fighter_manifest
-            .attributes
-            .dash_initial_velocity
-            * self.direction.to_sign();
+        state_context.velocity.x =
+            state_context.fighter_attributes.dash_initial_velocity * self.direction.to_sign();
 
         state_context.play_animation(AnimKind::Dash, false);
 
@@ -86,24 +77,20 @@ impl FighterStateImpl for DashState {
         }
     }
 
-    fn update(&mut self, state_context: &mut FighterStateContext) {
+    fn update(&mut self, state_context: &mut UpdateContext) {
         if state_context.get_current_animation_frame()
-            < state_context
-                .fighter_manifest
-                .attributes
-                .dash_acceleration_duration
+            < state_context.fighter_attributes.dash_acceleration_duration
         {}
 
         let last_frame = state_context.input.get_last_frame();
         let (accel, target_vel) = state_context
-            .fighter_manifest
-            .attributes
+            .fighter_attributes
             .get_accel_and_target_dashrun(&last_frame, self.direction.to_sign());
         let accel = ground::compute_ground_accel(
             accel,
             target_vel,
             state_context.velocity.x,
-            &state_context.fighter_manifest.attributes,
+            state_context.fighter_attributes,
             state_context.game_settings,
         );
         state_context.velocity.x += accel;
@@ -117,21 +104,13 @@ impl FighterStateImpl for DashState {
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.ground_common, true)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.ground_common, true)
     }
 }
 
-fn check_smash_input_with_dir(
-    state_context: &FighterStateContext,
-) -> Option<FighterFacingDirection> {
+fn check_smash_input_with_dir(state_context: &InterruptContext) -> Option<FighterFacingDirection> {
     if state_context.input.has_command(SmashMoveLeft) {
         return Some(FighterFacingDirection::Left);
     } else if state_context.input.has_command(SmashMoveRight) {
@@ -142,7 +121,7 @@ fn check_smash_input_with_dir(
 }
 
 pub fn check_input(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     check_smash_input_with_dir(state_context)

src/fighter/state/fall.rs

@@ -1,8 +1,5 @@
-use super::{FighterStateContext, FighterStateImpl};
+use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
 use crate::fighter::animation::AnimKind;
-use crate::fighter::collision;
-use crate::fighter::state::ground::GroundedStateCommon;
-use crate::fighter::state::land::{LandingState, LandingType};
 use crate::fighter::state::{FighterState, air, jump};
 
 #[derive(Debug, Clone, Copy, Hash)]
@@ -10,52 +7,30 @@ pub struct FallState;
 
 impl FighterStateImpl for FallState {
     const NAME: &'static str = "Fall";
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    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 super::FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::Fall, true);
     }
 
-    fn update(&mut self, state_context: &mut super::FighterStateContext) {
-        air::integrate_gravity(
-            state_context.velocity,
-            &state_context.fighter_manifest.attributes,
-        );
-        air::apply_air_drift(
-            state_context.velocity,
-            &state_context.fighter_manifest.attributes,
-            state_context.input,
-        );
-        air::apply_air_motion(
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        air::update_standard_motion(state_context);
     }
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let Some(res) = collision::air_collide_with_stage(state_context) {
-            // Adjust translation
-            state_context.translation.0 = res.hit_position - state_context.ecb.get_bottom_point();
-            let grounded_common = GroundedStateCommon {
-                current_line_id: res.line_id,
-            };
-            Some(FighterState::Land(LandingState::create(
-                grounded_common,
-                LandingType::Normal,
-            )))
-        } else {
-            None
-        }
+        air::collision_interrupt(
+            state_context,
+            crate::fighter::state::land::LandingType::Normal,
+        )
     }
 }
 
-pub fn check_input(state_context: &FighterStateContext) -> Option<FighterState> {
+pub fn check_input(state_context: &InterruptContext) -> 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 {

src/fighter/state/ground.rs

@@ -3,7 +3,7 @@
 //! bit-for-bit deterministic for rollback.
 
 use crate::fighter::state::{
-    FighterState, FighterStateContext, dash, ground_attack, turn, wait, walk,
+    CollisionContext, FighterState, InterruptContext, dash, fall, ground_attack, turn, wait, walk,
 };
 use crate::fighter::{
     FighterAttributes, FighterPreviousTranslation, FighterTranslation, FighterVelocity,
@@ -163,14 +163,30 @@ pub fn apply_grounded_motion(
     translation.0 += FGVec2::new(velocity.0.x, FGi32::ZERO);
 }
 
+pub fn update_friction_motion(ctx: &mut crate::fighter::state::UpdateContext) {
+    let friction = if ctx.velocity.x.abs() > ctx.fighter_attributes.max_walk_vel {
+        ctx.fighter_attributes.ground_friction
+            * ctx
+                .game_settings
+                .fighter_common
+                .ground_friction_over_walk_speed_multiplier
+    } else {
+        ctx.fighter_attributes.ground_friction
+    };
+
+    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);
+}
+
 pub fn collide_with_stage_grounded(
-    state_context: &mut FighterStateContext,
+    state_context: &mut CollisionContext,
     ground_common: &mut GroundedStateCommon,
     can_walk_off: bool,
 ) -> GroundedMotionResult {
     let translation = &mut state_context.translation;
-    let ecb = &state_context.ecb;
-    let stage_collision = &state_context.stage_collision;
+    let ecb = state_context.ecb;
+    let stage_collision = state_context.stage_collision;
 
     let stage_poly = stage_collision
         .stage_polys
@@ -210,6 +226,17 @@ pub fn collide_with_stage_grounded(
     }
 }
 
+pub fn collision_interrupt(
+    ctx: &mut CollisionContext,
+    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)),
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -322,14 +349,14 @@ mod tests {
 }
 
 pub fn grounded_movement_common_interrupts(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     super::jump::check_input(state_context, ground_common)
 }
 
 pub fn grounded_movement_standstill_common_interrupts(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     if let Some(state) = ground_attack::check_interrupt(state_context, &ground_common) {

src/fighter/state/ground_attack.rs

@@ -1,6 +1,9 @@
 use crate::fighter::{
     attack::{AttackKind, update_active_hitbox_list},
-    state::{FighterState, FighterStateImpl, ground::GroundedStateCommon, wait::WaitState},
+    state::{
+        CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl,
+        InterruptContext, UpdateContext, ground::GroundedStateCommon, wait::WaitState,
+    },
 };
 
 #[derive(Clone, Debug, Hash)]
@@ -12,10 +15,7 @@ pub struct GroundAttackState {
 impl FighterStateImpl for GroundAttackState {
     const NAME: &'static str = "GroundAttack";
 
-    fn check_interrupt(
-        &self,
-        state_context: &mut super::FighterStateContext,
-    ) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if state_context.is_current_animation_finished() {
             Some(FighterState::Wait(WaitState {
                 grounded_common: self.grounded_common.clone(),
@@ -25,7 +25,7 @@ impl FighterStateImpl for GroundAttackState {
         }
     }
 
-    fn update(&mut self, state_context: &mut super::FighterStateContext) {
+    fn update(&mut self, state_context: &mut UpdateContext) {
         let animation_frame = state_context.get_current_animation_frame();
         let script = state_context
             .attack_scripts
@@ -44,7 +44,7 @@ impl FighterStateImpl for GroundAttackState {
         }
     }
 
-    fn on_enter(&mut self, state_context: &mut super::FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(self.attack_kind.get_animation(), false);
         let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
         state_context.stale_move_queue.push(self.attack_kind);
@@ -57,20 +57,20 @@ impl FighterStateImpl for GroundAttackState {
         });
     }
 
-    fn on_exit(&mut self, state_context: &mut super::FighterStateContext) {
+    fn on_exit(&mut self, state_context: &mut ExitContext) {
         state_context.hitboxes.0 = None;
     }
 
     fn check_collision_interrupt(
         &mut self,
-        _state_context: &mut super::FighterStateContext,
+        _state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
         None
     }
 }
 
 pub fn check_interrupt(
-    state_context: &super::FighterStateContext,
+    state_context: &InterruptContext,
     grounded_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     if state_context

src/fighter/state/hitstun.rs

@@ -2,12 +2,12 @@ use crate::{
     fighter::{
         animation::AnimKind,
         attack::FighterHitReaction,
-        collision,
         state::{
-            FighterState, FighterStateContext, FighterStateImpl, air,
+            CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl,
+            InterruptContext, UpdateContext, air,
             fall::FallState,
-            ground::{GroundedMotionResult, GroundedStateCommon, collide_with_stage_grounded},
-            land::{LandingState, LandingType},
+            ground::{GroundedStateCommon, collision_interrupt},
+            land::LandingType,
             wait::WaitState,
         },
     },
@@ -43,7 +43,7 @@ impl FighterStateImpl for HitstunState {
         format!("Hitstun ({hitstop_kind}, {hit_reaction_type})")
     }
 
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    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) => {
@@ -58,8 +58,8 @@ impl FighterStateImpl for HitstunState {
         }
     }
 
-    fn update(&mut self, ctx: &mut FighterStateContext) {
-        air::integrate_gravity(ctx.velocity, &ctx.fighter_manifest.attributes);
+    fn update(&mut self, ctx: &mut UpdateContext) {
+        air::integrate_gravity(ctx.velocity, ctx.fighter_attributes);
 
         let speed = ctx.knockback_velocity.length();
         let next_speed = speed
@@ -71,7 +71,7 @@ impl FighterStateImpl for HitstunState {
         ctx.translation.0 += ctx.velocity.0 + ctx.knockback_velocity.0;
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         let animation = match self.hitstop_kind {
             HitstopStateKind::Grounded(_) => AnimKind::FlinchGround,
             HitstopStateKind::Airborne => AnimKind::FlinchAir,
@@ -80,37 +80,18 @@ impl FighterStateImpl for HitstunState {
         state_context.knockback_velocity.0 = self.hit_reaction.launch_velocity;
     }
 
-    fn on_exit(&mut self, _state_context: &mut FighterStateContext) {}
+    fn on_exit(&mut self, _state_context: &mut ExitContext) {}
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
         match &mut self.hitstop_kind {
             HitstopStateKind::Grounded(grounded_state_common) => {
-                if let GroundedMotionResult::InAir =
-                    collide_with_stage_grounded(state_context, grounded_state_common, true)
-                {
-                    Some(FighterState::Fall(FallState {}))
-                } else {
-                    None
-                }
+                collision_interrupt(state_context, grounded_state_common, true)
             }
             HitstopStateKind::Airborne => {
-                if let Some(res) = collision::air_collide_with_stage(state_context) {
-                    // Adjust translation
-                    state_context.translation.0 =
-                        res.hit_position - state_context.ecb.get_bottom_point();
-                    let grounded_common = GroundedStateCommon {
-                        current_line_id: res.line_id,
-                    };
-                    Some(FighterState::Land(LandingState::create(
-                        grounded_common,
-                        LandingType::Normal,
-                    )))
-                } else {
-                    None
-                }
+                air::collision_interrupt(state_context, LandingType::Normal)
             }
         }
     }

src/fighter/state/jump.rs

@@ -3,13 +3,11 @@ use bevy::prelude::*;
 use crate::{
     fighter::{
         animation::AnimKind,
-        collision,
         state::{
-            FighterState, FighterStateContext, FighterStateImpl, air,
+            CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext,
+            UpdateContext, air,
             air_dodge::{self, AirDodgeState},
-            fall::FallState,
-            ground::{self, GroundedMotionResult, GroundedStateCommon},
-            land::{LandingState, LandingType},
+            ground::{self, GroundedStateCommon},
         },
     },
     input::FighterCommands,
@@ -45,7 +43,7 @@ impl JumpSquatState {
 impl FighterStateImpl for JumpSquatState {
     const NAME: &'static str = "JumpSquat";
 
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         // 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
@@ -69,9 +67,7 @@ impl FighterStateImpl for JumpSquatState {
             Some(FighterState::AirDodge(AirDodgeState {
                 direction: wavedash_dir.normalize_or_zero(),
             }))
-        } else if self.duration_counter
-            >= state_context.fighter_manifest.attributes.jumpsquat_duration
-        {
+        } else if self.duration_counter >= state_context.fighter_attributes.jumpsquat_duration {
             info!("Jump {}", state_context.input.get_last_frame().jump);
             let jump_type = if state_context.input.get_last_frame().jump {
                 JumpType::LongJump
@@ -84,46 +80,19 @@ impl FighterStateImpl for JumpSquatState {
         }
     }
 
-    fn update(&mut self, state_context: &mut FighterStateContext) {
+    fn update(&mut self, state_context: &mut UpdateContext) {
         self.duration_counter += 1;
-
-        let friction = if state_context.velocity.x.abs()
-            > state_context.fighter_manifest.attributes.max_walk_vel
-        {
-            state_context.fighter_manifest.attributes.ground_friction
-                * state_context
-                    .game_settings
-                    .fighter_common
-                    .ground_friction_over_walk_speed_multiplier
-        } else {
-            state_context.fighter_manifest.attributes.ground_friction
-        };
-
-        let ground_velocity = state_context.velocity.x;
-
-        state_context.velocity.x += ground::apply_grounded_friction(friction, ground_velocity);
-
-        ground::apply_grounded_motion(
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
+        ground::update_friction_motion(state_context);
     }
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, false)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::JumpSquat, false);
         state_context.input.clear_command(FighterCommands::Jump);
     }
@@ -131,7 +100,7 @@ impl FighterStateImpl for JumpSquatState {
 
 impl FighterStateImpl for JumpState {
     const NAME: &'static str = "Jump";
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if state_context.input.has_command(FighterCommands::Jump) {
             Some(FighterState::Jump(JumpState {
                 jump_type: JumpType::DoubleJump,
@@ -141,24 +110,11 @@ impl FighterStateImpl for JumpState {
         }
     }
 
-    fn update(&mut self, state_context: &mut FighterStateContext) {
-        air::integrate_gravity(
-            state_context.velocity,
-            &state_context.fighter_manifest.attributes,
-        );
-        air::apply_air_drift(
-            state_context.velocity,
-            &state_context.fighter_manifest.attributes,
-            state_context.input,
-        );
-        air::apply_air_motion(
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        air::update_standard_motion(state_context);
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         if let JumpType::DoubleJump = self.jump_type {
             state_context.input.clear_command(FighterCommands::Jump);
         }
@@ -185,42 +141,22 @@ impl FighterStateImpl for JumpState {
         }
 
         let vertical_vel = match self.jump_type {
-            JumpType::ShortHop => {
-                state_context
-                    .fighter_manifest
-                    .attributes
-                    .short_hop_vertical_velocity
-            }
-            JumpType::LongJump => {
-                state_context
-                    .fighter_manifest
-                    .attributes
-                    .full_jump_vertical_velocity
-            }
+            JumpType::ShortHop => state_context.fighter_attributes.short_hop_vertical_velocity,
+            JumpType::LongJump => state_context.fighter_attributes.full_jump_vertical_velocity,
             JumpType::DoubleJump => {
-                state_context
-                    .fighter_manifest
-                    .attributes
-                    .full_jump_vertical_velocity
-                    * state_context
-                        .fighter_manifest
-                        .attributes
-                        .air_jump_multiplier
+                state_context.fighter_attributes.full_jump_vertical_velocity
+                    * state_context.fighter_attributes.air_jump_multiplier
             }
         };
 
         match self.jump_type {
             JumpType::ShortHop | JumpType::LongJump => {
-                state_context.velocity.x += state_context
-                    .fighter_manifest
-                    .attributes
-                    .jump_horizontal_velocity
-                    * movement_stick_x;
+                state_context.velocity.x +=
+                    state_context.fighter_attributes.jump_horizontal_velocity * movement_stick_x;
             }
             JumpType::DoubleJump => {
                 state_context.velocity.x = state_context
-                    .fighter_manifest
-                    .attributes
+                    .fighter_attributes
                     .air_jump_horizontal_velocity
                     * movement_stick_x;
             }
@@ -231,26 +167,17 @@ impl FighterStateImpl for JumpState {
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let Some(res) = collision::air_collide_with_stage(state_context) {
-            // Adjust translation
-            state_context.translation.0 = res.hit_position - state_context.ecb.get_bottom_point();
-            let grounded_common = GroundedStateCommon {
-                current_line_id: res.line_id,
-            };
-            Some(FighterState::Land(LandingState::create(
-                grounded_common,
-                LandingType::Normal,
-            )))
-        } else {
-            None
-        }
+        air::collision_interrupt(
+            state_context,
+            crate::fighter::state::land::LandingType::Normal,
+        )
     }
 }
 
 pub fn check_input(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     state_context
@@ -259,7 +186,7 @@ pub fn check_input(
         .then(|| FighterState::JumpSquat(JumpSquatState::create(ground_common.clone())))
 }
 
-pub fn check_input_double_jump(state_context: &FighterStateContext) -> Option<FighterState> {
+pub fn check_input_double_jump(state_context: &InterruptContext) -> Option<FighterState> {
     state_context
         .input
         .has_command(FighterCommands::Jump)

src/fighter/state/land.rs

@@ -1,12 +1,9 @@
 use crate::fighter::{
     animation::AnimKind,
     state::{
-        FighterState, FighterStateContext, FighterStateImpl, dash,
-        fall::FallState,
-        ground::{
-            self, GroundedMotionResult, GroundedStateCommon,
-            grounded_movement_standstill_common_interrupts,
-        },
+        CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext,
+        UpdateContext, dash,
+        ground::{self, GroundedStateCommon, grounded_movement_standstill_common_interrupts},
         walk,
     },
 };
@@ -35,11 +32,11 @@ impl LandingState {
 impl FighterStateImpl for LandingState {
     const NAME: &'static str = "Landing";
 
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    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)
         } else if state_context.get_current_animation_frame()
-            >= state_context.fighter_manifest.attributes.landing_iasa
+            >= state_context.fighter_attributes.landing_iasa
             && let LandingType::Normal = self.landing_type
         {
             dash::check_input(state_context, &self.grounded_common).or_else(|| {
@@ -51,44 +48,18 @@ impl FighterStateImpl for LandingState {
         }
     }
 
-    fn update(&mut self, state_context: &mut FighterStateContext) {
-        let friction = if state_context.velocity.x.abs()
-            > state_context.fighter_manifest.attributes.max_walk_vel
-        {
-            state_context.fighter_manifest.attributes.ground_friction
-                * state_context
-                    .game_settings
-                    .fighter_common
-                    .ground_friction_over_walk_speed_multiplier
-        } else {
-            state_context.fighter_manifest.attributes.ground_friction
-        };
-
-        let ground_velocity = state_context.velocity.x;
-
-        state_context.velocity.x += ground::apply_grounded_friction(friction, ground_velocity);
-
-        ground::apply_grounded_motion(
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        ground::update_friction_motion(state_context);
     }
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, true)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.grounded_common, true)
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         match self.landing_type {
             LandingType::Normal => {
                 state_context.play_animation(AnimKind::Landing, false);

src/fighter/state/mod.rs

@@ -10,6 +10,7 @@ use crate::fighter::attack::{
     FighterAttackScriptAssets, FighterKnockbackVelocity, FighterPendingHitReaction,
     FighterStaleMoveQueue,
 };
+use crate::fighter::attributes::FighterAttributes;
 use crate::fighter::baked_animation::BakedFighterAnimations;
 use crate::fighter::ecb::FighterPreviousECB;
 use crate::fighter::manifest::FighterManifest;
@@ -47,22 +48,22 @@ macro_rules! fighter_states {
             pub fn name(&self) -> &'static str {
                 match self { $(Self::$variant(_) => <$ty>::NAME),* }
             }
-            pub fn check_interrupt(&self, ctx: &mut FighterStateContext) -> Option<FighterState> {
+            pub fn check_interrupt(&self, ctx: &mut InterruptContext) -> Option<FighterState> {
                 match self { $(Self::$variant(s) => s.check_interrupt(ctx)),* }
             }
 
-            pub fn update(&mut self, ctx: &mut FighterStateContext) {
+            pub fn update(&mut self, ctx: &mut UpdateContext) {
                 match self { $(Self::$variant(s) => s.update(ctx)),* }
             }
-            pub fn on_enter(&mut self, ctx: &mut FighterStateContext) {
+            pub fn on_enter(&mut self, ctx: &mut EnterContext) {
                 match self { $(Self::$variant(s) => s.on_enter(ctx)),* }
             }
 
-            pub fn on_exit(&mut self, ctx: &mut FighterStateContext) {
+            pub fn on_exit(&mut self, ctx: &mut ExitContext) {
                 match self { $(Self::$variant(s) => s.on_exit(ctx)),* }
             }
 
-            pub fn check_collision_interrupt(&mut self, ctx: &mut FighterStateContext) -> Option<FighterState> {
+            pub fn check_collision_interrupt(&mut self, ctx: &mut CollisionContext) -> Option<FighterState> {
                 match self { $(Self::$variant(s) => s.check_collision_interrupt(ctx)),* }
             }
         }
@@ -75,62 +76,109 @@ macro_rules! fighter_states {
 
 pub trait FighterStateImpl: Sized {
     const NAME: &'static str;
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState>;
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState>;
 
-    fn on_enter(&mut self, _state_context: &mut FighterStateContext) {}
-    fn on_exit(&mut self, _state_context: &mut FighterStateContext) {}
+    fn on_enter(&mut self, _state_context: &mut EnterContext) {}
+    fn on_exit(&mut self, _state_context: &mut ExitContext) {}
     fn name(&self) -> String {
         Self::NAME.to_owned()
     }
-    fn update(&mut self, _state_context: &mut FighterStateContext);
+    fn update(&mut self, _state_context: &mut UpdateContext);
 
     fn check_collision_interrupt(
         &mut self,
-        _state_context: &mut FighterStateContext,
+        _state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
         None
     }
 }
 
-pub struct FighterStateContext<'a> {
-    pub translation: &'a mut FighterTranslation,
-    pub prev_translation: &'a mut FighterPreviousTranslation,
+pub struct AnimationStatus {
+    pub frame: u32,
+    pub finished: bool,
+}
+
+pub struct InterruptContext<'a> {
+    pub input: &'a FighterInput,
+    pub facing_direction: &'a mut FighterFacingDirection,
+    pub game_settings: &'a GameSettings,
+    pub fighter_attributes: &'a FighterAttributes,
+    pub animation: AnimationStatus,
+}
+
+impl InterruptContext<'_> {
+    pub fn get_current_animation_frame(&self) -> u32 {
+        self.animation.frame
+    }
+
+    pub fn is_current_animation_finished(&self) -> bool {
+        self.animation.finished
+    }
+}
+
+pub struct EnterContext<'a> {
     pub input: &'a mut FighterInput,
     pub hitboxes: &'a mut FighterHitboxes,
     pub velocity: &'a mut FighterVelocity,
     pub knockback_velocity: &'a mut FighterKnockbackVelocity,
     pub stale_move_queue: &'a mut FighterStaleMoveQueue,
-    pub ecb: &'a mut FighterECB,
-    pub prev_ecb: &'a mut FighterPreviousECB,
     pub facing_direction: &'a mut FighterFacingDirection,
-    pub game_settings: &'a GameSettings,
-    pub stage_collision: &'a StageCollision,
-    pub animations: &'a FighterAnimations,
     pub animation_frame: &'a mut FighterAnimationFrame,
-    pub baked_animations: &'a Assets<BakedFighterAnimations>,
-    pub attack_scripts: &'a Assets<FighterAttackScript>,
-    pub fighter_manifest: &'a FighterManifest,
+    pub fighter_attributes: &'a FighterAttributes,
     pub attack_script_assets: &'a FighterAttackScriptAssets,
 }
 
-impl FighterStateContext<'_> {
+impl EnterContext<'_> {
     pub fn play_animation(&mut self, kind: AnimKind, repeat: bool) {
         self.animation_frame.reset(kind, repeat);
     }
-
-    pub fn get_current_animation_frame(&self) -> u32 {
-        self.animation_frame.frame
 }
 
-    pub fn is_current_animation_finished(&self) -> bool {
-        let anims_data = self
-            .baked_animations
-            .get(&self.animations.baked)
-            .expect("Animation should exist");
-        anims_data
-            .frame_count(self.animation_frame.kind)
-            .expect("Current animation should have baked frames")
-            <= self.animation_frame.frame
+pub struct ExitContext<'a> {
+    pub hitboxes: &'a mut FighterHitboxes,
+}
+
+pub struct UpdateContext<'a> {
+    pub translation: &'a mut FighterTranslation,
+    pub prev_translation: &'a mut FighterPreviousTranslation,
+    pub input: &'a FighterInput,
+    pub hitboxes: &'a mut FighterHitboxes,
+    pub velocity: &'a mut FighterVelocity,
+    pub knockback_velocity: &'a mut FighterKnockbackVelocity,
+    pub game_settings: &'a GameSettings,
+    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,
+}
+
+impl UpdateContext<'_> {
+    pub fn get_current_animation_frame(&self) -> u32 {
+        self.animation_frame
+    }
+}
+
+pub struct CollisionContext<'a> {
+    pub translation: &'a mut FighterTranslation,
+    pub prev_translation: &'a FighterPreviousTranslation,
+    pub velocity: &'a mut FighterVelocity,
+    pub ecb: &'a FighterECB,
+    pub prev_ecb: &'a FighterPreviousECB,
+    pub stage_collision: &'a StageCollision,
+}
+
+impl CollisionContext<'_> {
+    pub fn air_collide_with_stage(
+        &self,
+    ) -> Option<crate::fighter::collision::AirCollisionWithStageResult> {
+        crate::fighter::collision::air_collide_with_stage(
+            self.prev_translation,
+            self.translation,
+            self.prev_ecb,
+            self.ecb,
+            self.stage_collision,
+        )
     }
 }
 
@@ -159,43 +207,105 @@ pub struct FighterFrameQuery {
     pub velocity: &'static mut FighterVelocity,
     pub knockback_velocity: &'static mut FighterKnockbackVelocity,
     pub stale_move_queue: &'static mut FighterStaleMoveQueue,
-    pub ecb: &'static mut FighterECB,
-    pub prev_ecb: &'static mut FighterPreviousECB,
+    pub ecb: &'static FighterECB,
+    pub prev_ecb: &'static FighterPreviousECB,
     pub facing_direction: &'static mut FighterFacingDirection,
     pub animation_frame: &'static mut FighterAnimationFrame,
     pub fighter: &'static Fighter,
 }
 
 impl<'w, 's> FighterFrameQueryItem<'w, 's> {
-    fn context<'a>(
+    fn animation_status(
+        &self,
+        animations: &FighterAnimations,
+        baked_animations: &Assets<BakedFighterAnimations>,
+    ) -> AnimationStatus {
+        let baked = baked_animations
+            .get(&animations.baked)
+            .expect("Animation should exist");
+        let frame = self.animation_frame.frame;
+        let finished = baked
+            .frame_count(self.animation_frame.kind)
+            .expect("Current animation should have baked frames")
+            <= frame;
+        AnimationStatus { frame, finished }
+    }
+
+    fn interrupt_context<'a>(
         &'a mut self,
         game_settings: &'a GameSettings,
-        stage_collision: &'a StageCollision,
         animations: &'a FighterAnimations,
         baked_animations: &'a Assets<BakedFighterAnimations>,
-        attack_scripts: &'a Assets<FighterAttackScript>,
+        attributes: &'a FighterAttributes,
+    ) -> InterruptContext<'a> {
+        let animation = self.animation_status(animations, baked_animations);
+        InterruptContext {
+            input: &self.input,
+            facing_direction: &mut self.facing_direction,
+            game_settings,
+            fighter_attributes: attributes,
+            animation,
+        }
+    }
+
+    fn enter_context<'a>(
+        &'a mut self,
+        attributes: &'a FighterAttributes,
         attack_script_assets: &'a FighterAttackScriptAssets,
-        manifest: &'a FighterManifest,
-    ) -> FighterStateContext<'a> {
-        FighterStateContext {
-            translation: &mut self.translation,
-            prev_translation: &mut self.prev_translation,
+    ) -> EnterContext<'a> {
+        EnterContext {
             input: &mut self.input,
             hitboxes: &mut self.hitboxes,
             velocity: &mut self.velocity,
             knockback_velocity: &mut self.knockback_velocity,
             stale_move_queue: &mut self.stale_move_queue,
-            ecb: &mut self.ecb,
-            prev_ecb: &mut self.prev_ecb,
             facing_direction: &mut self.facing_direction,
-            game_settings,
-            stage_collision,
-            animations,
             animation_frame: &mut self.animation_frame,
-            baked_animations,
+            fighter_attributes: attributes,
+            attack_script_assets,
+        }
+    }
+
+    fn exit_context(&mut self) -> ExitContext<'_> {
+        ExitContext {
+            hitboxes: &mut self.hitboxes,
+        }
+    }
+
+    fn update_context<'a>(
+        &'a mut self,
+        game_settings: &'a GameSettings,
+        attributes: &'a FighterAttributes,
+        attack_scripts: &'a Assets<FighterAttackScript>,
+        attack_script_assets: &'a FighterAttackScriptAssets,
+    ) -> UpdateContext<'a> {
+        UpdateContext {
+            translation: &mut self.translation,
+            prev_translation: &mut self.prev_translation,
+            input: &self.input,
+            hitboxes: &mut self.hitboxes,
+            velocity: &mut self.velocity,
+            knockback_velocity: &mut self.knockback_velocity,
+            game_settings,
+            animation_frame: self.animation_frame.frame,
+            fighter_attributes: attributes,
             attack_scripts,
             attack_script_assets,
-            fighter_manifest: manifest,
+            facing_direction: &self.facing_direction
+        }
+    }
+
+    fn collision_context<'a>(
+        &'a mut self,
+        stage_collision: &'a StageCollision,
+    ) -> CollisionContext<'a> {
+        CollisionContext {
+            translation: &mut self.translation,
+            prev_translation: &self.prev_translation,
+            velocity: &mut self.velocity,
+            ecb: &self.ecb,
+            prev_ecb: &self.prev_ecb,
+            stage_collision,
         }
     }
 }
@@ -214,9 +324,7 @@ pub struct StatefulFighterQuery {
 
 pub fn state_update_system(
     mut query: Query<StatefulFighterQuery>,
-    stage_collision: Res<StageCollision>,
     game_settings: Res<GameSettings>,
-    baked_animations: Res<Assets<BakedFighterAnimations>>,
     attack_scripts: Res<Assets<FighterAttackScript>>,
     manifests: Res<Assets<FighterManifest>>,
 ) {
@@ -224,7 +332,6 @@ pub fn state_update_system(
         let StatefulFighterQueryItem {
             mut state,
             mut frame,
-            animations,
             hitstop,
             ..
         } = fighter;
@@ -233,16 +340,14 @@ pub fn state_update_system(
             continue;
         }
 
-        let mut update_ctx = frame.context(
+        let manifest = manifests
+            .get(&fighter.fighter.manifest)
+            .expect("Fighter manifest should be valid");
+        let mut update_ctx = frame.update_context(
             &game_settings,
-            &stage_collision,
-            animations,
-            &baked_animations,
+            &manifest.attributes,
             &attack_scripts,
             &fighter.attack_script_assets,
-            &manifests
-                .get(&(fighter.fighter.manifest))
-                .expect("Fighter manifest should be valid"),
         );
         state.update(&mut update_ctx);
     }
@@ -251,24 +356,24 @@ pub fn state_update_system(
 fn transition_state(
     current: &mut FighterState,
     mut next: FighterState,
-    ctx: &mut FighterStateContext,
+    frame: &mut FighterFrameQueryItem,
+    attributes: &FighterAttributes,
+    attack_script_assets: &FighterAttackScriptAssets,
 ) {
     let old_name = current.name();
     let new_name = next.name();
 
-    current.on_exit(ctx);
-    next.on_enter(ctx);
+    current.on_exit(&mut frame.exit_context());
+    next.on_enter(&mut frame.enter_context(attributes, attack_script_assets));
     *current = next;
     info!("{} -> {}", old_name, new_name);
 }
 
 pub fn state_interrupt_system(
     mut query: Query<StatefulFighterQuery>,
-    stage_collision: Res<StageCollision>,
     game_settings: Res<GameSettings>,
     baked_animations: Res<Assets<BakedFighterAnimations>>,
     fighter_manifests: Res<Assets<FighterManifest>>,
-    attack_scripts: Res<Assets<FighterAttackScript>>,
 ) {
     for fighter in &mut query {
         let StatefulFighterQueryItem {
@@ -280,17 +385,9 @@ pub fn state_interrupt_system(
             mut pending_hit_reaction,
             mut hitstop,
         } = fighter;
-        let mut state_context = frame.context(
-            &game_settings,
-            &stage_collision,
-            animations,
-            &baked_animations,
-            &attack_scripts,
-            attack_script_assets,
-            fighter_manifests
+        let manifest = fighter_manifests
             .get(&fighter.manifest)
-                .expect("Fighter manifest should be valid"),
-        );
+            .expect("Fighter manifest should be valid");
 
         let new_state = if let Some(reaction) = pending_hit_reaction.take() {
             hitstop.remaining_frames = *reaction.hitstop_frames;
@@ -322,11 +419,22 @@ pub fn state_interrupt_system(
         } else if hitstop.remaining_frames > 0 {
             None
         } else {
-            state.check_interrupt(&mut state_context)
+            state.check_interrupt(&mut frame.interrupt_context(
+                &game_settings,
+                animations,
+                &baked_animations,
+                &manifest.attributes,
+            ))
         };
 
         if let Some(new_state) = new_state {
-            transition_state(&mut state, new_state, &mut state_context);
+            transition_state(
+                &mut state,
+                new_state,
+                &mut frame,
+                &manifest.attributes,
+                attack_script_assets,
+            );
         };
     }
 }
@@ -334,39 +442,34 @@ pub fn state_interrupt_system(
 pub fn state_collision_interrupt_system(
     mut query: Query<StatefulFighterQuery>,
     stage_collision: Res<StageCollision>,
-    game_settings: Res<GameSettings>,
-    baked_animations: Res<Assets<BakedFighterAnimations>>,
     fighter_manifests: Res<Assets<FighterManifest>>,
-    attack_scripts: Res<Assets<FighterAttackScript>>,
 ) {
     for fighter in &mut query {
         let StatefulFighterQueryItem {
             mut state,
             mut frame,
-            animations,
             fighter,
             attack_script_assets,
             hitstop,
             ..
         } = fighter;
-        let mut state_context = frame.context(
-            &game_settings,
-            &stage_collision,
-            animations,
-            &baked_animations,
-            &attack_scripts,
-            &attack_script_assets,
-            fighter_manifests
-                .get(&fighter.manifest)
-                .expect("Fighter manifest should be valid"),
-        );
-
         if hitstop.remaining_frames > 0 {
             continue;
         }
 
-        if let Some(new_state) = state.check_collision_interrupt(&mut state_context) {
-            transition_state(&mut state, new_state, &mut state_context);
+        let manifest = fighter_manifests
+            .get(&fighter.manifest)
+            .expect("Fighter manifest should be valid");
+        let new_state =
+            state.check_collision_interrupt(&mut frame.collision_context(&stage_collision));
+        if let Some(new_state) = new_state {
+            transition_state(
+                &mut state,
+                new_state,
+                &mut frame,
+                &manifest.attributes,
+                &attack_script_assets,
+            );
         }
     }
 }

src/fighter/state/run.rs

@@ -1,11 +1,12 @@
 use bevy::prelude::*;
 
-use super::{FighterStateContext, FighterStateImpl, ground, wait, walk};
+use super::{
+    CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext, ground,
+    wait, walk,
+};
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::FighterState;
-use crate::fighter::state::fall::FallState;
-use crate::fighter::state::ground::{GroundedMotionResult, GroundedStateCommon};
-use crate::math::int::FGi32;
+use crate::fighter::state::ground::GroundedStateCommon;
 
 #[derive(Component, Debug, Clone, Hash)]
 pub struct RunState {
@@ -14,7 +15,7 @@ pub struct RunState {
 
 impl FighterStateImpl for RunState {
     const NAME: &'static str = "Run";
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if let Some(state) =
             ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
         {
@@ -32,21 +33,20 @@ impl FighterStateImpl for RunState {
         }
     }
 
-    fn on_enter(&mut self, state_context: &mut super::FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::Run, true);
     }
 
-    fn update(&mut self, state_context: &mut super::FighterStateContext) {
+    fn update(&mut self, state_context: &mut UpdateContext) {
         let last_frame = state_context.input.get_last_frame();
         let (accel, target_vel) = state_context
-            .fighter_manifest
-            .attributes
-            .get_accel_and_target_dashrun(&last_frame, FGi32::ONE);
+            .fighter_attributes
+            .get_accel_and_target_dashrun(&last_frame, state_context.facing_direction.to_sign());
         let accel = ground::compute_ground_accel(
             accel,
             target_vel,
             state_context.velocity.x,
-            &state_context.fighter_manifest.attributes,
+            state_context.fighter_attributes,
             state_context.game_settings,
         );
         state_context.velocity.x += accel;
@@ -60,20 +60,14 @@ impl FighterStateImpl for RunState {
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, false)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.grounded_common, true)
     }
 }
 
 pub fn check_input(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_state_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();

src/fighter/state/turn.rs

@@ -1,7 +1,6 @@
-use super::{FighterStateContext, FighterStateImpl};
+use super::{CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext};
 use crate::fighter::animation::AnimKind;
-use crate::fighter::state::fall::FallState;
-use crate::fighter::state::ground::{self, GroundedMotionResult, GroundedStateCommon};
+use crate::fighter::state::ground::{self, GroundedStateCommon};
 use crate::fighter::state::{FighterState, dash, jump, wait, walk};
 use crate::input::FighterCommands;
 
@@ -12,7 +11,7 @@ pub struct TurnState {
 
 impl FighterStateImpl for TurnState {
     const NAME: &'static str = "Turn";
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         // State chain that results in the turn completing
         if state_context.get_current_animation_frame()
             <= state_context
@@ -42,51 +41,25 @@ impl FighterStateImpl for TurnState {
         }
     }
 
-    fn on_enter(&mut self, state_context: &mut super::FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::Turn, false);
         *state_context.facing_direction = state_context.facing_direction.reverse();
     }
 
-    fn update(&mut self, state_context: &mut super::FighterStateContext) {
-        let friction = if state_context.velocity.x.abs()
-            > state_context.fighter_manifest.attributes.max_walk_vel
-        {
-            state_context.fighter_manifest.attributes.ground_friction
-                * state_context
-                    .game_settings
-                    .fighter_common
-                    .ground_friction_over_walk_speed_multiplier
-        } else {
-            state_context.fighter_manifest.attributes.ground_friction
-        };
-
-        let ground_velocity = state_context.velocity.x;
-
-        state_context.velocity.x += ground::apply_grounded_friction(friction, ground_velocity);
-
-        ground::apply_grounded_motion(
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        ground::update_friction_motion(state_context);
     }
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, false)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
     }
 }
 
 pub fn check_input(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     grounded_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();

src/fighter/state/wait.rs

@@ -1,8 +1,9 @@
-use super::{FighterStateContext, FighterStateImpl, ground};
+use super::{
+    CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext, ground,
+};
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::FighterState;
-use crate::fighter::state::fall::FallState;
-use crate::fighter::state::ground::{GroundedMotionResult, GroundedStateCommon};
+use crate::fighter::state::ground::GroundedStateCommon;
 
 #[derive(Debug, Clone, Hash)]
 pub struct WaitState {
@@ -11,7 +12,7 @@ pub struct WaitState {
 
 impl FighterStateImpl for WaitState {
     const NAME: &'static str = "Wait";
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if let Some(state) =
             ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
         {
@@ -31,50 +32,24 @@ impl FighterStateImpl for WaitState {
         }
     }
 
-    fn on_enter(&mut self, state_context: &mut super::FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::Wait, true);
     }
 
-    fn update(&mut self, state_context: &mut super::FighterStateContext) {
-        let friction = if state_context.velocity.x.abs()
-            > state_context.fighter_manifest.attributes.max_walk_vel
-        {
-            state_context.fighter_manifest.attributes.ground_friction
-                * state_context
-                    .game_settings
-                    .fighter_common
-                    .ground_friction_over_walk_speed_multiplier
-        } else {
-            state_context.fighter_manifest.attributes.ground_friction
-        };
-
-        let ground_velocity = state_context.velocity.x;
-
-        state_context.velocity.x += ground::apply_grounded_friction(friction, ground_velocity);
-
-        ground::apply_grounded_motion(
-            state_context.velocity,
-            state_context.translation,
-            state_context.prev_translation,
-        );
+    fn update(&mut self, state_context: &mut UpdateContext) {
+        ground::update_friction_motion(state_context);
     }
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, false)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
     }
 }
 
 pub fn check_input(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_state_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();

src/fighter/state/walk.rs

@@ -1,8 +1,10 @@
-use super::{FighterStateContext, FighterStateImpl, dash, ground, wait};
+use super::{
+    CollisionContext, EnterContext, FighterStateImpl, InterruptContext, UpdateContext, dash,
+    ground, wait,
+};
 use crate::fighter::animation::AnimKind;
 use crate::fighter::state::FighterState;
-use crate::fighter::state::fall::FallState;
-use crate::fighter::state::ground::{GroundedMotionResult, GroundedStateCommon};
+use crate::fighter::state::ground::GroundedStateCommon;
 
 #[derive(Debug, Clone, Hash)]
 pub struct WalkState {
@@ -11,7 +13,7 @@ pub struct WalkState {
 
 impl FighterStateImpl for WalkState {
     const NAME: &'static str = "Walk";
-    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
+    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
         if let Some(state) =
             ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
         {
@@ -21,22 +23,21 @@ impl FighterStateImpl for WalkState {
             .or_else(|| dash::check_input(state_context, &self.grounded_common))
     }
 
-    fn on_enter(&mut self, state_context: &mut FighterStateContext) {
+    fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::Walk, true);
     }
 
-    fn update(&mut self, state_context: &mut FighterStateContext) {
+    fn update(&mut self, state_context: &mut UpdateContext) {
         let last_frame = state_context.input.get_last_frame();
         let (accel, target_vel) = state_context
-            .fighter_manifest
-            .attributes
+            .fighter_attributes
             .get_accel_and_target_walk(&last_frame);
 
         let accel = ground::compute_ground_accel(
             accel,
             target_vel,
             state_context.velocity.x,
-            &state_context.fighter_manifest.attributes,
+            state_context.fighter_attributes,
             &state_context.game_settings,
         );
 
@@ -51,20 +52,14 @@ impl FighterStateImpl for WalkState {
 
     fn check_collision_interrupt(
         &mut self,
-        state_context: &mut FighterStateContext,
+        state_context: &mut CollisionContext,
     ) -> Option<FighterState> {
-        if let GroundedMotionResult::InAir =
-            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, false)
-        {
-            Some(FighterState::Fall(FallState))
-        } else {
-            None
-        }
+        ground::collision_interrupt(state_context, &mut self.grounded_common, false)
     }
 }
 
 pub fn check_input(
-    state_context: &FighterStateContext,
+    state_context: &InterruptContext,
     ground_state_common: &GroundedStateCommon,
 ) -> Option<FighterState> {
     let input_frame = state_context.input.get_last_frame();