Tighten hold buffer lifetime semantics

src/fighter/state/air_attack.rs

@@ -45,6 +45,9 @@ impl FighterStateImpl for AirAttackState {
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context
+            .input
+            .consume_command(crate::input::FighterCommands::Attack);
         state_context.play_animation(self.attack_kind.get_animation(), false);
         let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
         state_context.hitboxes.0 = Some(crate::fighter::FighterActiveAttack {

src/fighter/state/air_dodge.rs

@@ -1,13 +1,17 @@
 use crate::{
     fighter::{
-        FighterInvulnerabilityState, animation::AnimKind, state::{
+        FighterInvulnerabilityState,
+        animation::AnimKind,
+        state::{
             CollisionContext, EnterContext, FighterState, FighterStateImpl, InterruptContext,
             UpdateContext,
             air::{self, AirborneStateCommon},
             fall::FallState,
             land::LandingType,
         },
-    }, input, math::vec::FGVec2,
+    },
+    input,
+    math::vec::FGVec2,
 };
 
 #[derive(Debug, Clone, Hash)]
@@ -29,8 +33,13 @@ impl FighterStateImpl for AirDodgeState {
     }
 
     fn update(&mut self, state_context: &mut UpdateContext) {
-        let airdodge_intangible_end = state_context.fighter_attributes.air_dodge_intangible_start + state_context.fighter_attributes.air_dodge_intangible_duration;
-        if state_context.animation_frame == state_context.fighter_attributes.air_dodge_intangible_start {
+        let airdodge_intangible_end = state_context.fighter_attributes.air_dodge_intangible_start
+            + state_context
+                .fighter_attributes
+                .air_dodge_intangible_duration;
+        if state_context.animation_frame
+            == state_context.fighter_attributes.air_dodge_intangible_start
+        {
             *state_context.vulnerability = FighterInvulnerabilityState::Intangible;
         } else if state_context.animation_frame >= airdodge_intangible_end {
             *state_context.vulnerability = FighterInvulnerabilityState::Vulnerable;
@@ -54,6 +63,13 @@ impl FighterStateImpl for AirDodgeState {
     fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::AirDodge, false);
 
+        state_context
+            .input
+            .clear_command(input::FighterCommands::Shield);
+        state_context
+            .input
+            .clear_command(input::FighterCommands::GuardHold);
+
         state_context.velocity.0 =
             self.direction * state_context.fighter_attributes.air_dodge_velocity;
     }
@@ -79,7 +95,14 @@ pub fn check_input(state_context: &InterruptContext) -> Option<FighterState> {
     state_context
         .input
         .has_command(input::FighterCommands::Shield)
-        .then(|| {
+        .then_some(())
+        .or_else(|| {
+            state_context
+                .input
+                .has_command(input::FighterCommands::GuardHold)
+                .then_some(())
+        })
+        .map(|_| {
             FighterState::AirDodge(AirDodgeState {
                 direction: state_context
                     .input

src/fighter/state/ground_attack.rs

@@ -42,6 +42,9 @@ impl FighterStateImpl for GroundAttackState {
     }
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
+        state_context
+            .input
+            .consume_command(crate::input::FighterCommands::Attack);
         state_context.play_animation(self.attack_kind.get_animation(), false);
         let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
         state_context.hitboxes.0 = Some(crate::fighter::FighterActiveAttack {

src/fighter/state/jump.rs

@@ -11,7 +11,7 @@ use crate::{
             ground,
         },
     },
-    input::FighterCommands,
+    input::{DigitalAction, FighterCommands},
     math::{int::FGi32, vec::FGVec2},
 };
 #[derive(Debug, Hash, Clone, Copy)]
@@ -68,8 +68,18 @@ impl FighterStateImpl for JumpSquatState {
                 direction: wavedash_dir.normalize_or_zero(),
             }))
         } else if self.duration_counter >= state_context.fighter_attributes.jumpsquat_duration {
-            info!("Jump {}", state_context.input.get_last_frame().jump);
-            let jump_type = if state_context.input.get_last_frame().jump {
+            info!(
+                "Jump {}",
+                state_context
+                    .input
+                    .get_last_frame()
+                    .is_held(DigitalAction::Jump)
+            );
+            let jump_type = if state_context
+                .input
+                .get_last_frame()
+                .is_held(DigitalAction::Jump)
+            {
                 JumpType::LongJump
             } else {
                 JumpType::ShortHop
@@ -97,9 +107,18 @@ impl FighterStateImpl for JumpSquatState {
 
     fn on_enter(&mut self, state_context: &mut EnterContext) {
         state_context.play_animation(AnimKind::JumpSquat, false);
+        // Preserve buffered inputs while jump squat makes the transition
+        // temporarily unavailable, matching Ultimate/HDR-style hold input.
+        state_context.input.enable_hold_all(10);
         state_context.input.clear_command(FighterCommands::Jump);
     }
 
+    fn on_exit(&mut self, state_context: &mut crate::fighter::state::ExitContext) {
+        // The hold policy is state-scoped and must never leak into the next
+        // state. Command lifetime itself remains independent of this policy.
+        state_context.input.disable_hold_all();
+    }
+
     fn is_visually_grounded<'a>(&'a self) -> bool {
         true
     }

src/fighter/state/mod.rs

@@ -18,7 +18,10 @@ use crate::fighter::state::hitstun::HitstunState;
 use crate::fighter::surface::EcbLockPolicy;
 use crate::fighter::visual::FighterAnimations;
 use crate::fighter::{
-    Fighter, FighterDamage, FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop, FighterHitstopShake, FighterHitstopShakeKind, FighterHitstopShakeRole, FighterInvulnerabilityState, FighterPendingRespawn, FighterPresentationSnap, FighterPreviousTranslation, FighterSurfaceState, FighterTranslation, FighterVelocity,
+    Fighter, FighterDamage, FighterECB, FighterFacingDirection, FighterHitboxes, FighterHitstop,
+    FighterHitstopShake, FighterHitstopShakeKind, FighterHitstopShakeRole,
+    FighterInvulnerabilityState, FighterPendingRespawn, FighterPresentationSnap,
+    FighterPreviousTranslation, FighterSurfaceState, FighterTranslation, FighterVelocity,
 };
 use crate::game_settings::GameSettings;
 use crate::input::FighterInput;
@@ -32,6 +35,7 @@ use crate::stage::line::StageCollision;
 use crate::stage::manifest::{StageManifest, StageManifestRegistry};
 
 pub mod air;
+pub mod air_attack;
 pub mod air_dodge;
 pub mod angel;
 pub mod crouch;
@@ -47,7 +51,6 @@ pub mod run;
 pub mod turn;
 pub mod wait;
 pub mod walk;
-pub mod air_attack;
 
 #[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
 pub enum SurfacePolicy {
@@ -170,6 +173,7 @@ impl EnterContext<'_> {
 }
 
 pub struct ExitContext<'a> {
+    pub input: &'a mut FighterInput,
     pub hitboxes: &'a mut FighterHitboxes,
     pub surface: &'a mut FighterSurfaceState,
     pub vulnerability: &'a mut FighterInvulnerabilityState,
@@ -306,7 +310,7 @@ impl<'w, 's> FighterFrameQueryItem<'w, 's> {
             animation,
             surface: &self.surface,
             stage_collision,
-            attack_script_assets: attack_script_assets
+            attack_script_assets: attack_script_assets,
         }
     }
 
@@ -333,6 +337,7 @@ impl<'w, 's> FighterFrameQueryItem<'w, 's> {
 
     fn exit_context(&mut self) -> ExitContext<'_> {
         ExitContext {
+            input: &mut self.input,
             hitboxes: &mut self.hitboxes,
             surface: &mut self.surface,
             vulnerability: &mut self.vulnerability,
@@ -540,7 +545,7 @@ pub fn state_interrupt_system(
                 &baked_animations,
                 &manifest.attributes,
                 &stage_collision,
-                attack_script_assets
+                attack_script_assets,
             ))
         };
 

src/input/buffer.rs

@@ -1,8 +1,9 @@
-//! Per-fighter input state: the current and previous frame, plus the buffered
-//! commands (smash inputs and friends) that states query when deciding whether
-//! to interrupt.
-
-use std::ops::{Index, IndexMut};
+//! Rollback-safe input history and command buffering.
+//!
+//! Raw mapped bindings, button edges, and command lifetimes are deliberately
+//! separate. This preserves combinations such as pressing a second shield
+//! binding while the first one is held, while still allowing a command to
+//! survive after its source button is released.
 
 use bevy::prelude::*;
 use bevy_ggrs::{PlayerInputs, Rollback};
@@ -12,14 +13,15 @@ use strum_macros::EnumIter;
 use crate::fighter::FighterFacingDirection;
 use crate::fighter::attack::AttackKind;
 use crate::game_settings::GameSettings;
-use crate::input::FighterInputFrame;
+use crate::input::{DigitalAction, FighterInputFrame};
 use crate::netcode::GGRSCfg;
 use crate::player::Player;
 
-#[derive(Clone, Copy, EnumIter, Debug)]
+#[derive(Clone, Copy, EnumIter, Debug, PartialEq, Eq, Hash)]
 pub enum FighterCommands {
     Jump,
     Shield,
+    GuardHold,
     Attack,
     SmashMoveUp,
     SmashMoveDown,
@@ -27,7 +29,31 @@ pub enum FighterCommands {
     SmashMoveRight,
 }
 
-#[derive(Default, Clone, Hash, Copy)]
+pub(crate) fn second_binding_pressed(
+    current: crate::input::ActionBindingMask,
+    previous: crate::input::ActionBindingMask,
+) -> bool {
+    current.count() >= 2 && current.pressed_since(previous).0 != 0
+}
+
+impl FighterCommands {
+    pub const COUNT: usize = 8;
+
+    pub const fn index(self) -> usize {
+        match self {
+            Self::Jump => 0,
+            Self::Shield => 1,
+            Self::GuardHold => 2,
+            Self::Attack => 3,
+            Self::SmashMoveUp => 4,
+            Self::SmashMoveDown => 5,
+            Self::SmashMoveLeft => 6,
+            Self::SmashMoveRight => 7,
+        }
+    }
+}
+
+#[derive(Default, Clone, Hash, Copy, Debug)]
 pub enum FighterAttackCommandType {
     #[default]
     Neutral,
@@ -44,86 +70,140 @@ pub enum FighterAttackCommandType {
 impl FighterAttackCommandType {
     pub fn to_attack_kind_grounded(&self) -> AttackKind {
         match self {
-            FighterAttackCommandType::Neutral => AttackKind::Jab,
-            FighterAttackCommandType::SmashAttackUp => AttackKind::UpSmash,
-            FighterAttackCommandType::SmashAttackDown => AttackKind::DownSmash,
-            FighterAttackCommandType::SmashAttackLeft => AttackKind::ForwardSmash,
-            FighterAttackCommandType::SmashAttackRight => AttackKind::ForwardSmash,
-            FighterAttackCommandType::TiltAttackUp => AttackKind::UpTilt,
-            FighterAttackCommandType::TiltAttackDown => AttackKind::DownTilt,
-            FighterAttackCommandType::TiltAttackLeft => AttackKind::ForwardTilt,
-            FighterAttackCommandType::TiltAttackRight => AttackKind::ForwardTilt,
+            Self::Neutral => AttackKind::Jab,
+            Self::SmashAttackUp => AttackKind::UpSmash,
+            Self::SmashAttackDown => AttackKind::DownSmash,
+            Self::SmashAttackLeft | Self::SmashAttackRight => AttackKind::ForwardSmash,
+            Self::TiltAttackUp => AttackKind::UpTilt,
+            Self::TiltAttackDown => AttackKind::DownTilt,
+            Self::TiltAttackLeft | Self::TiltAttackRight => AttackKind::ForwardTilt,
         }
     }
+
     pub fn to_attack_kind_airborne(&self, facing_direction: &FighterFacingDirection) -> AttackKind {
         match self {
-            FighterAttackCommandType::Neutral => AttackKind::NeutralAir,
-            FighterAttackCommandType::SmashAttackUp | FighterAttackCommandType::TiltAttackUp => AttackKind::UpAir,
-            FighterAttackCommandType::SmashAttackDown | FighterAttackCommandType::TiltAttackDown => AttackKind::DownAir,
-            
-            FighterAttackCommandType::SmashAttackLeft | FighterAttackCommandType::TiltAttackLeft => {
-                match facing_direction {
+            Self::Neutral => AttackKind::NeutralAir,
+            Self::SmashAttackUp | Self::TiltAttackUp => AttackKind::UpAir,
+            Self::SmashAttackDown | Self::TiltAttackDown => AttackKind::DownAir,
+            Self::SmashAttackLeft | Self::TiltAttackLeft => match facing_direction {
                 FighterFacingDirection::Left => AttackKind::ForwardAir,
                 FighterFacingDirection::Right => AttackKind::BackAir,
-                }
             },
-            FighterAttackCommandType::SmashAttackRight | FighterAttackCommandType::TiltAttackRight => {
-                match facing_direction {
+            Self::SmashAttackRight | Self::TiltAttackRight => match facing_direction {
                 FighterFacingDirection::Left => AttackKind::BackAir,
                 FighterFacingDirection::Right => AttackKind::ForwardAir,
-                }
             },
         }
     }
 }
 
-/// Frames of life remaining for each buffered command. Indexed by
-/// [`FighterCommands`] so adding a command is a two-line change here.
-#[derive(Default, Clone, Copy, Hash)]
-pub struct FighterCommandLifetimes {
-    smash_move_left: u8,
-    smash_move_right: u8,
-    smash_move_down: u8,
-    smash_move_up: u8,
-    jump: u8,
-    shield: u8,
-    attack: u8,
+#[derive(Clone, Copy, Debug, Hash)]
+struct CommandSlot {
+    lifetime: u8,
+    age: u16,
+    hold_remaining: HoldLimit,
+    consumed: bool,
 }
 
-impl Index<FighterCommands> for FighterCommandLifetimes {
-    type Output = u8;
-
-    fn index(&self, command: FighterCommands) -> &Self::Output {
-        match command {
-            FighterCommands::SmashMoveLeft => &self.smash_move_left,
-            FighterCommands::SmashMoveRight => &self.smash_move_right,
-            FighterCommands::SmashMoveDown => &self.smash_move_down,
-            FighterCommands::SmashMoveUp => &self.smash_move_up,
-            FighterCommands::Jump => &self.jump,
-            FighterCommands::Shield => &self.shield,
-            FighterCommands::Attack => &self.attack,
+impl Default for CommandSlot {
+    fn default() -> Self {
+        Self {
+            lifetime: 0,
+            age: 0,
+            hold_remaining: HoldLimit::Disabled,
+            consumed: false,
         }
     }
 }
 
-impl IndexMut<FighterCommands> for FighterCommandLifetimes {
-    fn index_mut(&mut self, command: FighterCommands) -> &mut Self::Output {
-        match command {
-            FighterCommands::SmashMoveLeft => &mut self.smash_move_left,
-            FighterCommands::SmashMoveRight => &mut self.smash_move_right,
-            FighterCommands::SmashMoveDown => &mut self.smash_move_down,
-            FighterCommands::SmashMoveUp => &mut self.smash_move_up,
-            FighterCommands::Jump => &mut self.jump,
-            FighterCommands::Shield => &mut self.shield,
-            FighterCommands::Attack => &mut self.attack,
+#[derive(Clone, Copy, Debug, Default, Hash, PartialEq, Eq)]
+enum HoldLimit {
+    #[default]
+    Disabled,
+    Frames(u16),
+    Infinite,
+}
+
+#[derive(Clone, Copy, Debug, Default, Hash, PartialEq, Eq)]
+enum HoldOverride {
+    #[default]
+    Inherit,
+    Disabled,
+    Frames(u16),
+    Infinite,
+}
+
+impl HoldOverride {
+    fn from_max_frames(max_frames: u16) -> Self {
+        if max_frames == 0 {
+            Self::Infinite
+        } else {
+            Self::Frames(max_frames)
         }
     }
 }
 
-#[derive(Component, Default, Clone, Copy, Hash)]
+impl HoldLimit {
+    fn from_max_frames(max_frames: u16) -> Self {
+        if max_frames == 0 {
+            Self::Infinite
+        } else {
+            Self::Frames(max_frames)
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Hash)]
+struct ButtonHistory {
+    trigger_age: u16,
+    release_age: u16,
+    held_frames: u16,
+    secondary_trigger_age: u16,
+}
+
+impl Default for ButtonHistory {
+    fn default() -> Self {
+        Self {
+            trigger_age: u16::MAX,
+            release_age: u16::MAX,
+            held_frames: 0,
+            secondary_trigger_age: u16::MAX,
+        }
+    }
+}
+
+impl ButtonHistory {
+    fn update(&mut self, current: u16, previous: u16) {
+        let pressed = current & !previous;
+        let released = previous & !current;
+        self.trigger_age = self.trigger_age.saturating_add(1);
+        self.release_age = self.release_age.saturating_add(1);
+        self.secondary_trigger_age = self.secondary_trigger_age.saturating_add(1);
+        if pressed != 0 {
+            self.trigger_age = 0;
+        }
+        if released != 0 {
+            self.release_age = 0;
+        }
+        if current != 0 {
+            self.held_frames = self.held_frames.saturating_add(1);
+        } else {
+            self.held_frames = 0;
+        }
+        if current.count_ones() >= 2 && (pressed != 0 || previous.count_ones() < 2) {
+            self.secondary_trigger_age = 0;
+        }
+    }
+}
+
+/// Per-fighter input state. Every field is deterministic rollback state.
+#[derive(Component, Clone, Copy, Hash)]
 #[require(Rollback)]
 pub struct FighterInput {
-    command_lifetimes: FighterCommandLifetimes,
+    command_slots: [CommandSlot; FighterCommands::COUNT],
+    hold_limits: [HoldOverride; FighterCommands::COUNT],
+    hold_all: HoldLimit,
+    button_history: [ButtonHistory; 3],
     prev_frame: FighterInputFrame,
     current_frame: FighterInputFrame,
     frames_in_x_flick_deadzone: u8,
@@ -131,6 +211,22 @@ pub struct FighterInput {
     attack_command: FighterAttackCommandType,
 }
 
+impl Default for FighterInput {
+    fn default() -> Self {
+        Self {
+            command_slots: [CommandSlot::default(); FighterCommands::COUNT],
+            hold_limits: [HoldOverride::default(); FighterCommands::COUNT],
+            hold_all: HoldLimit::default(),
+            button_history: [ButtonHistory::default(); 3],
+            prev_frame: FighterInputFrame::default(),
+            current_frame: FighterInputFrame::default(),
+            frames_in_x_flick_deadzone: 0xFE,
+            frames_in_y_flick_deadzone: 0xFE,
+            attack_command: FighterAttackCommandType::Neutral,
+        }
+    }
+}
+
 impl FighterInput {
     pub fn get_last_frame(&self) -> FighterInputFrame {
         self.current_frame
@@ -142,40 +238,190 @@ impl FighterInput {
     }
 
     pub fn clear_buffer(&mut self) {
-        self.command_lifetimes = FighterCommandLifetimes::default()
+        self.command_slots = [CommandSlot::default(); FighterCommands::COUNT];
     }
 
     pub fn clear_command(&mut self, command: FighterCommands) {
-        self.command_lifetimes[command] = 0;
+        let slot = &mut self.command_slots[command.index()];
+        slot.lifetime = 0;
+        slot.hold_remaining = HoldLimit::Disabled;
+        slot.consumed = true;
+    }
+
+    pub fn consume_command(&mut self, command: FighterCommands) -> bool {
+        if self.has_command(command) {
+            self.clear_command(command);
+            true
+        } else {
+            false
+        }
     }
 
     pub fn set_lifetime(&mut self, command: FighterCommands, lifetime: u8) {
-        self.command_lifetimes[command] = lifetime;
+        let slot = &mut self.command_slots[command.index()];
+        slot.lifetime = lifetime;
+        slot.age = 0;
+        slot.hold_remaining = HoldLimit::Disabled;
+        slot.consumed = false;
+        self.latch_if_hold_enabled(command);
     }
 
     pub fn has_command(&self, command: FighterCommands) -> bool {
-        self.command_lifetimes[command] > 0
+        self.command_slots[command.index()].lifetime > 0
     }
 
     pub fn reduce_command_lifetime(&mut self, command: FighterCommands) {
-        self.command_lifetimes[command] = self.command_lifetimes[command].saturating_sub(1);
+        self.command_slots[command.index()].lifetime = self.command_slots[command.index()]
+            .lifetime
+            .saturating_sub(1);
+    }
+
+    pub fn enable_hold_all(&mut self, max_frames: u16) {
+        self.hold_all = HoldLimit::from_max_frames(max_frames);
+        self.latch_active_commands();
+    }
+
+    /// Stops enrolling commands in the global hold buffer. Commands already
+    /// latched retain their remaining lifetime so they can cross a state
+    /// boundary, such as jump squat into the first airborne frame.
+    pub fn disable_hold_all(&mut self) {
+        self.hold_all = HoldLimit::Disabled;
+    }
+
+    /// Stops global enrollment and immediately cancels every latched command.
+    pub fn cancel_hold_all(&mut self) {
+        self.disable_hold_all();
+        for slot in &mut self.command_slots {
+            slot.hold_remaining = HoldLimit::Disabled;
+        }
+    }
+
+    pub fn enable_hold(&mut self, command: FighterCommands, max_frames: u16) {
+        self.hold_limits[command.index()] = HoldOverride::from_max_frames(max_frames);
+        if self.has_command(command) {
+            self.latch_if_hold_enabled(command);
+        }
+    }
+
+    /// Explicitly prevents this command from using either command-specific or
+    /// global hold buffering, while preserving an existing latch.
+    pub fn disable_hold(&mut self, command: FighterCommands) {
+        self.hold_limits[command.index()] = HoldOverride::Disabled;
+    }
+
+    /// Removes the command-specific policy so this command inherits the
+    /// global policy again.
+    pub fn reset_hold_override(&mut self, command: FighterCommands) {
+        self.hold_limits[command.index()] = HoldOverride::Inherit;
+    }
+
+    /// Stops enrollment and immediately cancels this command's hold lifetime.
+    pub fn cancel_hold(&mut self, command: FighterCommands) {
+        self.disable_hold(command);
+        self.command_slots[command.index()].hold_remaining = HoldLimit::Disabled;
+    }
+
+    fn latch_if_hold_enabled(&mut self, command: FighterCommands) {
+        let limit = self.hold_limit(command);
+        let slot = &mut self.command_slots[command.index()];
+        slot.hold_remaining = match limit {
+            HoldLimit::Disabled => return,
+            HoldLimit::Infinite => HoldLimit::Infinite,
+            // The limit includes tap-buffer frames already elapsed.
+            HoldLimit::Frames(max_frames) => {
+                let remaining = max_frames.saturating_sub(slot.age);
+                if remaining == 0 {
+                    return;
+                }
+                HoldLimit::Frames(remaining)
+            }
+        };
+    }
+
+    fn latch_active_commands(&mut self) {
+        for command in FighterCommands::iter() {
+            if self.has_command(command) {
+                self.latch_if_hold_enabled(command);
+            }
+        }
+    }
+
+    pub fn is_pressed(&self, action: DigitalAction) -> bool {
+        self.current_frame
+            .bindings_for(action)
+            .pressed_since(self.prev_frame.bindings_for(action))
+            .0
+            != 0
+    }
+
+    pub fn is_released(&self, action: DigitalAction) -> bool {
+        self.current_frame
+            .bindings_for(action)
+            .released_since(self.prev_frame.bindings_for(action))
+            .0
+            != 0
+    }
+
+    pub fn pressed_bindings(&self, action: DigitalAction) -> u16 {
+        self.current_frame
+            .bindings_for(action)
+            .pressed_since(self.prev_frame.bindings_for(action))
+            .0
+    }
+
+    pub fn binding_count(&self, action: DigitalAction) -> u32 {
+        self.current_frame.bindings_for(action).count()
     }
 
     pub fn get_frames_in_smash_move_deadzone(&self) -> u8 {
         self.frames_in_x_flick_deadzone
     }
-
     pub fn set_attack_command_type(&mut self, command: FighterAttackCommandType) {
         self.attack_command = command;
     }
-
     pub fn get_attack_command_type(&self) -> FighterAttackCommandType {
         self.attack_command
     }
+
+    fn hold_limit(&self, command: FighterCommands) -> HoldLimit {
+        let specific = self.hold_limits[command.index()];
+        match specific {
+            HoldOverride::Inherit => self.hold_all,
+            HoldOverride::Disabled => HoldLimit::Disabled,
+            HoldOverride::Frames(frames) => HoldLimit::Frames(frames),
+            HoldOverride::Infinite => HoldLimit::Infinite,
+        }
+    }
+
+    fn update_hold(&mut self, command: FighterCommands) {
+        let index = command.index();
+        let slot = &mut self.command_slots[index];
+        slot.age = slot.age.saturating_add(1);
+        match slot.hold_remaining {
+            HoldLimit::Disabled => {}
+            HoldLimit::Infinite => {
+                if slot.lifetime == 0 {
+                    slot.lifetime = 1;
+                }
+            }
+            HoldLimit::Frames(remaining) => {
+                // This tick consumes one of the total persistent frames, but
+                // the command remains active for the tick that consumes the
+                // final frame.
+                let remaining = remaining.saturating_sub(1);
+                slot.hold_remaining = if remaining == 0 {
+                    HoldLimit::Disabled
+                } else {
+                    HoldLimit::Frames(remaining)
+                };
+                if slot.lifetime == 0 {
+                    slot.lifetime = 1;
+                }
+            }
+        }
+    }
 }
 
-/// Turns this frame's rolled-back inputs into per-fighter [`FighterInput`]
-/// state. Runs in `GameplaySet::Input`, before any state looks at it.
 pub fn postprocess_input(
     query: Query<(&mut FighterInput, &Player)>,
     inputs: Res<PlayerInputs<GGRSCfg>>,
@@ -187,95 +433,95 @@ pub fn postprocess_input(
         }
 
         input.push_input_frame(inputs[player.handle].0);
+        let current_bindings = input.current_frame.bindings;
+        let previous_bindings = input.prev_frame.bindings;
+        for (history, action) in input.button_history.iter_mut().zip([
+            DigitalAction::Jump,
+            DigitalAction::Shield,
+            DigitalAction::Attack,
+        ]) {
+            history.update(
+                current_bindings.get(action).0,
+                previous_bindings.get(action).0,
+            );
+        }
 
-        // Directional smash detection
         let x_abs = input.current_frame.movement.x.abs();
         let y_abs = input.current_frame.movement.y.abs();
-
         let reset_deadzone = game_settings.input_common.smash_input_reset_axis_threshold;
         let axis_threshold = game_settings.input_common.smash_input_axis_threshold;
         let frame_threshold = game_settings.input_common.smash_input_frame_threshold;
 
         if x_abs < reset_deadzone {
             input.frames_in_x_flick_deadzone = 0xFE;
-        } else {
-            let prev_x_abs = input.prev_frame.movement.x.abs();
-            if prev_x_abs < reset_deadzone
+        } else if input.prev_frame.movement.x.abs() < reset_deadzone
             || input.prev_frame.movement.x.signum() != input.current_frame.movement.x.signum()
         {
             input.frames_in_x_flick_deadzone = 1;
         } else {
-                input.frames_in_x_flick_deadzone =
-                    input.frames_in_x_flick_deadzone.saturating_add(1);
-            }
+            input.frames_in_x_flick_deadzone = input.frames_in_x_flick_deadzone.saturating_add(1);
         }
 
         if y_abs < reset_deadzone {
             input.frames_in_y_flick_deadzone = 0xFE;
-        } else {
-            let prev_y_abs = input.prev_frame.movement.y.abs();
-            if prev_y_abs < reset_deadzone
+        } else if input.prev_frame.movement.y.abs() < reset_deadzone
             || input.prev_frame.movement.y.signum() != input.current_frame.movement.y.signum()
         {
             input.frames_in_y_flick_deadzone = 1;
         } else {
-                input.frames_in_y_flick_deadzone =
-                    input.frames_in_y_flick_deadzone.saturating_add(1);
-            }
+            input.frames_in_y_flick_deadzone = input.frames_in_y_flick_deadzone.saturating_add(1);
         }
 
-        if !input.prev_frame.jump && input.current_frame.jump {
-            input.set_lifetime(
-                FighterCommands::Jump,
-                game_settings.input_common.input_buffer_size,
-            );
+        let tap = game_settings.input_common.input_buffer_size;
+        let jump_pressed = input.is_pressed(DigitalAction::Jump);
+        let shield_pressed = input.is_pressed(DigitalAction::Shield);
+        let attack_pressed = input.is_pressed(DigitalAction::Attack);
+        if jump_pressed {
+            input.set_lifetime(FighterCommands::Jump, tap);
+        }
+        if shield_pressed {
+            input.set_lifetime(FighterCommands::Shield, tap);
         }
 
-        if !input.prev_frame.shield && input.current_frame.shield {
-            input.set_lifetime(
-                FighterCommands::Shield,
-                game_settings.input_common.input_buffer_size,
-            );
-        }
-
-        if !input.prev_frame.attack && input.current_frame.attack {
-            input.set_lifetime(
-                FighterCommands::Attack,
-                game_settings.input_common.input_buffer_size,
-            );
+        let shield_now = input.current_frame.bindings_for(DigitalAction::Shield);
+        let shield_previous = input.prev_frame.bindings_for(DigitalAction::Shield);
+        let second_shield_pressed = second_binding_pressed(shield_now, shield_previous);
+        if second_shield_pressed {
+            input.set_lifetime(FighterCommands::GuardHold, tap);
         }
 
         let mut y_flick_detected =
             y_abs >= axis_threshold && input.frames_in_y_flick_deadzone <= frame_threshold;
         let mut x_flick_detected =
             x_abs >= axis_threshold && input.frames_in_x_flick_deadzone <= frame_threshold;
-
         if y_flick_detected {
             input.clear_command(FighterCommands::SmashMoveUp);
             input.clear_command(FighterCommands::SmashMoveDown);
-
             input.frames_in_y_flick_deadzone = 0xFF;
-
-            let command_to_set = if input.current_frame.movement.y > 0.0 {
+            let command = if input.current_frame.movement.y > 0.0 {
                 FighterCommands::SmashMoveUp
             } else {
                 FighterCommands::SmashMoveDown
             };
-
-            input.set_lifetime(command_to_set, game_settings.input_common.input_buffer_size);
+            input.set_lifetime(command, tap);
+        }
+        if x_flick_detected {
+            input.clear_command(FighterCommands::SmashMoveLeft);
+            input.clear_command(FighterCommands::SmashMoveRight);
+            input.frames_in_x_flick_deadzone = 0xFF;
+            let command = if input.current_frame.movement.x > 0.0 {
+                FighterCommands::SmashMoveRight
+            } else {
+                FighterCommands::SmashMoveLeft
+            };
+            input.set_lifetime(command, tap);
         }
-
-        // if both flicks are detected, only one wins
-
         if x_flick_detected && y_flick_detected {
             x_flick_detected = x_abs > y_abs;
             y_flick_detected = !x_flick_detected;
         }
 
-        let attack_detected = input.current_frame.attack && !input.prev_frame.attack;
-
-        // Tilt/smash up/down
-        if attack_detected {
+        if attack_pressed {
             let attack_type = if y_flick_detected {
                 if input.current_frame.movement.y > 0.0 {
                     FighterAttackCommandType::SmashAttackUp
@@ -303,25 +549,144 @@ pub fn postprocess_input(
             } else {
                 FighterAttackCommandType::Neutral
             };
-
-            input.set_lifetime(
-                FighterCommands::Attack,
-                game_settings.input_common.input_buffer_size,
-            );
+            input.set_lifetime(FighterCommands::Attack, tap);
             input.set_attack_command_type(attack_type);
         }
 
-        if x_flick_detected {
-            input.clear_command(FighterCommands::SmashMoveLeft);
-            input.clear_command(FighterCommands::SmashMoveRight);
-
-            let command_to_set = if input.current_frame.movement.x > 0.0 {
-                FighterCommands::SmashMoveRight
-            } else {
-                FighterCommands::SmashMoveLeft
-            };
-
-            input.set_lifetime(command_to_set, game_settings.input_common.input_buffer_size);
+        // Advance each command's independently latched persistence. Physical
+        // source state is intentionally irrelevant after recognition.
+        for command in FighterCommands::iter() {
+            input.update_hold(command);
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::input::ActionBindingMask;
+
+    fn advance_command(input: &mut FighterInput, command: FighterCommands) {
+        input.reduce_command_lifetime(command);
+        input.update_hold(command);
+    }
+
+    #[test]
+    fn second_binding_is_an_edge_not_a_level() {
+        let first = ActionBindingMask(0b0001);
+        let both = ActionBindingMask(0b0011);
+        assert!(second_binding_pressed(both, first));
+        assert!(!second_binding_pressed(both, both));
+    }
+
+    #[test]
+    fn replacing_a_binding_still_triggers_the_combination() {
+        let previous = ActionBindingMask(0b0011);
+        let current = ActionBindingMask(0b0101);
+        assert!(second_binding_pressed(current, previous));
+    }
+
+    #[test]
+    fn command_can_be_consumed_without_erasing_raw_input() {
+        let mut input = FighterInput::default();
+        input.set_lifetime(FighterCommands::GuardHold, 3);
+        assert!(input.consume_command(FighterCommands::GuardHold));
+        assert!(!input.has_command(FighterCommands::GuardHold));
+        assert_eq!(input.get_last_frame(), FighterInputFrame::default());
+    }
+
+    #[test]
+    fn hold_extension_does_not_resurrect_consumed_commands() {
+        let mut input = FighterInput::default();
+        input.enable_hold(FighterCommands::Shield, 10);
+        input.set_lifetime(FighterCommands::Shield, 1);
+        input.update_hold(FighterCommands::Shield);
+        input.reduce_command_lifetime(FighterCommands::Shield);
+        input.update_hold(FighterCommands::Shield);
+        assert!(input.has_command(FighterCommands::Shield));
+        input.consume_command(FighterCommands::Shield);
+        input.update_hold(FighterCommands::Shield);
+        assert!(!input.has_command(FighterCommands::Shield));
+    }
+
+    #[test]
+    fn hold_buffer_keeps_released_attack_through_jump_squat() {
+        let mut input = FighterInput::default();
+        input.set_lifetime(FighterCommands::Attack, 3);
+        // Recognition happened before jump squat enabled persistence.
+        input.update_hold(FighterCommands::Attack);
+        input.enable_hold_all(10);
+
+        // Five simulation ticks cover the test fighter's jump squat. The
+        // physical attack binding is released, but persistence belongs to the
+        // recognized command rather than the binding's held state.
+        for _ in 0..5 {
+            advance_command(&mut input, FighterCommands::Attack);
+        }
+
+        assert!(input.has_command(FighterCommands::Attack));
+        // Jump-squat exit stops enrollment. The latch crosses into Jump and
+        // remains visible on its first airborne interrupt frame.
+        input.disable_hold_all();
+        advance_command(&mut input, FighterCommands::Attack);
+        assert!(input.has_command(FighterCommands::Attack));
+        assert!(input.consume_command(FighterCommands::Attack));
+        assert!(!input.has_command(FighterCommands::Attack));
+    }
+
+    #[test]
+    fn finite_hold_limit_includes_elapsed_tap_frames() {
+        let mut input = FighterInput::default();
+        input.set_lifetime(FighterCommands::Attack, 3);
+        // The recognition frame has already elapsed when jump squat starts.
+        input.update_hold(FighterCommands::Attack);
+        input.enable_hold_all(10);
+
+        for _ in 0..9 {
+            advance_command(&mut input, FighterCommands::Attack);
+            assert!(input.has_command(FighterCommands::Attack));
+        }
+        advance_command(&mut input, FighterCommands::Attack);
+        assert!(!input.has_command(FighterCommands::Attack));
+    }
+
+    #[test]
+    fn stopping_enrollment_and_cancelling_latches_are_distinct() {
+        let mut input = FighterInput::default();
+        input.enable_hold_all(10);
+        input.set_lifetime(FighterCommands::Shield, 1);
+        input.disable_hold_all();
+        advance_command(&mut input, FighterCommands::Shield);
+        assert!(input.has_command(FighterCommands::Shield));
+
+        input.cancel_hold_all();
+        advance_command(&mut input, FighterCommands::Shield);
+        assert!(!input.has_command(FighterCommands::Shield));
+    }
+
+    #[test]
+    fn command_override_can_disable_global_hold() {
+        let mut input = FighterInput::default();
+        input.enable_hold_all(10);
+        input.disable_hold(FighterCommands::Attack);
+        input.set_lifetime(FighterCommands::Attack, 1);
+        advance_command(&mut input, FighterCommands::Attack);
+        assert!(!input.has_command(FighterCommands::Attack));
+
+        input.reset_hold_override(FighterCommands::Attack);
+        input.set_lifetime(FighterCommands::Attack, 1);
+        advance_command(&mut input, FighterCommands::Attack);
+        assert!(input.has_command(FighterCommands::Attack));
+    }
+
+    #[test]
+    fn infinite_hold_uses_an_explicit_state() {
+        let mut input = FighterInput::default();
+        input.enable_hold(FighterCommands::Shield, 0);
+        input.set_lifetime(FighterCommands::Shield, 1);
+        for _ in 0..u16::MAX as usize + 1 {
+            advance_command(&mut input, FighterCommands::Shield);
+        }
+        assert!(input.has_command(FighterCommands::Shield));
+    }
+}

src/input/frame.rs

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

src/input/gamepad.rs

@@ -14,10 +14,13 @@ pub fn sample_gamepad(pad: &Gamepad, input_map: &BaseInputMap) -> FighterInputFr
         match &gamepad_element.binding {
             GamepadBinding::Button(button) => {
                 let pressed = pad.pressed(*button);
+                if let Some(action) = gamepad_element.action.digital_action() {
+                    input_frame
+                        .bindings
+                        .set(action, gamepad_element.binding_slot, pressed);
+                }
                 match gamepad_element.action {
-                    InputMapAction::Jump => input_frame.jump |= pressed,
-                    InputMapAction::Shield => input_frame.shield |= pressed,
-                    InputMapAction::Attack => input_frame.attack |= pressed,
+                    InputMapAction::Jump | InputMapAction::Shield | InputMapAction::Attack => {}
                     // Digital buttons driving movement isn't used by the
                     // default bindings (the stick covers that), but stay
                     // consistent with the keyboard backend if one is added.

src/input/keyboard.rs

@@ -30,9 +30,15 @@ pub fn sample_keyboard(key: &ButtonInput<KeyCode>, input_map: &BaseInputMap) ->
             InputMapAction::MovementYDir(sign) => {
                 input_frame.movement.y += (sign) * action_strength
             }
-            InputMapAction::Jump => input_frame.jump = action_strength != FGi32::ZERO,
-            InputMapAction::Shield => input_frame.shield = action_strength != FGi32::ZERO,
-            InputMapAction::Attack => input_frame.attack = action_strength != FGi32::ZERO,
+            InputMapAction::Jump | InputMapAction::Shield | InputMapAction::Attack => {
+                if let Some(action) = keyboard_elment.action.digital_action() {
+                    input_frame.bindings.set(
+                        action,
+                        keyboard_elment.binding_slot,
+                        action_strength != FGi32::ZERO,
+                    );
+                }
+            }
         }
     }
 

src/input/map.rs

@@ -19,6 +19,17 @@ pub enum InputMapAction {
     Attack,
 }
 
+impl InputMapAction {
+    pub const fn digital_action(&self) -> Option<crate::input::DigitalAction> {
+        match self {
+            Self::Jump => Some(crate::input::DigitalAction::Jump),
+            Self::Shield => Some(crate::input::DigitalAction::Shield),
+            Self::Attack => Some(crate::input::DigitalAction::Attack),
+            Self::MovementXDir(_) | Self::MovementYDir(_) => None,
+        }
+    }
+}
+
 #[derive(Debug)]
 pub enum MenuInputMapAction {
     MovementXDir(i32),
@@ -32,6 +43,7 @@ pub enum MenuInputMapAction {
 pub struct KeyboardInputMapElement {
     pub key: KeyCode,
     pub action: InputMapAction,
+    pub binding_slot: u8,
 }
 
 #[derive(Debug)]
@@ -44,6 +56,7 @@ pub enum GamepadBinding {
 pub struct GamepadInputMapElement {
     pub binding: GamepadBinding,
     pub action: InputMapAction,
+    pub binding_slot: u8,
 }
 
 #[derive(Debug)]

src/input/mod.rs

@@ -15,7 +15,7 @@ pub mod keyboard;
 pub mod map;
 
 pub use buffer::{FighterCommands, FighterInput};
-pub use frame::FighterInputFrame;
+pub use frame::{ActionBindingMask, DigitalAction, DigitalActionBindings, FighterInputFrame};
 pub use map::{
     BaseInputMap, GamepadBinding, GamepadInputMapElement, InputActionState, InputMapAction,
     KeyboardInputMapElement, MenuGamepadInputMapElement, MenuInputMap, MenuInputMapAction,
@@ -78,36 +78,43 @@ impl Plugin for FighterInputPlugin {
                 KeyboardInputMapElement {
                     key: KeyCode::KeyD,
                     action: InputMapAction::MovementXDir(1),
+                    binding_slot: 0,
                 },
                 // left
                 KeyboardInputMapElement {
                     key: KeyCode::KeyA,
                     action: InputMapAction::MovementXDir(-1),
+                    binding_slot: 0,
                 },
                 // up
                 KeyboardInputMapElement {
                     key: KeyCode::KeyW,
                     action: InputMapAction::MovementYDir(1),
+                    binding_slot: 0,
                 },
                 // down
                 KeyboardInputMapElement {
                     key: KeyCode::KeyS,
                     action: InputMapAction::MovementYDir(-1),
+                    binding_slot: 0,
                 },
                 // jump
                 KeyboardInputMapElement {
                     key: KeyCode::Space,
                     action: InputMapAction::Jump,
+                    binding_slot: 0,
                 },
                 // shield/airdodge
                 KeyboardInputMapElement {
                     key: KeyCode::ShiftLeft,
                     action: InputMapAction::Shield,
+                    binding_slot: 0,
                 },
                 // attack
                 KeyboardInputMapElement {
                     key: KeyCode::KeyJ,
                     action: InputMapAction::Attack,
+                    binding_slot: 0,
                 },
                 // Menu
             ],
@@ -116,28 +123,34 @@ impl Plugin for FighterInputPlugin {
                 GamepadInputMapElement {
                     binding: GamepadBinding::Axis(GamepadAxis::LeftStickX, 1),
                     action: InputMapAction::MovementXDir(1),
+                    binding_slot: 0,
                 },
                 GamepadInputMapElement {
                     binding: GamepadBinding::Axis(GamepadAxis::LeftStickY, 1),
                     action: InputMapAction::MovementYDir(1),
+                    binding_slot: 0,
                 },
                 // jump
                 GamepadInputMapElement {
                     binding: GamepadBinding::Button(GamepadButton::North),
                     action: InputMapAction::Jump,
+                    binding_slot: 0,
                 },
                 GamepadInputMapElement {
                     binding: GamepadBinding::Button(GamepadButton::LeftTrigger2),
                     action: InputMapAction::Shield,
+                    binding_slot: 0,
                 },
                 GamepadInputMapElement {
                     binding: GamepadBinding::Button(GamepadButton::RightTrigger2),
                     action: InputMapAction::Shield,
+                    binding_slot: 1,
                 },
                 // attack
                 GamepadInputMapElement {
                     binding: GamepadBinding::Button(GamepadButton::East),
                     action: InputMapAction::Attack,
+                    binding_slot: 0,
                 },
             ],
         })