src/match_runtime.rs

@@ -1,9 +1,14 @@
 //! Rollback-simulated state for an active match.
 
+use bevy::input::InputSystems;
 use bevy::prelude::*;
-use bevy_ggrs::prelude::*;
+use bevy_ggrs::{RunGgrsSystems, prelude::*};
 
-use crate::match_loading::{MatchConfig, MatchRules};
+use crate::{
+    AppState,
+    match_loading::{MatchConfig, MatchRules},
+    netcode::session::SessionConfig,
+};
 
 #[derive(Resource, Clone, Debug, Hash, PartialEq, Eq)]
 pub struct MatchState {
@@ -19,6 +24,11 @@ pub struct PlayerMatchState {
     pub deaths: u32,
 }
 
+#[derive(Resource, Debug, Default, Clone, Copy, PartialEq, Eq)]
+pub struct PauseState {
+    pub paused: bool,
+}
+
 impl MatchState {
     pub fn from_config(config: &MatchConfig) -> Self {
         let stocks_remaining = match &config.rules {
@@ -46,10 +56,56 @@ pub struct MatchRuntimePlugin;
 impl Plugin for MatchRuntimePlugin {
     fn build(&self, app: &mut App) {
         app.rollback_resource_with_clone::<MatchState>()
-            .checksum_resource_with_hash::<MatchState>();
+            .checksum_resource_with_hash::<MatchState>()
+            .init_resource::<PauseState>()
+            .configure_sets(PreUpdate, RunGgrsSystems.run_if(ggrs_should_run))
+            .add_systems(OnEnter(AppState::InMatch), reset_pause)
+            .add_systems(OnExit(AppState::InMatch), reset_pause)
+            .add_systems(
+                PreUpdate,
+                toggle_pause
+                    .after(InputSystems)
+                    .before(RunGgrsSystems)
+                    .run_if(in_state(AppState::InMatch)),
+            );
     }
 }
 
+pub fn ggrs_should_run(pause: Option<Res<PauseState>>) -> bool {
+    !pause.is_some_and(|pause| pause.paused)
+}
+
+fn toggle_pause(
+    key: Res<ButtonInput<KeyCode>>,
+    gamepads: Query<&Gamepad>,
+    session: Res<SessionConfig>,
+    mut pause: ResMut<PauseState>,
+    mut virtual_time: ResMut<Time<Virtual>>,
+) {
+    if session.is_multiplayer() {
+        return;
+    }
+
+    let pressed = key.just_pressed(KeyCode::Escape)
+        || gamepads
+            .iter()
+            .any(|gamepad| gamepad.just_pressed(GamepadButton::Start));
+    if !pressed {
+        return;
+    }
+
+    pause.paused = !pause.paused;
+    virtual_time.toggle();
+}
+
+fn reset_pause(
+    mut pause: ResMut<PauseState>,
+    mut virtual_time: ResMut<Time<Virtual>>,
+) {
+    pause.paused = false;
+    virtual_time.unpause();
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/menus/input.rs

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

src/netcode/session.rs

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

src/ui/mod.rs

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