Invert colors kinda sorta works

assets/flappy/CREDITS

@@ -6,4 +6,4 @@ Art Assets: Kenney.nl
 Engine: Bevy
 Physics: Avian2D
 
-Inspired by the 2013 Flappy Bird by Dong Nguyen
+Inspired by Flappy Bird (2013) by Dong Nguyen

src/bin/flappy/main.rs

@@ -16,6 +16,7 @@ fn main() {
             Physics2dPlugin,
         ))
         .insert_resource(Gravity(Vec2::NEG_Y * 9.8 * 100.0))
+        .init_resource::<BirdAssets>()
         .init_resource::<PipeAssets>()
         .init_resource::<GroundAssets>()
         .init_resource::<Score>()
@@ -26,16 +27,17 @@ fn main() {
         .add_systems(
             Startup,
             (
-                init_bird,
                 // init_obstacles,
-                init_obstacle_assets,
+                init_assets,
-                init_first_batches.after(init_obstacle_assets),
+                init_bird.after(init_assets),
+                init_first_batches.after(init_assets),
                 init_ui,
                 tweak_camera.after(create_camera_2d),
             ),
         )
         .add_systems(OnEnter(PlayerState::Alive), alive_bird)
-        .add_systems(OnEnter(PlayerState::Rewind), alive_bird)
+        .add_systems(OnEnter(PlayerState::Rewind), (invert_colors, alive_bird))
+        .add_systems(OnExit(PlayerState::Rewind), uninvert_colors)
         .add_systems(OnEnter(PlayerState::Pause), pause_bird)
         .add_systems(OnEnter(PlayerState::Stasis), pause_bird)
         .add_systems(
@@ -133,18 +135,10 @@ struct Tape {
 fn init_bird(
     mut commands: Commands,
     server: Res<AssetServer>,
+    bird_assets: Res<BirdAssets>,
     mut meshes: ResMut<Assets<Mesh>>,
     mut materials: ResMut<Assets<ColorMaterial>>,
 ) {
-    let material = MeshMaterial2d(materials.add(ColorMaterial {
-        texture: Some(server.load("flappy/bird.png")),
-        color: ORANGE.into(),
-        alpha_mode: AlphaMode2d::Blend,
-        ..default()
-    }));
-
-    let mesh = Mesh2d(meshes.add(Rectangle::new(1.0, 1.2)));
-
     let name = Name::new("bird");
 
     let t = Transform::from_xyz(0.0, 0.0, 0.0).with_scale(Vec3::splat(50.0));
@@ -161,8 +155,8 @@ fn init_bird(
 
     commands.spawn((
         name,
-        mesh,
+        bird_assets.mesh.clone(),
-        material,
+        bird_assets.material.clone(),
         physics,
         t,
         Bird,
@@ -318,22 +312,32 @@ fn populate_hitbox(trigger: Trigger<OnAdd, Hitbox>, mut commands: Commands) {
     ));
 }
 
+#[derive(Resource, Default)]
+struct BirdAssets {
+    material: MeshMaterial2d<ColorMaterial>,
+    rewind_material: MeshMaterial2d<ColorMaterial>,
+    mesh: Mesh2d,
+}
+
 #[derive(Resource, Default)]
 struct GroundAssets {
     material: MeshMaterial2d<ColorMaterial>,
+    rewind_material: MeshMaterial2d<ColorMaterial>,
     mesh: Mesh2d,
 }
 
 #[derive(Resource, Default)]
 struct PipeAssets {
     material: MeshMaterial2d<ColorMaterial>,
+    rewind_material: MeshMaterial2d<ColorMaterial>,
     mesh: Mesh2d,
 }
 
 /// Initialize some materials and meshes used by the environment obstacles
-fn init_obstacle_assets(
+fn init_assets(
     mut meshes: ResMut<Assets<Mesh>>,
     mut materials: ResMut<Assets<ColorMaterial>>,
+    mut bird_assets: ResMut<BirdAssets>,
     mut pipe_assets: ResMut<PipeAssets>,
     mut ground_assets: ResMut<GroundAssets>,
     server: Res<AssetServer>,
@@ -343,6 +347,11 @@ fn init_obstacle_assets(
         color: GREEN.into(),
         ..default()
     }));
+    pipe_assets.rewind_material = MeshMaterial2d(materials.add(ColorMaterial {
+        texture: Some(server.load("flappy/pipe.png")),
+        color: (WHITE - GREEN).with_alpha(1.0).into(),
+        ..default()
+    }));
     pipe_assets.mesh = Mesh2d(meshes.add(Rectangle::new(1.0, 1.0)));
 
     ground_assets.material = MeshMaterial2d(materials.add(ColorMaterial {
@@ -350,8 +359,26 @@ fn init_obstacle_assets(
         color: BLACK.into(),
         ..default()
     }));
-
+    ground_assets.rewind_material = MeshMaterial2d(materials.add(ColorMaterial {
+        texture: Some(server.load("flappy/ground.png")),
+        color: WHITE.into(),
+        ..default()
+    }));
     ground_assets.mesh = Mesh2d(meshes.add(Rectangle::new(1.0, 1.0)));
+
+    bird_assets.material = MeshMaterial2d(materials.add(ColorMaterial {
+        texture: Some(server.load("flappy/bird.png")),
+        color: ORANGE.into(),
+        alpha_mode: AlphaMode2d::Blend,
+        ..default()
+    }));
+    bird_assets.rewind_material = MeshMaterial2d(materials.add(ColorMaterial {
+        texture: Some(server.load("flappy/bird.png")),
+        color: (WHITE - ORANGE).with_alpha(1.0).into(),
+        alpha_mode: AlphaMode2d::Blend,
+        ..default()
+    }));
+    bird_assets.mesh = Mesh2d(meshes.add(Rectangle::new(1.0, 1.2)));
 }
 
 fn init_ui(mut commands: Commands) {
@@ -884,3 +911,59 @@ fn update_tooltip(
         })
     });
 }
+
+fn invert_colors(
+    camera: Single<&mut Camera>,
+    mut materials: Query<&mut MeshMaterial2d<ColorMaterial>>,
+    birds: Query<Entity, With<Bird>>,
+    bird_assets: ResMut<BirdAssets>,
+    pipes: Query<Entity, With<Pipe>>,
+    pipe_assets: ResMut<PipeAssets>,
+    grounds: Query<Entity, With<Ground>>,
+    ground_assets: ResMut<GroundAssets>,
+) {
+    // Invert bird
+    birds.iter().for_each(|e| {
+        *materials.get_mut(e).unwrap() = bird_assets.rewind_material.clone();
+    });
+    // Set pipes
+    pipes.iter().for_each(|e| {
+        *materials.get_mut(e).unwrap() = pipe_assets.rewind_material.clone();
+    });
+    // Set ground
+    grounds.iter().for_each(|e| {
+        *materials.get_mut(e).unwrap() = ground_assets.rewind_material.clone();
+    });
+
+    // Set background color
+    let mut c = camera.into_inner();
+    c.clear_color = ClearColorConfig::Custom(BLACK.into());
+}
+
+fn uninvert_colors(
+    camera: Single<&mut Camera>,
+    mut materials: Query<&mut MeshMaterial2d<ColorMaterial>>,
+    birds: Query<Entity, With<Bird>>,
+    bird_assets: ResMut<BirdAssets>,
+    pipes: Query<Entity, With<Pipe>>,
+    pipe_assets: ResMut<PipeAssets>,
+    grounds: Query<Entity, With<Ground>>,
+    ground_assets: ResMut<GroundAssets>,
+) {
+    // Set bird
+    birds.iter().for_each(|e| {
+        *materials.get_mut(e).unwrap() = bird_assets.material.clone();
+    });
+    // Set pipes
+    pipes.iter().for_each(|e| {
+        *materials.get_mut(e).unwrap() = pipe_assets.material.clone();
+    });
+    // Set ground
+    grounds.iter().for_each(|e| {
+        *materials.get_mut(e).unwrap() = ground_assets.material.clone();
+    });
+
+    // Set background color
+    let mut c = camera.into_inner();
+    c.clear_color = ClearColorConfig::Custom(WHITE.into());
+}