Add dungeon example

This gives us an example that _actually_ showcases
what this library is capable of providing.

Cargo.toml

@@ -8,13 +8,15 @@ authors = ["James Gayfer"]
 repository = "https://github.com/jgayfer/bevy_light_2d"
 license-file = "LICENSE"
 readme = "README.md"
+exclude = ["assets/*", "static/*"]
 
 [dependencies]
 bevy = { version = "0.13", default-features = false, features = [
     "bevy_render",
     "bevy_core_pipeline",
     "bevy_winit",
     "bevy_sprite",
+    "png",
     "x11"
 ] }
 
@@ -34,3 +36,7 @@ path = "examples/basic.rs"
 [[example]]
 name = "multiple"
 path = "examples/multiple.rs"
+
+[[example]]
+name = "dungeon"
+path = "examples/dungeon.rs"

README.md

@@ -8,6 +8,8 @@
 A general purpose 2d lighting plugin for [`bevy`](https://bevyengine.org/).
 Designed to be simple to use, yet expressive enough to fit a variety of needs.
 
+<img src="https://github.com/jgayfer/bevy_light_2d/blob/main/static/dungeon.gif" width="400">
+
 ## Features
 
 - Component driven design
@@ -79,3 +81,7 @@ I'd like to thank the authors of the below crates; they were a significant sourc
 - [`bevy-magic-light-2d`](https://github.com/zaycev/bevy-magic-light-2d)
 - [`bevy_2d_screen_space_lightmaps`](https://github.com/goto64/bevy_2d_screen_space_lightmaps)
 - [`bevy_incandescent`](https://github.com/443eb9/bevy_incandescent)
+
+## Asset credits
+
+- [Pixel Dungeon](https://pixel-poem.itch.io/dungeon-assetpuck) by [`pixel_poem`](https://pixel-poem.itch.io/)

examples/candle.rs

@@ -0,0 +1,250 @@
+use bevy::prelude::*;
+use bevy_light_2d::prelude::*;
+
+const TILE_INDEX: f32 = 0.0;
+const ENTITY_INDEX: f32 = 1.0;
+
+fn main() {
+    App::new()
+        .add_plugins((
+            DefaultPlugins.set(ImagePlugin::default_nearest()),
+            Light2dPlugin,
+        ))
+        .init_resource::<DungeonTileset>()
+        .init_resource::<CandleSpritesheet>()
+        .add_systems(Startup, (setup_camera, set_clear_color))
+        .add_systems(Startup, (setup_dungeon_tileset, spawn_tiles).chain())
+        .add_systems(Startup, (setup_candle_spritesheet, spawn_candles).chain())
+        .add_systems(Update, animate_candles)
+        .run()
+}
+
+#[derive(Resource, Default)]
+struct DungeonTileset {
+    layout: Handle<TextureAtlasLayout>,
+    texture: Handle<Image>,
+}
+
+#[derive(Resource, Default)]
+struct CandleSpritesheet {
+    layout: Handle<TextureAtlasLayout>,
+    texture: Handle<Image>,
+}
+
+#[derive(Component)]
+struct Candle;
+
+#[derive(Component, Deref, DerefMut)]
+struct AnimationTimer(Timer);
+
+fn setup_camera(mut commands: Commands) {
+    let mut camera = Camera2dBundle::default();
+    camera.projection.scale = 0.25;
+    commands.spawn((
+        camera,
+        AmbientLight2d {
+            brightness: 0.1,
+            ..default()
+        },
+    ));
+}
+
+fn set_clear_color(mut clear_color: ResMut<ClearColor>) {
+    clear_color.0 = Color::rgb_u8(37, 19, 26);
+}
+
+fn animate_candles(
+    time: Res<Time>,
+    mut query: Query<(&mut AnimationTimer, &mut TextureAtlas), With<Candle>>,
+) {
+    for (mut timer, mut atlas) in &mut query {
+        timer.tick(time.delta());
+        if timer.just_finished() {
+            atlas.index = (atlas.index + 1) % 4;
+        }
+    }
+}
+
+fn spawn_candles(mut commands: Commands, spritesheet: Res<CandleSpritesheet>) {
+    let light = commands
+        .spawn((PointLight2dBundle {
+            transform: Transform::from_xyz(0.0, 4.0, ENTITY_INDEX),
+            point_light: PointLight2d {
+                radius: 48.0,
+                color: Color::YELLOW,
+                intensity: 25.0,
+                falloff: 4.0,
+            },
+            ..default()
+        },))
+        .id();
+
+    commands
+        .spawn((
+            Candle,
+            AnimationTimer(Timer::from_seconds(0.2, TimerMode::Repeating)),
+            SpriteSheetBundle {
+                transform: Transform::from_xyz(0., 2., ENTITY_INDEX),
+                texture: spritesheet.texture.clone(),
+                atlas: TextureAtlas {
+                    layout: spritesheet.layout.clone(),
+                    ..default()
+                },
+                ..default()
+            },
+        ))
+        .add_child(light);
+}
+
+fn spawn_tiles(mut commands: Commands, tileset: Res<DungeonTileset>) {
+    let mut spawn_wall_tile = |position: (i32, i32), index: usize| {
+        spawn_from_atlas(
+            &mut commands,
+            tile_translation(position.0, position.1).extend(TILE_INDEX),
+            index,
+            tileset.layout.clone(),
+            tileset.texture.clone(),
+        );
+    };
+
+    // First row
+    spawn_wall_tile((-3, 2), LEFT_WALL_A);
+    spawn_wall_tile((-2, 2), TOP_WALL_A);
+    spawn_wall_tile((-1, 2), TOP_WALL_B);
+    spawn_wall_tile((0, 2), TOP_WALL_C);
+    spawn_wall_tile((1, 2), TOP_WALL_A);
+    spawn_wall_tile((2, 2), TOP_WALL_D);
+    spawn_wall_tile((3, 2), RIGHT_WALL_A);
+
+    // Second row
+    spawn_wall_tile((-3, 1), LEFT_WALL_B);
+    spawn_wall_tile((-2, 1), TOP_LEFT_FLOOR);
+    spawn_wall_tile((-1, 1), TOP_FLOOR_A);
+    spawn_wall_tile((0, 1), TOP_FLOOR_B);
+    spawn_wall_tile((1, 1), TOP_FLOOR_A);
+    spawn_wall_tile((2, 1), TOP_RIGHT_FLOOR);
+    spawn_wall_tile((3, 1), RIGHT_WALL_B);
+
+    // Third row
+    spawn_wall_tile((-3, 0), LEFT_WALL_C);
+    spawn_wall_tile((-2, 0), LEFT_FLOOR);
+    spawn_wall_tile((-1, 0), FLOOR_A);
+    spawn_wall_tile((0, 0), FLOOR_B);
+    spawn_wall_tile((1, 0), FLOOR_A);
+    spawn_wall_tile((2, 0), RIGHT_FLOOR);
+    spawn_wall_tile((3, 0), RIGHT_WALL_C);
+
+    // Fourth row
+    spawn_wall_tile((-3, -1), LEFT_WALL_D);
+    spawn_wall_tile((-2, -1), BOTTOM_LEFT_FLOOR);
+    spawn_wall_tile((-1, -1), BOTTOM_FLOOR_A);
+    spawn_wall_tile((0, -1), BOTTOM_FLOOR_B);
+    spawn_wall_tile((1, -1), BOTTOM_FLOOR_B);
+    spawn_wall_tile((2, -1), BOTTOM_RIGHT_FLOOR);
+    spawn_wall_tile((3, -1), RIGHT_WALL_D);
+
+    // Bottom row
+    spawn_wall_tile((-3, -2), BOTTOM_LEFT_WALL);
+    spawn_wall_tile((-2, -2), BOTTOM_WALL_A);
+    spawn_wall_tile((-1, -2), BOTTOM_WALL_B);
+    spawn_wall_tile((0, -2), BOTTOM_WALL_C);
+    spawn_wall_tile((1, -2), BOTTOM_WALL_A);
+    spawn_wall_tile((2, -2), BOTTOM_WALL_D);
+    spawn_wall_tile((3, -2), BOTTOM_RIGHT_WALL);
+}
+
+fn tile_translation(x: i32, y: i32) -> Vec2 {
+    Vec2::new(x as f32 * 16.0, y as f32 * 16.0)
+}
+
+fn spawn_from_atlas(
+    commands: &mut Commands,
+    translation: Vec3,
+    sprite_index: usize,
+    atlas_handle: Handle<TextureAtlasLayout>,
+    texture: Handle<Image>,
+) {
+    commands.spawn(SpriteSheetBundle {
+        transform: Transform {
+            translation,
+            ..default()
+        },
+        texture,
+        atlas: TextureAtlas {
+            index: sprite_index,
+            layout: atlas_handle,
+        },
+        ..default()
+    });
+}
+
+fn setup_dungeon_tileset(
+    asset_server: Res<AssetServer>,
+    mut texture_atlas_layouts: ResMut<Assets<TextureAtlasLayout>>,
+    mut dungeon_tileset: ResMut<DungeonTileset>,
+) {
+    dungeon_tileset.texture = asset_server.load("dungeon_tiles.png");
+    dungeon_tileset.layout = texture_atlas_layouts.add(TextureAtlasLayout::from_grid(
+        Vec2::new(16.0, 16.0),
+        10,
+        10,
+        None,
+        None,
+    ));
+}
+
+fn setup_candle_spritesheet(
+    asset_server: Res<AssetServer>,
+    mut texture_atlas_layouts: ResMut<Assets<TextureAtlasLayout>>,
+    mut candle_spritesheet: ResMut<CandleSpritesheet>,
+) {
+    candle_spritesheet.texture = asset_server.load("candle.png");
+    candle_spritesheet.layout = texture_atlas_layouts.add(TextureAtlasLayout::from_grid(
+        Vec2::new(16.0, 16.0),
+        4,
+        1,
+        None,
+        None,
+    ));
+}
+
+const TOP_WALL_A: usize = 1;
+const TOP_WALL_B: usize = 2;
+const TOP_WALL_C: usize = 3;
+const TOP_WALL_D: usize = 4;
+
+const LEFT_WALL_A: usize = 0;
+const LEFT_WALL_B: usize = 10;
+const LEFT_WALL_C: usize = 20;
+const LEFT_WALL_D: usize = 20;
+
+const RIGHT_WALL_A: usize = 5;
+const RIGHT_WALL_B: usize = 15;
+const RIGHT_WALL_C: usize = 25;
+const RIGHT_WALL_D: usize = 35;
+
+const BOTTOM_LEFT_WALL: usize = 40;
+const BOTTOM_RIGHT_WALL: usize = 45;
+
+const BOTTOM_WALL_A: usize = 41;
+const BOTTOM_WALL_B: usize = 42;
+const BOTTOM_WALL_C: usize = 43;
+const BOTTOM_WALL_D: usize = 44;
+
+const TOP_LEFT_FLOOR: usize = 11;
+const TOP_RIGHT_FLOOR: usize = 14;
+
+const TOP_FLOOR_A: usize = 12;
+const TOP_FLOOR_B: usize = 13;
+
+const LEFT_FLOOR: usize = 21;
+const RIGHT_FLOOR: usize = 24;
+
+const BOTTOM_LEFT_FLOOR: usize = 31;
+const BOTTOM_RIGHT_FLOOR: usize = 34;
+
+const BOTTOM_FLOOR_A: usize = 32;
+const BOTTOM_FLOOR_B: usize = 33;
+
+const FLOOR_A: usize = 22;
+const FLOOR_B: usize = 23;