//! Demonstrates picking for sprites and sprite atlases. The picking backend only tests against the //! sprite bounds, so the sprite atlas can be picked by clicking on its transparent areas. use bevy::{prelude::*, sprite::Anchor}; use std::fmt::Debug; fn main() { App::new() .add_plugins(DefaultPlugins.set(ImagePlugin::default_nearest())) .add_systems(Startup, (setup, setup_atlas)) .add_systems(Update, (move_sprite, animate_sprite)) .run(); } fn move_sprite( time: Res<Time>, mut sprite: Query<&mut Transform, (Without<Sprite>, With<Children>)>, ) { let t = time.elapsed_secs() * 0.1; for mut transform in &mut sprite { let new = Vec2 { x: 50.0 * ops::sin(t), y: 50.0 * ops::sin(t * 2.0), }; transform.translation.x = new.x; transform.translation.y = new.y; } } /// Set up a scene that tests all sprite anchor types. fn setup(mut commands: Commands, asset_server: Res<AssetServer>) { commands.spawn(Camera2d); let len = 128.0; let sprite_size = Vec2::splat(len / 2.0); commands .spawn((Transform::default(), Visibility::default())) .with_children(|commands| { for (anchor_index, anchor) in [ Anchor::TopLeft, Anchor::TopCenter, Anchor::TopRight, Anchor::CenterLeft, Anchor::Center, Anchor::CenterRight, Anchor::BottomLeft, Anchor::BottomCenter, Anchor::BottomRight, Anchor::Custom(Vec2::new(0.5, 0.5)), ] .iter() .enumerate() { let i = (anchor_index % 3) as f32; let j = (anchor_index / 3) as f32; // spawn black square behind sprite to show anchor point commands .spawn(( Sprite::from_color(Color::BLACK, sprite_size), Transform::from_xyz(i * len - len, j * len - len, -1.0), )) .observe(recolor_on::<Pointer<Over>>(Color::srgb(0.0, 1.0, 1.0))) .observe(recolor_on::<Pointer<Out>>(Color::BLACK)) .observe(recolor_on::<Pointer<Pressed>>(Color::srgb(1.0, 1.0, 0.0))) .observe(recolor_on::<Pointer<Released>>(Color::srgb(0.0, 1.0, 1.0))); commands .spawn(( Sprite { image: asset_server.load("branding/bevy_bird_dark.png"), custom_size: Some(sprite_size), color: Color::srgb(1.0, 0.0, 0.0), anchor: anchor.to_owned(), ..default() }, // 3x3 grid of anchor examples by changing transform Transform::from_xyz(i * len - len, j * len - len, 0.0) .with_scale(Vec3::splat(1.0 + (i - 1.0) * 0.2)) .with_rotation(Quat::from_rotation_z((j - 1.0) * 0.2)), )) .observe(recolor_on::<Pointer<Over>>(Color::srgb(0.0, 1.0, 0.0))) .observe(recolor_on::<Pointer<Out>>(Color::srgb(1.0, 0.0, 0.0))) .observe(recolor_on::<Pointer<Pressed>>(Color::srgb(0.0, 0.0, 1.0))) .observe(recolor_on::<Pointer<Released>>(Color::srgb(0.0, 1.0, 0.0))); } }); } #[derive(Component)] struct AnimationIndices { first: usize, last: usize, } #[derive(Component, Deref, DerefMut)] struct AnimationTimer(Timer); fn animate_sprite( time: Res<Time>, mut query: Query<(&AnimationIndices, &mut AnimationTimer, &mut Sprite)>, ) { for (indices, mut timer, mut sprite) in &mut query { let Some(texture_atlas) = &mut sprite.texture_atlas else { continue; }; timer.tick(time.delta()); if timer.just_finished() { texture_atlas.index = if texture_atlas.index == indices.last { indices.first } else { texture_atlas.index + 1 }; } } } fn setup_atlas( mut commands: Commands, asset_server: Res<AssetServer>, mut texture_atlas_layouts: ResMut<Assets<TextureAtlasLayout>>, ) { let texture_handle = asset_server.load("textures/rpg/chars/gabe/gabe-idle-run.png"); let layout = TextureAtlasLayout::from_grid(UVec2::new(24, 24), 7, 1, None, None); let texture_atlas_layout_handle = texture_atlas_layouts.add(layout); // Use only the subset of sprites in the sheet that make up the run animation let animation_indices = AnimationIndices { first: 1, last: 6 }; commands .spawn(( Sprite::from_atlas_image( texture_handle, TextureAtlas { layout: texture_atlas_layout_handle, index: animation_indices.first, }, ), Transform::from_xyz(300.0, 0.0, 0.0).with_scale(Vec3::splat(6.0)), animation_indices, AnimationTimer(Timer::from_seconds(0.1, TimerMode::Repeating)), )) .observe(recolor_on::<Pointer<Over>>(Color::srgb(0.0, 1.0, 1.0))) .observe(recolor_on::<Pointer<Out>>(Color::srgb(1.0, 1.0, 1.0))) .observe(recolor_on::<Pointer<Pressed>>(Color::srgb(1.0, 1.0, 0.0))) .observe(recolor_on::<Pointer<Released>>(Color::srgb(0.0, 1.0, 1.0))); } // An observer listener that changes the target entity's color. fn recolor_on<E: Debug + Clone + Reflect>(color: Color) -> impl Fn(Trigger<E>, Query<&mut Sprite>) { move |ev, mut sprites| { let Ok(mut sprite) = sprites.get_mut(ev.target()) else { return; }; sprite.color = color; } }