# Objective Fixes #14883 ## Solution Pretty simple update to `EntityCommands` methods to consume `self` and return it rather than taking `&mut self`. The things probably worth noting: * I added `#[allow(clippy::should_implement_trait)]` to the `add` method because it causes a linting conflict with `std::ops::Add`. * `despawn` and `log_components` now return `Self`. I'm not sure if that's exactly the desired behavior so I'm happy to adjust if that seems wrong. ## Testing Tested with `cargo run -p ci`. I think that should be sufficient to call things good. ## Migration Guide The most likely migration needed is changing code from this: ``` let mut entity = commands.get_or_spawn(entity); if depth_prepass { entity.insert(DepthPrepass); } if normal_prepass { entity.insert(NormalPrepass); } if motion_vector_prepass { entity.insert(MotionVectorPrepass); } if deferred_prepass { entity.insert(DeferredPrepass); } ``` to this: ``` let mut entity = commands.get_or_spawn(entity); if depth_prepass { entity = entity.insert(DepthPrepass); } if normal_prepass { entity = entity.insert(NormalPrepass); } if motion_vector_prepass { entity = entity.insert(MotionVectorPrepass); } if deferred_prepass { entity.insert(DeferredPrepass); } ``` as can be seen in several of the example code updates here. There will probably also be instances where mutable `EntityCommands` vars no longer need to be mutable.
		
			
				
	
	
		
			571 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			571 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
//! Demonstrates animation blending with animation graphs.
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//!
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//! The animation graph is shown on screen. You can change the weights of the
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//! playing animations by clicking and dragging left or right within the nodes.
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#[cfg(not(target_arch = "wasm32"))]
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use std::{fs::File, path::Path};
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use bevy::{
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    animation::animate_targets,
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    color::palettes::{
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        basic::WHITE,
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        css::{ANTIQUE_WHITE, DARK_GREEN},
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    },
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    prelude::*,
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    ui::RelativeCursorPosition,
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};
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use argh::FromArgs;
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#[cfg(not(target_arch = "wasm32"))]
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use bevy::asset::io::file::FileAssetReader;
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#[cfg(not(target_arch = "wasm32"))]
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use bevy::tasks::IoTaskPool;
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#[cfg(not(target_arch = "wasm32"))]
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use ron::ser::PrettyConfig;
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/// Where to find the serialized animation graph.
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static ANIMATION_GRAPH_PATH: &str = "animation_graphs/Fox.animgraph.ron";
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/// The indices of the nodes containing animation clips in the graph.
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static CLIP_NODE_INDICES: [u32; 3] = [2, 3, 4];
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/// The help text in the upper left corner.
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static HELP_TEXT: &str = "Click and drag an animation clip node to change its weight";
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/// The node widgets in the UI.
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static NODE_TYPES: [NodeType; 5] = [
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    NodeType::Clip(ClipNode::new("Idle", 0)),
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    NodeType::Clip(ClipNode::new("Walk", 1)),
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    NodeType::Blend("Root"),
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    NodeType::Blend("Blend\n0.5"),
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    NodeType::Clip(ClipNode::new("Run", 2)),
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];
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/// The positions of the node widgets in the UI.
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///
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/// These are in the same order as [`NODE_TYPES`] above.
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static NODE_RECTS: [NodeRect; 5] = [
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    NodeRect::new(10.00, 10.00, 97.64, 48.41),
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    NodeRect::new(10.00, 78.41, 97.64, 48.41),
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    NodeRect::new(286.08, 78.41, 97.64, 48.41),
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    NodeRect::new(148.04, 44.20, 97.64, 48.41),
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    NodeRect::new(10.00, 146.82, 97.64, 48.41),
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];
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/// The positions of the horizontal lines in the UI.
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static HORIZONTAL_LINES: [Line; 6] = [
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    Line::new(107.64, 34.21, 20.20),
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    Line::new(107.64, 102.61, 20.20),
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    Line::new(107.64, 171.02, 158.24),
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    Line::new(127.84, 68.41, 20.20),
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    Line::new(245.68, 68.41, 20.20),
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    Line::new(265.88, 102.61, 20.20),
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];
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/// The positions of the vertical lines in the UI.
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static VERTICAL_LINES: [Line; 2] = [
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    Line::new(127.83, 34.21, 68.40),
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    Line::new(265.88, 68.41, 102.61),
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];
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/// Initializes the app.
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fn main() {
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    #[cfg(not(target_arch = "wasm32"))]
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    let args: Args = argh::from_env();
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    #[cfg(target_arch = "wasm32")]
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    let args = Args::from_args(&[], &[]).unwrap();
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    App::new()
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        .add_plugins(DefaultPlugins.set(WindowPlugin {
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            primary_window: Some(Window {
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                title: "Bevy Animation Graph Example".into(),
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                ..default()
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            }),
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            ..default()
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        }))
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        .add_systems(Startup, (setup_assets, setup_scene, setup_ui))
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        .add_systems(Update, init_animations.before(animate_targets))
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        .add_systems(
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            Update,
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            (handle_weight_drag, update_ui, sync_weights).chain(),
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        )
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        .insert_resource(args)
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        .insert_resource(AmbientLight {
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            color: WHITE.into(),
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            brightness: 100.0,
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        })
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        .run();
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}
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/// Demonstrates animation blending with animation graphs
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#[derive(FromArgs, Resource)]
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struct Args {
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    /// disables loading of the animation graph asset from disk
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    #[argh(switch)]
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    no_load: bool,
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    /// regenerates the asset file; implies `--no-load`
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    #[argh(switch)]
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    save: bool,
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}
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/// The [`AnimationGraph`] asset, which specifies how the animations are to
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/// be blended together.
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#[derive(Clone, Resource)]
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struct ExampleAnimationGraph(Handle<AnimationGraph>);
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/// The current weights of the three playing animations.
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#[derive(Component)]
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struct ExampleAnimationWeights {
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    /// The weights of the three playing animations.
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    weights: [f32; 3],
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}
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/// Initializes the scene.
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fn setup_assets(
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    mut commands: Commands,
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    mut asset_server: ResMut<AssetServer>,
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    mut animation_graphs: ResMut<Assets<AnimationGraph>>,
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    args: Res<Args>,
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) {
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    // Create or load the assets.
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    if args.no_load || args.save {
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        setup_assets_programmatically(
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            &mut commands,
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            &mut asset_server,
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            &mut animation_graphs,
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            args.save,
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        );
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    } else {
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        setup_assets_via_serialized_animation_graph(&mut commands, &mut asset_server);
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    }
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}
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fn setup_ui(mut commands: Commands) {
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    setup_help_text(&mut commands);
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    setup_node_rects(&mut commands);
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    setup_node_lines(&mut commands);
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}
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/// Creates the assets programmatically, including the animation graph.
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/// Optionally saves them to disk if `save` is present (corresponding to the
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/// `--save` option).
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fn setup_assets_programmatically(
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    commands: &mut Commands,
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    asset_server: &mut AssetServer,
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    animation_graphs: &mut Assets<AnimationGraph>,
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    _save: bool,
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) {
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    // Create the nodes.
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    let mut animation_graph = AnimationGraph::new();
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    let blend_node = animation_graph.add_blend(0.5, animation_graph.root);
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    animation_graph.add_clip(
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        asset_server.load(GltfAssetLabel::Animation(0).from_asset("models/animated/Fox.glb")),
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        1.0,
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        animation_graph.root,
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    );
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    animation_graph.add_clip(
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        asset_server.load(GltfAssetLabel::Animation(1).from_asset("models/animated/Fox.glb")),
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        1.0,
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        blend_node,
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    );
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    animation_graph.add_clip(
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        asset_server.load(GltfAssetLabel::Animation(2).from_asset("models/animated/Fox.glb")),
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        1.0,
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        blend_node,
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    );
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    // If asked to save, do so.
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    #[cfg(not(target_arch = "wasm32"))]
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    if _save {
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        let animation_graph = animation_graph.clone();
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        IoTaskPool::get()
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            .spawn(async move {
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                let mut animation_graph_writer = File::create(Path::join(
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                    &FileAssetReader::get_base_path(),
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                    Path::join(Path::new("assets"), Path::new(ANIMATION_GRAPH_PATH)),
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                ))
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                .expect("Failed to open the animation graph asset");
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                ron::ser::to_writer_pretty(
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                    &mut animation_graph_writer,
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                    &animation_graph,
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                    PrettyConfig::default(),
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                )
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                .expect("Failed to serialize the animation graph");
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            })
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            .detach();
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    }
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    // Add the graph.
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    let handle = animation_graphs.add(animation_graph);
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    // Save the assets in a resource.
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    commands.insert_resource(ExampleAnimationGraph(handle));
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}
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fn setup_assets_via_serialized_animation_graph(
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    commands: &mut Commands,
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    asset_server: &mut AssetServer,
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) {
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    commands.insert_resource(ExampleAnimationGraph(
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        asset_server.load(ANIMATION_GRAPH_PATH),
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    ));
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}
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/// Spawns the animated fox.
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fn setup_scene(
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    mut commands: Commands,
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    asset_server: Res<AssetServer>,
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    mut meshes: ResMut<Assets<Mesh>>,
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    mut materials: ResMut<Assets<StandardMaterial>>,
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) {
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    commands.spawn(Camera3dBundle {
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        transform: Transform::from_xyz(-10.0, 5.0, 13.0).looking_at(Vec3::new(0., 1., 0.), Vec3::Y),
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        ..default()
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    });
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    commands.spawn(PointLightBundle {
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        point_light: PointLight {
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            intensity: 10_000_000.0,
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            shadows_enabled: true,
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            ..default()
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        },
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        transform: Transform::from_xyz(-4.0, 8.0, 13.0),
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        ..default()
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    });
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    commands.spawn(SceneBundle {
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        scene: asset_server.load(GltfAssetLabel::Scene(0).from_asset("models/animated/Fox.glb")),
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        transform: Transform::from_scale(Vec3::splat(0.07)),
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        ..default()
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    });
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    // Ground
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    commands.spawn(PbrBundle {
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        mesh: meshes.add(Circle::new(7.0)),
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        material: materials.add(Color::srgb(0.3, 0.5, 0.3)),
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        transform: Transform::from_rotation(Quat::from_rotation_x(-std::f32::consts::FRAC_PI_2)),
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        ..default()
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    });
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}
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/// Places the help text at the top left of the window.
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fn setup_help_text(commands: &mut Commands) {
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    commands.spawn(TextBundle {
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        text: Text::from_section(HELP_TEXT, TextStyle::default()),
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        style: Style {
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            position_type: PositionType::Absolute,
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            top: Val::Px(12.0),
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            left: Val::Px(12.0),
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            ..default()
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        },
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        ..default()
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    });
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}
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/// Initializes the node UI widgets.
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fn setup_node_rects(commands: &mut Commands) {
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    for (node_rect, node_type) in NODE_RECTS.iter().zip(NODE_TYPES.iter()) {
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        let node_string = match *node_type {
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            NodeType::Clip(ref clip) => clip.text,
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            NodeType::Blend(text) => text,
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        };
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        let text = commands
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            .spawn(TextBundle {
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                text: Text::from_section(
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                    node_string,
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                    TextStyle {
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                        font_size: 16.0,
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                        color: ANTIQUE_WHITE.into(),
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                        ..default()
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                    },
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                )
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                .with_justify(JustifyText::Center),
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                ..default()
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            })
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            .id();
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        let container = {
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            let mut container = commands.spawn((
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                NodeBundle {
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                    style: Style {
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                        position_type: PositionType::Absolute,
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                        bottom: Val::Px(node_rect.bottom),
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                        left: Val::Px(node_rect.left),
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                        height: Val::Px(node_rect.height),
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                        width: Val::Px(node_rect.width),
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                        align_items: AlignItems::Center,
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                        justify_items: JustifyItems::Center,
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                        align_content: AlignContent::Center,
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                        justify_content: JustifyContent::Center,
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                        ..default()
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                    },
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                    border_color: WHITE.into(),
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                    ..default()
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                },
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                Outline::new(Val::Px(1.), Val::ZERO, Color::WHITE),
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            ));
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            if let NodeType::Clip(ref clip) = node_type {
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                container = container.insert((
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                    Interaction::None,
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                    RelativeCursorPosition::default(),
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                    (*clip).clone(),
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                ));
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            }
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            container.id()
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        };
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        // Create the background color.
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        if let NodeType::Clip(_) = node_type {
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            let background = commands
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                .spawn(NodeBundle {
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                    style: Style {
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                        position_type: PositionType::Absolute,
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                        top: Val::Px(0.),
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                        left: Val::Px(0.),
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                        height: Val::Px(node_rect.height),
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                        width: Val::Px(node_rect.width),
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                        ..default()
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                    },
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                    background_color: DARK_GREEN.into(),
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                    ..default()
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                })
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                .id();
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            commands.entity(container).add_child(background);
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        }
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        commands.entity(container).add_child(text);
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    }
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}
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/// Creates boxes for the horizontal and vertical lines.
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///
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/// This is a bit hacky: it uses 1-pixel-wide and 1-pixel-high boxes to draw
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/// vertical and horizontal lines, respectively.
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fn setup_node_lines(commands: &mut Commands) {
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    for line in &HORIZONTAL_LINES {
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        commands.spawn(NodeBundle {
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            style: Style {
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                position_type: PositionType::Absolute,
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                bottom: Val::Px(line.bottom),
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                left: Val::Px(line.left),
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                height: Val::Px(0.0),
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                width: Val::Px(line.length),
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                border: UiRect::bottom(Val::Px(1.0)),
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                ..default()
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            },
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            border_color: WHITE.into(),
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            ..default()
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        });
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    }
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    for line in &VERTICAL_LINES {
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        commands.spawn(NodeBundle {
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            style: Style {
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                position_type: PositionType::Absolute,
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                bottom: Val::Px(line.bottom),
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                left: Val::Px(line.left),
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                height: Val::Px(line.length),
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                width: Val::Px(0.0),
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                border: UiRect::left(Val::Px(1.0)),
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                ..default()
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            },
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            border_color: WHITE.into(),
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            ..default()
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        });
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    }
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}
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/// Attaches the animation graph to the scene, and plays all three animations.
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fn init_animations(
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    mut commands: Commands,
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    mut query: Query<(Entity, &mut AnimationPlayer)>,
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    animation_graph: Res<ExampleAnimationGraph>,
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    mut done: Local<bool>,
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) {
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    if *done {
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        return;
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    }
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    for (entity, mut player) in query.iter_mut() {
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        commands.entity(entity).insert((
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            animation_graph.0.clone(),
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            ExampleAnimationWeights::default(),
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        ));
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        for &node_index in &CLIP_NODE_INDICES {
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            player.play(node_index.into()).repeat();
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        }
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        *done = true;
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    }
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}
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/// Read cursor position relative to clip nodes, allowing the user to change weights
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/// when dragging the node UI widgets.
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fn handle_weight_drag(
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    mut interaction_query: Query<(&Interaction, &RelativeCursorPosition, &ClipNode)>,
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    mut animation_weights_query: Query<&mut ExampleAnimationWeights>,
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) {
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    for (interaction, relative_cursor, clip_node) in &mut interaction_query {
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        if !matches!(*interaction, Interaction::Pressed) {
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            continue;
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        }
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        let Some(pos) = relative_cursor.normalized else {
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            continue;
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        };
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        for mut animation_weights in animation_weights_query.iter_mut() {
 | 
						|
            animation_weights.weights[clip_node.index] = pos.x.clamp(0., 1.);
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
// Updates the UI based on the weights that the user has chosen.
 | 
						|
fn update_ui(
 | 
						|
    mut text_query: Query<&mut Text>,
 | 
						|
    mut background_query: Query<&mut Style, Without<Text>>,
 | 
						|
    container_query: Query<(&Children, &ClipNode)>,
 | 
						|
    animation_weights_query: Query<&ExampleAnimationWeights, Changed<ExampleAnimationWeights>>,
 | 
						|
) {
 | 
						|
    for animation_weights in animation_weights_query.iter() {
 | 
						|
        for (children, clip_node) in &container_query {
 | 
						|
            // Draw the green background color to visually indicate the weight.
 | 
						|
            let mut bg_iter = background_query.iter_many_mut(children);
 | 
						|
            if let Some(mut style) = bg_iter.fetch_next() {
 | 
						|
                // All nodes are the same width, so `NODE_RECTS[0]` is as good as any other.
 | 
						|
                style.width =
 | 
						|
                    Val::Px(NODE_RECTS[0].width * animation_weights.weights[clip_node.index]);
 | 
						|
            }
 | 
						|
 | 
						|
            // Update the node labels with the current weights.
 | 
						|
            let mut text_iter = text_query.iter_many_mut(children);
 | 
						|
            if let Some(mut text) = text_iter.fetch_next() {
 | 
						|
                text.sections[0].value = format!(
 | 
						|
                    "{}\n{:.2}",
 | 
						|
                    clip_node.text, animation_weights.weights[clip_node.index]
 | 
						|
                );
 | 
						|
            }
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
/// Takes the weights that were set in the UI and assigns them to the actual
 | 
						|
/// playing animation.
 | 
						|
fn sync_weights(mut query: Query<(&mut AnimationPlayer, &ExampleAnimationWeights)>) {
 | 
						|
    for (mut animation_player, animation_weights) in query.iter_mut() {
 | 
						|
        for (&animation_node_index, &animation_weight) in CLIP_NODE_INDICES
 | 
						|
            .iter()
 | 
						|
            .zip(animation_weights.weights.iter())
 | 
						|
        {
 | 
						|
            // If the animation happens to be no longer active, restart it.
 | 
						|
            if !animation_player.animation_is_playing(animation_node_index.into()) {
 | 
						|
                animation_player.play(animation_node_index.into());
 | 
						|
            }
 | 
						|
 | 
						|
            // Set the weight.
 | 
						|
            if let Some(active_animation) =
 | 
						|
                animation_player.animation_mut(animation_node_index.into())
 | 
						|
            {
 | 
						|
                active_animation.set_weight(animation_weight);
 | 
						|
            }
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
/// An on-screen representation of a node.
 | 
						|
#[derive(Debug)]
 | 
						|
struct NodeRect {
 | 
						|
    /// The number of pixels that this rectangle is from the left edge of the
 | 
						|
    /// window.
 | 
						|
    left: f32,
 | 
						|
    /// The number of pixels that this rectangle is from the bottom edge of the
 | 
						|
    /// window.
 | 
						|
    bottom: f32,
 | 
						|
    /// The width of this rectangle in pixels.
 | 
						|
    width: f32,
 | 
						|
    /// The height of this rectangle in pixels.
 | 
						|
    height: f32,
 | 
						|
}
 | 
						|
 | 
						|
/// Either a straight horizontal or a straight vertical line on screen.
 | 
						|
///
 | 
						|
/// The line starts at (`left`, `bottom`) and goes either right (if the line is
 | 
						|
/// horizontal) or down (if the line is vertical).
 | 
						|
struct Line {
 | 
						|
    /// The number of pixels that the start of this line is from the left edge
 | 
						|
    /// of the screen.
 | 
						|
    left: f32,
 | 
						|
    /// The number of pixels that the start of this line is from the bottom edge
 | 
						|
    /// of the screen.
 | 
						|
    bottom: f32,
 | 
						|
    /// The length of the line.
 | 
						|
    length: f32,
 | 
						|
}
 | 
						|
 | 
						|
/// The type of each node in the UI: either a clip node or a blend node.
 | 
						|
enum NodeType {
 | 
						|
    /// A clip node, which specifies an animation.
 | 
						|
    Clip(ClipNode),
 | 
						|
    /// A blend node with no animation and a string label.
 | 
						|
    Blend(&'static str),
 | 
						|
}
 | 
						|
 | 
						|
/// The label for the UI representation of a clip node.
 | 
						|
#[derive(Clone, Component)]
 | 
						|
struct ClipNode {
 | 
						|
    /// The string label of the node.
 | 
						|
    text: &'static str,
 | 
						|
    /// Which of the three animations this UI widget represents.
 | 
						|
    index: usize,
 | 
						|
}
 | 
						|
 | 
						|
impl Default for ExampleAnimationWeights {
 | 
						|
    fn default() -> Self {
 | 
						|
        Self { weights: [1.0; 3] }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
impl ClipNode {
 | 
						|
    /// Creates a new [`ClipNodeText`] from a label and the animation index.
 | 
						|
    const fn new(text: &'static str, index: usize) -> Self {
 | 
						|
        Self { text, index }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
impl NodeRect {
 | 
						|
    /// Creates a new [`NodeRect`] from the lower-left corner and size.
 | 
						|
    ///
 | 
						|
    /// Note that node rectangles are anchored in the *lower*-left corner. The
 | 
						|
    /// `bottom` parameter specifies vertical distance from the *bottom* of the
 | 
						|
    /// window.
 | 
						|
    const fn new(left: f32, bottom: f32, width: f32, height: f32) -> NodeRect {
 | 
						|
        NodeRect {
 | 
						|
            left,
 | 
						|
            bottom,
 | 
						|
            width,
 | 
						|
            height,
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
impl Line {
 | 
						|
    /// Creates a new [`Line`], either horizontal or vertical.
 | 
						|
    ///
 | 
						|
    /// Note that the line's start point is anchored in the lower-*left* corner,
 | 
						|
    /// and that the `length` extends either to the right or downward.
 | 
						|
    const fn new(left: f32, bottom: f32, length: f32) -> Self {
 | 
						|
        Self {
 | 
						|
            left,
 | 
						|
            bottom,
 | 
						|
            length,
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 |