mirror of
https://github.com/bevyengine/bevy
synced 2024-12-30 06:53:13 +00:00
8b636f32cf
# Objective In the animation example, there is the code `.add_systems(Update, init_animations.before(animate_targets))`, where `animate_targets` is added to the `PostUpdate` in the `AnimationPlugin`. Therefore, the `.before(animate_targets)` here is ineffective and should be removed.
556 lines
17 KiB
Rust
556 lines
17 KiB
Rust
//! Demonstrates animation blending with animation graphs.
|
|
//!
|
|
//! The animation graph is shown on screen. You can change the weights of the
|
|
//! playing animations by clicking and dragging left or right within the nodes.
|
|
|
|
use bevy::{
|
|
color::palettes::{
|
|
basic::WHITE,
|
|
css::{ANTIQUE_WHITE, DARK_GREEN},
|
|
},
|
|
prelude::*,
|
|
ui::RelativeCursorPosition,
|
|
};
|
|
|
|
use argh::FromArgs;
|
|
|
|
#[cfg(not(target_arch = "wasm32"))]
|
|
use {
|
|
bevy::{asset::io::file::FileAssetReader, tasks::IoTaskPool},
|
|
ron::ser::PrettyConfig,
|
|
std::{fs::File, path::Path},
|
|
};
|
|
|
|
/// Where to find the serialized animation graph.
|
|
static ANIMATION_GRAPH_PATH: &str = "animation_graphs/Fox.animgraph.ron";
|
|
|
|
/// The indices of the nodes containing animation clips in the graph.
|
|
static CLIP_NODE_INDICES: [u32; 3] = [2, 3, 4];
|
|
|
|
/// The help text in the upper left corner.
|
|
static HELP_TEXT: &str = "Click and drag an animation clip node to change its weight";
|
|
|
|
/// The node widgets in the UI.
|
|
static NODE_TYPES: [NodeType; 5] = [
|
|
NodeType::Clip(ClipNode::new("Idle", 0)),
|
|
NodeType::Clip(ClipNode::new("Walk", 1)),
|
|
NodeType::Blend("Root"),
|
|
NodeType::Blend("Blend\n0.5"),
|
|
NodeType::Clip(ClipNode::new("Run", 2)),
|
|
];
|
|
|
|
/// The positions of the node widgets in the UI.
|
|
///
|
|
/// These are in the same order as [`NODE_TYPES`] above.
|
|
static NODE_RECTS: [NodeRect; 5] = [
|
|
NodeRect::new(10.00, 10.00, 97.64, 48.41),
|
|
NodeRect::new(10.00, 78.41, 97.64, 48.41),
|
|
NodeRect::new(286.08, 78.41, 97.64, 48.41),
|
|
NodeRect::new(148.04, 112.61, 97.64, 48.41), // was 44.20
|
|
NodeRect::new(10.00, 146.82, 97.64, 48.41),
|
|
];
|
|
|
|
/// The positions of the horizontal lines in the UI.
|
|
static HORIZONTAL_LINES: [Line; 6] = [
|
|
Line::new(107.64, 34.21, 158.24),
|
|
Line::new(107.64, 102.61, 20.20),
|
|
Line::new(107.64, 171.02, 20.20),
|
|
Line::new(127.84, 136.82, 20.20),
|
|
Line::new(245.68, 136.82, 20.20),
|
|
Line::new(265.88, 102.61, 20.20),
|
|
];
|
|
|
|
/// The positions of the vertical lines in the UI.
|
|
static VERTICAL_LINES: [Line; 2] = [
|
|
Line::new(127.83, 102.61, 68.40),
|
|
Line::new(265.88, 34.21, 102.61),
|
|
];
|
|
|
|
/// Initializes the app.
|
|
fn main() {
|
|
#[cfg(not(target_arch = "wasm32"))]
|
|
let args: Args = argh::from_env();
|
|
#[cfg(target_arch = "wasm32")]
|
|
let args = Args::from_args(&[], &[]).unwrap();
|
|
|
|
App::new()
|
|
.add_plugins(DefaultPlugins.set(WindowPlugin {
|
|
primary_window: Some(Window {
|
|
title: "Bevy Animation Graph Example".into(),
|
|
..default()
|
|
}),
|
|
..default()
|
|
}))
|
|
.add_systems(Startup, (setup_assets, setup_scene, setup_ui))
|
|
.add_systems(Update, init_animations)
|
|
.add_systems(
|
|
Update,
|
|
(handle_weight_drag, update_ui, sync_weights).chain(),
|
|
)
|
|
.insert_resource(args)
|
|
.insert_resource(AmbientLight {
|
|
color: WHITE.into(),
|
|
brightness: 100.0,
|
|
})
|
|
.run();
|
|
}
|
|
|
|
/// Demonstrates animation blending with animation graphs
|
|
#[derive(FromArgs, Resource)]
|
|
struct Args {
|
|
/// disables loading of the animation graph asset from disk
|
|
#[argh(switch)]
|
|
no_load: bool,
|
|
/// regenerates the asset file; implies `--no-load`
|
|
#[argh(switch)]
|
|
save: bool,
|
|
}
|
|
|
|
/// The [`AnimationGraph`] asset, which specifies how the animations are to
|
|
/// be blended together.
|
|
#[derive(Clone, Resource)]
|
|
struct ExampleAnimationGraph(Handle<AnimationGraph>);
|
|
|
|
/// The current weights of the three playing animations.
|
|
#[derive(Component)]
|
|
struct ExampleAnimationWeights {
|
|
/// The weights of the three playing animations.
|
|
weights: [f32; 3],
|
|
}
|
|
|
|
/// Initializes the scene.
|
|
fn setup_assets(
|
|
mut commands: Commands,
|
|
mut asset_server: ResMut<AssetServer>,
|
|
mut animation_graphs: ResMut<Assets<AnimationGraph>>,
|
|
args: Res<Args>,
|
|
) {
|
|
// Create or load the assets.
|
|
if args.no_load || args.save {
|
|
setup_assets_programmatically(
|
|
&mut commands,
|
|
&mut asset_server,
|
|
&mut animation_graphs,
|
|
args.save,
|
|
);
|
|
} else {
|
|
setup_assets_via_serialized_animation_graph(&mut commands, &mut asset_server);
|
|
}
|
|
}
|
|
|
|
fn setup_ui(mut commands: Commands) {
|
|
setup_help_text(&mut commands);
|
|
setup_node_rects(&mut commands);
|
|
setup_node_lines(&mut commands);
|
|
}
|
|
|
|
/// Creates the assets programmatically, including the animation graph.
|
|
/// Optionally saves them to disk if `save` is present (corresponding to the
|
|
/// `--save` option).
|
|
fn setup_assets_programmatically(
|
|
commands: &mut Commands,
|
|
asset_server: &mut AssetServer,
|
|
animation_graphs: &mut Assets<AnimationGraph>,
|
|
_save: bool,
|
|
) {
|
|
// Create the nodes.
|
|
let mut animation_graph = AnimationGraph::new();
|
|
let blend_node = animation_graph.add_blend(0.5, animation_graph.root);
|
|
animation_graph.add_clip(
|
|
asset_server.load(GltfAssetLabel::Animation(0).from_asset("models/animated/Fox.glb")),
|
|
1.0,
|
|
animation_graph.root,
|
|
);
|
|
animation_graph.add_clip(
|
|
asset_server.load(GltfAssetLabel::Animation(1).from_asset("models/animated/Fox.glb")),
|
|
1.0,
|
|
blend_node,
|
|
);
|
|
animation_graph.add_clip(
|
|
asset_server.load(GltfAssetLabel::Animation(2).from_asset("models/animated/Fox.glb")),
|
|
1.0,
|
|
blend_node,
|
|
);
|
|
|
|
// If asked to save, do so.
|
|
#[cfg(not(target_arch = "wasm32"))]
|
|
if _save {
|
|
let animation_graph = animation_graph.clone();
|
|
|
|
IoTaskPool::get()
|
|
.spawn(async move {
|
|
let mut animation_graph_writer = File::create(Path::join(
|
|
&FileAssetReader::get_base_path(),
|
|
Path::join(Path::new("assets"), Path::new(ANIMATION_GRAPH_PATH)),
|
|
))
|
|
.expect("Failed to open the animation graph asset");
|
|
ron::ser::to_writer_pretty(
|
|
&mut animation_graph_writer,
|
|
&animation_graph,
|
|
PrettyConfig::default(),
|
|
)
|
|
.expect("Failed to serialize the animation graph");
|
|
})
|
|
.detach();
|
|
}
|
|
|
|
// Add the graph.
|
|
let handle = animation_graphs.add(animation_graph);
|
|
|
|
// Save the assets in a resource.
|
|
commands.insert_resource(ExampleAnimationGraph(handle));
|
|
}
|
|
|
|
fn setup_assets_via_serialized_animation_graph(
|
|
commands: &mut Commands,
|
|
asset_server: &mut AssetServer,
|
|
) {
|
|
commands.insert_resource(ExampleAnimationGraph(
|
|
asset_server.load(ANIMATION_GRAPH_PATH),
|
|
));
|
|
}
|
|
|
|
/// Spawns the animated fox.
|
|
fn setup_scene(
|
|
mut commands: Commands,
|
|
asset_server: Res<AssetServer>,
|
|
mut meshes: ResMut<Assets<Mesh>>,
|
|
mut materials: ResMut<Assets<StandardMaterial>>,
|
|
) {
|
|
commands.spawn((
|
|
Camera3d::default(),
|
|
Transform::from_xyz(-10.0, 5.0, 13.0).looking_at(Vec3::new(0., 1., 0.), Vec3::Y),
|
|
));
|
|
|
|
commands.spawn((
|
|
PointLight {
|
|
intensity: 10_000_000.0,
|
|
shadows_enabled: true,
|
|
..default()
|
|
},
|
|
Transform::from_xyz(-4.0, 8.0, 13.0),
|
|
));
|
|
|
|
commands.spawn((
|
|
SceneRoot(
|
|
asset_server.load(GltfAssetLabel::Scene(0).from_asset("models/animated/Fox.glb")),
|
|
),
|
|
Transform::from_scale(Vec3::splat(0.07)),
|
|
));
|
|
|
|
// Ground
|
|
|
|
commands.spawn((
|
|
Mesh3d(meshes.add(Circle::new(7.0))),
|
|
MeshMaterial3d(materials.add(Color::srgb(0.3, 0.5, 0.3))),
|
|
Transform::from_rotation(Quat::from_rotation_x(-std::f32::consts::FRAC_PI_2)),
|
|
));
|
|
}
|
|
|
|
/// Places the help text at the top left of the window.
|
|
fn setup_help_text(commands: &mut Commands) {
|
|
commands.spawn((
|
|
Text::new(HELP_TEXT),
|
|
Node {
|
|
position_type: PositionType::Absolute,
|
|
top: Val::Px(12.0),
|
|
left: Val::Px(12.0),
|
|
..default()
|
|
},
|
|
));
|
|
}
|
|
|
|
/// Initializes the node UI widgets.
|
|
fn setup_node_rects(commands: &mut Commands) {
|
|
for (node_rect, node_type) in NODE_RECTS.iter().zip(NODE_TYPES.iter()) {
|
|
let node_string = match *node_type {
|
|
NodeType::Clip(ref clip) => clip.text,
|
|
NodeType::Blend(text) => text,
|
|
};
|
|
|
|
let text = commands
|
|
.spawn((
|
|
Text::new(node_string),
|
|
TextFont {
|
|
font_size: 16.0,
|
|
..default()
|
|
},
|
|
TextColor(ANTIQUE_WHITE.into()),
|
|
TextLayout::new_with_justify(JustifyText::Center),
|
|
))
|
|
.id();
|
|
|
|
let container = {
|
|
let mut container = commands.spawn((
|
|
Node {
|
|
position_type: PositionType::Absolute,
|
|
bottom: Val::Px(node_rect.bottom),
|
|
left: Val::Px(node_rect.left),
|
|
height: Val::Px(node_rect.height),
|
|
width: Val::Px(node_rect.width),
|
|
align_items: AlignItems::Center,
|
|
justify_items: JustifyItems::Center,
|
|
align_content: AlignContent::Center,
|
|
justify_content: JustifyContent::Center,
|
|
..default()
|
|
},
|
|
BorderColor(WHITE.into()),
|
|
Outline::new(Val::Px(1.), Val::ZERO, Color::WHITE),
|
|
));
|
|
|
|
if let NodeType::Clip(ref clip) = node_type {
|
|
container.insert((
|
|
Interaction::None,
|
|
RelativeCursorPosition::default(),
|
|
(*clip).clone(),
|
|
));
|
|
}
|
|
|
|
container.id()
|
|
};
|
|
|
|
// Create the background color.
|
|
if let NodeType::Clip(_) = node_type {
|
|
let background = commands
|
|
.spawn((
|
|
Node {
|
|
position_type: PositionType::Absolute,
|
|
top: Val::Px(0.),
|
|
left: Val::Px(0.),
|
|
height: Val::Px(node_rect.height),
|
|
width: Val::Px(node_rect.width),
|
|
..default()
|
|
},
|
|
BackgroundColor(DARK_GREEN.into()),
|
|
))
|
|
.id();
|
|
|
|
commands.entity(container).add_child(background);
|
|
}
|
|
|
|
commands.entity(container).add_child(text);
|
|
}
|
|
}
|
|
|
|
/// Creates boxes for the horizontal and vertical lines.
|
|
///
|
|
/// This is a bit hacky: it uses 1-pixel-wide and 1-pixel-high boxes to draw
|
|
/// vertical and horizontal lines, respectively.
|
|
fn setup_node_lines(commands: &mut Commands) {
|
|
for line in &HORIZONTAL_LINES {
|
|
commands.spawn((
|
|
Node {
|
|
position_type: PositionType::Absolute,
|
|
bottom: Val::Px(line.bottom),
|
|
left: Val::Px(line.left),
|
|
height: Val::Px(0.0),
|
|
width: Val::Px(line.length),
|
|
border: UiRect::bottom(Val::Px(1.0)),
|
|
..default()
|
|
},
|
|
BorderColor(WHITE.into()),
|
|
));
|
|
}
|
|
|
|
for line in &VERTICAL_LINES {
|
|
commands.spawn((
|
|
Node {
|
|
position_type: PositionType::Absolute,
|
|
bottom: Val::Px(line.bottom),
|
|
left: Val::Px(line.left),
|
|
height: Val::Px(line.length),
|
|
width: Val::Px(0.0),
|
|
border: UiRect::left(Val::Px(1.0)),
|
|
..default()
|
|
},
|
|
BorderColor(WHITE.into()),
|
|
));
|
|
}
|
|
}
|
|
|
|
/// Attaches the animation graph to the scene, and plays all three animations.
|
|
fn init_animations(
|
|
mut commands: Commands,
|
|
mut query: Query<(Entity, &mut AnimationPlayer)>,
|
|
animation_graph: Res<ExampleAnimationGraph>,
|
|
mut done: Local<bool>,
|
|
) {
|
|
if *done {
|
|
return;
|
|
}
|
|
|
|
for (entity, mut player) in query.iter_mut() {
|
|
commands.entity(entity).insert((
|
|
AnimationGraphHandle(animation_graph.0.clone()),
|
|
ExampleAnimationWeights::default(),
|
|
));
|
|
for &node_index in &CLIP_NODE_INDICES {
|
|
player.play(node_index.into()).repeat();
|
|
}
|
|
|
|
*done = true;
|
|
}
|
|
}
|
|
|
|
/// Read cursor position relative to clip nodes, allowing the user to change weights
|
|
/// when dragging the node UI widgets.
|
|
fn handle_weight_drag(
|
|
mut interaction_query: Query<(&Interaction, &RelativeCursorPosition, &ClipNode)>,
|
|
mut animation_weights_query: Query<&mut ExampleAnimationWeights>,
|
|
) {
|
|
for (interaction, relative_cursor, clip_node) in &mut interaction_query {
|
|
if !matches!(*interaction, Interaction::Pressed) {
|
|
continue;
|
|
}
|
|
|
|
let Some(pos) = relative_cursor.normalized else {
|
|
continue;
|
|
};
|
|
|
|
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 Node, 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 node) = bg_iter.fetch_next() {
|
|
// All nodes are the same width, so `NODE_RECTS[0]` is as good as any other.
|
|
node.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 = 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.is_playing_animation(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,
|
|
}
|
|
}
|
|
}
|