 ddbfa48711
			
		
	
	
		ddbfa48711
		
			
		
	
	
	
	
		
			
			# Objective
The `QueryParIter::for_each_mut` function is required when doing
parallel iteration with mutable queries.
This results in an unfortunate stutter:
`query.par_iter_mut().par_for_each_mut()` ('mut' is repeated).
## Solution
- Make `for_each` compatible with mutable queries, and deprecate
`for_each_mut`. In order to prevent `for_each` from being called
multiple times in parallel, we take ownership of the QueryParIter.
---
## Changelog
- `QueryParIter::for_each` is now compatible with mutable queries.
`for_each_mut` has been deprecated as it is now redundant.
## Migration Guide
The method `QueryParIter::for_each_mut` has been deprecated and is no
longer functional. Use `for_each` instead, which now supports mutable
queries.
```rust
// Before:
query.par_iter_mut().for_each_mut(|x| ...);
// After:
query.par_iter_mut().for_each(|x| ...);
```
The method `QueryParIter::for_each` now takes ownership of the
`QueryParIter`, rather than taking a shared reference.
```rust
// Before:
let par_iter = my_query.par_iter().batching_strategy(my_batching_strategy);
par_iter.for_each(|x| {
    // ...Do stuff with x...
    par_iter.for_each(|y| {
        // ...Do nested stuff with y...
    });
});
// After:
my_query.par_iter().batching_strategy(my_batching_strategy).for_each(|x| {
    // ...Do stuff with x...
    my_query.par_iter().batching_strategy(my_batching_strategy).for_each(|y| {
        // ...Do nested stuff with y...
    });
});
```
		
	
			
		
			
				
	
	
		
			616 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
			
		
		
	
	
			616 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			Rust
		
	
	
	
	
	
| //! Animation for the game engine Bevy
 | |
| 
 | |
| #![warn(missing_docs)]
 | |
| #![allow(clippy::type_complexity)]
 | |
| 
 | |
| use std::ops::Deref;
 | |
| use std::time::Duration;
 | |
| 
 | |
| use bevy_app::{App, Plugin, PostUpdate};
 | |
| use bevy_asset::{AddAsset, Assets, Handle};
 | |
| use bevy_core::Name;
 | |
| use bevy_ecs::prelude::*;
 | |
| use bevy_hierarchy::{Children, Parent};
 | |
| use bevy_math::{Quat, Vec3};
 | |
| use bevy_reflect::{Reflect, TypeUuid};
 | |
| use bevy_render::mesh::morph::MorphWeights;
 | |
| use bevy_time::Time;
 | |
| use bevy_transform::{prelude::Transform, TransformSystem};
 | |
| use bevy_utils::{tracing::warn, HashMap};
 | |
| 
 | |
| #[allow(missing_docs)]
 | |
| pub mod prelude {
 | |
|     #[doc(hidden)]
 | |
|     pub use crate::{
 | |
|         AnimationClip, AnimationPlayer, AnimationPlugin, EntityPath, Keyframes, VariableCurve,
 | |
|     };
 | |
| }
 | |
| 
 | |
| /// List of keyframes for one of the attribute of a [`Transform`].
 | |
| #[derive(Reflect, Clone, Debug)]
 | |
| pub enum Keyframes {
 | |
|     /// Keyframes for rotation.
 | |
|     Rotation(Vec<Quat>),
 | |
|     /// Keyframes for translation.
 | |
|     Translation(Vec<Vec3>),
 | |
|     /// Keyframes for scale.
 | |
|     Scale(Vec<Vec3>),
 | |
|     /// Keyframes for morph target weights.
 | |
|     ///
 | |
|     /// Note that in `.0`, each contiguous `target_count` values is a single
 | |
|     /// keyframe representing the weight values at given keyframe.
 | |
|     ///
 | |
|     /// This follows the [glTF design].
 | |
|     ///
 | |
|     /// [glTF design]: https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#animations
 | |
|     Weights(Vec<f32>),
 | |
| }
 | |
| 
 | |
| /// Describes how an attribute of a [`Transform`] or [`MorphWeights`] should be animated.
 | |
| ///
 | |
| /// `keyframe_timestamps` and `keyframes` should have the same length.
 | |
| #[derive(Reflect, Clone, Debug)]
 | |
| pub struct VariableCurve {
 | |
|     /// Timestamp for each of the keyframes.
 | |
|     pub keyframe_timestamps: Vec<f32>,
 | |
|     /// List of the keyframes.
 | |
|     pub keyframes: Keyframes,
 | |
| }
 | |
| 
 | |
| /// Path to an entity, with [`Name`]s. Each entity in a path must have a name.
 | |
| #[derive(Reflect, Clone, Debug, Hash, PartialEq, Eq, Default)]
 | |
| pub struct EntityPath {
 | |
|     /// Parts of the path
 | |
|     pub parts: Vec<Name>,
 | |
| }
 | |
| 
 | |
| /// A list of [`VariableCurve`], and the [`EntityPath`] to which they apply.
 | |
| #[derive(Reflect, Clone, TypeUuid, Debug, Default)]
 | |
| #[uuid = "d81b7179-0448-4eb0-89fe-c067222725bf"]
 | |
| pub struct AnimationClip {
 | |
|     curves: Vec<Vec<VariableCurve>>,
 | |
|     paths: HashMap<EntityPath, usize>,
 | |
|     duration: f32,
 | |
| }
 | |
| 
 | |
| impl AnimationClip {
 | |
|     #[inline]
 | |
|     /// [`VariableCurve`]s for each bone. Indexed by the bone ID.
 | |
|     pub fn curves(&self) -> &Vec<Vec<VariableCurve>> {
 | |
|         &self.curves
 | |
|     }
 | |
| 
 | |
|     /// Gets the curves for a bone.
 | |
|     ///
 | |
|     /// Returns `None` if the bone is invalid.
 | |
|     #[inline]
 | |
|     pub fn get_curves(&self, bone_id: usize) -> Option<&'_ Vec<VariableCurve>> {
 | |
|         self.curves.get(bone_id)
 | |
|     }
 | |
| 
 | |
|     /// Gets the curves by it's [`EntityPath`].
 | |
|     ///
 | |
|     /// Returns `None` if the bone is invalid.
 | |
|     #[inline]
 | |
|     pub fn get_curves_by_path(&self, path: &EntityPath) -> Option<&'_ Vec<VariableCurve>> {
 | |
|         self.paths.get(path).and_then(|id| self.curves.get(*id))
 | |
|     }
 | |
| 
 | |
|     /// Duration of the clip, represented in seconds
 | |
|     #[inline]
 | |
|     pub fn duration(&self) -> f32 {
 | |
|         self.duration
 | |
|     }
 | |
| 
 | |
|     /// Add a [`VariableCurve`] to an [`EntityPath`].
 | |
|     pub fn add_curve_to_path(&mut self, path: EntityPath, curve: VariableCurve) {
 | |
|         // Update the duration of the animation by this curve duration if it's longer
 | |
|         self.duration = self
 | |
|             .duration
 | |
|             .max(*curve.keyframe_timestamps.last().unwrap_or(&0.0));
 | |
|         if let Some(bone_id) = self.paths.get(&path) {
 | |
|             self.curves[*bone_id].push(curve);
 | |
|         } else {
 | |
|             let idx = self.curves.len();
 | |
|             self.curves.push(vec![curve]);
 | |
|             self.paths.insert(path, idx);
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /// Whether this animation clip can run on entity with given [`Name`].
 | |
|     pub fn compatible_with(&self, name: &Name) -> bool {
 | |
|         self.paths.keys().all(|path| &path.parts[0] == name)
 | |
|     }
 | |
| }
 | |
| 
 | |
| #[derive(Reflect)]
 | |
| struct PlayingAnimation {
 | |
|     repeat: bool,
 | |
|     speed: f32,
 | |
|     elapsed: f32,
 | |
|     animation_clip: Handle<AnimationClip>,
 | |
|     path_cache: Vec<Vec<Option<Entity>>>,
 | |
| }
 | |
| 
 | |
| impl Default for PlayingAnimation {
 | |
|     fn default() -> Self {
 | |
|         Self {
 | |
|             repeat: false,
 | |
|             speed: 1.0,
 | |
|             elapsed: 0.0,
 | |
|             animation_clip: Default::default(),
 | |
|             path_cache: Vec::new(),
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| /// An animation that is being faded out as part of a transition
 | |
| struct AnimationTransition {
 | |
|     /// The current weight. Starts at 1.0 and goes to 0.0 during the fade-out.
 | |
|     current_weight: f32,
 | |
|     /// How much to decrease `current_weight` per second
 | |
|     weight_decline_per_sec: f32,
 | |
|     /// The animation that is being faded out
 | |
|     animation: PlayingAnimation,
 | |
| }
 | |
| 
 | |
| /// Animation controls
 | |
| #[derive(Component, Default, Reflect)]
 | |
| #[reflect(Component)]
 | |
| pub struct AnimationPlayer {
 | |
|     paused: bool,
 | |
| 
 | |
|     animation: PlayingAnimation,
 | |
| 
 | |
|     // List of previous animations we're currently transitioning away from.
 | |
|     // Usually this is empty, when transitioning between animations, there is
 | |
|     // one entry. When another animation transition happens while a transition
 | |
|     // is still ongoing, then there can be more than one entry.
 | |
|     // Once a transition is finished, it will be automatically removed from the list
 | |
|     #[reflect(ignore)]
 | |
|     transitions: Vec<AnimationTransition>,
 | |
| }
 | |
| 
 | |
| impl AnimationPlayer {
 | |
|     /// Start playing an animation, resetting state of the player
 | |
|     /// This will use a linear blending between the previous and the new animation to make a smooth transition
 | |
|     pub fn start(&mut self, handle: Handle<AnimationClip>) -> &mut Self {
 | |
|         self.animation = PlayingAnimation {
 | |
|             animation_clip: handle,
 | |
|             ..Default::default()
 | |
|         };
 | |
| 
 | |
|         // We want a hard transition.
 | |
|         // In case any previous transitions are still playing, stop them
 | |
|         self.transitions.clear();
 | |
| 
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Start playing an animation, resetting state of the player
 | |
|     /// This will use a linear blending between the previous and the new animation to make a smooth transition
 | |
|     pub fn start_with_transition(
 | |
|         &mut self,
 | |
|         handle: Handle<AnimationClip>,
 | |
|         transition_duration: Duration,
 | |
|     ) -> &mut Self {
 | |
|         let mut animation = PlayingAnimation {
 | |
|             animation_clip: handle,
 | |
|             ..Default::default()
 | |
|         };
 | |
|         std::mem::swap(&mut animation, &mut self.animation);
 | |
| 
 | |
|         // Add the current transition. If other transitions are still ongoing,
 | |
|         // this will keep those transitions running and cause a transition between
 | |
|         // the output of that previous transition to the new animation.
 | |
|         self.transitions.push(AnimationTransition {
 | |
|             current_weight: 1.0,
 | |
|             weight_decline_per_sec: 1.0 / transition_duration.as_secs_f32(),
 | |
|             animation,
 | |
|         });
 | |
| 
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Start playing an animation, resetting state of the player, unless the requested animation is already playing.
 | |
|     /// If `transition_duration` is set, this will use a linear blending
 | |
|     /// between the previous and the new animation to make a smooth transition
 | |
|     pub fn play(&mut self, handle: Handle<AnimationClip>) -> &mut Self {
 | |
|         if self.animation.animation_clip != handle || self.is_paused() {
 | |
|             self.start(handle);
 | |
|         }
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Start playing an animation, resetting state of the player, unless the requested animation is already playing.
 | |
|     /// This will use a linear blending between the previous and the new animation to make a smooth transition
 | |
|     pub fn play_with_transition(
 | |
|         &mut self,
 | |
|         handle: Handle<AnimationClip>,
 | |
|         transition_duration: Duration,
 | |
|     ) -> &mut Self {
 | |
|         if self.animation.animation_clip != handle || self.is_paused() {
 | |
|             self.start_with_transition(handle, transition_duration);
 | |
|         }
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Set the animation to repeat
 | |
|     pub fn repeat(&mut self) -> &mut Self {
 | |
|         self.animation.repeat = true;
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Stop the animation from repeating
 | |
|     pub fn stop_repeating(&mut self) -> &mut Self {
 | |
|         self.animation.repeat = false;
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Pause the animation
 | |
|     pub fn pause(&mut self) {
 | |
|         self.paused = true;
 | |
|     }
 | |
| 
 | |
|     /// Unpause the animation
 | |
|     pub fn resume(&mut self) {
 | |
|         self.paused = false;
 | |
|     }
 | |
| 
 | |
|     /// Is the animation paused
 | |
|     pub fn is_paused(&self) -> bool {
 | |
|         self.paused
 | |
|     }
 | |
| 
 | |
|     /// Speed of the animation playback
 | |
|     pub fn speed(&self) -> f32 {
 | |
|         self.animation.speed
 | |
|     }
 | |
| 
 | |
|     /// Set the speed of the animation playback
 | |
|     pub fn set_speed(&mut self, speed: f32) -> &mut Self {
 | |
|         self.animation.speed = speed;
 | |
|         self
 | |
|     }
 | |
| 
 | |
|     /// Time elapsed playing the animation
 | |
|     pub fn elapsed(&self) -> f32 {
 | |
|         self.animation.elapsed
 | |
|     }
 | |
| 
 | |
|     /// Seek to a specific time in the animation
 | |
|     pub fn set_elapsed(&mut self, elapsed: f32) -> &mut Self {
 | |
|         self.animation.elapsed = elapsed;
 | |
|         self
 | |
|     }
 | |
| }
 | |
| 
 | |
| fn entity_from_path(
 | |
|     root: Entity,
 | |
|     path: &EntityPath,
 | |
|     children: &Query<&Children>,
 | |
|     names: &Query<&Name>,
 | |
|     path_cache: &mut Vec<Option<Entity>>,
 | |
| ) -> Option<Entity> {
 | |
|     // PERF: finding the target entity can be optimised
 | |
|     let mut current_entity = root;
 | |
|     path_cache.resize(path.parts.len(), None);
 | |
|     // Ignore the first name, it is the root node which we already have
 | |
|     for (idx, part) in path.parts.iter().enumerate().skip(1) {
 | |
|         let mut found = false;
 | |
|         let children = children.get(current_entity).ok()?;
 | |
|         if let Some(cached) = path_cache[idx] {
 | |
|             if children.contains(&cached) {
 | |
|                 if let Ok(name) = names.get(cached) {
 | |
|                     if name == part {
 | |
|                         current_entity = cached;
 | |
|                         found = true;
 | |
|                     }
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|         if !found {
 | |
|             for child in children.deref() {
 | |
|                 if let Ok(name) = names.get(*child) {
 | |
|                     if name == part {
 | |
|                         // Found a children with the right name, continue to the next part
 | |
|                         current_entity = *child;
 | |
|                         path_cache[idx] = Some(*child);
 | |
|                         found = true;
 | |
|                         break;
 | |
|                     }
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|         if !found {
 | |
|             warn!("Entity not found for path {:?} on part {:?}", path, part);
 | |
|             return None;
 | |
|         }
 | |
|     }
 | |
|     Some(current_entity)
 | |
| }
 | |
| 
 | |
| /// Verify that there are no ancestors of a given entity that have an [`AnimationPlayer`].
 | |
| fn verify_no_ancestor_player(
 | |
|     player_parent: Option<&Parent>,
 | |
|     parents: &Query<(Option<With<AnimationPlayer>>, Option<&Parent>)>,
 | |
| ) -> bool {
 | |
|     let Some(mut current) = player_parent.map(Parent::get) else { return true };
 | |
|     loop {
 | |
|         let Ok((maybe_player, parent)) = parents.get(current) else { return true };
 | |
|         if maybe_player.is_some() {
 | |
|             return false;
 | |
|         }
 | |
|         if let Some(parent) = parent {
 | |
|             current = parent.get();
 | |
|         } else {
 | |
|             return true;
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| /// System that will play all animations, using any entity with a [`AnimationPlayer`]
 | |
| /// and a [`Handle<AnimationClip>`] as an animation root
 | |
| #[allow(clippy::too_many_arguments)]
 | |
| pub fn animation_player(
 | |
|     time: Res<Time>,
 | |
|     animations: Res<Assets<AnimationClip>>,
 | |
|     children: Query<&Children>,
 | |
|     names: Query<&Name>,
 | |
|     transforms: Query<&mut Transform>,
 | |
|     morphs: Query<&mut MorphWeights>,
 | |
|     parents: Query<(Option<With<AnimationPlayer>>, Option<&Parent>)>,
 | |
|     mut animation_players: Query<(Entity, Option<&Parent>, &mut AnimationPlayer)>,
 | |
| ) {
 | |
|     animation_players
 | |
|         .par_iter_mut()
 | |
|         .for_each(|(root, maybe_parent, mut player)| {
 | |
|             update_transitions(&mut player, &time);
 | |
|             run_animation_player(
 | |
|                 root,
 | |
|                 player,
 | |
|                 &time,
 | |
|                 &animations,
 | |
|                 &names,
 | |
|                 &transforms,
 | |
|                 &morphs,
 | |
|                 maybe_parent,
 | |
|                 &parents,
 | |
|                 &children,
 | |
|             );
 | |
|         });
 | |
| }
 | |
| 
 | |
| #[allow(clippy::too_many_arguments)]
 | |
| fn run_animation_player(
 | |
|     root: Entity,
 | |
|     mut player: Mut<AnimationPlayer>,
 | |
|     time: &Time,
 | |
|     animations: &Assets<AnimationClip>,
 | |
|     names: &Query<&Name>,
 | |
|     transforms: &Query<&mut Transform>,
 | |
|     morphs: &Query<&mut MorphWeights>,
 | |
|     maybe_parent: Option<&Parent>,
 | |
|     parents: &Query<(Option<With<AnimationPlayer>>, Option<&Parent>)>,
 | |
|     children: &Query<&Children>,
 | |
| ) {
 | |
|     let paused = player.paused;
 | |
|     // Continue if paused unless the `AnimationPlayer` was changed
 | |
|     // This allow the animation to still be updated if the player.elapsed field was manually updated in pause
 | |
|     if paused && !player.is_changed() {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     // Apply the main animation
 | |
|     apply_animation(
 | |
|         1.0,
 | |
|         &mut player.animation,
 | |
|         paused,
 | |
|         root,
 | |
|         time,
 | |
|         animations,
 | |
|         names,
 | |
|         transforms,
 | |
|         morphs,
 | |
|         maybe_parent,
 | |
|         parents,
 | |
|         children,
 | |
|     );
 | |
| 
 | |
|     // Apply any potential fade-out transitions from previous animations
 | |
|     for AnimationTransition {
 | |
|         current_weight,
 | |
|         animation,
 | |
|         ..
 | |
|     } in &mut player.transitions
 | |
|     {
 | |
|         apply_animation(
 | |
|             *current_weight,
 | |
|             animation,
 | |
|             paused,
 | |
|             root,
 | |
|             time,
 | |
|             animations,
 | |
|             names,
 | |
|             transforms,
 | |
|             morphs,
 | |
|             maybe_parent,
 | |
|             parents,
 | |
|             children,
 | |
|         );
 | |
|     }
 | |
| }
 | |
| 
 | |
| /// Update `weights` based on weights in `keyframes` at index `key_index`
 | |
| /// with a linear interpolation on `key_lerp`.
 | |
| ///
 | |
| /// # Panics
 | |
| ///
 | |
| /// When `key_index * target_count` is larger than `keyframes`
 | |
| ///
 | |
| /// This happens when `keyframes` is not formatted as described in
 | |
| /// [`Keyframes::Weights`]. A possible cause is [`AnimationClip`] not being
 | |
| /// meant to be used for the [`MorphWeights`] of the entity it's being applied to.
 | |
| fn lerp_morph_weights(weights: &mut [f32], key_lerp: f32, keyframes: &[f32], key_index: usize) {
 | |
|     let target_count = weights.len();
 | |
|     let start = target_count * key_index;
 | |
|     let end = target_count * (key_index + 1);
 | |
| 
 | |
|     let zipped = weights.iter_mut().zip(&keyframes[start..end]);
 | |
|     for (morph_weight, keyframe) in zipped {
 | |
|         let minus_lerp = 1.0 - key_lerp;
 | |
|         *morph_weight = (*morph_weight * minus_lerp) + (keyframe * key_lerp);
 | |
|     }
 | |
| }
 | |
| 
 | |
| #[allow(clippy::too_many_arguments)]
 | |
| fn apply_animation(
 | |
|     weight: f32,
 | |
|     animation: &mut PlayingAnimation,
 | |
|     paused: bool,
 | |
|     root: Entity,
 | |
|     time: &Time,
 | |
|     animations: &Assets<AnimationClip>,
 | |
|     names: &Query<&Name>,
 | |
|     transforms: &Query<&mut Transform>,
 | |
|     morphs: &Query<&mut MorphWeights>,
 | |
|     maybe_parent: Option<&Parent>,
 | |
|     parents: &Query<(Option<With<AnimationPlayer>>, Option<&Parent>)>,
 | |
|     children: &Query<&Children>,
 | |
| ) {
 | |
|     if let Some(animation_clip) = animations.get(&animation.animation_clip) {
 | |
|         if !paused {
 | |
|             animation.elapsed += time.delta_seconds() * animation.speed;
 | |
|         }
 | |
|         let mut elapsed = animation.elapsed;
 | |
|         if animation.repeat {
 | |
|             elapsed %= animation_clip.duration;
 | |
|         }
 | |
|         if elapsed < 0.0 {
 | |
|             elapsed += animation_clip.duration;
 | |
|         }
 | |
|         if animation.path_cache.len() != animation_clip.paths.len() {
 | |
|             animation.path_cache = vec![Vec::new(); animation_clip.paths.len()];
 | |
|         }
 | |
|         if !verify_no_ancestor_player(maybe_parent, parents) {
 | |
|             warn!("Animation player on {:?} has a conflicting animation player on an ancestor. Cannot safely animate.", root);
 | |
|             return;
 | |
|         }
 | |
| 
 | |
|         for (path, bone_id) in &animation_clip.paths {
 | |
|             let cached_path = &mut animation.path_cache[*bone_id];
 | |
|             let curves = animation_clip.get_curves(*bone_id).unwrap();
 | |
|             let Some(target) = entity_from_path(root, path, children, names, cached_path) else { continue };
 | |
|             // SAFETY: The verify_no_ancestor_player check above ensures that two animation players cannot alias
 | |
|             // any of their descendant Transforms.
 | |
|             //
 | |
|             // The system scheduler prevents any other system from mutating Transforms at the same time,
 | |
|             // so the only way this fetch can alias is if two AnimationPlayers are targeting the same bone.
 | |
|             // This can only happen if there are two or more AnimationPlayers are ancestors to the same
 | |
|             // entities. By verifying that there is no other AnimationPlayer in the ancestors of a
 | |
|             // running AnimationPlayer before animating any entity, this fetch cannot alias.
 | |
|             //
 | |
|             // This means only the AnimationPlayers closest to the root of the hierarchy will be able
 | |
|             // to run their animation. Any players in the children or descendants will log a warning
 | |
|             // and do nothing.
 | |
|             let Ok(mut transform) = (unsafe { transforms.get_unchecked(target) }) else { continue };
 | |
|             let mut morphs = unsafe { morphs.get_unchecked(target) };
 | |
|             for curve in curves {
 | |
|                 // Some curves have only one keyframe used to set a transform
 | |
|                 if curve.keyframe_timestamps.len() == 1 {
 | |
|                     match &curve.keyframes {
 | |
|                         Keyframes::Rotation(keyframes) => {
 | |
|                             transform.rotation = transform.rotation.slerp(keyframes[0], weight);
 | |
|                         }
 | |
|                         Keyframes::Translation(keyframes) => {
 | |
|                             transform.translation =
 | |
|                                 transform.translation.lerp(keyframes[0], weight);
 | |
|                         }
 | |
|                         Keyframes::Scale(keyframes) => {
 | |
|                             transform.scale = transform.scale.lerp(keyframes[0], weight);
 | |
|                         }
 | |
|                         Keyframes::Weights(keyframes) => {
 | |
|                             if let Ok(morphs) = &mut morphs {
 | |
|                                 lerp_morph_weights(morphs.weights_mut(), weight, keyframes, 0);
 | |
|                             }
 | |
|                         }
 | |
|                     }
 | |
|                     continue;
 | |
|                 }
 | |
| 
 | |
|                 // Find the current keyframe
 | |
|                 // PERF: finding the current keyframe can be optimised
 | |
|                 let step_start = match curve
 | |
|                     .keyframe_timestamps
 | |
|                     .binary_search_by(|probe| probe.partial_cmp(&elapsed).unwrap())
 | |
|                 {
 | |
|                     Ok(n) if n >= curve.keyframe_timestamps.len() - 1 => continue, // this curve is finished
 | |
|                     Ok(i) => i,
 | |
|                     Err(0) => continue, // this curve isn't started yet
 | |
|                     Err(n) if n > curve.keyframe_timestamps.len() - 1 => continue, // this curve is finished
 | |
|                     Err(i) => i - 1,
 | |
|                 };
 | |
|                 let ts_start = curve.keyframe_timestamps[step_start];
 | |
|                 let ts_end = curve.keyframe_timestamps[step_start + 1];
 | |
|                 let lerp = (elapsed - ts_start) / (ts_end - ts_start);
 | |
| 
 | |
|                 // Apply the keyframe
 | |
|                 match &curve.keyframes {
 | |
|                     Keyframes::Rotation(keyframes) => {
 | |
|                         let rot_start = keyframes[step_start];
 | |
|                         let mut rot_end = keyframes[step_start + 1];
 | |
|                         // Choose the smallest angle for the rotation
 | |
|                         if rot_end.dot(rot_start) < 0.0 {
 | |
|                             rot_end = -rot_end;
 | |
|                         }
 | |
|                         // Rotations are using a spherical linear interpolation
 | |
|                         let rot = rot_start.normalize().slerp(rot_end.normalize(), lerp);
 | |
|                         transform.rotation = transform.rotation.slerp(rot, weight);
 | |
|                     }
 | |
|                     Keyframes::Translation(keyframes) => {
 | |
|                         let translation_start = keyframes[step_start];
 | |
|                         let translation_end = keyframes[step_start + 1];
 | |
|                         let result = translation_start.lerp(translation_end, lerp);
 | |
|                         transform.translation = transform.translation.lerp(result, weight);
 | |
|                     }
 | |
|                     Keyframes::Scale(keyframes) => {
 | |
|                         let scale_start = keyframes[step_start];
 | |
|                         let scale_end = keyframes[step_start + 1];
 | |
|                         let result = scale_start.lerp(scale_end, lerp);
 | |
|                         transform.scale = transform.scale.lerp(result, weight);
 | |
|                     }
 | |
|                     Keyframes::Weights(keyframes) => {
 | |
|                         if let Ok(morphs) = &mut morphs {
 | |
|                             lerp_morph_weights(morphs.weights_mut(), weight, keyframes, step_start);
 | |
|                         }
 | |
|                     }
 | |
|                 }
 | |
|             }
 | |
|         }
 | |
|     }
 | |
| }
 | |
| 
 | |
| fn update_transitions(player: &mut AnimationPlayer, time: &Time) {
 | |
|     player.transitions.retain_mut(|animation| {
 | |
|         animation.current_weight -= animation.weight_decline_per_sec * time.delta_seconds();
 | |
|         animation.current_weight > 0.0
 | |
|     });
 | |
| }
 | |
| 
 | |
| /// Adds animation support to an app
 | |
| #[derive(Default)]
 | |
| pub struct AnimationPlugin;
 | |
| 
 | |
| impl Plugin for AnimationPlugin {
 | |
|     fn build(&self, app: &mut App) {
 | |
|         app.add_asset::<AnimationClip>()
 | |
|             .register_asset_reflect::<AnimationClip>()
 | |
|             .register_type::<AnimationPlayer>()
 | |
|             .register_type::<PlayingAnimation>()
 | |
|             .add_systems(
 | |
|                 PostUpdate,
 | |
|                 animation_player.before(TransformSystem::TransformPropagate),
 | |
|             );
 | |
|     }
 | |
| }
 |