use std::time::Duration;
use bevy::prelude::*;
use crate::{EaseMethod, Lens, RepeatCount, RepeatStrategy, TweeningDirection};
/// The dynamic tweenable type.
///
/// When creating lists of tweenables, you will need to box them to create a
/// homogeneous array like so:
/// ```no_run
/// # use bevy::prelude::Transform;
/// # use bevy_tweening::{BoxedTweenable, Delay, Sequence, Tween};
/// #
/// # let delay: Delay = unimplemented!();
/// # let tween: Tween<Transform> = unimplemented!();
///
/// Sequence::new([Box::new(delay) as BoxedTweenable<Transform>, tween.into()]);
/// ```
///
/// When using your own [`Tweenable`] types, APIs will be easier to use if you
/// implement [`From`]:
/// ```no_run
/// # use std::time::Duration;
/// # use bevy::prelude::{Entity, EventWriter, Transform};
/// # use bevy_tweening::{BoxedTweenable, Sequence, Tweenable, TweenCompleted, TweenState};
/// #
/// # struct MyTweenable;
/// # impl Tweenable<Transform> for MyTweenable {
/// # fn duration(&self) -> Duration { unimplemented!() }
/// # fn set_progress(&mut self, progress: f32) { unimplemented!() }
/// # fn progress(&self) -> f32 { unimplemented!() }
/// # fn tick(&mut self, delta: Duration, target: &mut Transform, entity: Entity, event_writer: &mut EventWriter<TweenCompleted>) -> TweenState { unimplemented!() }
/// # fn times_completed(&self) -> u32 { unimplemented!() }
/// # fn rewind(&mut self) { unimplemented!() }
/// # }
///
/// Sequence::new([Box::new(MyTweenable) as BoxedTweenable<_>]);
///
/// // OR
///
/// Sequence::new([MyTweenable]);
///
/// impl From<MyTweenable> for BoxedTweenable<Transform> {
/// fn from(t: MyTweenable) -> Self {
/// Box::new(t)
/// }
/// }
/// ```
pub type BoxedTweenable<T> = Box<dyn Tweenable<T> + Send + Sync + 'static>;
/// Playback state of a [`Tweenable`].
///
/// This is returned by [`Tweenable::tick()`] to allow the caller to execute
/// some logic based on the updated state of the tweenable, like advanding a
/// sequence to its next child tweenable.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum TweenState {
/// The tweenable is still active, and did not reach its end state yet.
Active,
/// Animation reached its end state. The tweenable is idling at its latest
/// time.
///
/// Note that [`RepeatCount::Infinite`] tweenables never reach this state.
Completed,
}
/// Event raised when a tween completed.
///
/// This event is raised when a tween completed. When looping, this is raised
/// once per iteration. In case the animation direction changes
/// ([`RepeatStrategy::MirroredRepeat`]), an iteration corresponds to a single
/// progress from one endpoint to the other, whatever the direction. Therefore a
/// complete cycle start -> end -> start counts as 2 iterations and raises 2
/// events (one when reaching the end, one when reaching back the start).
///
/// # Note
///
/// The semantic is slightly different from [`TweenState::Completed`], which
/// indicates that the tweenable has finished ticking and do not need to be
/// updated anymore, a state which is never reached for looping animation. Here
/// the [`TweenCompleted`] event instead marks the end of a single loop
/// iteration.
#[derive(Copy, Clone)]
pub struct TweenCompleted {
/// The [`Entity`] the tween which completed and its animator are attached
/// to.
pub entity: Entity,
/// An opaque value set by the user when activating event raising, used to
/// identify the particular tween which raised this event. The value is
/// passed unmodified from a call to [`with_completed_event()`]
/// or [`set_completed_event()`].
///
/// [`with_completed_event()`]: Tween::with_completed_event
/// [`set_completed_event()`]: Tween::set_completed_event
pub user_data: u64,
}
#[derive(Debug)]
struct AnimClock {
elapsed: Duration,
duration: Duration,
times_completed: u32,
total_duration: TotalDuration,
strategy: RepeatStrategy,
}
impl AnimClock {
fn new(duration: Duration) -> Self {
Self {
elapsed: Duration::ZERO,
duration,
total_duration: compute_total_duration(duration, RepeatCount::default()),
times_completed: 0,
strategy: RepeatStrategy::default(),
}
}
fn record_completions(&mut self, times_completed: u32) {
self.times_completed = self.times_completed.saturating_add(times_completed);
}
fn tick(&mut self, tick: Duration) -> u32 {
let duration = self.duration.as_nanos();
let before = self.elapsed.as_nanos() / duration;
self.elapsed = self.elapsed.saturating_add(tick);
if let TotalDuration::Finite(duration) = self.total_duration {
self.elapsed = self.elapsed.min(duration);
}
(self.elapsed.as_nanos() / duration - before) as u32
}
fn set_progress(&mut self, progress: f32) {
self.elapsed = self.duration.mul_f32(progress.max(0.));
}
fn progress(&self) -> f32 {
self.elapsed.as_secs_f32() / self.duration.as_secs_f32()
}
fn state(&self) -> TweenState {
match self.total_duration {
TotalDuration::Finite(duration) => {
if self.elapsed >= duration {
TweenState::Completed
} else {
TweenState::Active
}
}
TotalDuration::Infinite => TweenState::Active,
}
}
fn reset(&mut self) {
self.times_completed = 0;
self.elapsed = Duration::ZERO;
}
}
#[derive(Debug)]
enum TotalDuration {
Finite(Duration),
Infinite,
}
fn compute_total_duration(duration: Duration, count: RepeatCount) -> TotalDuration {
match count {
RepeatCount::Finite(times) => TotalDuration::Finite(duration.saturating_mul(times)),
RepeatCount::For(duration) => TotalDuration::Finite(duration),
RepeatCount::Infinite => TotalDuration::Infinite,
}
}
/// An animatable entity, either a single [`Tween`] or a collection of them.
pub trait Tweenable<T>: Send + Sync {
/// Get the total duration of the animation.
///
/// This is always the duration of a single iteration, even when looping.
///
/// Note that for [`RepeatStrategy::MirroredRepeat`], this is the duration
/// of a single way, either from start to end or back from end to start.
/// The total "loop" duration start -> end -> start to reach back the
/// same state in this case is the double of the returned value.
fn duration(&self) -> Duration;
/// Set the current animation playback progress.
///
/// See [`progress()`] for details on the meaning.
///
/// [`progress()`]: Tweenable::progress
fn set_progress(&mut self, progress: f32);
/// Get the current progress in \[0:1\] of the animation.
///
/// While looping, the exact value `1.0` is never reached, since the
/// tweenable loops over to `0.0` immediately when it changes direction at
/// either endpoint. Upon completion, the tweenable always reports exactly
/// `1.0`.
fn progress(&self) -> f32;
/// Tick the animation, advancing it by the given delta time and mutating
/// the given target component or asset.
///
/// This returns [`TweenState::Active`] if the tweenable didn't reach its
/// final state yet (progress < `1.0`), or [`TweenState::Completed`] if
/// the tweenable completed this tick. Only non-looping tweenables return
/// a completed state, since looping ones continue forever.
///
/// Calling this method with a duration of [`Duration::ZERO`] is valid, and
/// updates the target to the current state of the tweenable without
/// actually modifying the tweenable state. This is useful after certain
/// operations like [`rewind()`] or [`set_progress()`] whose effect is
/// otherwise only visible on target on next frame.
///
/// [`rewind()`]: Tweenable::rewind
/// [`set_progress()`]: Tweenable::set_progress
fn tick(
&mut self,
delta: Duration,
target: &mut T,
entity: Entity,
event_writer: &mut EventWriter<TweenCompleted>,
) -> TweenState;
/// Get the number of times this tweenable completed.
///
/// For looping animations, this returns the number of times a single
/// playback was completed. In the case of
/// [`RepeatStrategy::MirroredRepeat`] this corresponds to a playback in
/// a single direction, so tweening from start to end and back to start
/// counts as two completed times (one forward, one backward).
fn times_completed(&self) -> u32;
/// Rewind the animation to its starting state.
///
/// Note that the starting state depends on the current direction. For
/// [`TweeningDirection::Forward`] this is the start point of the lens,
/// whereas for [`TweeningDirection::Backward`] this is the end one.
fn rewind(&mut self);
}
impl<T> From<Delay> for BoxedTweenable<T> {
fn from(d: Delay) -> Self {
Box::new(d)
}
}
impl<T: 'static> From<Sequence<T>> for BoxedTweenable<T> {
fn from(s: Sequence<T>) -> Self {
Box::new(s)
}
}
impl<T: 'static> From<Tracks<T>> for BoxedTweenable<T> {
fn from(t: Tracks<T>) -> Self {
Box::new(t)
}
}
impl<T: 'static> From<Tween<T>> for BoxedTweenable<T> {
fn from(t: Tween<T>) -> Self {
Box::new(t)
}
}
/// Type of a callback invoked when a [`Tween`] has completed.
///
/// See [`Tween::set_completed()`] for usage.
pub type CompletedCallback<T> = dyn Fn(Entity, &Tween<T>) + Send + Sync + 'static;
/// Single tweening animation instance.
pub struct Tween<T> {
ease_function: EaseMethod,
clock: AnimClock,
direction: TweeningDirection,
lens: Box<dyn Lens<T> + Send + Sync + 'static>,
on_completed: Option<Box<CompletedCallback<T>>>,
event_data: Option<u64>,
}
impl<T: 'static> Tween<T> {
/// Chain another [`Tweenable`] after this tween, making a [`Sequence`] with
/// the two.
///
/// # Example
/// ```
/// # use bevy_tweening::{lens::*, *};
/// # use bevy::math::*;
/// # use std::time::Duration;
/// let tween1 = Tween::new(
/// EaseFunction::QuadraticInOut,
/// Duration::from_secs_f32(1.0),
/// TransformPositionLens {
/// start: Vec3::ZERO,
/// end: Vec3::new(3.5, 0., 0.),
/// },
/// );
/// let tween2 = Tween::new(
/// EaseFunction::QuadraticInOut,
/// Duration::from_secs_f32(1.0),
/// TransformRotationLens {
/// start: Quat::IDENTITY,
/// end: Quat::from_rotation_x(90.0_f32.to_radians()),
/// },
/// );
/// let seq = tween1.then(tween2);
/// ```
#[must_use]
pub fn then(self, tween: impl Tweenable<T> + Send + Sync + 'static) -> Sequence<T> {
Sequence::with_capacity(2).then(self).then(tween)
}
}
impl<T> Tween<T> {
/// Create a new tween animation.
///
/// # Example
/// ```
/// # use bevy_tweening::{lens::*, *};
/// # use bevy::math::Vec3;
/// # use std::time::Duration;
/// let tween = Tween::new(
/// EaseFunction::QuadraticInOut,
/// Duration::from_secs_f32(1.0),
/// TransformPositionLens {
/// start: Vec3::ZERO,
/// end: Vec3::new(3.5, 0., 0.),
/// },
/// );
/// ```
#[must_use]
pub fn new<L>(ease_function: impl Into<EaseMethod>, duration: Duration, lens: L) -> Self
where
L: Lens<T> + Send + Sync + 'static,
{
Self {
ease_function: ease_function.into(),
clock: AnimClock::new(duration),
direction: TweeningDirection::Forward,
lens: Box::new(lens),
on_completed: None,
event_data: None,
}
}
/// Enable or disable raising a completed event.
///
/// If enabled, the tween will raise a [`TweenCompleted`] event when the
/// animation completed. This is similar to the [`set_completed()`]
/// callback, but uses Bevy events instead.
///
/// # Example
/// ```
/// # use bevy_tweening::{lens::*, *};
/// # use bevy::{ecs::event::EventReader, math::Vec3};
/// # use std::time::Duration;
/// let tween = Tween::new(
/// // [...]
/// # EaseFunction::QuadraticInOut,
/// # Duration::from_secs_f32(1.0),
/// # TransformPositionLens {
/// # start: Vec3::ZERO,
/// # end: Vec3::new(3.5, 0., 0.),
/// # },
/// )
/// .with_completed_event(42);
///
/// fn my_system(mut reader: EventReader<TweenCompleted>) {
/// for ev in reader.iter() {
/// assert_eq!(ev.user_data, 42);
/// println!("Entity {:?} raised TweenCompleted!", ev.entity);
/// }
/// }
/// ```
///
/// [`set_completed()`]: Tween::set_completed
#[must_use]
pub fn with_completed_event(mut self, user_data: u64) -> Self {
self.event_data = Some(user_data);
self
}
/// Set the playback direction of the tween.
///
/// The playback direction influences the mapping of the progress ratio (in
/// \[0:1\]) to the actual ratio passed to the lens.
/// [`TweeningDirection::Forward`] maps the `0` value of progress to the
/// `0` value of the lens ratio. Conversely, [`TweeningDirection::Backward`]
/// reverses the mapping, which effectively makes the tween play reversed,
/// going from end to start.
///
/// Changing the direction doesn't change any target state, nor any progress
/// of the tween. Only the direction of animation from this moment
/// potentially changes. To force a target state change, call
/// [`Tweenable::tick()`] with a zero delta (`Duration::ZERO`).
pub fn set_direction(&mut self, direction: TweeningDirection) {
self.direction = direction;
}
/// Set the playback direction of the tween.
///
/// See [`Tween::set_direction()`].
#[must_use]
pub fn with_direction(mut self, direction: TweeningDirection) -> Self {
self.direction = direction;
self
}
/// The current animation direction.
///
/// See [`TweeningDirection`] for details.
#[must_use]
pub fn direction(&self) -> TweeningDirection {
self.direction
}
/// Set the number of times to repeat the animation.
#[must_use]
pub fn with_repeat_count(mut self, count: RepeatCount) -> Self {
self.clock.total_duration = compute_total_duration(self.clock.duration, count);
self
}
/// Choose how the animation behaves upon a repetition.
#[must_use]
pub fn with_repeat_strategy(mut self, strategy: RepeatStrategy) -> Self {
self.clock.strategy = strategy;
self
}
/// Set a callback invoked when the animation completes.
///
/// The callback when invoked receives as parameters the [`Entity`] on which
/// the target and the animator are, as well as a reference to the
/// current [`Tween`].
///
/// Only non-looping tweenables can complete.
pub fn set_completed<C>(&mut self, callback: C)
where
C: Fn(Entity, &Self) + Send + Sync + 'static,
{
self.on_completed = Some(Box::new(callback));
}
/// Clear the callback invoked when the animation completes.
pub fn clear_completed(&mut self) {
self.on_completed = None;
}
/// Enable or disable raising a completed event.
///
/// If enabled, the tween will raise a [`TweenCompleted`] event when the
/// animation completed. This is similar to the [`set_completed()`]
/// callback, but uses Bevy events instead.
///
/// See [`with_completed_event()`] for details.
///
/// [`set_completed()`]: Tween::set_completed
/// [`with_completed_event()`]: Tween::with_completed_event
pub fn set_completed_event(&mut self, user_data: u64) {
self.event_data = Some(user_data);
}
/// Clear the event sent when the animation completes.
pub fn clear_completed_event(&mut self) {
self.event_data = None;
}
}
impl<T> Tweenable<T> for Tween<T> {
fn duration(&self) -> Duration {
self.clock.duration
}
fn set_progress(&mut self, progress: f32) {
self.clock.set_progress(progress);
}
fn progress(&self) -> f32 {
self.clock.progress()
}
fn tick(
&mut self,
delta: Duration,
target: &mut T,
entity: Entity,
event_writer: &mut EventWriter<TweenCompleted>,
) -> TweenState {
if self.clock.state() == TweenState::Completed {
return TweenState::Completed;
}
// Tick the animation clock
let times_completed = self.clock.tick(delta);
self.clock.record_completions(times_completed);
if self.clock.strategy == RepeatStrategy::MirroredRepeat && times_completed & 1 != 0 {
self.direction = !self.direction;
}
let progress = self.progress();
// Apply the lens, even if the animation finished, to ensure the state is
// consistent
let mut factor = progress;
if self.direction.is_backward() {
factor = 1. - factor;
}
let factor = self.ease_function.sample(factor);
self.lens.lerp(target, factor);
// If completed at least once this frame, notify the user
if times_completed > 0 {
if let Some(user_data) = &self.event_data {
event_writer.send(TweenCompleted {
entity,
user_data: *user_data,
});
}
if let Some(cb) = &self.on_completed {
cb(entity, self);
}
}
self.clock.state()
}
fn times_completed(&self) -> u32 {
self.clock.times_completed
}
fn rewind(&mut self) {
self.clock.reset();
}
}
/// A sequence of tweens played back in order one after the other.
pub struct Sequence<T> {
tweens: Vec<BoxedTweenable<T>>,
index: usize,
duration: Duration,
time: Duration,
times_completed: u32,
}
impl<T> Sequence<T> {
/// Create a new sequence of tweens.
///
/// This method panics if the input collection is empty.
#[must_use]
pub fn new(items: impl IntoIterator<Item = impl Into<BoxedTweenable<T>>>) -> Self {
let tweens: Vec<_> = items.into_iter().map(Into::into).collect();
assert!(!tweens.is_empty());
let duration = tweens
.iter()
.map(AsRef::as_ref)
.map(Tweenable::duration)
.sum();
Self {
tweens,
index: 0,
duration,
time: Duration::ZERO,
times_completed: 0,
}
}
/// Create a new sequence containing a single tween.
#[must_use]
pub fn from_single(tween: impl Tweenable<T> + Send + Sync + 'static) -> Self {
let duration = tween.duration();
let boxed: BoxedTweenable<T> = Box::new(tween);
Self {
tweens: vec![boxed],
index: 0,
duration,
time: Duration::ZERO,
times_completed: 0,
}
}
/// Create a new sequence with the specified capacity.
#[must_use]
pub fn with_capacity(capacity: usize) -> Self {
Self {
tweens: Vec::with_capacity(capacity),
index: 0,
duration: Duration::ZERO,
time: Duration::ZERO,
times_completed: 0,
}
}
/// Append a [`Tweenable`] to this sequence.
#[must_use]
pub fn then(mut self, tween: impl Tweenable<T> + Send + Sync + 'static) -> Self {
self.duration += tween.duration();
self.tweens.push(Box::new(tween));
self
}
/// Index of the current active tween in the sequence.
#[must_use]
pub fn index(&self) -> usize {
self.index.min(self.tweens.len() - 1)
}
/// Get the current active tween in the sequence.
#[must_use]
pub fn current(&self) -> &dyn Tweenable<T> {
self.tweens[self.index()].as_ref()
}
}
impl<T> Tweenable<T> for Sequence<T> {
fn duration(&self) -> Duration {
self.duration
}
fn set_progress(&mut self, progress: f32) {
self.times_completed = if progress >= 1. { 1 } else { 0 };
let progress = progress.clamp(0., 1.); // not looping
// Set the total sequence progress
let total_elapsed_secs = self.duration().as_secs_f64() * progress as f64;
self.time = Duration::from_secs_f64(total_elapsed_secs);
// Find which tween is active in the sequence
let mut accum_duration = 0.;
for index in 0..self.tweens.len() {
let tween = &mut self.tweens[index];
let tween_duration = tween.duration().as_secs_f64();
if total_elapsed_secs < accum_duration + tween_duration {
self.index = index;
let local_duration = total_elapsed_secs - accum_duration;
tween.set_progress((local_duration / tween_duration) as f32);
// TODO?? set progress of other tweens after that one to 0. ??
return;
}
tween.set_progress(1.); // ?? to prepare for next loop/rewind?
accum_duration += tween_duration;
}
// None found; sequence ended
self.index = self.tweens.len();
}
fn progress(&self) -> f32 {
self.time.as_secs_f32() / self.duration.as_secs_f32()
}
fn tick(
&mut self,
mut delta: Duration,
target: &mut T,
entity: Entity,
event_writer: &mut EventWriter<TweenCompleted>,
) -> TweenState {
self.time = (self.time + delta).min(self.duration);
while self.index < self.tweens.len() {
let tween = &mut self.tweens[self.index];
let tween_remaining = tween.duration().mul_f32(1.0 - tween.progress());
if let TweenState::Active = tween.tick(delta, target, entity, event_writer) {
return TweenState::Active;
}
tween.rewind();
delta -= tween_remaining;
self.index += 1;
}
self.times_completed = 1;
TweenState::Completed
}
fn times_completed(&self) -> u32 {
self.times_completed
}
fn rewind(&mut self) {
self.time = Duration::ZERO;
self.index = 0;
self.times_completed = 0;
for tween in &mut self.tweens {
// or only first?
tween.rewind();
}
}
}
/// A collection of [`Tweenable`] executing in parallel.
pub struct Tracks<T> {
tracks: Vec<BoxedTweenable<T>>,
duration: Duration,
time: Duration,
times_completed: u32,
}
impl<T> Tracks<T> {
/// Create a new [`Tracks`] from an iterator over a collection of
/// [`Tweenable`].
#[must_use]
pub fn new(items: impl IntoIterator<Item = impl Into<BoxedTweenable<T>>>) -> Self {
let tracks: Vec<_> = items.into_iter().map(Into::into).collect();
let duration = tracks
.iter()
.map(AsRef::as_ref)
.map(Tweenable::duration)
.max()
.unwrap();
Self {
tracks,
duration,
time: Duration::ZERO,
times_completed: 0,
}
}
}
impl<T> Tweenable<T> for Tracks<T> {
fn duration(&self) -> Duration {
self.duration
}
fn set_progress(&mut self, progress: f32) {
self.times_completed = if progress >= 1. { 1 } else { 0 }; // not looping
let progress = progress.clamp(0., 1.); // not looping
let time_secs = self.duration.as_secs_f64() * progress as f64;
self.time = Duration::from_secs_f64(time_secs);
for tweenable in &mut self.tracks {
let progress = time_secs / tweenable.duration().as_secs_f64();
tweenable.set_progress(progress as f32);
}
}
fn progress(&self) -> f32 {
self.time.as_secs_f32() / self.duration.as_secs_f32()
}
fn tick(
&mut self,
delta: Duration,
target: &mut T,
entity: Entity,
event_writer: &mut EventWriter<TweenCompleted>,
) -> TweenState {
self.time = (self.time + delta).min(self.duration);
let mut any_active = false;
for tweenable in &mut self.tracks {
let state = tweenable.tick(delta, target, entity, event_writer);
any_active = any_active || (state == TweenState::Active);
}
if any_active {
TweenState::Active
} else {
self.times_completed = 1;
TweenState::Completed
}
}
fn times_completed(&self) -> u32 {
self.times_completed
}
fn rewind(&mut self) {
self.time = Duration::ZERO;
self.times_completed = 0;
for tween in &mut self.tracks {
tween.rewind();
}
}
}
/// A time delay that doesn't animate anything.
///
/// This is generally useful for combining with other tweenables into sequences
/// and tracks, for example to delay the start of a tween in a track relative to
/// another track. The `menu` example (`examples/menu.rs`) uses this technique
/// to delay the animation of its buttons.
pub struct Delay {
timer: Timer,
}
impl Delay {
/// Create a new [`Delay`] with a given duration.
///
/// # Panics
///
/// Panics if the duration is zero.
#[must_use]
pub fn new(duration: Duration) -> Self {
assert!(!duration.is_zero());
Self {
timer: Timer::new(duration, false),
}
}
/// Chain another [`Tweenable`] after this tween, making a [`Sequence`] with
/// the two.
#[must_use]
pub fn then<T>(self, tween: impl Tweenable<T> + Send + Sync + 'static) -> Sequence<T> {
Sequence::with_capacity(2).then(self).then(tween)
}
}
impl<T> Tweenable<T> for Delay {
fn duration(&self) -> Duration {
self.timer.duration()
}
fn set_progress(&mut self, progress: f32) {
// need to reset() to clear finished() unfortunately
self.timer.reset();
self.timer.set_elapsed(Duration::from_secs_f64(
self.timer.duration().as_secs_f64() * progress as f64,
));
// set_elapsed() does not update finished() etc. which we rely on
self.timer.tick(Duration::ZERO);
}
fn progress(&self) -> f32 {
self.timer.percent()
}
fn tick(
&mut self,
delta: Duration,
_target: &mut T,
_entity: Entity,
_event_writer: &mut EventWriter<TweenCompleted>,
) -> TweenState {
self.timer.tick(delta);
if self.timer.finished() {
TweenState::Completed
} else {
TweenState::Active
}
}
fn times_completed(&self) -> u32 {
if self.timer.finished() {
1
} else {
0
}
}
fn rewind(&mut self) {
self.timer.reset();
}
}
#[cfg(test)]
mod tests {
use std::{
sync::{Arc, Mutex},
time::Duration,
};
use bevy::ecs::{event::Events, system::SystemState};
use crate::lens::*;
use super::*;
/// Utility to compare floating-point values with a tolerance.
fn abs_diff_eq(a: f32, b: f32, tol: f32) -> bool {
(a - b).abs() < tol
}
#[derive(Default, Copy, Clone)]
struct CallbackMonitor {
invoke_count: u64,
last_reported_count: u32,
}
#[test]
fn anim_clock_precision() {
let duration = Duration::from_millis(1);
let mut clock = AnimClock::new(duration);
clock.total_duration = TotalDuration::Infinite;
let test_ticks = [
Duration::from_micros(123),
Duration::from_millis(1),
Duration::from_secs_f32(1. / 24.),
Duration::from_secs_f32(1. / 30.),
Duration::from_secs_f32(1. / 60.),
Duration::from_secs_f32(1. / 120.),
Duration::from_secs_f32(1. / 144.),
Duration::from_secs_f32(1. / 240.),
];
let mut times_completed = 0;
let mut total_duration = Duration::ZERO;
for i in 0..10_000_000 {
let tick = test_ticks[i % test_ticks.len()];
times_completed += clock.tick(tick);
total_duration += tick;
}
assert_eq!(
(total_duration.as_secs_f64() / duration.as_secs_f64()) as u32,
times_completed
);
}
/// Test ticking of a single tween in isolation.
#[test]
fn tween_tick() {
for tweening_direction in &[TweeningDirection::Forward, TweeningDirection::Backward] {
for (count, strategy) in &[
(RepeatCount::Finite(1), RepeatStrategy::default()),
(RepeatCount::Infinite, RepeatStrategy::Repeat),
(RepeatCount::Finite(2), RepeatStrategy::Repeat),
(RepeatCount::Infinite, RepeatStrategy::MirroredRepeat),
(RepeatCount::Finite(2), RepeatStrategy::MirroredRepeat),
] {
println!(
"TweeningType: count={count:?} strategy={strategy:?} dir={tweening_direction:?}",
);
// Create a linear tween over 1 second
let mut tween = Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(1.0),
TransformPositionLens {
start: Vec3::ZERO,
end: Vec3::ONE,
},
)
.with_direction(*tweening_direction)
.with_repeat_count(*count)
.with_repeat_strategy(*strategy);
assert_eq!(tween.direction(), *tweening_direction);
assert!(tween.on_completed.is_none());
assert!(tween.event_data.is_none());
let dummy_entity = Entity::from_raw(42);
// Register callbacks to count started/ended events
let callback_monitor = Arc::new(Mutex::new(CallbackMonitor::default()));
let cb_mon_ptr = Arc::clone(&callback_monitor);
tween.set_completed(move |entity, tween| {
assert_eq!(dummy_entity, entity);
let mut cb_mon = cb_mon_ptr.lock().unwrap();
cb_mon.invoke_count += 1;
cb_mon.last_reported_count = tween.times_completed();
});
assert!(tween.on_completed.is_some());
assert!(tween.event_data.is_none());
assert_eq!(callback_monitor.lock().unwrap().invoke_count, 0);
// Activate event sending
const USER_DATA: u64 = 54789; // dummy
tween.set_completed_event(USER_DATA);
assert!(tween.event_data.is_some());
assert_eq!(tween.event_data.unwrap(), USER_DATA);
// Dummy world and event writer
let mut world = World::new();
world.insert_resource(Events::<TweenCompleted>::default());
let mut event_writer_system_state: SystemState<EventWriter<TweenCompleted>> =
SystemState::new(&mut world);
let mut event_reader_system_state: SystemState<EventReader<TweenCompleted>> =
SystemState::new(&mut world);
// Loop over 2.2 seconds, so greater than one ping-pong loop
let mut transform = Transform::default();
let tick_duration = Duration::from_secs_f32(0.2);
for i in 1..=11 {
// Calculate expected values
let (progress, times_completed, mut direction, expected_state, just_completed) =
match count {
RepeatCount::Finite(1) => {
let progress = (i as f32 * 0.2).min(1.0);
let times_completed = if i >= 5 { 1 } else { 0 };
let state = if i < 5 {
TweenState::Active
} else {
TweenState::Completed
};
let just_completed = i == 5;
(
progress,
times_completed,
TweeningDirection::Forward,
state,
just_completed,
)
}
RepeatCount::Finite(count) => {
let progress = (i as f32 * 0.2).min(1.0 * *count as f32);
if *strategy == RepeatStrategy::Repeat {
let times_completed = i / 5;
let just_completed = i % 5 == 0;
(
progress,
times_completed,
TweeningDirection::Forward,
if i < 10 {
TweenState::Active
} else {
TweenState::Completed
},
just_completed,
)
} else {
let i5 = i % 5;
let times_completed = i / 5;
let i10 = i % 10;
let direction = if i10 >= 5 {
TweeningDirection::Backward
} else {
TweeningDirection::Forward
};
let just_completed = i5 == 0;
(
progress,
times_completed,
direction,
if i < 10 {
TweenState::Active
} else {
TweenState::Completed
},
just_completed,
)
}
}
RepeatCount::Infinite => {
let progress = i as f32 * 0.2;
if *strategy == RepeatStrategy::Repeat {
let times_completed = i / 5;
let just_completed = i % 5 == 0;
(
progress,
times_completed,
TweeningDirection::Forward,
TweenState::Active,
just_completed,
)
} else {
let i5 = i % 5;
let times_completed = i / 5;
let i10 = i % 10;
let direction = if i10 >= 5 {
TweeningDirection::Backward
} else {
TweeningDirection::Forward
};
let just_completed = i5 == 0;
(
progress,
times_completed,
direction,
TweenState::Active,
just_completed,
)
}
}
RepeatCount::For(_) => panic!("Untested"),
};
let factor = if tweening_direction.is_backward() {
direction = !direction;
1. - progress
} else {
progress
};
let expected_translation = if direction.is_forward() {
Vec3::splat(progress)
} else {
Vec3::splat(1. - progress)
};
println!(
"Expected: progress={} factor={} times_completed={} direction={:?} state={:?} just_completed={} translation={:?}",
progress, factor, times_completed, direction, expected_state, just_completed, expected_translation
);
// Tick the tween
let actual_state = {
let mut event_writer = event_writer_system_state.get_mut(&mut world);
tween.tick(
tick_duration,
&mut transform,
dummy_entity,
&mut event_writer,
)
};
// Propagate events
{
let mut events =
world.get_resource_mut::<Events<TweenCompleted>>().unwrap();
events.update();
}
// Check actual values
assert_eq!(tween.direction(), direction);
assert_eq!(actual_state, expected_state);
assert!(abs_diff_eq(tween.progress(), progress, 1e-5));
assert_eq!(tween.times_completed(), times_completed);
assert!(transform
.translation
.abs_diff_eq(expected_translation, 1e-5));
assert!(transform.rotation.abs_diff_eq(Quat::IDENTITY, 1e-5));
let cb_mon = callback_monitor.lock().unwrap();
assert_eq!(cb_mon.invoke_count, times_completed as u64);
assert_eq!(cb_mon.last_reported_count, times_completed);
{
let mut event_reader = event_reader_system_state.get_mut(&mut world);
let event = event_reader.iter().next();
if just_completed {
assert!(event.is_some());
if let Some(event) = event {
assert_eq!(event.entity, dummy_entity);
assert_eq!(event.user_data, USER_DATA);
}
} else {
assert!(event.is_none());
}
}
}
// Rewind
tween.rewind();
assert_eq!(tween.direction(), *tweening_direction); // does not change
assert!(abs_diff_eq(tween.progress(), 0., 1e-5));
assert_eq!(tween.times_completed(), 0);
// Dummy tick to update target
let actual_state = {
let mut event_writer = event_writer_system_state.get_mut(&mut world);
tween.tick(
Duration::ZERO,
&mut transform,
Entity::from_raw(0),
&mut event_writer,
)
};
assert_eq!(actual_state, TweenState::Active);
let expected_translation = if tweening_direction.is_backward() {
Vec3::ONE
} else {
Vec3::ZERO
};
assert!(transform
.translation
.abs_diff_eq(expected_translation, 1e-5));
assert!(transform.rotation.abs_diff_eq(Quat::IDENTITY, 1e-5));
// Clear callback
tween.clear_completed();
assert!(tween.on_completed.is_none());
}
}
}
#[test]
fn tween_dir() {
let mut tween = Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(1.0),
TransformPositionLens {
start: Vec3::ZERO,
end: Vec3::ONE,
},
);
// Default
assert_eq!(tween.direction(), TweeningDirection::Forward);
assert!(abs_diff_eq(tween.progress(), 0.0, 1e-5));
// no-op
tween.set_direction(TweeningDirection::Forward);
assert_eq!(tween.direction(), TweeningDirection::Forward);
assert!(abs_diff_eq(tween.progress(), 0.0, 1e-5));
// Backward
tween.set_direction(TweeningDirection::Backward);
assert_eq!(tween.direction(), TweeningDirection::Backward);
// progress is independent of direction
assert!(abs_diff_eq(tween.progress(), 0.0, 1e-5));
// Progress-invariant
tween.set_direction(TweeningDirection::Forward);
tween.set_progress(0.3);
assert!(abs_diff_eq(tween.progress(), 0.3, 1e-5));
tween.set_direction(TweeningDirection::Backward);
// progress is independent of direction
assert!(abs_diff_eq(tween.progress(), 0.3, 1e-5));
// Dummy world and event writer
let mut world = World::new();
world.insert_resource(Events::<TweenCompleted>::default());
let mut event_writer_system_state: SystemState<EventWriter<TweenCompleted>> =
SystemState::new(&mut world);
// Progress always increases alongside the current direction
let dummy_entity = Entity::from_raw(0);
let mut transform = Transform::default();
let mut event_writer = event_writer_system_state.get_mut(&mut world);
tween.set_direction(TweeningDirection::Backward);
assert!(abs_diff_eq(tween.progress(), 0.3, 1e-5));
tween.tick(
Duration::from_secs_f32(0.1),
&mut transform,
dummy_entity,
&mut event_writer,
);
assert!(abs_diff_eq(tween.progress(), 0.4, 1e-5));
assert!(transform.translation.abs_diff_eq(Vec3::splat(0.6), 1e-5));
}
/// Test ticking a sequence of tweens.
#[test]
fn seq_tick() {
let tween1 = Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(1.0),
TransformPositionLens {
start: Vec3::ZERO,
end: Vec3::ONE,
},
);
let tween2 = Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(1.0),
TransformRotationLens {
start: Quat::IDENTITY,
end: Quat::from_rotation_x(90_f32.to_radians()),
},
);
let mut seq = tween1.then(tween2);
let mut transform = Transform::default();
// Dummy world and event writer
let mut world = World::new();
world.insert_resource(Events::<TweenCompleted>::default());
let mut system_state: SystemState<EventWriter<TweenCompleted>> =
SystemState::new(&mut world);
let mut event_writer = system_state.get_mut(&mut world);
for i in 1..=16 {
let state = seq.tick(
Duration::from_secs_f32(0.2),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
if i < 5 {
assert_eq!(state, TweenState::Active);
let r = i as f32 * 0.2;
assert_eq!(transform, Transform::from_translation(Vec3::splat(r)));
} else if i < 10 {
assert_eq!(state, TweenState::Active);
let alpha_deg = (18 * (i - 5)) as f32;
assert!(transform.translation.abs_diff_eq(Vec3::ONE, 1e-5));
assert!(transform
.rotation
.abs_diff_eq(Quat::from_rotation_x(alpha_deg.to_radians()), 1e-5));
} else {
assert_eq!(state, TweenState::Completed);
assert!(transform.translation.abs_diff_eq(Vec3::ONE, 1e-5));
assert!(transform
.rotation
.abs_diff_eq(Quat::from_rotation_x(90_f32.to_radians()), 1e-5));
}
}
}
/// Test crossing tween boundaries in one tick.
#[test]
fn seq_tick_boundaries() {
let mut seq = Sequence::new((0..3).map(|i| {
Tween::new(
EaseMethod::Linear,
Duration::from_secs(1),
TransformPositionLens {
start: Vec3::splat(i as f32),
end: Vec3::splat((i + 1) as f32),
},
)
.with_repeat_count(RepeatCount::Finite(1))
}));
let mut transform = Transform::default();
// Dummy world and event writer
let mut world = World::new();
world.insert_resource(Events::<TweenCompleted>::default());
let mut system_state: SystemState<EventWriter<TweenCompleted>> =
SystemState::new(&mut world);
let mut event_writer = system_state.get_mut(&mut world);
// Tick halfway through the first tween, then in one tick:
// - Finish the first tween
// - Start and finish the second tween
// - Start the third tween
for delta in [0.5, 2.0] {
seq.tick(
Duration::from_secs_f32(delta),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
}
assert_eq!(seq.index(), 2);
assert!(transform.translation.abs_diff_eq(Vec3::splat(2.5), 1e-5));
}
/// Sequence::new() and various Sequence-specific methods
#[test]
fn seq_iter() {
let mut seq = Sequence::new((1..5).map(|i| {
Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(0.2 * i as f32),
TransformPositionLens {
start: Vec3::ZERO,
end: Vec3::ONE,
},
)
}));
let mut progress = 0.;
for i in 1..5 {
assert_eq!(seq.index(), i - 1);
assert!((seq.progress() - progress).abs() < 1e-5);
let secs = 0.2 * i as f32;
assert_eq!(seq.current().duration(), Duration::from_secs_f32(secs));
progress += 0.25;
seq.set_progress(progress);
assert_eq!(seq.times_completed(), if i == 4 { 1 } else { 0 });
}
seq.rewind();
assert_eq!(seq.progress(), 0.);
assert_eq!(seq.times_completed(), 0);
}
/// Test ticking parallel tracks of tweens.
#[test]
fn tracks_tick() {
let tween1 = Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(1.),
TransformPositionLens {
start: Vec3::ZERO,
end: Vec3::ONE,
},
);
let tween2 = Tween::new(
EaseMethod::Linear,
Duration::from_secs_f32(0.8), // shorter
TransformRotationLens {
start: Quat::IDENTITY,
end: Quat::from_rotation_x(90_f32.to_radians()),
},
);
let mut tracks = Tracks::new([tween1, tween2]);
assert_eq!(tracks.duration(), Duration::from_secs_f32(1.)); // max(1., 0.8)
let mut transform = Transform::default();
// Dummy world and event writer
let mut world = World::new();
world.insert_resource(Events::<TweenCompleted>::default());
let mut system_state: SystemState<EventWriter<TweenCompleted>> =
SystemState::new(&mut world);
let mut event_writer = system_state.get_mut(&mut world);
for i in 1..=6 {
let state = tracks.tick(
Duration::from_secs_f32(0.2),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
if i < 5 {
assert_eq!(state, TweenState::Active);
assert_eq!(tracks.times_completed(), 0);
let r = i as f32 * 0.2;
assert!((tracks.progress() - r).abs() < 1e-5);
let alpha_deg = 22.5 * i as f32;
assert!(transform.translation.abs_diff_eq(Vec3::splat(r), 1e-5));
assert!(transform
.rotation
.abs_diff_eq(Quat::from_rotation_x(alpha_deg.to_radians()), 1e-5));
} else {
assert_eq!(state, TweenState::Completed);
assert_eq!(tracks.times_completed(), 1);
assert!((tracks.progress() - 1.).abs() < 1e-5);
assert!(transform.translation.abs_diff_eq(Vec3::ONE, 1e-5));
assert!(transform
.rotation
.abs_diff_eq(Quat::from_rotation_x(90_f32.to_radians()), 1e-5));
}
}
tracks.rewind();
assert_eq!(tracks.times_completed(), 0);
assert!(tracks.progress().abs() < 1e-5);
tracks.set_progress(0.9);
assert!((tracks.progress() - 0.9).abs() < 1e-5);
// tick to udpate state (set_progress() does not update state)
let state = tracks.tick(
Duration::from_secs_f32(0.),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
assert_eq!(state, TweenState::Active);
assert_eq!(tracks.times_completed(), 0);
tracks.set_progress(3.2);
assert!((tracks.progress() - 1.).abs() < 1e-5);
// tick to udpate state (set_progress() does not update state)
let state = tracks.tick(
Duration::from_secs_f32(0.),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
assert_eq!(state, TweenState::Completed);
assert_eq!(tracks.times_completed(), 1); // no looping
tracks.set_progress(-0.5);
assert!(tracks.progress().abs() < 1e-5);
// tick to udpate state (set_progress() does not update state)
let state = tracks.tick(
Duration::from_secs_f32(0.),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
assert_eq!(state, TweenState::Active);
assert_eq!(tracks.times_completed(), 0); // no looping
}
/// Test ticking a delay.
#[test]
fn delay_tick() {
let duration = Duration::from_secs_f32(1.0);
let mut delay = Delay::new(duration);
{
let tweenable: &dyn Tweenable<Transform> = &delay;
assert_eq!(tweenable.duration(), duration);
assert!(tweenable.progress().abs() < 1e-5);
}
let mut transform = Transform::default();
// Dummy world and event writer
let mut world = World::new();
world.insert_resource(Events::<TweenCompleted>::default());
let mut system_state: SystemState<EventWriter<TweenCompleted>> =
SystemState::new(&mut world);
let mut event_writer = system_state.get_mut(&mut world);
for i in 1..=6 {
let state = delay.tick(
Duration::from_secs_f32(0.2),
&mut transform,
Entity::from_raw(0),
&mut event_writer,
);
{
let tweenable: &dyn Tweenable<Transform> = &delay;
if i < 5 {
assert_eq!(state, TweenState::Active);
let r = i as f32 * 0.2;
assert!((tweenable.progress() - r).abs() < 1e-5);
} else {
assert_eq!(state, TweenState::Completed);
assert!((tweenable.progress() - 1.).abs() < 1e-5);
}
}
}
}
#[test]
#[should_panic]
fn delay_zero_duration_panics() {
let _ = Delay::new(Duration::ZERO);
}
}