Easings on Bevy components using interpolation.
Add the plugin to your app:
use bevy::prelude::*;
use bevy_easings::EasingsPlugin;
fn main() {
App::new()
.add_plugin(EasingsPlugin);
}And then just ease your components to their new state!
use bevy::prelude::*;
use bevy_easings::*;
fn my_system(mut commands: Commands){
commands
.spawn((
SpriteBundle {
..Default::default()
},
Sprite {
custom_size: Some(Vec2::new(10., 10.)),
..Default::default()
}
.ease_to(
Sprite {
custom_size: Some(Vec2::new(100., 100.)),
..Default::default()
},
EaseFunction::QuadraticIn,
EasingType::PingPong {
duration: std::time::Duration::from_secs(1),
pause: Some(std::time::Duration::from_millis(500)),
},
),
));
}If the component being eased is not already a component of the entity, the component should first be inserted for the target entity.
You can chain easings, if they are not set to repeat they will happen in sequence.
use bevy::prelude::*;
use bevy_easings::*;
fn my_system(mut commands: Commands){
commands
.spawn((
SpriteBundle {
..Default::default()
},
Sprite {
custom_size: Some(Vec2::new(10., 10.)),
..Default::default()
}
.ease_to(
Sprite {
custom_size: Some(Vec2::new(300., 300.)),
..Default::default()
},
EaseFunction::QuadraticIn,
EasingType::Once {
duration: std::time::Duration::from_secs(1),
},
)
.ease_to(
Sprite {
custom_size: Some(Vec2::new(350., 350.)),
..Default::default()
},
EaseFunction::QuadraticIn,
EasingType::PingPong {
duration: std::time::Duration::from_millis(500),
pause: Some(std::time::Duration::from_millis(200)),
},
),
));
}To be able to ease a component, it needs to implement the traits Default and Lerp. This trait is re-exported by beavy_easings.
use bevy::prelude::*;
use bevy_easings::*;
#[derive(Default, Component)]
struct CustomComponent(f32);
impl Lerp for CustomComponent {
type Scalar = f32;
fn lerp(&self, other: &Self, scalar: &Self::Scalar) -> Self {
CustomComponent(interpolation::lerp(&self.0, &other.0, scalar))
}
}The basic formula for lerp (linear interpolation) is self + (other - self) * scalar.
Then, the system custom_ease_system::<CustomComponent> needs to be added to the application.
See examples
Many ease functions are available:
- QuadraticIn
- QuadraticOut
- QuadraticInOut
- CubicIn
- CubicOut
- CubicInOut
- QuarticIn
- QuarticOut
- QuarticInOut
- QuinticIn
- QuinticOut
- QuinticInOut
- SineIn
- SineOut
- SineInOut
- CircularIn
- CircularOut
- CircularInOut
- ExponentialIn
- ExponentialOut
- ExponentialInOut
- ElasticIn
- ElasticOut
- ElasticInOut
- BackIn
- BackOut
- BackInOut
- BounceIn
- BounceOut
- BounceInOut
| Bevy | bevy_easings |
|---|---|
| main | main |
| 0.9 | 0.9 |
| 0.8 | 0.8 |
| 0.7 | 0.7 |
| 0.6 | 0.6 |
| 0.5 | 0.4 |