Support Warning
WebGPU is currently only supported on Chrome starting with version 113, and only on desktop. If they don't work on your configuration, you can check the WebGL2 examples here.easing_functions.rs:
//! Demonstrates the behavior of the built-in easing functions.
use bevy::{prelude::*, sprite::Anchor};
#[derive(Component)]
struct SelectedEaseFunction(EaseFunction, Color);
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, display_curves)
.run();
}
fn setup(mut commands: Commands) {
commands.spawn(Camera2d);
let text_font = TextFont {
font_size: 10.0,
..default()
};
for (i, functions) in [
EaseFunction::SineIn,
EaseFunction::SineOut,
EaseFunction::SineInOut,
EaseFunction::QuadraticIn,
EaseFunction::QuadraticOut,
EaseFunction::QuadraticInOut,
EaseFunction::CubicIn,
EaseFunction::CubicOut,
EaseFunction::CubicInOut,
EaseFunction::QuarticIn,
EaseFunction::QuarticOut,
EaseFunction::QuarticInOut,
EaseFunction::QuinticIn,
EaseFunction::QuinticOut,
EaseFunction::QuinticInOut,
EaseFunction::CircularIn,
EaseFunction::CircularOut,
EaseFunction::CircularInOut,
EaseFunction::ExponentialIn,
EaseFunction::ExponentialOut,
EaseFunction::ExponentialInOut,
EaseFunction::ElasticIn,
EaseFunction::ElasticOut,
EaseFunction::ElasticInOut,
EaseFunction::BackIn,
EaseFunction::BackOut,
EaseFunction::BackInOut,
EaseFunction::BounceIn,
EaseFunction::BounceOut,
EaseFunction::BounceInOut,
EaseFunction::Linear,
EaseFunction::Steps(4),
EaseFunction::Elastic(50.0),
]
.chunks(3)
.enumerate()
{
for (j, function) in functions.iter().enumerate() {
let color = Hsla::hsl(i as f32 / 11.0 * 360.0, 0.8, 0.75).into();
commands
.spawn((
Text2d(format!("{:?}", function)),
text_font.clone(),
TextColor(color),
Transform::from_xyz(
i as f32 * 113.0 - 1280.0 / 2.0 + 25.0,
-100.0 - ((j as f32 * 250.0) - 300.0),
0.0,
),
Anchor::TopLeft,
SelectedEaseFunction(*function, color),
))
.with_children(|p| {
p.spawn((
Sprite::from_color(color, Vec2::splat(5.0)),
Transform::from_xyz(SIZE_PER_FUNCTION + 5.0, 15.0, 0.0),
));
p.spawn((
Sprite::from_color(color, Vec2::splat(4.0)),
Transform::from_xyz(0.0, 0.0, 0.0),
));
});
}
}
commands.spawn((
Text::default(),
Node {
position_type: PositionType::Absolute,
bottom: Val::Px(12.0),
left: Val::Px(12.0),
..default()
},
));
}
const SIZE_PER_FUNCTION: f32 = 95.0;
fn display_curves(
mut gizmos: Gizmos,
ease_functions: Query<(&SelectedEaseFunction, &Transform, &Children)>,
mut transforms: Query<&mut Transform, Without<SelectedEaseFunction>>,
mut ui_text: Single<&mut Text>,
time: Res<Time>,
) {
let samples = 100;
let duration = 2.5;
let time_margin = 0.5;
let now = ((time.elapsed_secs() % (duration + time_margin * 2.0) - time_margin) / duration)
.clamp(0.0, 1.0);
ui_text.0 = format!("Progress: {:.2}", now);
for (SelectedEaseFunction(function, color), transform, children) in &ease_functions {
// Draw a box around the curve
gizmos.linestrip_2d(
[
Vec2::new(transform.translation.x, transform.translation.y + 15.0),
Vec2::new(
transform.translation.x + SIZE_PER_FUNCTION,
transform.translation.y + 15.0,
),
Vec2::new(
transform.translation.x + SIZE_PER_FUNCTION,
transform.translation.y + 15.0 + SIZE_PER_FUNCTION,
),
Vec2::new(
transform.translation.x,
transform.translation.y + 15.0 + SIZE_PER_FUNCTION,
),
Vec2::new(transform.translation.x, transform.translation.y + 15.0),
],
color.darker(0.4),
);
// Draw the curve
let f = EasingCurve::new(0.0, 1.0, *function);
let drawn_curve = f.by_ref().graph().map(|(x, y)| {
Vec2::new(
x * SIZE_PER_FUNCTION + transform.translation.x,
y * SIZE_PER_FUNCTION + transform.translation.y + 15.0,
)
});
gizmos.curve_2d(
&drawn_curve,
drawn_curve.domain().spaced_points(samples).unwrap(),
*color,
);
// Show progress along the curve for the current time
let y = f.sample(now).unwrap() * SIZE_PER_FUNCTION + 15.0;
transforms.get_mut(children[0]).unwrap().translation.y = y;
transforms.get_mut(children[1]).unwrap().translation =
Vec3::new(now * SIZE_PER_FUNCTION, y, 0.0);
gizmos.linestrip_2d(
[
Vec2::new(transform.translation.x, transform.translation.y + y),
Vec2::new(
transform.translation.x + SIZE_PER_FUNCTION,
transform.translation.y + y,
),
],
color.darker(0.2),
);
}
}