This example is running in WebGL2 and should work in most browsers. You can check the WebGPU examples here.
//! 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),
);
}
}