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```
``````//! Demonstrates how to work with Cubic curves.

use bevy::{
color::palettes::css::{ORANGE, SILVER, WHITE},
math::vec3,
prelude::*,
};

#[derive(Component)]
struct Curve(CubicCurve<Vec3>);

fn main() {
App::new()
.run();
}

fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
// These points will define the curve
// https://en.wikipedia.org/wiki/B%C3%A9zier_curve
let points = [[
vec3(-6., 2., 0.),
vec3(12., 8., 0.),
vec3(-12., 8., 0.),
vec3(6., 2., 0.),
]];

// Make a CubicCurve
let bezier = CubicBezier::new(points).to_curve();

// Spawning a cube to experiment on
commands.spawn((
PbrBundle {
transform: Transform::from_translation(points[0][0]),
..default()
},
Curve(bezier),
));

// Some light to see something
commands.spawn(PointLightBundle {
point_light: PointLight {
intensity: 10_000_000.,
range: 100.0,
..default()
},
transform: Transform::from_xyz(8., 16., 8.),
..default()
});

// ground plane
commands.spawn(PbrBundle {
..default()
});

// The camera
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(0., 6., 12.).looking_at(Vec3::new(0., 3., 0.), Vec3::Y),
..default()
});
}

fn animate_cube(time: Res<Time>, mut query: Query<(&mut Transform, &Curve)>, mut gizmos: Gizmos) {
let t = (time.elapsed_seconds().sin() + 1.) / 2.;

for (mut transform, cubic_curve) in &mut query {
// Draw the curve
gizmos.linestrip(cubic_curve.0.iter_positions(50), WHITE);
// position takes a point from the curve where 0 is the initial point
// and 1 is the last point
transform.translation = cubic_curve.0.position(t);
}
}
``````