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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.
Support for WebGPU in Bevy hasn't been released yet, this example has been compiled using the main branch.

//! Illustrates how to scale an object in each direction.

use std::f32::consts::PI;

use bevy::math::Vec3Swizzles;
use bevy::prelude::*;

// Define a component to keep information for the scaled object.
struct Scaling {
    scale_direction: Vec3,
    scale_speed: f32,
    max_element_size: f32,
    min_element_size: f32,

// Implement a simple initialization.
impl Scaling {
    fn new() -> Self {
        Scaling {
            scale_direction: Vec3::X,
            scale_speed: 2.0,
            max_element_size: 5.0,
            min_element_size: 1.0,

fn main() {
        .add_systems(Startup, setup)
        .add_systems(Update, (change_scale_direction, scale_cube))

// Startup system to setup the scene and spawn all relevant entities.
fn setup(
    mut commands: Commands,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
) {
    // Spawn a cube to scale.
        PbrBundle {
            mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
            material: materials.add(Color::WHITE.into()),
            transform: Transform::from_rotation(Quat::from_rotation_y(PI / 4.0)),

    // Spawn a camera looking at the entities to show what's happening in this example.
    commands.spawn(Camera3dBundle {
        transform: Transform::from_xyz(0.0, 10.0, 20.0).looking_at(Vec3::ZERO, Vec3::Y),

    // Add a light source for better 3d visibility.
    commands.spawn(PointLightBundle {
        transform: Transform::from_translation(Vec3::ONE * 3.0),

// This system will check if a scaled entity went above or below the entities scaling bounds
// and change the direction of the scaling vector.
fn change_scale_direction(mut cubes: Query<(&mut Transform, &mut Scaling)>) {
    for (mut transform, mut cube) in &mut cubes {
        // If an entity scaled beyond the maximum of its size in any dimension
        // the scaling vector is flipped so the scaling is gradually reverted.
        // Additionally, to ensure the condition does not trigger again we floor the elements to
        // their next full value, which should be max_element_size at max.
        if transform.scale.max_element() > cube.max_element_size {
            cube.scale_direction *= -1.0;
            transform.scale = transform.scale.floor();
        // If an entity scaled beyond the minimum of its size in any dimension
        // the scaling vector is also flipped.
        // Additionally the Values are ceiled to be min_element_size at least
        // and the scale direction is flipped.
        // This way the entity will change the dimension in which it is scaled any time it
        // reaches its min_element_size.
        if transform.scale.min_element() < cube.min_element_size {
            cube.scale_direction *= -1.0;
            transform.scale = transform.scale.ceil();
            cube.scale_direction = cube.scale_direction.zxy();

// This system will scale any entity with assigned Scaling in each direction
// by cycling through the directions to scale.
fn scale_cube(mut cubes: Query<(&mut Transform, &Scaling)>, timer: Res<Time>) {
    for (mut transform, cube) in &mut cubes {
        transform.scale += cube.scale_direction * cube.scale_speed * timer.delta_seconds();