This example is running in WebGL2 and should work in most browsers. You can check the WebGPU examples here.
//! Test rendering of many cameras and lights
use std::f32::consts::PI;
use bevy::{
math::ops::{cos, sin},
prelude::*,
render::camera::Viewport,
};
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, setup)
.add_systems(Update, rotate_cameras)
.run();
}
const CAMERA_ROWS: usize = 4;
const CAMERA_COLS: usize = 4;
const NUM_LIGHTS: usize = 5;
/// set up a simple 3D scene
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
window: Query<&Window>,
) {
// circular base
commands.spawn((
Mesh3d(meshes.add(Circle::new(4.0))),
MeshMaterial3d(materials.add(Color::WHITE)),
Transform::from_rotation(Quat::from_rotation_x(-std::f32::consts::FRAC_PI_2)),
));
// cube
commands.spawn((
Mesh3d(meshes.add(Cuboid::new(1.0, 1.0, 1.0))),
MeshMaterial3d(materials.add(Color::WHITE)),
Transform::from_xyz(0.0, 0.5, 0.0),
));
// lights
for i in 0..NUM_LIGHTS {
let angle = (i as f32) / (NUM_LIGHTS as f32) * PI * 2.0;
commands.spawn((
PointLight {
color: Color::hsv(angle.to_degrees(), 1.0, 1.0),
intensity: 2_000_000.0 / NUM_LIGHTS as f32,
shadows_enabled: true,
..default()
},
Transform::from_xyz(sin(angle) * 4.0, 2.0, cos(angle) * 4.0),
));
}
// cameras
let window = window.single();
let width = window.resolution.width() / CAMERA_COLS as f32 * window.resolution.scale_factor();
let height = window.resolution.height() / CAMERA_ROWS as f32 * window.resolution.scale_factor();
let mut i = 0;
for y in 0..CAMERA_COLS {
for x in 0..CAMERA_ROWS {
let angle = i as f32 / (CAMERA_ROWS * CAMERA_COLS) as f32 * PI * 2.0;
commands.spawn((
Camera3d::default(),
Camera {
viewport: Some(Viewport {
physical_position: UVec2::new(
(x as f32 * width) as u32,
(y as f32 * height) as u32,
),
physical_size: UVec2::new(width as u32, height as u32),
..default()
}),
order: i,
..default()
},
Transform::from_xyz(sin(angle) * 4.0, 2.5, cos(angle) * 4.0)
.looking_at(Vec3::ZERO, Vec3::Y),
));
i += 1;
}
}
}
fn rotate_cameras(time: Res<Time>, mut query: Query<&mut Transform, With<Camera>>) {
for mut transform in query.iter_mut() {
transform.rotate_around(Vec3::ZERO, Quat::from_rotation_y(time.delta_secs()));
}
}