bevy/examples/shader/animate_shader.rs

//! A shader that uses dynamic data like the time since startup.
//! The time data is in the globals binding which is part of the `mesh_view_bindings` shader import.

use bevy::{
    prelude::*,
    reflect::TypePath,
    render::render_resource::{AsBindGroup, ShaderRef},
};

fn main() {
    App::new()
        .add_plugins((DefaultPlugins, MaterialPlugin::<CustomMaterial>::default()))
        .add_systems(Startup, setup)
        .run();
}

fn setup(
    mut commands: Commands,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<CustomMaterial>>,
) {
    // cube
    commands.spawn(MaterialMeshBundle {
        mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
        transform: Transform::from_xyz(0.0, 0.5, 0.0),
        material: materials.add(CustomMaterial {}),
        ..default()
    });

    // camera
    commands.spawn(Camera3dBundle {
        transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
        ..default()
    });
}

#[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
struct CustomMaterial {}

impl Material for CustomMaterial {
    fn fragment_shader() -> ShaderRef {
        "shaders/animate_shader.wgsl".into()
    }
}