//! Demonstrates using a custom extension to the `StandardMaterial` to modify the results of the builtin pbr shader. use bevy::{ color::palettes::basic::RED, pbr::{ExtendedMaterial, MaterialExtension, OpaqueRendererMethod}, prelude::*, render::render_resource::*, }; /// This example uses a shader source file from the assets subdirectory const SHADER_ASSET_PATH: &str = "shaders/extended_material.wgsl"; fn main() { App::new() .add_plugins(DefaultPlugins) .add_plugins(MaterialPlugin::< ExtendedMaterial<StandardMaterial, MyExtension>, >::default()) .add_systems(Startup, setup) .add_systems(Update, rotate_things) .run(); } fn setup( mut commands: Commands, mut meshes: ResMut<Assets<Mesh>>, mut materials: ResMut<Assets<ExtendedMaterial<StandardMaterial, MyExtension>>>, ) { // sphere commands.spawn(( Mesh3d(meshes.add(Sphere::new(1.0))), MeshMaterial3d(materials.add(ExtendedMaterial { base: StandardMaterial { base_color: RED.into(), // can be used in forward or deferred mode opaque_render_method: OpaqueRendererMethod::Auto, // in deferred mode, only the PbrInput can be modified (uvs, color and other material properties), // in forward mode, the output can also be modified after lighting is applied. // see the fragment shader `extended_material.wgsl` for more info. // Note: to run in deferred mode, you must also add a `DeferredPrepass` component to the camera and either // change the above to `OpaqueRendererMethod::Deferred` or add the `DefaultOpaqueRendererMethod` resource. ..Default::default() }, extension: MyExtension { quantize_steps: 3 }, })), Transform::from_xyz(0.0, 0.5, 0.0), )); // light commands.spawn(( DirectionalLight::default(), Transform::from_xyz(1.0, 1.0, 1.0).looking_at(Vec3::ZERO, Vec3::Y), Rotate, )); // camera commands.spawn(( Camera3d::default(), Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y), )); } #[derive(Component)] struct Rotate; fn rotate_things(mut q: Query<&mut Transform, With<Rotate>>, time: Res<Time>) { for mut t in &mut q { t.rotate_y(time.delta_secs()); } } #[derive(Asset, AsBindGroup, Reflect, Debug, Clone)] struct MyExtension { // We need to ensure that the bindings of the base material and the extension do not conflict, // so we start from binding slot 100, leaving slots 0-99 for the base material. #[uniform(100)] quantize_steps: u32, } impl MaterialExtension for MyExtension { fn fragment_shader() -> ShaderRef { SHADER_ASSET_PATH.into() } fn deferred_fragment_shader() -> ShaderRef { SHADER_ASSET_PATH.into() } }