
# Objective - Fixes #13872 (also mentioned in #17167) ## Solution - Added conditional padding fields to the shader uniform ## Alternatives ### 1- Use a UVec4 Replace the `u32` field in `MyExtension` by a `UVec4` and only use the `x` coordinate. (This was the original approach, but for consistency with the rest of the codebase, separate padding fields seem to be preferred) ### 2- Don't fix it, unlist it While the fix is quite simple, it does muddy the waters a tiny bit due to `quantize_steps` now being a UVec4 instead of a simple u32. We could simply remove this example from the examples that support WebGL2. ## Testing - Ran the example locally on WebGL2 (and native Vulkan) successfully
107 lines
3.3 KiB
Rust
107 lines
3.3 KiB
Rust
//! 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::new(1),
|
|
})),
|
|
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, Default)]
|
|
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,
|
|
// Web examples WebGL2 support: structs must be 16 byte aligned.
|
|
#[cfg(feature = "webgl2")]
|
|
#[uniform(100)]
|
|
_webgl2_padding_8b: u32,
|
|
#[cfg(feature = "webgl2")]
|
|
#[uniform(100)]
|
|
_webgl2_padding_12b: u32,
|
|
#[cfg(feature = "webgl2")]
|
|
#[uniform(100)]
|
|
_webgl2_padding_16b: u32,
|
|
}
|
|
impl MyExtension {
|
|
fn new(quantize_steps: u32) -> Self {
|
|
Self {
|
|
quantize_steps,
|
|
..default()
|
|
}
|
|
}
|
|
}
|
|
|
|
impl MaterialExtension for MyExtension {
|
|
fn fragment_shader() -> ShaderRef {
|
|
SHADER_ASSET_PATH.into()
|
|
}
|
|
|
|
fn deferred_fragment_shader() -> ShaderRef {
|
|
SHADER_ASSET_PATH.into()
|
|
}
|
|
}
|