bevy/examples/2d/custom_gltf_vertex_attribute.rs
Clar Fon efda7f3f9c
Simpler lint fixes: makes ci lints work but disables a lint for now (#15376)
Takes the first two commits from #15375 and adds suggestions from this
comment:
https://github.com/bevyengine/bevy/pull/15375#issuecomment-2366968300

See #15375 for more reasoning/motivation.

## Rebasing (rerunning)

```rust
git switch simpler-lint-fixes
git reset --hard main
cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate
cargo fmt --all
git add --update
git commit --message "rustfmt"
cargo clippy --workspace --all-targets --all-features --fix
cargo fmt --all -- --unstable-features --config normalize_comments=true,imports_granularity=Crate
cargo fmt --all
git add --update
git commit --message "clippy"
git cherry-pick e6c0b94f6795222310fb812fa5c4512661fc7887
```
2024-09-24 11:42:59 +00:00

94 lines
3.1 KiB
Rust

//! Renders a glTF mesh in 2D with a custom vertex attribute.
use bevy::{
gltf::GltfPlugin,
prelude::*,
reflect::TypePath,
render::{
mesh::{MeshVertexAttribute, MeshVertexBufferLayoutRef},
render_resource::*,
},
sprite::{Material2d, Material2dKey, Material2dPlugin, MaterialMesh2dBundle, Mesh2dHandle},
};
/// This example uses a shader source file from the assets subdirectory
const SHADER_ASSET_PATH: &str = "shaders/custom_gltf_2d.wgsl";
/// This vertex attribute supplies barycentric coordinates for each triangle.
///
/// Each component of the vector corresponds to one corner of a triangle. It's
/// equal to 1.0 in that corner and 0.0 in the other two. Hence, its value in
/// the fragment shader indicates proximity to a corner or the opposite edge.
const ATTRIBUTE_BARYCENTRIC: MeshVertexAttribute =
MeshVertexAttribute::new("Barycentric", 2137464976, VertexFormat::Float32x3);
fn main() {
App::new()
.insert_resource(AmbientLight {
color: Color::WHITE,
brightness: 1.0 / 5.0f32,
})
.add_plugins((
DefaultPlugins.set(
GltfPlugin::default()
// Map a custom glTF attribute name to a `MeshVertexAttribute`.
.add_custom_vertex_attribute("_BARYCENTRIC", ATTRIBUTE_BARYCENTRIC),
),
Material2dPlugin::<CustomMaterial>::default(),
))
.add_systems(Startup, setup)
.run();
}
fn setup(
mut commands: Commands,
asset_server: Res<AssetServer>,
mut materials: ResMut<Assets<CustomMaterial>>,
) {
// Add a mesh loaded from a glTF file. This mesh has data for `ATTRIBUTE_BARYCENTRIC`.
let mesh = asset_server.load(
GltfAssetLabel::Primitive {
mesh: 0,
primitive: 0,
}
.from_asset("models/barycentric/barycentric.gltf"),
);
commands.spawn(MaterialMesh2dBundle {
mesh: Mesh2dHandle(mesh),
material: materials.add(CustomMaterial {}),
transform: Transform::from_scale(150.0 * Vec3::ONE),
..default()
});
// Add a camera
commands.spawn(Camera2dBundle { ..default() });
}
/// This custom material uses barycentric coordinates from
/// `ATTRIBUTE_BARYCENTRIC` to shade a white border around each triangle. The
/// thickness of the border is animated using the global time shader uniform.
#[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
struct CustomMaterial {}
impl Material2d for CustomMaterial {
fn vertex_shader() -> ShaderRef {
SHADER_ASSET_PATH.into()
}
fn fragment_shader() -> ShaderRef {
SHADER_ASSET_PATH.into()
}
fn specialize(
descriptor: &mut RenderPipelineDescriptor,
layout: &MeshVertexBufferLayoutRef,
_key: Material2dKey<Self>,
) -> Result<(), SpecializedMeshPipelineError> {
let vertex_layout = layout.0.get_layout(&[
Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
Mesh::ATTRIBUTE_COLOR.at_shader_location(1),
ATTRIBUTE_BARYCENTRIC.at_shader_location(2),
])?;
descriptor.vertex.buffers = vec![vertex_layout];
Ok(())
}
}