mirror of
https://github.com/bevyengine/bevy
synced 2024-11-26 06:30:19 +00:00
f9cc91d5a1
Although we cached hashes of `MeshVertexBufferLayout`, we were paying the cost of `PartialEq` on `InnerMeshVertexBufferLayout` for every entity, every frame. This patch changes that logic to place `MeshVertexBufferLayout`s in `Arc`s so that they can be compared and hashed by pointer. This results in a 28% speedup in the `queue_material_meshes` phase of `many_cubes`, with frustum culling disabled. Additionally, this patch contains two minor changes: 1. This commit flattens the specialized mesh pipeline cache to one level of hash tables instead of two. This saves a hash lookup. 2. The example `many_cubes` has been given a `--no-frustum-culling` flag, to aid in benchmarking. See the Tracy profile: <img width="1064" alt="Screenshot 2024-02-29 144406" src="https://github.com/bevyengine/bevy/assets/157897/18632f1d-1fdd-4ac7-90ed-2d10306b2a1e"> ## Migration guide * Duplicate `MeshVertexBufferLayout`s are now combined into a single object, `MeshVertexBufferLayoutRef`, which contains an atomically-reference-counted pointer to the layout. Code that was using `MeshVertexBufferLayout` may need to be updated to use `MeshVertexBufferLayoutRef` instead.
87 lines
2.7 KiB
Rust
87 lines
2.7 KiB
Rust
//! A shader that reads a mesh's custom vertex attribute.
|
|
|
|
use bevy::{
|
|
pbr::{MaterialPipeline, MaterialPipelineKey},
|
|
prelude::*,
|
|
reflect::TypePath,
|
|
render::{
|
|
mesh::{MeshVertexAttribute, MeshVertexBufferLayoutRef},
|
|
render_resource::{
|
|
AsBindGroup, RenderPipelineDescriptor, ShaderRef, SpecializedMeshPipelineError,
|
|
VertexFormat,
|
|
},
|
|
},
|
|
};
|
|
|
|
fn main() {
|
|
App::new()
|
|
.add_plugins((DefaultPlugins, MaterialPlugin::<CustomMaterial>::default()))
|
|
.add_systems(Startup, setup)
|
|
.run();
|
|
}
|
|
|
|
// A "high" random id should be used for custom attributes to ensure consistent sorting and avoid collisions with other attributes.
|
|
// See the MeshVertexAttribute docs for more info.
|
|
const ATTRIBUTE_BLEND_COLOR: MeshVertexAttribute =
|
|
MeshVertexAttribute::new("BlendColor", 988540917, VertexFormat::Float32x4);
|
|
|
|
/// set up a simple 3D scene
|
|
fn setup(
|
|
mut commands: Commands,
|
|
mut meshes: ResMut<Assets<Mesh>>,
|
|
mut materials: ResMut<Assets<CustomMaterial>>,
|
|
) {
|
|
let mesh = Mesh::from(Cuboid::default())
|
|
// Sets the custom attribute
|
|
.with_inserted_attribute(
|
|
ATTRIBUTE_BLEND_COLOR,
|
|
// The cube mesh has 24 vertices (6 faces, 4 vertices per face), so we insert one BlendColor for each
|
|
vec![[1.0, 0.0, 0.0, 1.0]; 24],
|
|
);
|
|
|
|
// cube
|
|
commands.spawn(MaterialMeshBundle {
|
|
mesh: meshes.add(mesh),
|
|
transform: Transform::from_xyz(0.0, 0.5, 0.0),
|
|
material: materials.add(CustomMaterial {
|
|
color: LinearRgba::WHITE,
|
|
}),
|
|
..default()
|
|
});
|
|
|
|
// camera
|
|
commands.spawn(Camera3dBundle {
|
|
transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
|
|
..default()
|
|
});
|
|
}
|
|
|
|
// This is the struct that will be passed to your shader
|
|
#[derive(Asset, TypePath, AsBindGroup, Debug, Clone)]
|
|
struct CustomMaterial {
|
|
#[uniform(0)]
|
|
color: LinearRgba,
|
|
}
|
|
|
|
impl Material for CustomMaterial {
|
|
fn vertex_shader() -> ShaderRef {
|
|
"shaders/custom_vertex_attribute.wgsl".into()
|
|
}
|
|
fn fragment_shader() -> ShaderRef {
|
|
"shaders/custom_vertex_attribute.wgsl".into()
|
|
}
|
|
|
|
fn specialize(
|
|
_pipeline: &MaterialPipeline<Self>,
|
|
descriptor: &mut RenderPipelineDescriptor,
|
|
layout: &MeshVertexBufferLayoutRef,
|
|
_key: MaterialPipelineKey<Self>,
|
|
) -> Result<(), SpecializedMeshPipelineError> {
|
|
let vertex_layout = layout.0.get_layout(&[
|
|
Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
|
|
ATTRIBUTE_BLEND_COLOR.at_shader_location(1),
|
|
])?;
|
|
descriptor.vertex.buffers = vec![vertex_layout];
|
|
Ok(())
|
|
}
|
|
}
|