e6405bb7b4
# Objective
- Reduce the number of rebindings to enable batching of draw commands
## Solution
- Use the new `GpuArrayBuffer` for `MeshUniform` data to store all
`MeshUniform` data in arrays within fewer bindings
- Sort opaque/alpha mask prepass, opaque/alpha mask main, and shadow
phases also by the batch per-object data binding dynamic offset to
improve performance on WebGL2.
---
## Changelog
- Changed: Per-object `MeshUniform` data is now managed by
`GpuArrayBuffer` as arrays in buffers that need to be indexed into.
## Migration Guide
Accessing the `model` member of an individual mesh object's shader
`Mesh` struct the old way where each `MeshUniform` was stored at its own
dynamic offset:
```rust
struct Vertex {
@location(0) position: vec3<f32>,
};
fn vertex(vertex: Vertex) -> VertexOutput {
var out: VertexOutput;
out.clip_position = mesh_position_local_to_clip(
mesh.model,
vec4<f32>(vertex.position, 1.0)
);
return out;
}
```
The new way where one needs to index into the array of `Mesh`es for the
batch:
```rust
struct Vertex {
@builtin(instance_index) instance_index: u32,
@location(0) position: vec3<f32>,
};
fn vertex(vertex: Vertex) -> VertexOutput {
var out: VertexOutput;
out.clip_position = mesh_position_local_to_clip(
mesh[vertex.instance_index].model,
vec4<f32>(vertex.position, 1.0)
);
return out;
}
```
Note that using the instance_index is the default way to pass the
per-object index into the shader, but if you wish to do custom rendering
approaches you can pass it in however you like.
---------
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com>
19 lines
458 B
WebGPU Shading Language
19 lines
458 B
WebGPU Shading Language
#define_import_path bevy_pbr::prepass_bindings
|
|
#import bevy_render::view View
|
|
#import bevy_render::globals Globals
|
|
#import bevy_pbr::mesh_types
|
|
|
|
@group(0) @binding(0)
|
|
var<uniform> view: View;
|
|
@group(0) @binding(1)
|
|
var<uniform> globals: Globals;
|
|
|
|
#ifdef MOTION_VECTOR_PREPASS
|
|
@group(0) @binding(2)
|
|
var<uniform> previous_view_proj: mat4x4<f32>;
|
|
#endif // MOTION_VECTOR_PREPASS
|
|
|
|
// Material bindings will be in @group(1)
|
|
|
|
#import bevy_pbr::mesh_bindings mesh
|