Using WebGPU Compute Textures with Three.js

Based on your goal of using WebGPU compute shaders to directly update textures in Three.js materials, I can provide some guidance on the approach and potential challenges.

Direct Texture Usage Approach

Your approach of using the WebGPU texture directly in a Three.js material without reading it back to JavaScript is indeed the optimal path for performance. This is possible in Three.js, but there are some specific considerations:

1. When working with WebGPU in Three.js, you'll need to use textures that are compatible with both the compute pipeline and the rendering pipeline.

2. For your compute shader to write to a texture that Three.js can use, you'll need to use a GPUStorageTexture with write access in your compute shader, and then ensure that same texture is bound to your Three.js material.

Implementation Considerations

When implementing this approach:

1. You'll need to create a texture that can be used both as a storage texture in your compute shader and as a regular texture in your Three.js material.

2. In Three.js, you can use FramebufferTexture or DataTexture to work with WebGPU textures.

3. The copyFramebufferToTexture method of the WebGLRenderer can be useful for transferring texture data if needed:

JAVASCRIPTCopied
renderer.copyFramebufferToTexture(position, texture, level);

4. For your WGSL compute shader, you'll need to declare the texture with the appropriate storage access:

WGSLCopied
@group(0) @binding(0) var output_texture : texture_storage_2d<rgba8unorm, write>;

@compute @workgroup_size(8, 8)
fn main(@builtin(global_invocation_id) global_id : vec3<u32>) {
    // Calculate texture coordinates
    let coords = vec2<u32>(global_id.xy);
    
    // Write to the texture
    textureStore(output_texture, coords, vec4<f32>(/* your color values */));
}

5. After dispatching your compute shader, you'll need to ensure the texture is properly synchronized before it's used for rendering.

Potential Challenges

1. Texture Format Compatibility: Ensure the texture format you use is compatible with both compute shader storage and rendering.

2. Synchronization: You'll need to handle synchronization between compute and render passes.

3. WebGPU Support: WebGPU is still relatively new, so browser support and Three.js integration might have limitations.

4. Binding Management: Properly managing texture bindings between compute and render pipelines can be complex.

For optimal results, you might want to look at the Three.js examples that specifically use WebGPU compute shaders and adapt those patterns to your specific needs. The approach is definitely feasible, but requires careful management of the WebGPU resources and their integration with Three.js.