webgpu-impl-multipass
Installation
SKILL.md
WebGPU Multi-Pass Rendering
Chain several render passes so earlier passes write intermediate render textures that later passes sample. Covers post-processing chains, deferred shading, shadow mapping, and ping-pong buffers on WebGPU 1.0-stable (Chrome 113+, Safari 26+, Firefox 141+).
Quick Reference
| Pass pattern | Earlier pass writes | Later pass reads | Key requirement |
|---|---|---|---|
| Post-process chain | Offscreen color texture | Full-screen quad samples it | Intermediate texture needs RENDER_ATTACHMENT | TEXTURE_BINDING |
| Ping-pong | Texture A (pass N) | Texture B (pass N+1) | Two textures, swap roles each pass |
| Deferred shading | G-buffer via MRT (multiple color attachments) | Lighting pass samples every G-buffer texture | Each G-buffer texture needs RENDER_ATTACHMENT | TEXTURE_BINDING |
| Shadow map | Depth-only texture from light view | Main pass samples with comparison sampler | Shadow pass uses depthStencilAttachment, no color attachments |
Intermediate render texture usage: ALWAYS
GPUTextureUsage.RENDER_ATTACHMENT | GPUTextureUsage.TEXTURE_BINDING.
Without TEXTURE_BINDING the texture cannot be sampled in a later pass.