1802983 - Firefox WebIDL `GPURenderPassColorAttachment` needs to be updated

Status: RESOLVED DUPLICATE of bug 1817541

(Core :: Graphics: WebGPU, enhancement, P3)

Description

[Jim Blandy :jimb]

Among the various changes to the WebGPU WebIDL interface, the GPURenderPassColorAttachment has been changed, and needs to be brought forward. wgpu itself supports the modern interface, so we have an old content API driven by a new implementation: all that's needed is to update the bindings.

There are plenty of other WebIDL changes we need to catch up with, but this one does make it impossible to run wgpu examples in wasm using Firefox's WebGPU implementation as the back end. Since I've done some of the research I wanted to at least write it down.

In the WebGPU specification, GPURenderPassColorAttachment now has separate clearValue and loadOp members, whereas Firefox's old WebGPU.webidl has only a single loadValue member.

In Firefox, mozilla::webgpu::BeginRenderPass takes care of converting the old mozilla::dom::binding_detail::GPURenderPassColorAttachment struct to the new wgpu_core::command::render::RenderPassColorAttachment. This could mostly go away once we update Firefox's WebIDL, although there are some minor differences between wgpu_core's type and the new WebIDL.