[Feature]: Support for WebGPU on Xbox

[AshleyScirra]

Describe the feature/enhancement you need

Ref discussion: #4138

WebView2 on Xbox One does not appear to support WebGPU, even though WebView2 on Windows does. Support for WebGPU is potentially important for web games as it allows for better performance and rendering features.

For a minimal repro, just point a WebView2 at this URL: https://webgpu.github.io/webgpu-samples/samples/helloTriangle

It works in WebView2 on Windows, but on Xbox One it reports TypeError: Cannot read properties of null (reading 'requestDevice'). Note it does not say that navigator.gpu is undefined, so this appears to indicate the WebGPU API is implemented, but no adapters/devices are available.

AFAIK Xbox One supports DirectX 12, so in theory WebGPU support is possible as it's designed to work on top of DX12, but perhaps there are some Xbox-specific details that need to be implemented.

The scenario/use case where you would use this feature

High-performance web games in WebView2.

How important is this request to you?

Nice to have. There are other ways to tackle this, but having official API support would be beneficial.

Suggested implementation

Hopefully this is only a matter of providing access to the GPU device on Xbox. AFAIK Xbox supports DirectX 12 which is one of the backends WebGPU was specifically designed for, and it works on Windows already, so in theory all the technology is there.

What does your app do? Is there a pending deadline for this request?

We're looking to add support for publishing high-performance web games on Xbox from our game development tool Construct.

AB#47690642

[AshleyScirra]

I was just looking at Platform and API support for Dawn/Tint and it currently notes:

Microsoft's D3D12
...
Xbox: Not supported, contributions welcome.

So I suppose this is something the Dawn WebGPU implementation does not yet implement. It'd be great to see support though.