WebXR error in WebGPURenderer / WebGLBackend in non layer devices

[danrossi]

Description

I just pulled changes into a merged fork for a PR I made. And found errors in WebXR so it's stopping working altogether. I am not sure what it is. I checked against a fresh checkout.

It's suggesting this is null

renderTargetContextData.framebuffers

three.js/src/renderers/webgl-fallback/WebGLBackend.js

Line 600 in c0088a7

const fb = renderTargetContextData.framebuffers[ renderContext.getCacheKey() ];

Related to #31134

Reproduction steps

1. visit https://electroteque.org/dev/three/examples/webgpu_xr_cubes.html
2. Launch WebXR
3. Errors display in the animation frame.

Code

// code goes here

Live example

• WebGPU XR Cubes

Screenshots

Version

176

Device

Desktop

Browser

Chrome

OS

Windows

[mrdoob]

@cabanier @Mugen87 Any ideas?

[cabanier]

@cabanier @Mugen87 Any ideas?

I'll take a look. It seems that this user is using the WebXR polyfill.

[danrossi]

It's the emulator. I can bring it up in the Quest. But is also a problem on the Rift via chrome.

[danrossi]

I updated the title. It's ok in Quest 2 somehow. Just in Chrome / Rift non layer WebXR and the immersive emulator extension.

[cabanier]

I updated the title. It's ok in Quest 2 somehow. Just in Chrome / Rift non layer WebXR and the immersive emulator extension.

I see that it renders incorrectly if I turn layers off. I usually test with that before submitting but must have missed it

[danrossi]

It's all good easily missed. There is so much stuff in there to test case now. I wonder if there is a way to headless test WebXR for layers / non layers ? Is that already happening ?

[cabanier]

@cabanier @Mugen87 Any ideas?

#31198 will address this along with some other side issues.

[danrossi]

I hope I can still update this ticket. I updated and now I get framebuffer errors with no XR display. In both Rift in Chrome and the emulator extension. So non layer XR. In the rift it's in the home screen so won't launch XR.

https://electroteque.org/dev/three/examples/webgpu_xr_cubes.html

[cabanier]

It's just a warning from chromium. I'll silence it.

[danrossi]

never mind. I'm sorry confirming it's ok on Rift. I had the extension enabled. warnings can be ignored. Will close.

[Mugen87]

@cabanier Should we still keep #31201 and merge the proposed changes?

[cabanier]

Yes. The warning was valid

…

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