single projection layer and stencil:true incompatible with multiview patch

[vincentfretin]

Description

The change to WebXRManager from r172

const useLayers = session.enabledFeatures !== undefined && session.enabledFeatures.includes( 'layers' );

to r173

// Check that the browser implements the necessary APIs to use an
// XRProjectionLayer rather than an XRWebGLLayer
const useLayers = typeof XRWebGLBinding !== 'undefined' && 'createProjectionLayer' in XRWebGLBinding.prototype;

now uses a single projection layer instead of XRWebGLLayer on my Quest 3 r72 browser 36.5
so this is triggering the branch where we have the multiview patch now
and with <a-scene renderer="stencil:true"> needed for the mirror component, it break my experience completely, all my models are translucent.
If I revert the multiview patch 5b5b032 and fd6e7d8
the single projection layer plus stencil:true work correctly.

I tried to use aframe layer component last time with r172 and stencil:true, it also break in the same way so I gave up on testing layers last time. Now I know the issue was the multiview patch.
I'm currently using a super-three r173 version without the multiview patch.
cc @felixtrz

Reproduction steps

1. set renderer="stencil:true"

Code

// code goes here

Live example

Screenshots

No response

Version

r173

Device

Headset

Browser

No response

OS

No response

[mrxz]

Something seems clearly wrong with the multiview changeset. Enabling it through the renderer has no effect as the flag isn't properly forwarded to the WebXRManager. Should be relatively easy to fix, but ideally having multiview stereo disabled should have no impact, whereas it currently does.

[mrxz]

@vincentfretin Created a PR that should fix the issues: #22.

[vincentfretin]

Yes I did a build with all 4 commits (the previous 2 and 2 of your PR), that fixes the issue with stencil:true.

[vincentfretin]

I also tested
stencil:true;multiviewStereo:true
and
stencil:false;multiviewStereo:true
I don't have the translucent issue, but other issues like canvas textures missing or some materials appearing black, but I guess that's expected from the info in https://aframe.io/docs/1.6.0/components/renderer.html#multiviewstereo

[mrxz]

I don't have the translucent issue, but other issues like canvas textures missing or some materials appearing black, but I guess that's expected from the info in https://aframe.io/docs/1.6.0/components/renderer.html#multiviewstereo

Probably, any texture upload would interfere, which is likely what happens with the canvas textures. There is some mechanism to defer these uploads, though not sure why it isn't working for canvas textures. I do recall video texture uploads having the same problem, so there are still some big caveats to the current implementation. It could be improved, though it also doesn't appear to be used much.

[vincentfretin]

fixed in #22 super-three 0.173.2