Extremely slow performance with specific test file

[hybridherbst]

Description

The entire browser locks up when loading the comparatively small attached file.
This seems to be a threejs issue as it also happens in threejs editor and not only in model-viewer, tracked here for awareness.

See mrdoob/three.js#22785 for full description and test file.

Might be related to the recent slowdowns mentioned in #2915 regarding shader compilation - the attached file will probably cause a number of different shaders to compile.

[ghost]

This sounds like the threejs slowdown issue currently tracked by 2915.

Which browser are you testing on?

As a workaround you can pin v1.8 until our next release comes, e.g. <script type="module" src="https://unpkg.com/@google/model-viewer@1.8.0/dist/model-viewer.min.js"></script>

[hybridherbst]

It's Chrome on Windows, in the threejs issue a couple of related problems are linked - seems my poor little test file runs into multiple bugs in Chrome and threejs that together make it load forever.

[ghost]

Yes Windows is one of the main offenders, Chrome on OSX seems to be ok. Our only solution/workaround at the moment is to pin an older version model-viewer (which uses previous threejs) while this gets cleared up.