xr-environment attribute causes errors the second time a webxr session is started

[LR17]

Description

When using xr-environment attribute, reopening a webxr session (after having closed a previous one)
causes NPE errors in the console

Live Demo

https://modelviewer.dev/examples/augmentedreality/#ar

Version

• model-viewer: v3.4.0

Browser Affected

• Chrome, version: 117
• Edge
• Firefox
• IE
• Safari

OS

• Android
• iOS
• Linux
• MacOS
• Windows

AR

• WebXR
• SceneViewer
• QuickLook

[elalish]

@bialpio @toji Can you repro this on your devices?

[toji]

I can't repro on my devices. Also, I'll note that Chrome 117 is fairly old, having been released 7 months ago. The current release is 124. If @LR17 can update to the latest version and try again, I'd appreciate knowing if it still repros for them!

[LR17]

Yes, same error, also with chrome 123

[toji]

Thanks for confirming! I tried it again this morning and I still can't provoke the issue that you're talking about. Could you also provide the device that you're testing with and also the version of ARCore that's installed on your device? (You can find this by going to Settings->Apps->See All->Google Play Services for AR. The version is listed at the bottom.)

Also, when this error appears does it cause a noticeable disruption to the AR content? (Black screen, no model shown, corrupted display, etc?) Or does the model display as expected and the only indication of a problem is the console messages?

[LR17]

It's a Samsung tablet SM-X200
ARCore version is 1.41.233110993

When the error appears the model is still shown but I suspect the light estimation feature is not working properly

[toji]

Thank you again! I really appreciate your willingness to follow up on this.

I'm guessing this is the device that you're referring to. If so, then it should be an ARCore supported device, according to the official support list. There's no compatibility notes listed there indicating that lighting estimation may not work or anything like that. The GPU is relatively low-end so it's possible that it's just not able to keep up with lighting estimation and AR tracking at the same time, but I'd sort of expect there to be a note to that effect it that were the case.

As for the ARCore version, I have a slightly newer one on my devices (1.42) so you may want to see if there's any updates available for "Google Play Services for AR" in the Play store, but it's not too old so I'd be somewhat surprised if that was contributing.

@elalish: I'm going to guess that this particular device is getting into a state where it's either not providing valid lighting estimates or providing them at a lower/more erratic rate, and that's throwing off either Chrome's implementation or Three's/model-viewer's expectations. Worth looking at the Three code first to see if there's any bad assumptions being made about consistency of lighting estimation data being provided. (If so it's probably my fault, I think Three is still using some of my code for that.)