Missing geometry on scene-viewer

[MajorMeerkatThe3rd]

Description

When loading this model in the scene-viewer, parts of the geometry is missing. It should be three planes and three cubes, but only the three planes are visible. The GLTF seems to be in order, no issues when I check the model details on https://gltf-viewer.donmccurdy.com/. This does not happen in WebXR or when the scene-viewer was created via the model-viewer (with this page at least https://modelviewer.dev/editor/).

Is there a difference in how I load the scene-viewer compared to the example below? I couldn't find anything.

Live Demo

A very easy CodeSandBox to reproduce the issue: https://codesandbox.io/s/6rrwto

The model (three cubes and three planes): https://shapediverviewer.s3.amazonaws.com/v3/gltf/example.gltf

It works when I load the same model on the model-viewer editor and select "Default AR Mode to Scene Viewer". I looked at the code of the model-viewer and how the scene-viewer is loaded there and I could not find a difference.

Version

scene-viewer 1.0 / 1.1

Browser Affected

-

OS

• [ X ] Android
• [ ] iOS
• [ ] Linux
• [ ] MacOS
• [ ] Windows

AR

• [ ] WebXR
• [ X ] SceneViewer
• [ ] QuickLook

[elalish]

Can we have some screenshots of the difference between the two ways you launched scene viewer?

@AdrianAtGoogle Any ideas?

[MajorMeerkatThe3rd]

Hey @elalish ,

sure, so here you can see how it should look like and how it does look like when I start the scene-viewer via the model-viewer.

And here is how it looks like when loaded directly in the scene-viewer as I show in the CodeSandBox.

Cheers

[ukito-pl]

Hi, I am also experiencing this issue with missing geometry. Problem appears if more than one node has the same name! According to the GLTF spec, property "name" should not be interpreted as unique value, it is not even required. If I remove the name properties from nodes, everything works fine, but if two nodes have the same name it all breaks down. It really is a strange and very troublesome bug! Modifing all exsiting models to work around such a simple issue is a real pain.

Can we expect any fix soon?

[MajorMeerkatThe3rd]

Thank you @ukito-pl for finding what the issue is! Let's hope that there is a fix soon.

[MajorMeerkatThe3rd]

@elalish I tested it myself as well, it is really the name property of nodes. Once you remove the names (or assign unique ones), it works.

[jukibom]

Yep, verified here too - doesn't happen on a colleagues' old phone which hasn't updated SceneViewer (/Google app).

This model doesn't work, it breaks in weird ways (some submeshes become transparent, others fail to render entirely) Talia 1G.zip

This model works (same but manually edited the nodes with gibberish strings to make the names unique) Talia 1GTest.zip

Switching over to WebXR as a reasonable stopgap for now but SceneViewer still provides the best experience, sadly (especially on older devices)

[elalish]

@jukibom Can you give us some feedback on the experience delta? We'd really like to ensure WebXR has the best experience, so knowing the problem areas would be very helpful.

[jukibom]

Sure, I'll move that over to discussions to keep this clear (edit: https://github.com/google/model-viewer/discussions/2413#discussioncomment-3816595)

As for this issue, is there a way for this to be reported to Scene Viewer devs as a regression?

[elalish]

It's been reported and the regression identified. A fix should roll out over the next week or two.

[goout]

a same issue, hope on soonest fix

[kremisi]

I have a similar issue, hope it'll be fixed soon, I'm following this git to receive good news.