Mesh with tangents has validation errors and breaking compression

[marwie]

Model exported with UnityGLTF has thousands of tangent validation error

draco compression fails with access out of memory exception for these models

model.zip

[hybridherbst]

Potentially related:

• Thousands of ACCESSOR_INVALID_SIGN in file that was exported at runtime prefrontalcortex/UnityGLTF#121

[pfcDorn]

Should not be related. The sign error was a Meta Avatar specific issue.
But i will take a look now.

[pfcDorn]

Ok, after some investigation, i would say it's a Unity Draco bug. The Tangent support is new in draco, maybe there are still some issues. Currently i can't test it with gltFast, because it's not using the new com.unity.cloud.draco package (only this is supporting tangents)
I will contact Atteneder for this issue :)

[marwie]

I think got it for meshes with or without draco compression when exporting with UnityGLTF (validation errors for tangents in the resulting gltf)

[pfcDorn]

Edit: no, Draco works fine. But he need to change the code documentation for proper use of the tangents. :D I found a hint in the draco changelog how to handle it correctly, now it works fine!

[marwie]

Sounds good - so export for draco compressed meshes is fixed?
I can't reproduce anymore with non-compressed meshes too so that would be the only issue

[pfcDorn]

yeah, is fixed :)