incorrect textures in Adobe Aero from glb generated by three.js GLTFExporter

[kfarr]

This behavior is consistent with observed behavior in other third-party applications such as ray tracers that use an older version of gltf loader (perhaps v1 instead of v2) that does not support some of the texture / uv mapping features assumed existing when generating the glb.

User issue1:

For some reason the export to GLTF, trees import as ‘ghost gray’ into Adobe Aero. My workaround is to just import trees and place them in the scene in Aero directly.

User issue2:

For some reason, a yellow street dividing line exported when I had no such line in my street design. It’s like the center line exported and it looks like a double yellow street divider. The street I was exporting just had one drive lane that was 16’ or so rather than two 8’ lanes, but the export still had the middle yellow line even though there was no middle yellow line in the 3D Street scene.

Dev questions:

• is there any case where it makes sense to generate a backwards compatible "gltf 1" version? is that even possible? Is that antithetical to optimization of glb file size?
• Alternate transmission format - would it make sense to consider conversion to usdz? Is that sacrilegious?

[Marc-Schloss]

I was playing around with Adobe Aero again in prep to talk with some city officials, so was working on a new street and thought I'd show this issue again, but with a screenshot from 3DStreet and one from Aero, showing the magical yellow line appearing in both the bike lane and the car lane, both of which are wide, single direction lanes without need for a yellow dividing line.

[kfarr]

In a gltf file, KHR_texture_transform is what defines how textures repeat.

The guess is that they have partial or no support for this specific extension.

Workarounds:

• Bake the UVs if that is a problem
• Ask Luke Walker what is the process he uses for importing 3dstreet glb and export via blender to aero

Other next steps:

• Use official model from Khronos that is not rendering as expected for this specific extension, here they are: https://github.com/KhronosGroup/glTF-Sample-Models/tree/main/2.0/TextureTransformTest and https://github.com/KhronosGroup/glTF-Sample-Models/tree/main/2.0/TextureTransformMultiTest