Textures not displaying properly if normal/base texture transforms don't align

[GitGhillie]

Bevy version

latest main (4dbfdcf)

Relevant system information

Windows 10

AdapterInfo { name: "AMD Radeon RX 7900 XT", vendor: 4098, device: 29772, device_type: DiscreteGpu, driver: "", driver_info: "", backend: Dx12 }

What you did

Export object from Unreal to gltf, with texture transforms enabled.
Load gltf with Bevy.

What went wrong

Using a gltf viewer it looks good:

However, in Bevy things look severely distorted:

Additional information

I've trimmed down the gltf and made a reproduction here: https://github.com/GitGhillie/bevy_repro/tree/broken-texture.
In Blender the shader for the material looks like this:

If you remove the Mapping node or copy it to the normal map such that both have equal transforms, everything looks as expected (except you destroy the art in the process).

There is a note in #11904 saying "Note the gltf crate doesn't expose the texture transform for the normal and occlusion textures, which it should, so I just ignored those for now". I'm 90% sure that's the issue but I don't have the experience to say for sure.

[janhohenheim]

Yep, pretty sure the missing fields in the gltf crate are at fault here. Marking as blocked for now.

[GitGhillie]

This one right? gltf-rs/gltf#412

[janhohenheim]

Exactly. Thanks for linking :)