Material Appearance Discrepancy between Windows and Android on glTFast

[wangyanmeego]

Description

There is a noticeable difference in the appearance of materials when viewing them on Windows versus Android platforms using glTFast. On Windows, the materials appear correctly. However, on Android, it looks like there's a layer of fog over the object's surface, which is not intended and differs from the expected rendering.

Steps to Reproduce

1. Import a glTF model using glTFast in a Unity project.
2. Build and run the application on a Windows machine.
3. Observe the material rendering, which appears correct.
4. Build and run the same application on an Android device.
5. Notice the difference in material appearance, resembling a foggy overlay on the object's surface.

the image on windows:

the image on Android:

[wangyanmeego]

Test on glTFast 5.0.0 and glTFast 6.0.1，Rendering Pipeline is URP 12.

[atteneder]

Hi,

Is it possible that you've been using DXTnm normal map encoding on Android? That would certainly explain the problem, as glTF normal maps are always XYZ.

See #553