glTF2 models all using png instead of ktx2

[alecazam]

I thought ktx2 was a big part of glTF2 with support for compressed mips and block-encoded formats (or basis transcode)? I don't see any samples with ktx2 in use. png can't represent premultiplied alpha, mips, cube maps, array textures, 3d formats, and other elements that are important to 3d rendering.

[cx20]

It seems that the model currently using KTX2 is being submitted for PR and has not been merged yet.
#285
#292

These models have been experimentally tested with gltf-test and are also available here.
https://github.com/cx20/gltf-test

Also, for information on how to use KTX2, please refer to the following repository.
https://github.com/KhronosGroup/3D-Formats-Guidelines

[alecazam]

I also found the extension to load a restricted version of KTX2. This forces UASTC usage, but I'm looking to generate platform-specific assets that use KTX with BC/ETC2/ASTC textures.

https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Khronos/KHR_texture_basisu