This is the first of four contracted "Hero Assets" for Khronos Group's 3D Commerce, a pair of sunglasses with an iridescent coating and featuring:

* Efficient 3D modeling.
* Face-weighted vertex
normals for clean
shading and optimal
compression.
* Optimal texture
packing.
* glTF extensions
iridescence,
transmission, and
volume.
* No ambient occlusion applicable since it is mostly metal and glass.
* Extensive tutorial for asset creation in the readme.

Added information to the readme about the texture format decisions.

WEBP case changed to WebP

Added CC-BY-4 license for all images in the README.md