I just have to ask...
Anyone knows why uvs are vector 3 instead of vector 2? is it because vector 3 are more memory efficient or something like that? Is there any use for the 3rd float? anyone knows the answer to this?

In DCCs and renderers, texture coordinates were originally treated as generic 3D parameters, not strictly 2D UVs.

• For normal 2D textures you only use u and v.
  
• For 3D textures / volumetric lookups you also use w.
  

animatrix_
In DCCs and renderers, texture coordinates were originally treated as generic 3D parameters, not strictly 2D UVs.

• For normal 2D textures you only use u and v.
  
• For 3D textures / volumetric lookups you also use w.
  

Thanks. I was just curious of the origina of it. 😀