I would like to have an ability to set texture coordinates for arbitrary virtual texture units (one axis), AND bind some of them to real ones (second axis).
This gives me an opportunity to create display list for geometry and dynamically switch TexCoord sets.
E.g., 3D Studio MAX-like blend shader.
I’ll be able to use THREE sets of texture coordinates (1st diffuse, 2nd diffuse, and opacity) but render it in two passes (1st diffuse+opacity, 2nd diffuse+opacity).
Now I have to use dynamic geometry on cards with maximum texture coords == 2.