Fixes#330
Also, fix incorrect patch application introduced by previous commit, it
would not read the patch color value, and could only switch the light
off.
Instead of passing model color around as an implicit global state, pass it per-model.
This makes it (a) easier to track, (b) easy to fix blending issues. E.g. this fixes incorrect coloring of brush and studio models, which is also different.
still not fully there:
- glow is slightly off
- TransAlpha has wrong blending mode
apparently pipeline settings for brushes, models, and sprites are substantially different, need different pipelines