-Textures with 0 height are not checked for wraps, this helps speed up multipatch columns.
-A useless call to R_FakeFlat has been removed.
-Slopes now use floats rather than doubles to calculate UV coordinates.
Two reasons:
- Makes it more straight-forward to add brightmaps to the non-power-of-two rendering functions.
- Made it easier to split off brightmap rendering. Hopefully improves performance, but I haven't thoroughly tested this.
