After getting lights even vaguely working for alias models, I realized
that it just wasn't going to be feasible to do nice lighting with
forward rendering. This gets the bulk of the work done for deferred
rendering, but still need to sort out the shaders before any real
testing can be done.
I've decided that alias model skins should be in a single four-level
array texture rather than spread over four textures, but there's no way
I want to write that code again: getting it right was hard enough the
first time :P
