A non-halloween themed halloween post

    So this week's assignment, for me, has been to make some objects. Well I did that. I made 5 lamps, a barrel, and a crate, and I decided to do a quick lighting test, because I was worried that the models and textures alone didn't create enough definition. That worked out great.

    Afterwards, I decided to do a mid-scale test of the light-mapping workflow. That didn't work so great. at all. I had 2 problems: time and quality. As it turns out, baking light maps in Maya takes considerably longer than the equivalent render, for some reason. I don't know why. Well, I can see it taking a bit longer, but not as much as it does. Secondly, it took a 4k light map texture just to look acceptable. Mind you, that was only for those 7 objects, not including the floor. The problem was really just texture bleeding. Both from the space in between UV shells, and internal, hard edges. The result was that edges that were cut were outlined with black, which is fixable in Photoshop, and edges that weren't cut looked soft. If the light across an edge gets blurred, it looks... blobby. Not cool.
  
    So that pretty much murders the whole light mapping idea entirely, unless someone else has a better idea of how to go about it, which is sad, because that means we can't do nearly as much cool stuff with lighting. It wasn't a total loss, though. I still figured out how to do make the lamps work in XNA. In Maya, I used incandescence maps to fake back-lighting on the paper, there. Essentially, incandescence just adds directly to the result color. That is, if lambertian shading is light * diffuse color (where light is sum( light vector . surface normal) across all lights), then lambertian shading with incandescence is light * diffuse color + incandescence. Using what I learned from writing the light map shader, I could pretty easily modify a lambert shader to include incandescence.