
Let's say that there's a map, and on this map there is a building. Inside the building is completely dark, but outside, it's a bright sunny day. It'd be nice if I could just have the 'global illumination' apply to only the outside area, while the inside is dark. Not really sure how it could be implemented, but it would be convenient and nice, rather than having to set up a bazillion light sources outside, or set up an entirely separate map for indoors.