by HotWax » Tue Jul 31, 2007 3:37 pm
The feature is technically incomplete, but as it's been used for this purpose many times, I doubt it'll be removed any time soon.
IIRC, randy originally planned to have this allow separate "light volumes" to be stacked on each other, so for example you could have fog on the floor, or a beam of red light that slopes through the sector and only lights part of the objects within it.
Unfortunately, this turned out to be too difficult to implement properly. As it stands right now, all you can use it for is to change the lighting on the walls, floor, and ceiling. It does not affect the lighting of sprites at all, which really limits what it can be used to achieve.