Once I saw this in action, I thought it was an intentional glitch and the light was being replaced with a clipping mask. This is rather cool.
Once I got it, I immediately saw a practical use for this kind of graphical trick: Add this in near the beginning of Doom 3 with a flaming skull ghost flying around the room, and instead of shining light, it's light radius shows a view into hell. Now THAT would be cool, although given Doom 3's sophistication, that would cause some drastic slowdown and probably crash a lot of standard rigs.
Once I got it, I immediately saw a practical use for this kind of graphical trick: Add this in near the beginning of Doom 3 with a flaming skull ghost flying around the room, and instead of shining light, it's light radius shows a view into hell. Now THAT would be cool, although given Doom 3's sophistication, that would cause some drastic slowdown and probably crash a lot of standard rigs.