in unreal tournament 2003 they have these nifty projective textures in the game that show on EVERYTHING. its a very neat effect and it appears to be very fast because doing stat render in the console shows there are usually about 10 in a view. it also uses them for decals which means they have to be pretty fast. basically its a texture that gets projected onto the scene and shows up on your weapon or other players and the levels. its dynamic too, not something precalculated because they''re used for decals, so i''m wondering if Direct3D or OpenGL has functions to help do this? i also know ut2003 uses stencil buffers a lot but doesn''t appear to have anything that uses them, could this be it?

sweet, thanks.