Projective texture mapping

Projective texture mapping is a method of texture mapping that allows a textured image to be projected onto a scene as if by a slide projector. Projective texture mapping is useful in a variety of lighting techniques and it is the starting point for shadow mapping. Projective texture mapping is a method of texture mapping that allows a textured image to be projected onto a scene as if by a slide projector. Projective texture mapping is useful in a variety of lighting techniques and it is the starting point for shadow mapping. Projective texture mapping is essentially a special matrix transformation which is performed per-vertex and then linearly interpolated as standard texture mapping. Historically, using projective texture mapping involved considering a special form of eye linear texture coordinate generation transform (tcGen for short). This transform was then multiplied by another matrix representing the projector's properties which was stored in texture coordinate transform matrix. The resulting concatenated matrix was basically a function of both projector properties and vertex eye positions.