I was actually employed to work on this exact problem over ten years ago: before such 3D packages etc. were commercially available.
I'm afraid I cant tell you the equations- it was too long ago. And yes, it sounds like it should be text book but it wasn't when I worked on it.
Sorry I'm not much help- all I suggest is that you look up Affine Transformations.
The projective equations are actually quite simple, but rendering of the graphics is more of an art form.