When drawing in perspective, I've started doing some thinking, and I'm hoping my theory is corroborated!
With 2- and 3- point perspective, will all subjects be situated between the 2 or 3 vanishing points?
I ask because I've been practicing my cubes in perspective. For whatever reason, I plopped two VPs onto my horizon line, occupying about the left 2/3s of the page and drew a couple [cubes]. Once I had 2 of the little buggers and a sad ellipse, I looked at the other side of the page, void of cubes or ellipses! As I drew the formost edge for yet another cube, I stopped -- can I draw a cube here? The same rules don't seem to apply.
If this is too confusing (admittedly, I kinda confused myself here), just ask and I'll try to give the best clarification.