Hello !
What do you exactly mean by "cubic faces"? I've done a lot of image processing scripts, all using only the GD libraries and the PHP functions, but really never heard of that concept ... if you could explain it to me, show me some sample maybe, I guess I'll be able to build it with clean php, and without imagemagik (which, by the way, I never actually used more than a bif of debugging and/or compiling as php extension into couple of servers where asked by clients).
Regards,
Dragos