The front end of the raytracer consists of 
 1) main.c
 2) scene.c   (object intersection stuff -- in-out class)
 3) tree.c    
 4) 4D.c      
 5) sml.yacc   (parser for sml)
 6) boundvol.c
 7) classify.c
 8) primitive.c


 Questions --> see dan O'Donnell