2nd submission:

added a composite 3d object and lighting effects

translations and rotations:
	   
- the implicit assumption is that the origin is in (0,0,0);  
- the first movement is just a sequence of translations
- the second movement is a rotation around a point (center of cube), in
 vertical plane; the 3 steps involved are, in this order:
	  1. translate origin to center of rotation T(r)
	  2. rotate by desired angle in vertical plane (the normal is half
- way between x and z in xz plane ==> (1,0,1) R
	  3. translate back T(-r)