[Sir Stafford Cripps] has all the virtues I dislike
and none of the vices I admire. -- Winston Churchill

Concept 3.5 : Orthographic vs. Perspective
==========================================

Idea:
=====
Here we show the same objects viewed with by 
specifying an orthographic volume and a perspective
volume. 

Experiment
==========
Try different values for the various parameters and see
the effect for both Perspective and Orthographic 
Projection on the same objects.

Note
====
The sphere in the rendering is drawn after a translation
of -10 units along the Z axis.  The cube is drawn at the
origin.
Orthographic projection does not scale the sphere relative 
to the cube but the perspective projection does it (i.e. 
foreshortening for perspective)