
     Add a Moveable Far Clipping Plane to the Renderer


The last renderer transformed the camera's near plane, z = -near in
camera coordinates, onto the homogeneous clipping plane w - z = 0.
That gave the renderer a moveable, front clipping plane.

In this renderer we will add to the clipping algorithm the homogeneous
clipping plane w + z = 0 and we will add to the camera class a far plane,
z = -far in camera coordinates, that is transformed by the projection
matrix into the new homogeneous clipping plane w + z = 0.

There are two main advantages to having a far clipping plane,
  1) eliminate needles processing of far away geometry,
  2) better depth resolution.




The only files changed in the renderer are
   Camera.java
   Clip.java
and the projection matrices
   PerspectiveProjectionMatrix0.java,
   OrthographicProjectionMatrix1.java.

The client programs are changed to make use of the new feature of
a moveable far clipping plane.
