gMIL Occlusion Shader
by Eric A. Soulvie
*BetaForce Only Not for Release*

It'll become abundantly clear that I can't write docs.

Control overview:

Colour Add:  This control is the percentage of background colour that is added to the surface colour.  
This can be further modified by the amount of occlusion of the sampled pixel by other geometry.  

Sample Rate:  If set to '0' then the background colour is added to the surface regardless of occlusion. 
 If set to '1' then a single ray is fired along the surface normal to test for intervening geometry.  
If none is found than the background colour is add to the surface colour.  If set to '>1' then multiple 
rays are fired randomly from the surface.   The percentage of rays not hitting any geometry is multiplied 
by the Colour Add to determine how much of the background colour to add to the surface colour.

Occlusion Diffusion:  If 'ON' then the same percentage of rays hitting the background from the 
Sample Rate is used as a multiplier of the surfaces diffuse value.
 
Sample Style: 	Random:	A differant pattern of rays are fired for each sample.  Shading Noise Reduction 
		works with this option.
		Ordered:	The same pattern of rays are fired for eash sample.
