NAME: 			backface
 
 CELL CONTENTS:
 	Each cell contains two facets.  Both facets are at the same
 	Z value.  Neither facet contains per-vertex or per-facet 
 	attributes.  HLHS_removal is always disabled.  The two facets
 	overlay.  The upper left of these facets occludes the lower
 	right one.  The upper left facet is front facing while the
 	lower right one is backfacing.  Within a cell all attributes 
 	are constant, however some attributes will affect the
 	frontfacing facet and others will affect the backfacing facet.
 	Of the 28 variations of this test the output primitive used to 
 	create the facet is:
 
|	(backface.v01 - backface.v04) use "Polygon" as the facets.
|	(backface.v05 - backface.v08) use "Polygon3" as the facets.
|	(backface.v09 - backface.v10) use "Fill_area_set" as the facets.
|	(backface.v13 - backface.v16) use "Fill_area_set3" as the facets.
|	(backface.v17 - backface.v20) use "Triangle3" as the facets.
|	(backface.v21 - backface.v24) use "Quad_mesh3" as the facets.
|	(backface.v25 - backface.v28) use "Index_polygon3" as the facets.
|	(backface.v29 - backface.v32) use "Non_uniform_bspline_surface" as the facets.
 
 CELL LAYOUT:
 	Cells are arranged on the screen in a matrix of 5 rows and
 	6 columns.
 
 CONSTANTS:
 	Background_color		.3 .3 .8
 	Background_color_index		16
 	Edge_color 			1  .8  .6 
 	Edge_color_index 		17 
 	Interior_style			solid
 	HLHS_Removal			hlhs_disable
 	Edge_flag			enable
 	Edge_type			0
 	Edge_width			1
 	Interior_shading		1
 	Interior_lighting		1
 	Define_color %  i	 red	green	blue	         %
     	 		8	 1	0	0	% Red	 %
     	 		9	 0	1	0	% Green  %
     	 		10	 0	0	1	% Blue	 %
     	 		11	 1	1	0	% Yellow %
     	 		12	 0	1	1	% Cyan	 %
     	 		13	 1	0	1	% Magenta%
     	 		14	 1	1	1	% White	 %
     	 		15	 0	0	0	% Black	 %
     	 		16	 0.3	0.3	0.8
 			17	 1	0.8	0.6 
 
 			20  	 0.00 	 0.00 	 1.00
 			21  	 0.25 	 0.00 	 0.75
 			22  	 0.50 	 0.00 	 0.50
 			23  	 0.75 	 0.00 	 0.25
 			24  	 1.00 	 0.00 	 0.00
 
 			25  	 1.00 	 1.00	 0.00
 			26  	 0.75 	 1.00	 0.25
 			27  	 0.50 	 1.00 	 0.50
 			28  	 0.25 	 1.00 	 0.75
 			29  	 0.00 	 1.00 	 1.00
 
 	Text_prec			Stroke
 	Char_exp			1
 	Char_height			30
 	Text_color			1 1 1
 	Text_color_index		14
 
 PER FILE VARIABLES:	( See also Appendix B )
 	Devault_view_specification	parallel/perspective
 	Configuration			true_color/pseudo_color
 
 COLUMN VARIABLES:
 					Column
 			1	2	3	4	5	6
   Variable:  		____	____	____	____	____	____ 
   Backface_processing
     identify_backface	0	0	0	1	1	1
       (0=BACKFACE_IGNORE   ) 
       (1=BACKFACE_IDENTIFY )
     iculling		0	1	2	0	1	2
       (0=CULL_NONE         )
       (1=CULL_BACKFACE     )
       (2=CULL_FRONTFACE    )
   Call/Execute		Exec	Call	Exec	Call	Exec	Call
 
 	
 ROW VARIABLES:
 
   Row	Interior_color		Backface_interior_color
 
   1	0.00  0.00  1.00	1.00 	 1.00	 0.00
   2	0.25  0.00  0.75	0.75 	 1.00	 0.25
   3	0.50  0.00  0.50	0.50 	 1.00 	 0.50
   4	0.75  0.00  0.25	0.25 	 1.00 	 0.75
   5	1.00  0.00  0.00	0.00 	 1.00 	 1.00
 
   Row	Interior_color_index	Backface_interior_color_index
 
   1	20			25
   2	21			26
   3	22			27
   4	23			28
   5	24			29
 
 
 ROW/COLUMN VARYING VARIABLES:
 	NONE
 
 COMMENTS ON PHOTOGRAPHS:
 
 	*  Backface processing is being ignored in the photographs.
 		What you should see is depicted below:
 
   ______      ______      ______      ______      ______                
   |     |__   |     |__   |     |__   |     |__   |     |        ______   
   | 20  |  |  | 20  |  |  | 20  |  |  | 20  |  |  | 20  |        |     |  
   |_____|20|  |_____|20|  |_____|20|  |_____|25|  |_____|        |   25|  
      |_____|     |_____|     |_____|     |_____|                 |_____|  
   ______      ______      ______      ______      ______                
   |     |__   |     |__   |     |__   |     |__   |     |        ______   
   | 21  |  |  | 21  |  |  | 21  |  |  | 21  |  |  | 21  |        |     |  
   |_____|21|  |_____|21|  |_____|21|  |_____|26|  |_____|        |   26|  
      |_____|     |_____|     |_____|     |_____|                 |_____|  
   ______      ______      ______      ______      ______                
   |     |__   |     |__   |     |__   |     |__   |     |        ______   
   | 22  |  |  | 22  |  |  | 22  |  |  | 22  |  |  | 22  |        |     |  
   |_____|22|  |_____|22|  |_____|22|  |_____|27|  |_____|        |   27|  
      |_____|     |_____|     |_____|     |_____|                 |_____|  
   ______      ______      ______      ______      ______                
   |     |__   |     |__   |     |__   |     |__   |     |        ______   
   | 23  |  |  | 23  |  |  | 23  |  |  | 23  |  |  | 23  |        |     |  
   |_____|23|  |_____|23|  |_____|23|  |_____|28|  |_____|        |   28|  
      |_____|     |_____|     |_____|     |_____|                 |_____|  
   ______      ______      ______      ______      ______                
   |     |__   |     |__   |     |__   |     |__   |     |        ______   
   | 24  |  |  | 24  |  |  | 24  |  |  | 24  |  |  | 24  |        |     |  
   |_____|24|  |_____|24|  |_____|24|  |_____|29|  |_____|        |   29|  
      |_____|     |_____|     |_____|     |_____|                 |_____|  
 
 
 	The number indicates the color of the facet:
 
 		index	red	green	blue
 		-----	-----	-----	-----
 		20	0.00	0.00	1.00	
 		21	0.25	0.00	0.75
 		22	0.50	0.00	0.50	
 		23	0.75	0.00	0.25
 		24	1.00	0.00	0.00
 		
 		25	1.00	1.00	0.00	
 		26	0.75	1.00	0.25
 		27	0.50	1.00	0.50	
 		28	0.25	1.00	0.75
 		29	0.00	1.00	1.00
 
 	*  The text size (for the text at toe bottom of the screen )
 		was reduced from the size on the photograph.  Additional
 		information has been added to that text.

.