In SuperDesktop mode the display might be driven with 1 pipe and 3 channels, or 3 completelyseparate pipes. (Note: a pipe refers to a graphics board, and a channel refers to a video output on a graphics pipe. SGI Infinite Reality systems usually allow 2 or 8 channels per pipe. Most other vendor hardware only has 1 or 2 channels per pipe.)
For a single pipe with three video channels each running 1280x1024 with 256 pixel overalp the IR combination will look something like this,
With this channel configuration the CAVELib configuration file should be setup to create a single projection plane such that its width is the arc length of the projection screen. Imagine the projection plane being a soup label that gets applied to a can.
Top down view of cylindrical screen, with corresponding virtual projection plane behind the physical screen.
For a display that has a 150deg total horizontal field of view, a 12' radius, where the screen is 1' off the ground and is 8' in height, the CAVELibn confiuguration file would like like this:
Walls screen0
WallDisplay screen0 :0.0 3328x1024+0+0
ProjectionData screen0 * wall -15.71 1.0 -12.0 -15.71 9.0 -12.0 15.71 1.0 -12.0 feet