I have made some changes to tpatt.c based
on our earlier conversation.  None of it
is too elegant (I am not too proud of the
code in "tpatt.c") but I hope it works for you:

 - have put in command line options for setting
   the pattern id and window origin/size.  Just
   type "tpatt" without any arguments to see the
   options.

 - have modified the "set_perspective()" function
   to support asymmetric viewing frusta.  In other
   words I use the "window()" function as opposed
   to the straight "perspective()" function.  This
   allows you to create asymmetric FOVs (in the
   case of your vertical +15/-25).  The FOVs are
   hard-coded into that function!

 - "draw_sphere()" draws the horizon line at full
   intensity white now, just so you can check its
   in the right place easily.  Have also adjusted
   the angular limits of the vertical/horizonal dots
   to match your display.

 - have compiled similar "tpatt_l" and "tpatt_r"
   versions with the appropriate "rotate" command.
   (line 253).

Cheers,
Tom
---
tom@reading.sgi.com
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