Color mapping problems on the 4D/25TG

[Jim Bennett]

In article <136 at tachyon.UUCP> roger at tachyon.UUCP (Roger Cordes) writes:
>
>    We have a color-map-related problem when our code is executed on the
>4D/25TG: in color map mode, a line drawn using a single color index will
>exhibit a rainbow effect, as though indices in the color map outside the range
>of those we use are being accessed. Obvious possible causes have been
>investigated (bit shift w.r.t current writemask, drawmodes, single/double
>buffer state, onemap vs. multimap, argument/value type checking and
>consistency) and eliminated. The code executes as expected on non-Turbo
>workstations:
>	color(col);
>	move(x1,y1,z1);
>	draw(x2,y2,z2);
>    This line is supposed to be a single color, and shows up as an
>interpolation between entries in another part of the color map.

You need a shademodel(FLAT) on the 4D/25TG to disable color interpolation.

>      | Roger L. Cordes, Jr.        |  Stephen Dedalus Incorporated    |
>      | ...!mcnc!rti!tachyon!roger  |  1150 SE Maynard Road, Suite 100 |
>      | (919) 467-7072              |  Cary, North Carolina  27511     |

Jim Bennett			(bennett at esd.sgi.com)