From: Alexander Peyser (
Date: Wed Feb 23 2005 - 16:01:19 CST


Yes, internal Tachyon behaves in the same way. Looking at more images
closely, the gray regions aren't at 0.5, they're at 0.75 and 0.25. 0.5
is actually green.

Another interesting feature is that the gray area has sharp boundaries.
There's a region around 0.25 and 0.75 which is exactly gray, and normal
behaviour (R->G->B) outside of those zones.

Alex Peyser

John Stone wrote:
> Alex,
> Do you have a similar problem if you render the image with Tachyon, or
> is this specific to just POV-Ray?
> Thanks,
> John Stone
> On Tue, Feb 22, 2005 at 07:34:47PM -0000, wrote:
>>I'm attempting to render a vmd scene composed of spheres colored with the User
>>method, in pov-ray.
>>When rendered in OpenGL, I get the proper mapping of User values to Color, a
>>smooth mapping from red for min, green for mid and blue for max. However, the
>>.pov file produced by vmd is mapping the mid colors to
>>rgbt<0.350,0.350,0.350,0.7>, which is gray instead of green. The min and max
>>colors are mapped properly to red and blue, respectively.
>>I have been able to test with 1.8.3 and 1.8.3b.
>>Alex Peyser

Alexander Peyser ( <>)
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