Wonderful idea!  Thanks.

I knew that the textures were developed for pre-gamma support, but didn't
think to simply translate everything in the color_map ...

--John

Jerry Anning wrote in message <36e7ec62.3365811@news.povray.org>...
>On Thu, 11 Mar 1999 01:49:38 -0600, Bob Hughes <inv### [at] aolcom>
>wrote:
>
>>I've just done several different test renders (single light_source color
>>rgb 1) using Display_Gamma=1.0, assumed_gamma 2.2 and opposite of this,
>>also both as 1.0 or 2.2. The appearance changes drastically as you might
>>guess. Unfortunately to my eyes the render doesn't seem quite right when
>>used as suggested.
>
>If you are using pigments from color.inc, remember that many of them
>were created before POV had gamma correction, mostly on pc's with
>gamma 2.2 or so, and are designed to look "right" with that gamma.
>Thus, if you use assumed_gamma 1.0 (the Right Thing to do), you will
>need to alter them accordingly.  This also applies to most of the
>other standard includes (woods, stones, metals etc.).  Here is a
>little macro I have used for the purpose.
>
>// Begin POV code
>
>#macro Fixcols(Badcol)
> color rgb <pow(Badcol.red, 2.2), pow(Badcol.green, 2.2),
>pow(Badcol.blue, 2.2)>
> filter Badcol.filter transmit Badcol.transmit
>#end
>
>// End POV code
>
>Just wrap it around the color to be adjusted thus, for example:
>
>pigment { Fixcols(HuntersGreen) }
>
>
>Jerry Anning
>clem "at" dhol "dot" com

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