Steve wrote:
> I got the "funny feeling" that POV wasn't averaging the blur samples
> correctly.  ...<snip>...
...snip...
> (gamma_correct(color1)+gamma_correct(color2)+gamma_correct(color3) ... )/n
> DOES NOT EQUAL
> gamma_correct(color1+color2+color3+color4 ... )   / n

Ha, I discovered this when I wrote my first dispersion patch (not the
current one, which is simple and works, but one I wrote in 1997).   I
couldn't get images to look decent even when i wasn't using dispersion,
but i had changed all the COLOUR types to a 9-component array, and had
to change loops,etc.   Antialiasing, focal blur, radiosity, and other
features all went nuts. 

Funny how this bug sat there for so long without notice.  Even though I
bumped into it, i assumed it was a flaw in my patch.

I hope all the usual people catch on and spread this fix.


-- 
Daren Scot Wilson
dar### [at] pipelinecom 
www.newcolor.com
----
"A ship in a harbor is safe, but that is not what ships are built for"
                                            -- William Shedd

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