Ive wrote:
> Strange. I've checked it and it seems to work, but I do not understand
why.
> From my knowledge, simple color blending within the RGB color space
> should always give that unwanted result, and I do not see what gamma
> correction has to do with it. Can somebody please enlighten me.

Suppose we're just "antialiasing" two pixels together, purple and cyan --
that is, rgb <1, 0, 1> and rgb <0, 1, 1>. If we antialias and then
gamma-correct, we get <0.730, 0.730, 1> which the monitor turns into <0.500,
0.500, 1>, the color halfway between purple and cyan. However, if we
gamma-correct and then antialias (as POV-Ray does), we get <0.500, 0.500, 1>
which the monitor turns into about <0.218, 0.218, 1> -- resulting in the
blue line.

Anders

P.S. Here's the original image gamma-corrected by 2.2. As you can see, the
unwanted colors are gone.

--
light_source{6#local D=#macro B(E)#macro A(D)#declare E=(E-#declare
C=mod(E D);C)/D;C#end#while(E)#if(A(8)=7)#declare D=D+2.8;#else#if(
C>2)}torus{1..2clipped_by{box{-2y}}rotate<1 0C>*90translate<D+1A(2)
*2+1#else}cylinder{0(C-v=1).2translate<D+C*A(2)A(4)#end-2 13>finish
{specular 1}pigment{rgb x}#end#end#end-8;1B(445000298)B(519053970)B
(483402386)B(1445571258)B(77778740)B(541684549)B(42677491)B(70)}

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