Am 20.06.2010 01:35, schrieb SharkD:
> I just rendered the following scene and noticed that no antialiasing
> appears around the shadow edges, despite having the feature turned on.
> There does seem to be antialiasing going on where the objects meet the
> background though. Is this a bug?

No, it's just the way AA currently works.

In POV-Ray 3.6 with assumed_gamma 1.0, and POV-Ray 3.7 until beta 37a, 
AA is based on linear brightness differences; however, the perception of 
aliased details follows quite non-linear rules. As a result, you either 
get visible aliasing artifacts at edges between moderately-dark and 
very-dark areas, or waste a lot of time "over-anti-aliasing" edges 
between moderately-bright and very-bright areas.

Future versions of POV-Ray will therefore use a non-linear 
(gamma-law-based) threshold for anti-aliasing.

(Earlier versions of POV-Ray, as well as POV-Ray 3.6 with assumed_gamma 
2.0, also effectively used a gamma-law-based anti-aliasing threshold and 
were therefore less prone to such artifacts, but this was just a side 
effect of the absent gamma handling.)

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