Felix Wiemann wrote:
> 
> Hi,
> when I use anti-aliasing and treshold 0.0 (+A0.0) with an empty (black)
> scene, every pixel is super-sampled. The doc says every pixel which differs
> *more* than threshold is sampled, but that's not true. Try +A0.001: No pixel
> is sampled anymore!

Um. If all your pixels are the same color, then none of them have any
difference from each other greater than zero. Duh.

Are you implying that the docs are in error by not saying "equal to or
more"? If so, you may be correct.

> Now I use the recursive AA method (+AM2) and use a depth of 2 (+R2). The
> messages say: 16.06 (@160x120) / 16.01 (@640x480) samples are taken per
> pixel. This is dependent on the resolution, so the pixels in the edges seem
> to be handled in a different way. The doc says: At a depth of 2 the maximum
> number of taken samples is 25!
> 
> Why are the pixels at the edges sampled in a different way than the others
> with method 2 (but not method 1)?
> Why isn't the maximum number of samples taken?

Because that's how recursive AA works; instead of blindly supersampling
everything within a pixel's area, the algorithm attempts to find edges
and only use the samples that are needed to better define those edges,
while interpolating the rest.

Check the docs again. The explanation is a bit hard to understand if you
don't already understand it, but the answers you seek are there.

-Xplo

Post a reply to this message