On a related note, unless this has been changed since version 3.1, if you
output transparency to an image (like PNG), the following weirdness occurs:
a pixel whose ray passes through a 50% transparent object, and then hits the
background color will be colored 50% of the transparent object and 50% of
the background color. Then it is made 50% transparent.  What *should*
happen, however, is it should be 100% the color of the transparent object,
and 50% transparent. The background color shouldn't be a part of the pixel's
color, since the background itself is transparentness. This causes big
problems when you've got an object that's only 20% visible - the background
color dominates the pixel, but it should be dominated by the transparent
object. Again, the background color should be invisible, and the percent of
color that comes from the background should only serve to be the percent of
transparency of that pixel.

I dunno if this really qualifies as a "bug" that should be fixed.

--
- Slime
[ http://www.teja.nu/slime/ ]
[ http://www.teja.nu/slime/images/ ]
"Roy Schulz" <roy### [at] gmxde> wrote in message
news:3bb6df38@news.povray.org...
> I used alpha output with anti-aliasing but didn't get the desired result.
> The anti-aliased pixels didn't have alpha values somewhere between 0 and
1.
> Instead, they had values of either 0 or 1. So, it is impossible to render
> anti-aliased objects for later compositing.
>
> Roy
>
>
>

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