On Tue, 27 Jan 2004 08:30:12 -0800, "Carl Hoff" <hof### [at] wtnet> wrote:
>Well my problem was with how POV-Ray determines which
>pixels didn't need AA.  With a threshold of 0.3 there were still
>pixels along the red outline of the turret/cannon where the
>test rays missed the thin red line and since AA wasn't
>performed the pixel was rendered without any red.  This made
>it look like there were breaks in the outline that I didn't like.

Well, zeroing the threshold certainly forces the issue.  Quite
inefficiently, though.

>The grid in the far background also looked better with a
>threshold of 0.

All discontinuous regular patterns show sampling artifacts if rendered
far enough in the distance.  This includes checkered planes, and since
everyone is required to make the hajj to the checkered plane, you
might search past articles to see what others have done.

The best "solution" i know of is to avoid rendering it, e.g., obscure
it with ground fog, place a wall in the near background, or aim the
camera downward a bit more.  It's akin to what Bible illustrators do
with Adam and Eve. ;-)  Focal blur will also do the trick, but that
can take forever, which is what we're trying to avoid.

>  I agree aside from those two areas I could
>have used the default 0.3.  The red outline is its own CSG
>in my image.  Is there a way in POV-Ray to have the pixels
>with rays that come near a particular object rendered with
>different AA settings then the rest of the image?

Not that i know of, but you can try making the lines thicker to
decrease the chance of the AA missing it.

Speaking of CSG, do you have a lot of intersections and differences?
Manually bounding these sometimes speeds things up.

>I've currently got Windows ME and I just did a search of my
>system for cjpeg.* and nothing turned up.  I also went to a
>DOS prompt and typed cjpeg and it tells me "bad command
>or file name".  According to the FAQ I should have this file.
>Is it named something else under Windows ME?

The FAQ doesn't say that you have it; it says that it's available.
It's a freeware program that you can download from the Internet.  See
http://www.faqs.org/faqs/jpeg-faq/part2/section-15.html for a
reasonably trustworthy download site.  N.B.:  Avoid using long
filenames with this program.

Alternatively, you can check the program that you used to convert your
first image to JPEG, to see if it has supersampling control.

-- 
------------------- Richard Callwood III --------------------
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