Scott Long ([EMAIL PROTECTED]):

> More smooth is not necessarily less "alias," as you put it. Smoothing
> filters work by spreading pixels values into surrounding pixels. The
> effect of this is to remove high frequencies from the image. But the
> goal of antialiasing is different. We don't want to make the resulting
> image smoother, per se, we want to make it more *accurate*. In other
> words, we want to consider pixel coverage on the sub-pixel level, and
> color pixels according to a more accurate scheme than "If the center
> of the pixel is covered, then the pixel is on."

  Perfect coverage information does not solve aliasing.  Integration
over the pixel area is equivalent to filtering with a box.  My standard
example to show this is a freehand stolen from Poynton's 'A Technical
Introduction to Digital Video':

  http://vektor.theorem.ca/graphics/integration-aliasing.png

  So, maybe the pixel values might be an accurate representation of a
percentage of an area, but it's not removing all aliasing from the
image. :)

-- 
Billy Biggs
[EMAIL PROTECTED]
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