[cairo] Pixels Are Not Little Squares

[Lawrence D'Oliveiro]

On Sun, 24 Apr 2016 18:07:01 -0700, Krzysztof Kosiński wrote:

> As far as I know, Cairo does use an approximation of the box filter
> when sampling polygons, or at least does so by default.

The available antialias settings for drawing shapes and text are
documented here
<http://cairographics.org/manual/cairo-cairo-t.html#cairo-antialias-t>.
In my experience, the DEFAULT setting seems to be the same as BEST (not
FAST, as you might expect).

If there is a setting corresponding to a box filter, I would expect it
to be FAST.

> The "little square" model is not a good general description of how
> image processing works, but it is reasonably good lie-to-children when
> discussing box-filtered sampling.

These “children” who aren’t getting the results they expect won’t
like being lied to.