[cairo] API request: obtain the trapezoids that are outside of the surface

[Thorsten Behrens]

Yesterday, Bill Spitzak wrote:

> However it might be best to define Cairo as returning some box that surrounds
> the filled area, and that the exact algorithim is implementation-defined, and
> it may return something smaller than the control points. If somebody figures
> out a fast way to get a tighter box then they should be able to put it in a
> Cairo implementation.
>
There actually _are_ some better algorithms, yielding a closer bound. For
example, the 'fat line' approach by Sederberg, explained to some detail
in:

T. W. Sederberg and T. Nishita: Curve intersection using Bezier clipping.
In Computer Aided Design, 22 (9), 1990, pp. 538--549

FWIW,

-- 

Thorsten

If you're not failing some of the time, you're not trying hard enough.