[cairo] Extents under rotation

[Bill Spitzak]

On 12/05/2013 10:32 PM, Donn wrote:

> A question - will this mysterious rotational uncertainty principle (lol)
> return in situations like in_fill() ? I'd want to test my mouse against
> some path that is under a tree of matrix influences.

The matrices are multiplied before this is done, so this error does not 
accumulate. For instance if you rotate by 45 degrees and then back by 45 
degrees, it will act like a rotation of 0 and produce your expected 
bounding box, rather than enlarging the bounding box twice.