[cairo] Transform optimization

[Soeren Sandmann]

Jeff Muizelaar <jeff at infidigm.net> writes:

> > The "fetch-refactor" branch of this repository:
> > 
> >         git://freedesktop.org/~sandmann/pixman
> > 
> > contains a refactoring of some of the transformation code that gets
> > rid of a lot of gratuitous code duplication. It will likely be useful
> > as a starting point for optimizing the transformation code.
> > 
> > I will probably merge that branch soon unless someone tells me that it
> > would interfere with what they are working on.
> 
> This looks good to me, though I'm curious: what kind of effect does it
> have on performance?

There was some slowdown, but not enough to make cairo-perf-diff report
anything on any of the benchmarks, ie., it was less than 5% even on
the "mag" benchmarks that test bilinear filtering.

Soren