[poppler] [PATCH] Use cairo transformations in cairo backend

[Kristian Høgsberg]

On 5/31/06, Jeff Muizelaar <jeff at infidigm.net> wrote:
> This patch changes the cairo backend to use the transformation support
> in cairo instead of doing all of the transformations in the
> OutputDevice. The primary motivation for this change is correctness but
> there are other benefits as well.
>
> Currently, both the splash and cairo backends do all of the
> transformations in the OutputDevice and so the actual rasterization
> process doesn't know about them at all. The problem with this approach
> is that the pen is not transformed. See #6948 for an example of the
> problems this causes, or for a quick example, imagine a thickly stroked
> curve that has been scaled only on the x-axis.
>
> Also, with this patch, the cairo backend will now for the first time,
> afaik, render some pdfs more correctly than the splash backend.

This looks good, I'm especially happy to get rid of all the duplicated
double[6] -> cairo_matrix_t conversions.  It's a nice cleanup in
itself, and since it also fixes the transformed pen issue, let's get
it in.

cheers,
Kristian