[cairo] cairo macros and public API

[Carl Worth]

On Thu, 2008-09-04 at 01:16 +0100, Chris Vine wrote:
> The tiff images are in fact whole-page fax images.  You can see the
> effect by loading a tiff image representing an entire page in eog, and
> then printing the page from eog (or viewing it from the preview button
> in the eog print dialog).  The length of the printed image will be
> about 5% too short, even with page margins set to 0.
...
> If you can get a fax sent to you the effect can be seen by comparing
> printed output using direct tiff to ps conversion (that is by not
> choosing to use the GTK+ print system in the efax-gtk settings dialog)
> and by choosing the GTK+ print system (which as in the case of eog uses
> cairo to render the pages in the draw-page callback). cairo overscales
> downwards by about 5%, which can be overcome by scaling back up by 5%
> by choosing 105% scaling in the print dialog.
>
> It doesn't appear to be a GTK+ problem,

Very interesting. I'd love it if someone could whip up a cairo test
suite case exercising this bug.

-Carl