[Gnome-print] printing Images using pixbufs ..

[Chema Celorio <chema celorio com>]

After discussing this issue with both Lauris & Federico
I believe that we should encourage all gnome-print apps
to use pixbufs for printing images. There are a number of
advantages for using pixbufs, the main one is that we don't
have to copy the images while printing. So the way the pixbufs
are going to be handled are :

1. App passes pointer of pixbuf to GnomePrintContext
2. Context refs the pixbuf
[App is responsible for not changing the pixbuf while
gnome-print has a reference to it]
3. The gnome-print driver uses the pixbuf and prints the job
4. The pixbuf is unrefed

For the current images functions, gnome-print will create
(internally, transparent to the app) a pixbuf when the printing
of that image is requested and it will be unrefed (destroyed too)
when the printing is done.

Any comments ?

Chema