Re: Problem with preview and the blocking print dialog

["John (J5) Palmieri" <johnp redhat com>]

On Wed, 2006-05-10 at 16:51 -0500, Federico Mena Quintero wrote:
> On Wed, 2006-05-10 at 17:42 -0400, John (J5) Palmieri wrote:
> > I'm implementing the preview code in gtkprint.  I have decided to use an
> > external helper (default is evince) to do print preview.  The idea was
> > to write out to a pdf in /tmp and launch the external helper when the
> > user hits the preview button.
> 
> <ignorant>
> 
> Why do we have an external helper?
> 
> Gnome-print would save everything to its own internal metafile, and then
> it would spit it to a gnome-canvas.  Could we make Cairo just render
> everything to a preview window?
> 
> </ignorant>

This was my original thought but Matthias and others suggested this.
One of the issues with cairo is that we would have to either run through
the drawing commands on every expose event or save out to a bitmaps
surface which would remove the ability to zoom.  The other option is to
recreate evince in gtk+.  That is not going to happen.

One thing we can do with the external helper design is send a signal to
the app which could then request to handle the preview itself.  The app
could then take the generated PDF and embed a pdf viewer like poppler,
avoiding complexity in gtk+ itself.

Either way I was going to design so we could add a canvas in the future.

-- 
John (J5) Palmieri <johnp redhat com>