Re: [Gnome-print] Re: [Gimp-print-devel] An introduction to gnome-print (fwd)

[Michael Sweet <mike easysw com>]

Lauris Kaplinski wrote:
> ...
> Huge bitmaps are needed every time, PS does not have necessary
> functions, so everything should be rendered in client-side.

PS doesn't have the necessary functions for *some* types of image
compositing functions.  That does not mean you need to send an
image for everything.

> AFAIK, even single alpha graphic on top of pageful of text results
> in need of sending full page as bitmap - because we cannot guarantee
> exact font (pixel-by-pixel) matching between client and server.

If you use the same fonts (e.g. Type 1 or TrueType fonts provided
by the X server and printer) then you'll get exact (+/- 1 pixel
usually) matches; you just need to use the scalable versions of
X fonts, and embed (or request) non-standard fonts in the PS
output.

As for sending a full page bitmap to a PS device, that will instantly
make GNOME apps look slow compared to the competition, and I don't
think that is what the current GNOME-print PS driver does...

> On the other side - there will always be software rendering in
> gnome-print libs, for:
> - overcoming PS shortcomings
> - generating pixmap print-previews
> The only way to leave this rendering out, would be to create CUPS
> driver?, accepting gnome-print metafile, as input. But this driver
> would need renderer, closely matched with other gnome-print. So I
> am not sure, if it would make things easier at all.

If you have defined a GNOME metafile format, a filter could easily
be created (even using the GNOME-print rendering code as needed)
to handle that print data and convert it as needed.

The advantage is that system resources, printer accounting, etc.
could all be managed by the printing system, and common printer
drivers, etc. could be used for both the GNOME output and the output
of other applications.  From the user's standpoint it would look the
same, but be a more efficient implementation (I assume the metafile
format would be < the size of a raw print file for most cases?)

-- 
______________________________________________________________________
Michael Sweet, Easy Software Products                  mike@easysw.com
Printing Software for UNIX                       http://www.easysw.com