Re: Emacs and Gnome Canvas (was: Emacs, QT and Cairo)

[Dirk-Jan C. Binnema <djcb.bulk@gmail.com>]

Hi,

>>>>> On Thu, 15 Jul 2010 09:55:53 +0300, Eli Zaretskii ("EZ") wrote:

  >> From: Óscar Fuentes <ofv@wanadoo.es>
  >> Date: Wed, 14 Jul 2010 23:24:03 +0200
  >> 
  >> I'm very interested on this. Which are those requirements that gnome's
  >> canvas can not meet?

  EZ> To answer that, we need someone with good knowledge of both the
  EZ> requirements of the Emacs display engine and of the features and
  EZ> possibilities of the Gnome Canvas library.  Do we have such an
  EZ> individual?

Note, gnome-canvas is being deprecated;
   http://live.gnome.org/ProjectRidley/CanvasOverview
has an overview of various alternatives.

As far as I know them, all these canvases are primarily designed for graphics,
with object, group/ungroup etc. It remains to be seen how well they would work
for large amounts of text, with maybe here and there an image. Performance
might be an issue.

Maybe something working on top of Cairo (as has been suggested) would work
better. Cairo also has the advantage of being multiplatform and widely used
(e.g., Firefox), which gives some indication of speed/capabilities. However, I
think quite a bit of work would be needed -- the Firefox rendering engine
(Gecko) might provide some insight.

For what emacs needs, I think that the various canvases do not really provide
much added value compared to 'straight' Cairo (or some other lower-level
system).

Best wishes,
Dirk.

-- 
Dirk-Jan C. Binnema                  Helsinki, Finland
e:djcb@djcbsoftware.nl           w:www.djcbsoftware.nl
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