Re: Emacs and Gnome Canvas

[Jan Djärv]

Eli Zaretskii skrev 2010-07-15 10.38:
> > Date: Thu, 15 Jul 2010 09:46:36 +0200
> > From: Jan Djärv<address@hidden>
> > CC: Óscar Fuentes<address@hidden>,
> >   address@hidden
> >
> > >    . Canvas redisplay is caused by requests from the application to
> > >      update some "canvas item" when the underlying application's objects
> > >      are modified; these requests are then served when GTK+ idle
> > >      handlers are run.  Emacs display engine works differently: changes
> > >      that require redisplay are not considered until redisplay is
> > >      entered; the "requests" to update the display are implicitly
> > >      recorded in the buffers and in the various related data structures
> > >      (text properties and overlays, display strings, etc.), but not
> > >      explicitly translated to display terms until redisplay time, and as
> > >      an inherent part of redisplay itself.  These two very different
> > >      models will need to be reconciled in some reasonably efficient way.
> >
> > The changes that require redisplay would have to notify the Canvas that things
> > changed.  I think this style is more efficient.
>
> What do you mean by "changes that require redisplay"?  Suppose a
> character was inserted or deleted -- would that need to notify the
> Canvas?

Yes.

>  How about an arbitrary mouse move?

If it resulted in a different highlightning of a link, yes.

        Jan D.

>