Re: Emacs and Gnome Canvas

[Jan Djärv]

YAMAMOTO Mitsuharu skrev 2010-07-16 12.01:
> > > > > > On Fri, 16 Jul 2010 09:33:16 +0200, Jan Djärv<address@hidden>  said:
>
> > > 1. Don't draw during redisplay, but mark the updated area dirty so
> > > the upcoming exposure event can trigger the actual redraw for the
> > > area to be updated.
>
> > If some characters change attribute for example foreground color,
> > you have to draw it, there will be no expose.
>
> Whenever you need drawing outside exposure events, it should be
> replaced with addition of the dirty area.

What does "replaced with addition of the dirty area" mean?  The X server only 
sends expose events when it thinks that a (part of) an X window needs to be 
redrawn, for example when resizing.  Scrolling does not generate expose 
events, nor is there a way to generate one.  The case where the window is 
supposed to change in the visible region does not generate any expose event.

        Jan D.