RE: Patch for GtkLayout (was: GnomeCanvas and zooming)

["Arjan J. Molenaar" <A J Molenaar xirion nl>]

> -----Original Message-----
> From: Owen Taylor [mailto:otaylor redhat com]
> "Arjan J. Molenaar" <A J Molenaar xirion nl> writes:
<snip>
> > > the flicker-avoidance and scrolling stuff now happens 
> automatically. I
> > > don't know if this has been done or not. I don't know if 
> it matters
> > > for this change...
>  
> > Can't GtkLayout be changed so that it will draw itself in during
> > idle time (just like other widgets)? 
> 
> Are you referring to the gdk_window_process_updates() call in
> gtk_layout_adjustment_changed? The call is in there, because, in my
> experience, it looks very bad if scrolling gets ahead of updating, so
> you always want to fill in the newly scrolled in areas once you
> scrolled.
> 
> Other widgets that scroll do the same thing.
> 
> I'm still not sure what gtk-layout freeze/thaw was supposed to do, but
> if you want to do simultaenous x/y updates, the standard technique
> would be to poke the values into both adjusments then call
> gtk_adjustment_changed and/or gtk_adjustment_value_changed on
> both. The first signal emitted will do all the updates of the layout,
> the later ones are only needed to handle the scrollbars.

Hmm.. That's indeed what GnomeCanvas does, only it updates one value, emits a "value_changed" and the changed the other value... I will change that so both "value_changed" signals are emited after the new x and y values are set.

Are there any other things I should take into account when changing GnomeCanvas?

Thanks,

Arjan