Re: porting Xlib/Motif apps to GTK+

[Roger Davis <rbd soest hawaii edu>]

On Wed, 29 Feb 2012, jcupitt gmail com wrote:

> You need a compositing model instead. Your draw window should be a stack of
> 2D layers. In your expose callback, paint that part of the window back to
> front. Do rubberbanding by creating a temporary top layer with the rubber
> band in and queueing refresh events for the pixels it touches as it moves.
> Very simple, reasonably efficient, easy to make flicker-free with gtk's
> automatic double-buffering.

Hi John, thanks for the followup. Excuse my deep ignorance on the topic 
but I'm just beginning to look into GTK/GDK/Cairo. Does the v2 release of 
this whole bundle include explicit support for the layering approach you 
describe, or are you talking about my code having to maintain this 
knowledge on its own (presumably by maintaining two separate drawing 
surfaces, with the primary image in one and my quasi-rubberband overlays 
in another), and explicitly overlaying them myself? What about the v3 
release?

Thanks!

Roger