Re: Layered Drawing Areas

[Paul Davis <paul linuxaudiosystems com>]

On Thu, 2006-06-15 at 13:11 +0100, Richard Vaughan wrote:
> Hi,
> 
> Has anyone managed to get multiple drawing areas to layer
> transparently ontop of eachother?
> 
> I am trying to create an app that looks like it will need 3 or four
> layers of information drawn ontop of each other - but I want to be
> able to work with the layers independantly, and I want to be able to
> see down to the bottom layer.
> 
> Using a fixed container I can have the layers (at least it seems to do
> what I think I want), but when I draw in a layer it seems to blank out
> the 'destroyed' area. Is there a way of setting the transparency, or
> linking the background image for the layer above to the layer beneath
> it?
> 
> If it changes anything I am using GPE on an Ipaq...

<BrokenRecord>
GnomeCanvas widget. 
</BrokenRecord>

GTK widgets do not (currently) support any notion of alpha transparency
or z-order (stacking). The Canvas does. It has no relationships with
Gnome other than those shared with GTK.

GnomeCanvas is no longer "supported", but as yet its successor has not
emerged and there are several contenders.

--p