Re: [GtkGLExt] Is it possible to use overlays with gtkglextmm?

[Jose Commins <axora axora net>]

      You can try using 3D textures for volumetric rendering, it lends 
itself to layer-slicing quite well.

Regards,
         Jose.
> Message: 1
> Date: Tue, 09 Feb 2010 17:15:24 +0000
> From: "Haraldur Tristan Gunnarson" <harg pml ac uk>
> To: <gtkglext-list gnome org>
> Subject: [GtkGLExt] Is it possible to use overlays with gtkglextmm?
> Message-ID: <4B71982C 6040506 pml ac uk>
> Content-Type: text/plain;	charset="ISO-8859-1"
>
> Greetings,
>
> I have been writing, as my first significant project using OpenGL, a GUI
> using gtkglextmm for viewing large datasets as a cloud of points. I have
> some measuring tools that are currently rendered by drawing some of the
> points and then the line or box of the tool while the user is dragging
> the cursor. This works well with small datasets but gets sluggish with
> the larger ones, particularly the ones that require caching. I would
> like to use overlays as a conceptually and practically simple (I hope)
> way of drawing the rulers (and so on) without having to redraw the
> points each time.
>
> How do I do this while using gtkglextmm? I found the method
> Gdk::GL::Config::get_layer_plane() but no other obvious things in the
> documentation. Looking at an example using WGL, it appears I need to
> create an "layer context" for the overlay, but I do not see how to do
> that in gtkglextmm. Does it work in a similar way and, if so, how?
>
> Thanks in advance,
>
> Haraldur