Re: Again a canvas question

[Lauris Kaplinski <lauris helixcode com>]

> On Wed, 15 Nov 2000 10:06:30 Nathan Hurst wrote:
> > On Wed, 15 Nov 2000, Florent. Devin wrote:
> > > I have to draw 3D figure. For this I use GnomeCanvas.
> > > I have to do some rotation to show the different facet.
> > > Is there a way to do a 3D rotation, or have I to do rotation,
> > > and projection ?
> > 
> > You would have to do this yourself.  Gnome canvas isn't really the tool
> > for this - I would suggest you look at OpenGL(Mesa) for this sort of
> > functionality.
> 
> Mesa or another OpenGL library will do wonders. There is also a GL drawing
> area widget for gtk (the package is called gtkglarea) which will help you
> to access OpenGL within the GTK architecture.

Yeah. OpenGL does wonders, but if translated to 2D world, it's functionality
is more comparable to plain X than to those of GnomeCanvas. I.e. you have
to maintain all graphic state in client-side, and redraw your objects from
that data.

If you want to go easy way, you need some scene-graph library. There
are many free ones to choose: plib, CrystalSpace, OpenInventor...
If you are adventurous, then I once started Gtk+/C object-based scene
graph library Floyd (all aforementioned libraries are in C++) - but
its functionality is very limited at moment.

Regards,
Lauris