Re: What about a GtkGlCanvas widget ? (Re: ANNOUNCE: GtkGLExt 0.3.0)

[Naofumi Yasufuku <naofumi yasufuku net>]

Hello Martin,

At Sun, 23 Jun 2002 13:54:14 +0200,
Martin Quinson wrote:
> 
> Hello, I've been playing a bit with gtkgkext, and I like it very
> much.

Thank you ;-)

> Still, I think it's too low level (as GL is). I dream of a GtkGlCanvas
> widget a generic engine to draw structured graphics in GL like the gnome one
> for 2D. 
> 
> I think we should have 3 distinct hierarchies of objects, interacting with
> each other: 
> GtkGlCanvas: Contains objects. It's the world. It's not even a visual widget. 
> GtkGlCamera: Is a view of the world. This widget is gl-enabled. 
> GtkGlItem: Something we put on the canvas.
> 

> 
> I'm not sure you'll need to have several subtypes of both GtkGlCanvas or
> GtkGlCamera, but GtkGlItem could be derivated, of course. I think of sphere,
> cube, cylindre, or even lw_obj (like in my example), or 3DS, all of them
> being child of the base item type.
> 
> Having a navigator would be as easy as attaching a preexisting function to
> the camera signals "button_click" "button1_move" "button2_move"
> "button3_move"...
> 
> I think this all would really ease the programming of the few gtkglarea
> program I've found out there.
> 

It is very useful for a lot of 3D programs.

I think the things you say will be a kind of GTK(or GNOME)-based 3D
application framework, and should be provided separately from GtkGLExt.
But I feel a great interest in it.

I also think the framework may be more exciting thing if it is based
on GNOME instead of GTK. I can imagine GnomeCanvas3D and GnomeCanvas3DItem.

For example, you can design 3D object on some GNOME-based 3D modeler,
and drag-and-drop the 3D object to another GnomeCanvas3DItem-aware
animation authoring tool.
GnomeCanvas3DItem will marshal and unmarshal the 3D object automatically.

It sounds exciting, doesn't it?

> 
> Don't get me wrong this mail is in between a feature request and a
> description of what I plan to implement. I have really no experience in GL
> programming, and very few in gtk/gnome programming (but I'm quite fluent in
> C). This is what I would love to have in order to make gl rendering easily,
> but I'm not sure I'll have the time and the motivation to actually implement
> it.
> 
> I'm actually at try to implement it, borowing most of the code from the
> lightspeed project, which already implement it more or less. I've no idea if
> I'll success in it...
> 

I recommend that it should be started as a new project.
If you are going to do it, I will help as much as I can.

Regards,

-- 
Naofumi Yasufuku  <naofumi users sourceforge net>
"The best way to predict the future is to invent it." -- Alan Kay