Re: New GDK port: OpenGL

[Alex Larsson <alexl redhat com>]

On Mon, 13 Aug 2001, Derek Simkowiak wrote:

> 
>     Hello,
> 	I've written an OpenGL game engine that uses SDL for its input (it
> uses Quake2 BSPs for levels).  Now I need a widget library to build a GUI
> for my game.  I want the GUI to float above the 3D-rendered world,
> possibly with some alpha translucency.
> 
> 	If I understand correctly, I can port GDK to OpenGL (and an input
> and framebuffer library, such as SDL, glX, svgalib, or GLUT) and then GTK+
> will render to an OpenGL window.  I'll probably need to add some basic
> windowing code, like the framebuffer port.
> 
> 	This will produce something similar to GLUI, see:
> 
> http://www.cs.unc.edu/~rademach/glui/
> 
> 	I'd use GLUI, but it depends on GLUT and is missing some key
> widgets.  It seems like it'd be easier and more fruitful to port GDK to
> OpenGL+SDL than port GLUI to SDL and write some all-new widgets. 
> 
> 	I have some questions:
> 
> 1. Is this plausible?
Yes.
> 2. Are there any caveats I should be aware of?
The rendering API in OpenGL does not support a lot of the features of 
gdk/X, (e.g. wide dashed ellipses) so you'd have to implement a lot of 
code for this. OpenGL also has very bad screen reading performance.

> 3. What kind of timeframe should be expected?  Can this be done in 40
> hours?
No. I'd expect several months work.

> 4. What version tree should I start with?  The latest CVS...?
Latest CVS.

> 5. Who did the framebuffer port?  I'd like to ask them some questions
> about their porting effort, and their windowing code.
That would be me and elliot.

/ Alex