Re: wxGLCanvas and an opengl terminal

[Ethan M. <merritt@u.washington.edu>]

On Sunday 22 August 2010 12:57:15 pm Richard wrote:
> Hi
> 
> I have a few weeks free and thought I would use it to write an opengl
> terminal for gnuplot. It's meant to make it fast to examine
> data/functions interactively. I don't know if anything like this already
> exists, but I can't find it on any of the forums/this newsgroup. Any
> help or suggestions much appreciated. I'll post a patch once the first
> draft is done.

It's great that you would like to contribute to the project.
It would help if you would lay out what you see as the advantages/goals
of the new terminal.  

I am concerned that you may be aiming for a  "true 3D" output device, 
and I think that's not going to work. The problem is that while gnuplot
does read in and process 3D coordinates, the API between the core
plotting code and the individual terminal drivers is only 2D.
That is, the core plotting routines calculate a 2D projection and
pass only the 2D coordinates to the terminal driver.  So you can't
just slot in a 3D terminal driver using the existing API.

That's not to say there is no path forward, of course.  Just that it
would require re-thinking the API and creating new code for a whole lot
more than just one new terminal driver.  Before pluging in to any 
particular 3D terminal driver, I'd like to see some discussion about
how to revise the API and the flow through the core plotting routines.
There would need to be a clean alternative path through the code that
avoids calculating a 2D projection, thereby losing the full 3D
coordinates.

	Ethan



-- 
Ethan A Merritt
Biomolecular Structure Center,  K-428 Health Sciences Bldg
University of Washington, Seattle 98195-7742