Re: OpenGL terminal driver

[Robert H. <en...@no...>]

On Sun, 1 May 2005, Ethan Merritt wrote:

> Anyhow...
> I pursued it a little bit further using the debugger.
> The segfault came immediately upon attempting to call
> 	 int argc=0;
> 	 glutInit(&argc, NULL);
?
> My GLUT docs tell me that the arguments to this call
> *must* be the original (argc,argv) pair from the actual
> invocation of the running program.  And indeed if I hack
> those in then the program proceeds a little further.

ok. is there any clean way of passing the gnuplot argc,argv to this? I
couldn't see one, but I also know there isn't anything of interest to glut
there anyway. Perhaps I should pass argc=1, and argv[1]="gnuplot"?

> However, it then brings down the entire X-server before displaying 
> anything :=(   

So with a bit of work I might be able to erase the contents of your hard
drive too ;-) There are bugs in my GL_init() code, but I've never been
able to get worse than a segv out of it. I have however found that I get
different results/behaviour on my nVidia card at work than my ATI card at
home, so who knows what is possible.

> Perhaps that is due to the glutMainLoopEvent/glutMainLoop difference?

This approach really wont work.

glutMainLoopEvent takes a single pass through the glutMainLoop and
returns. This means everything stays in control of the calling program.

glutMainLoop transfers control of the program over to glut, and *NEVER
RETURNS*. Everything else is supposed to be done in callbacks. 

I guess if you make glutMainLoopEvent a no-op, and add a call to
glutMainLoop at the end of GL_text(), you would be able to do a single
plot, and then gnuplot would stop responding.

Rob



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