Re: [Freeglut-developer] Direct Rendering Contexts

[Stephen J B. <sj...@li...>]

Richard Rauch wrote:

> An interesting idea, but it would require a certain amount of
> hacking on freeglut to get freeglut to help you with this.  Or else
> you'd have to reach into freeglut's data structures from the client.
> (freeglut opens one, and only one, X display, I believe, and makes
> reference to it from time to time while running.  Also, having
> multiple displays/screens would make it unclear what to do for
> glutGet(GLUT_SCREEN_*) calls (height/width, in pixels and in
> millimeters).
> 
> The way to do this may be to leave it to user-selected, user-controlled
> tools.  (There are one or two tools at least for letting users share
> windows between X servers.  I've never gotten into them.)

This is something I've actually tried. (Two INDIRECT rendering contexts
on different computers being driven by one application on some kind of
a server).  Needless to say, I was writing this at the X-intrinsics level,
not using GLUT/freeglut.

These kinds of things get VERY ugly to code.  The problems start to arise
when (for example) one user has an nVidia card and the other an ATI.  They
each have different OpenGL extensions - so you can get into all sorts of
interesting and exciting problem areas with that stuff!  Heck, you can't
even rely on them running the same revision of OpenGL as you are running
on your server.

This is just *so* ugly.

> Another way to do it would be to simply run two copies of the applicaion
> and have them share data, possibly both doing direct rendering on their
> respective displays.

Definitiely!

I rapidly decided to write a client-side application and a server-side
application and to have the server know nothing about graphics or OpenGL.

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