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jpdamato
08-21-2003, 08:21 AM
Is there any way to work with three Monitors/Screens in an Opengl application under Windows?
Basically, in each screen, we need a different view of the application.

Obli
08-21-2003, 10:59 PM
Somebody told me that this question arises with a certain periodicity. Looks like it's not.
This is just "heard" however I myself read about three (possibly more) topics of this kind and replies were saying "no because windows does not allow it" or something like that.

al_bob
08-21-2003, 11:08 PM
If the monitors are connected to the same video card, then it's just a matter of creating the application windows at the right places.

If you're using video cards from multiple vendors or video cards that use different drivers, you're SOL; opengl32.dll will not dispatch the OGL calls to any drivers (or at least, I haven't found out how).

I have no idea about using multiple video cards that share a driver.

TheSillyJester
08-22-2003, 05:45 AM
Just some ideas, probably not true.

Seems to me that you have to create a new context and switch beetwen them, but it isn't a idea as context switching is really costly.
Maybe you have to get all the opengl fonctions drivers pointers at load time, then the switch isn't needed.

Antorian
08-22-2003, 06:40 AM
Multiple view (Fullscreen or windowed) on multiple cards isn't possible (some tricks allow you to make windows and place them on each window but don't work with fullscreen).
Actually it's impossible to switch Context between monitor 'cause you cannot access differents Device Contexts with only one ICD registered with OpenGL.
Only main Card on your system is refered as OpenGL display (even if voodoo1/2 shortcuts ICD with its own driver).
So multiple monitor is only for multiple output on a video card.
(Look at matrox or NVidia...)
There is a lot of thread related on it periodicaly.

Another point about multiple view:
On NVidia card (may be not all), when using nview and to monitor, hardware acceleration is not share.
You can notice slow down on first monitor, and not on the second.
So a Nvidia member could tell you more about that.