View Full Version : 4 GraphicsCards, 4 Monitor, 1Game

05-26-2002, 11:30 PM
Hi, everyone
It could sounds strage ..
But how can i draw one game screen to 4 graphics cards and each connected each monitor in windows application
i have not any idea that proplem
any hints?

05-26-2002, 11:59 PM
Just a wild idea. You could make the rendering system like a slave thread, one thread for each graphics board, or something similar. Then make a server thread that sends the game related data, like player position, movements, actions like spawning a particle system, to each rendering thread.

05-27-2002, 08:07 AM
Are you talking about 4 cards in one machine or ....
cause otehrwise I think you wont have GL acceleration at all, unless there is something new here you should tell me.

The server/client method will work for 4 machines nicely.

05-27-2002, 06:26 PM
thank you~
i'll take 4cards and 4monitor in one main board
i have no idea about how i can make 4 windows and 4 DC(windows) and 4 RC(opengl)
and combine~
please hint me~!

05-27-2002, 10:21 PM
Unlike DirectX, I don't think it's possible (didn't use to be anyway) to select hardware device in wgl. Every RC will be connected to the 'default' device.

05-27-2002, 11:08 PM
If you're using a PC, where do you think you can find a motherboard with 4 AGP slots?
I guess you don't want to use old PCI cards...Anyway, if you find the solution, let us know.

05-28-2002, 04:43 PM
Originally posted by hq:
Unlike DirectX, I don't think it's possible (didn't use to be anyway) to select hardware device in wgl. Every RC will be connected to the 'default' device.

What if one makes an extended desktop covering all 4 monitors and you just move the window over the the desired (x, y) position or simply create them there.

That will require a single video card with 4 ports and I havent seen one of those.

PS: nvidia is suppose to add support for multiple devices for opengl soon (summer?)


05-28-2002, 11:04 PM
V-man, Typically you want to orient the monitors in a curve, so each need ther own projection. What you are describing is not good for very wide (wraparound) fields of view.

The best way to do this is to have several networked PCs each running the same game with some game information being shared, perhaps with some slave PCs and one system running the game. The game system may have an extra CPU or may have no graphics with only the slaves running graphics. This way you can sustain better performance on graphics cards because each system can drive a graphics card with a dedicated CPU and AGP 4X graphics bus.

You can build you own system like this or go to someone who builds them for you, here is one example. You can stick these in a 19 inch rack and they supply software to help you program it:

05-28-2002, 11:07 PM

Each box is a PC in a thin 19 inch rack mountable chassis. These are not cheap AFAIK, each video you need with a 3D view on it is generally called a "channel", just to help you understand the lingo a bit.

If you want to build your own with a bunch of PCs you may still want help writing graphics software to run transparently over a network there are companies which help you do this, here is one example:
(Only the Pro version has multiple channel support, they call it MultiVis).

These both look like defense oriented companies because immersive training systems has been the primary market for hardware and software for multi-channel wraparound graphics.

[This message has been edited by dorbie (edited 05-29-2002).]