how to set up multiple cameras in a scene rendering to multiple displays

Unity Engine
1

Hi,

I’m working in an application for immersive user experience.
I would like to have a scene in unity with multiple cameras (4) and send the render of each camera to a different display.
I’m thinking in using an ATI Radeon™ HD 5870 Eyefinity graphics card that allows to have multiple outputs.

It is possible to make this configuration in unity?
I have search in other threads in the forum and documentation but I didn´t find an answer.

Thanks!

Pedro

2

Would creating an application with the pixel width of these 4 monitors do it for you? Are they having the same resolution these monitors?

In thats case just setting up a giant window with 4 cameras with modified viewport rects would do it I guess. Not sure about the performance of such a beast though.

3

To get a unity app running fullscreen over multiple monitors, you need to do the following:

  • Build your application with player settings: Default Screen Width set to (totalScreenWidth - 1), Default Screen Height set to (totalScreenHeight - 1) and Display Resolution Dialog to disabled. So in your case with 4 1920x1080 outputs, you would build with Default Screen Width set to 7679 and Default Screen Height to 1079. The -1 is very important, or you’ll get all sorts of line and pixel artifacts in the output.
  • Start the application without window decoration and force its window resolution to the screen resolution (so that is without the -1). We use the Actual Window Manager (60 day free trial to see if you like it) application to do this for us, but I’m sure there are other ways to get rid of the decoration.

We have used this approach successfully with a high-end (6-output) ATI card, so i’m pretty sure it should work for you as well. It is better to have a single graphics card with 4 outputs, instead of 2 cards with 2 outputs. It isn’t possible to have Unity utilize multiple graphics cards, so with multiple GPU’s only one will do all the work.

If you get it running with my pointers, your app is now simply a single stretched 7680x1080 output equally spread over the 4 monitors, so if you need 4 separate camera’s (for something like a CAVE setup), you can just use 4 cameras with adjusted viewports. If you need overlap areas (in case of a straight tiled display with projectors), you will need to do some additional math to the projection matrices of each camera.

4

thanks for your answer, I don´t have the hardware yet, but It helps to be sure that Unity could work with these graphic cards.

5

@tomvds - Have you tried this to remove the window border? Resume - Start Bootstrap Theme

6

No, I haven’t tried that, but will do right away. Thanks for the link :).

Edit: yes, that works well. So no more need for actual windows manager then. Thanks again.

7

Tomvds - Were you able to get this to work? We have an application where we would like to span a Unity app across two monitors, but rendering one camera to monitor 1, second camera to monitor 2.

8

You get this working? It would be cool to see a walkthrough/tutorial on this exact subject.