Unity Multi-display the second camera show nothing, is black

0 votes
asked Sep 26 by Adam Wu (12 points)

Sorry for my poor English.

I want to render different things using different cameras to different monitors. Main Camera is Stereo Camera to ZSpace display(VR views). other cameras is 

The Unity Setting likes this:

1) Camera that is you VR camera (eyes): Target Display = Display 1 > Target Eye = BOTH

2) Second camera (for desktop monitor): Target Display = Display 2 > Target Eye = None (Main Display)

It works well in normal computer (no vr effects), like this:(right is main camera)

But it works wrong when run in ZSpace. Maincamera is ok(the right one), other cameras show nothing(left one):

How to solve this problem, or can i use other ways to have this effect?  VERY urgent

commented Sep 26 by AlexShorey (40 points)
Hi Adam,

Sorry to hear that you're having troubles with this. I can't recall anybody here attempting this particular display configuration. I'm asking around to see if anybody here has had some prior success in this. What version of Unity3D are you using? Are you using version 4 or 5 of the plugin? Considering this is a very urgent issue, sharing with us a sample project that replicates the problem would be the most expedient way to reach a solution.

In any case, I'm looking into this.
Alex S.
commented Sep 26 by Adam Wu (12 points)
i am using Unity5.6.3f1 and SDK zCore5.
How to send the sample code to u?
commented Sep 26 by AlexShorey (40 points)
edited Sep 27 by AlexShorey
Thank you for the details, that will be helpful. Whatever means you have to share the sample will be acceptable, Google Drive, Dropbox, etc.  Or you can email it to me directly if its small enough to fit in an attachment. ######@######.com
commented Sep 27 by AlexShorey (40 points)
Hi Adam, I received your sample project demonstrating the issue you're having. I did some testing and looked around for answers, but didn't come up with much. I encountered the same problem when constructing a project without the zSpace plugin. It seems that Unity 5.6 and up can't render a stereo display and a non-stereo display at the same time with the current built in VR support.

The issue is affecting Steam VR developers as well.
https://forum.unity.com/threads/steam-open-vr-and-main-cameras-no-longer-render-simultaneously.453212/
commented Sep 27 by Adam Wu (12 points)
Thanks for ur reply.
I have searched for this issue, and found the bug in unity bugtracker .
https://issuetracker.unity3d.com/issues/stereo-display-vr-does-not-render-on-multiple-displays

It should be a unity bug.

Thanks very much.
commented Sep 27 by AlexShorey (40 points)
Thanks for sharing the tracker. I'll up-vote that issue since I'd really like to see it working as well.

1 Answer

0 votes
answered Oct 2 by AlexShorey (40 points)

Per the comment thread, this seems to be a Unity feature that currently isn't working as expected.

https://issuetracker.unity3d.com/issues/stereo-display-vr-does-not-render-on-multiple-displays

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