Cycling 74 » Topic: How to preserve a gl context when external monitor is turned off?

How to preserve a gl context when external monitor is turned off?

zlp — Thu, 22 Jul 2010 13:20:02 +0000

I’m wondering if anybody has a solution to a nagging problem: When a Jitter window is running in fullscreen mode on an external monitor or projector, MAX crashes when the monitor is turned off or disconnected. (Or in some cases it seems to exit fullscreen more gracefully, but it needs help to get back to fullscreen when the monitor is restored.)

I understand that the OS is pulling the rug out from under Jitter’s GL context, so perhaps nothing can be done. Nevertheless, I am involved with a lot of jitter-based installations with multiple projectors and inevitably somebody forgets to turn off the max patch before turning off a projector. Disaster ensues.

In the thread below, “MJ” mentions passing each VGA signal through an amp to preserve the gl context when a projector is removed. I assume something similar can be done with an active DVI switch or amp?
“rendering multiple GL views on a Mac Pro 4 x NVIDIA GeForce GT 120″

http://cycling74.com/forums/topic.php?id=23020

Any thoughts?

Re: How to preserve a gl context when external monitor is turned off?

generalh — Thu, 22 Jul 2010 14:38:26 +0000

Hello,
Using a triple head or equivalent should do the trick as long as nobody disconnect the matrox box…Using it permits to turn on and off the video projector or screen without having the GL context to be rebuild…as far as i’ve tested…
HTH
Hubert

Re: How to preserve a gl context when external monitor is turned off?

zlp — Thu, 22 Jul 2010 15:17:19 +0000

Commenting on my own post. I wonder if the “DVI Doctor” would fit the bill. It memorizes the “handshake” info from the projector and repeats that info even if the projector is turned off. So the computer thinks the projector is always on.

http://www.monoprice.com/products/product.asp?c_id=101&cp_id=10110&cs_id=1011003&p_id=3048&seq=1&format=2