Stereo control signal?

[StefanG]

Does anyone know how to control the stereo signal left/right output on nVidia cards? (It's present on a pin in the VGA connector, and some cards, like the ASUS Deluxe versions, have it routed to a separate 3.5 mm plug.)

If left unattended, the signal flips from left to right on each vsync, but I want to be able to tell my stereo glasses whether I am rendering a left or right view.

The workaround I can think of is to feed the left/right signal into the parallel port and let that control the rendering, but it would be nice to know how to set the signal.

Right now my stereo application asks the user to press a key until a square is seen only by the left eye, and then I keep track of frames. It's a hassle, because rendering pauses during window resize and drag, and then I have to use a timer to infer how many frames were dropped. This also requires a good estimate of the refresh rate. I can probably manage to get it reasonably stable, but it's a kludge.

Any pointer to an alternative is appreciated. (Any nice Nvidia people around here?)


[This message has been edited by StefanG (edited 11-21-2002).]

[StefanG]

Sigh. I guess I am the only one in the whole wide world crazy enough to want this. Zero replies... :-[