apart from the endless tweaking and headaches, it worked. The only problem is that games had to render one frame for each eye so framerate dropped by half.

LCD Shutter-glasses have been around at least since the early nineties. And you’re right about it having to be frame-locked with the display – no amount of coding in software land will get you desirable results.

IIRC, some older commercial cards (Voodoo2 I think) actually came *with* glasses like this, but they never really caught on. They had a dedicated port (1/8 jack) on the card to handle all this.

A superior hack would be to somehow snoop the VGA signals coming from a more recent card (like on the port itself) in order to drive the shutters on just about any hardware imaginable; just use a pic to listen for vsync and bob’s your uncle. Then it’s just a matter of providing a switch to flip which shutter (L or R) is dominant since there would be no way to know which frame (L or R) is being rendered.

the renderer would have to be frame-locked with the display (unlike most games that pump out as many frames as they can), not to mention render to a different camera every other frame. you would need some way to accurately synchronize the display frame switching with the glasses. serial/usb might be too slow/have too much latency, so maybe tap into the monitor’s refresh signal?

Also, english isn’t my first language, but isn’t “an SGI” wrong…?