View Full Version : Quad Buffer Stereo on HMD

10-05-2003, 11:51 PM
I am using openGL to display stereo images on HMD. HMD has 1 VGA connector and no sync plug. I,

-Enabled Quad Buffer Stereo on ATIFireGL2
-Enabled 3D Support on i-glasses SVGA3D HMD
-Used glDrawBuffer(GL_BACK_RIGHT) and glDrawBuffer(GL_BACK_LEFT) to render stereo

Both opengl and i-glasses use frame sequential stereo. So, different images r shown on each hmd display. But after 5 seconds, the images swap, i.e. left image goes to right display and vice versa. The problem recurs with WildCat4.

Any ideas what the problem could be?

10-25-2003, 09:37 AM
The problem is typical of stereo viewing devices which don't use a stereo sync signal. In this case the graphics board left/right sequential display output is free-running, but the HMD is missing sync every so often.

Note that with graphics controllers which have hardware-based stereo display support, the alternation of left/right fields is guaranteed to occur on every VSync interval. So the problem then would be entirely with the viewing device.