Thanks. Unfortunately, the shader method doesn't work well for me because I use the NVIDIA 3D Vision system to get stereoscopic viewing (The NVIDIA software automatically creates a left eye image and right eye image from the 3D information the Acknex engine sends to the graphics card . If I could force flip the left and right eye images it would work fine, but as far as I know, the NVIDIA drivers don't have any ability to do that. My only workaround is to wear the glasses upside down which isn't very acceptable.