Vizard uses the
glColorMask command to render anaglyphic stereo. Basically, the code works like this:
Code:
glColorMask(GL_TRUE, GL_FALSE, GL_FALSE, GL_TRUE);
RenderLeftEye();
glColorMask(GL_FALSE, GL_TRUE, GL_TRUE, GL_TRUE);
RenderRightEye();
That's pretty much it. If you need more advanced control over the color filtering, then you will have to use a post-process shader. Let me know if you are interested in this and I can provide you some code.