Once you create a context with stereo draw (via the pixel format on context creation)…
The GL_BACK_LEFT and GL_BACK_RIGHT are two completely different buffers correct?
When you set glDrawBuffer(GL_BACK) and draw, does it renders the same image to both the left and right buffers at the same time?
What happens when you set glReadBuffer(GL_BACK) and do a read operation? (glReadPixels, glCopyTexImage, etc)? Is either the left or right buffer just choosen?
If you draw the left eye (into GL_BACK_LEFT), then draw the right eye (into GL_BACK_RIGHT)… do you need to swap immediately or can you draw into the back (GL_BACK) to add an overlay effect to both buffers before you swap?
Well you need a quadro card for a quad buffered pixel format.
The GL_BACK_LEFT and GL_BACK_RIGHT are two completely different buffers correct?
Yes.
What happens when you set glReadBuffer(GL_BACK) and do a read operation? (glReadPixels, glCopyTexImage, etc)? Is either the left or right buffer just choosen?
Back left.
If you draw the left eye (into GL_BACK_LEFT), then draw the right eye (into GL_BACK_RIGHT)… do you need to swap immediately or can you draw into the back (GL_BACK) to add an overlay effect to both buffers before you swap?
you can draw whatever you want into the buffers, but they share a single depth buffer. So normally how it works is, you render the left image, clear the depth buffer then render into the right buffer.
GL_BACK: Only the back left and back right color buffers are written. If there is no back right color buffer, only the back left color buffer is written.
Which matches what I’ve observed on NVidia cards at least.