picture-in-picture

[vr_boyko]

despite figuring out the texture/crasing bug,
I have not been able to use picture-in-picture with an HMD (head mounted display) in stereo correctly.

While the main view is split correctly and shows a slighlty different image for each eye, the subwindown only shows up on one eye when stereo vision is on.

can a non-main window be forced to show up in stereo vision, or do I need to hack my way around that and introduce two windows and manually calculate the eye-to-eye distance between the two sub-views?