gtaze tracking library?

Hi guys. I’m looking for a gaze tracking library which will be usable with Panda3D.
I just need to track the eyeball rotations to guess where the user is looking on the screen.
It’s useful for having NPCs react to when you look at them, navigating menus and doing advanced DOF, among other things.

Some of these libraries support ordinary webcams of your laptops or cameras on top of the monitor but I’ll probably go with IR cameras attached to a glasses frame with IR red and IR LEDs. I already built one and the position/rotation tracking works fine. There are ready solution but way above my budget. This project is still a research and not for an end product (game or other simulation) so I see no point in wasting money on proprietary eyewear with their proprietary SDKs.

Therefore from the gaze tracking library I only need it to receive a stream of grayscale frames and calculate eye rotation and provide those numbers to me each frame, nothing more.

Since I’m going to use it with this engine a library using Python would be great, but C/C++ would work too.

Thank you all.