Estimating the gaze using pupil and glint xy coordinates

Question

I have managed to track the center x y coordinate and the radius of the pupil using opencv.

Now I want to measure the gaze using it.

If somebody can help me with the theory part of it, probably I will be able to code it.

Any open source program will also do.

Update : I am able to track a glint on the cornea also now. According to my online research the coordinates of the pupil is compared with the glint to estimate the gaze. How do I go about doing that?

Answer 1

Finally got some lead, from SO itself -

https://stackoverflow.com/a/4454006/1458387