1. A method comprising: capturing an image that includes a left eye of a subject and a right eye of the subject; identifying, from the image, a plurality of glints from the left eye and a plurality of glints from the right eye as left glint data and right glint data, respectively; determining, from the image, pupil center information of the left eye and pupil center information of the right eye as left pupil data and right pupil data, respectively; combining the left glint data, left pupil data, right glint data, and right pupil data to determine a gaze location of the subject.