Point-of-gaze of a user looking at a display is estimated, taking into account rotation of the users head or rotation of the display. An image of an eye of the user is captured. The image is processed to determine coordinates in the image of defined eye features, sufficient to determine the eyes optical axis. At least one angle is determined, the at least one angle proportional to an angle between (i) a line coincident with an edge of the display and (ii) an intersection of the sagittal plane of the users head with a plane of the display. An intersection of the eyes line-of-sight with the plane of the display is estimated using the eyes optical axis, and using the at least one angle to account for rotation of the users head or the display.