Method and system for determining a current gaze direction

Method for determining a current gaze direction of a user in relation to a threedimensional ("3D") scene (10), which 3D scene (10) is sampled by a rendering function to produce a two-dimensional ("2D") projection image of the 3D scene (10), which sampling is performed based on a virtual camera (20) in turn being associated with a virtual camera position and virtual camera direction in the 3D scene (10), wherein the method comprises the steps:determining, by a gaze direction detection means (42), a first gaze direction of the user at a first gaze time point (TG1), which first gaze direction is related to said 3D scene (10); determining a virtual camera (20) 3D transformation, which 3D transformation represents a change of a virtual camera (20) position and/or virtual camera (20) direction between the first gaze time point (TG1) and a second sampling time point (TR2), where the second sampling time point (TR2) is later than the first gaze time point (TG1); anddetermining the said current gaze direction as a modified gaze direction, in turn calculated based on the first gaze direction, and further calculated based on an inverse of said virtual camera (20) 3D transformation.The invention also relates to a system and to a computer software function.