A method for determining if a user's gaze is directed in the direction of a zone of interest in a 3D scene comprises: providing a 3D scene containing a zone of interest; associating a property with the zone of interest; creating a bitmap representing the location of the zone of interest in a projected view of the 3D scene, each pixel of the bitmap to which the zone of interest is projected storing the property of the zone of interest; detecting the direction of the user's gaze; using the bitmap to determine if the detected user's gaze is directed in the direction of the zone of interest.