A system may be controlled by directing at least a portion of a field-of-view of one or more cameras across a screen of a display for the system, using the one or more cameras to track in three dimensions an object moving in a space in front of the screen, and providing input to the system based on the tracking of the object. A system may also be controlled by directing a first portion of a field-of-view of a camera in a first direction, directing a second portion of the field-of-view of the camera in a second direction across a screen of a display for the system, tracking an object moving in front of the screen with the second portion of the field-of-view of the camera, and providing input to the system based on the tracking of the object.