# Enter a zone -> push a first-person camera onto that player.
OnEnter(Agent : agent) : void =
    DriverCamera.AddTo(Agent)      # gameplay_camera_first_person_device
    HornInput.Register(Agent)      # input_trigger_device

OnExit(Agent : agent) : void =
    DriverCamera.RemoveFrom(Agent)
    HornInput.Unregister(Agent)