Track3D &get_track(Track &) const;
Track3D *pick_track(float, float, float) const;
void add_vehicle(Vehicle3D &);
void remove_vehicle(Vehicle3D &);
Track3D &get_track(Track &) const;
Track3D *pick_track(float, float, float) const;
void add_vehicle(Vehicle3D &);
void remove_vehicle(Vehicle3D &);