signature HULL =
    sig

	type faceData
	
	structure Geometry : GEOMETRY
	structure Complex : 
	    SIMPLICIAL_COMPLEX where type Vertex.point = Geometry.Point.t

	val hull : 
	    Complex.Vertex.point list -> faceData Complex.complex

	(* Used for statistics *)
	val makePlaneCount : int ref
	val lineSideCount : int ref
	val searchCount : int ref
	val addCount : int ref
	val remCount : int ref
	val clearCount : unit -> unit

    end