code: function(point) {
                  var P = point.elements || point;
                  var A = this.anchor.elements, N = this.normal.elements;
                  var dot = (A[0] - P[0]) * N[0] + (A[1] - P[1]) * N[1] + (A[2] - (P[2] || 0)) * N[2];
                  return vector.create([P[0] + N[0] * dot, P[1] + N[1] * dot, (P[2] || 0) + N[2] * dot]);
                }
docs: Returns the point in the plane closest to the given point