 extension BezierCurve {
     
     // MARK: -
-    
-    var threeD: Bool {
-        return BKPoint.dimensions == 3
-    }
     
     private var dpoints: [[BKPoint]] {
         var ret: [[BKPoint]] = []

            let q = d.length
            return BKPoint( x: -d.y/q, y: d.x/q )
        }
        func normal3(_ t: BKFloat) -> BKPoint {
            let r1 = self.derivative(t).normalize()
            let r2 = self.derivative(t+0.01).normalize()
            // cross product

            n[1] = R10 * r1[0] + R11 * r1[1] + R12 * r1[2]
            n[2] = R20 * r1[0] + R21 * r1[1] + R22 * r1[2]
            return n
        }*/
        return /*(BKPoint.dimensions == 3) ? normal3(t) : */ normal2(t)
    }
    
    // MARK: -
