CircleToRectangle-Step-4.swift

private var rectanglePath: CGPath {
  let width = frame.size.width
  let height = frame.size.height
  let myPath = UIBezierPath()
  myPath.lineCapStyle = CGLineCap.butt
  myPath.lineJoinStyle = CGLineJoin.miter
  
  myPath.move(to: CGPoint.zero)
  myPath.addQuadCurve(to: CGPoint(x:width,y:0), controlPoint:CGPoint(x:width/2.0,y:0))
  myPath.addQuadCurve(to: CGPoint(x:width,y:height), controlPoint:CGPoint(x:width,y:height/2.0))
  myPath.addQuadCurve(to: CGPoint(x:0,y:frame.size.height), controlPoint:CGPoint(x:width/2.0,y:height))
  myPath.addQuadCurve(to: CGPoint.zero, controlPoint:CGPoint(x:0,y:height/2.0))

  myPath.close()
  return myPath.cgPath
}