Create a func to undo a UIBezierPath drawing - swift

Question

My code below is in 2 separate classes. From class gooGoo I want to be able to call func change to be used as a undo button to what was drawn on the uiview. Most of the uiview properties are subclassed into classDrawingView.
I have not seen any prior questions on this using a UIBezierPath.
class gooGoo : UIViewController{
var myLayer = CALayer()
var path = UIBezierPath()
var startPoint = CGPoint()
var touchPoint = CGPoint()
var drawPlace = DrawingView()
func Change(){
drawPlace.drawColor = UIColor.black
}
}
class DrawingView: UIView {
var drawColor = UIColor.black
var lineWidth: CGFloat = 5
private var lastPoint: CGPoint!
private var bezierPath: UIBezierPath!
private var pointCounter: Int = 0
private let pointLimit: Int = 128
private var preRenderImage: UIImage!
// MARK: - Initialization
override init(frame: CGRect) {
super.init(frame: frame)
initBezierPath()
}
func takeSnapshotOfView(view:UIView) -> UIImage? {
UIGraphicsBeginImageContext(CGSize(width: view.frame.size.width, height: view.frame.size.height))
view.drawHierarchy(in: CGRect(x: 0, y: 0.0, width: view.frame.size.width, height: view.frame.size.height), afterScreenUpdates: true)
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
initBezierPath()
}
func initBezierPath() {
bezierPath = UIBezierPath()
bezierPath.lineCapStyle = CGLineCap.round
bezierPath.lineJoinStyle = CGLineJoin.round
}
// MARK: - Touch handling
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch: AnyObject? = touches.first
lastPoint = touch!.location(in: self)
pointCounter = 0
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let touch: AnyObject? = touches.first
let newPoint = touch!.location(in: self)
bezierPath.move(to: lastPoint)
bezierPath.addLine(to: newPoint)
lastPoint = newPoint
pointCounter += 1
if pointCounter == pointLimit {
pointCounter = 0
renderToImage()
setNeedsDisplay()
bezierPath.removeAllPoints()
}
else {
setNeedsDisplay()
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
pointCounter = 0
renderToImage()
setNeedsDisplay()
bezierPath.removeAllPoints()
}
override func touchesCancelled(_ touches: Set<UITouch>?, with event: UIEvent?) {
touchesEnded(touches!, with: event)
}
// MARK: - Pre render
func renderToImage() {
UIGraphicsBeginImageContextWithOptions(self.bounds.size, false, 0.0)
if preRenderImage != nil {
preRenderImage.draw(in: self.bounds)
}
bezierPath.lineWidth = lineWidth
drawColor.setFill()
drawColor.setStroke()
bezierPath.stroke()
preRenderImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
}
// MARK: - Render
override func draw(_ rect: CGRect) {
super.draw(rect)
if preRenderImage != nil {
preRenderImage.draw(in: self.bounds)
}
bezierPath.lineWidth = lineWidth
drawColor.setFill()
drawColor.setStroke()
bezierPath.stroke()
}
// MARK: - Clearing
func clear() {
preRenderImage = nil
bezierPath.removeAllPoints()
setNeedsDisplay()
}
// MARK: - Other
func hasLines() -> Bool {
return preRenderImage != nil || !bezierPath.isEmpty
}
}