Swift SpriteKit游戏杆运动溢出

Question

所以基本上，我有sprite kit游戏杆实现。一切正常，除非涉及顶部和底部。基本上，当使用操纵杆绕拐角移动时，它会像在正方形中一样溢出。我知道问题出在我的 moveJoystick（）函数的最后else语句位置操作中，但无法解决。这是我的下课：

    class LiveControllerJoystick: SKNode {

        var joyStick = SKShapeNode()
        var stick = SKShapeNode()
        var joyStickPath: UIBezierPath!
        var maxRange : CGFloat!
        var baseRadius : CGFloat!
        let xValue : CGFloat = 0
        let yValue : CGFloat = 0
        var blockedX: Bool!
        var blockedY: Bool!

        var joyStickAction : ((_ x: CGFloat, _ y: CGFloat) -> ())?

        init(frame: CGRect) {
            // Dynamic Coordinates for SKView
            maxRange = frame.size.width / 3
            baseRadius = frame.size.width / 3
            let joyStickRect = CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height)
            joyStickPath = UIBezierPath(ovalIn: joyStickRect)

            joyStick = SKShapeNode(path: joyStickPath.cgPath,centered: true)
            joyStick.strokeColor = UIColor.clear
            let stickRect = CGRect(x: 0, y: 0, width: frame.size.height / 3, height: frame.size.height / 3)
            let stickPath = UIBezierPath(ovalIn: stickRect)
            stick = SKShapeNode(path: stickPath.cgPath,centered: true)

            stick.strokeColor = UIColor.clear
            stick.lineWidth = 4

            super.init()
            stick.fillColor = hexStringToUIColor(hex: "#2D2D2D")
            joyStick.fillColor = hexStringToUIColor(hex: "#830B2C")
            addChild(joyStick)
            addChild(stick)


        }

        required init?(coder aDecoder: NSCoder) {
            fatalError("init(coder:) has not been implemented")
        }

        // MOve Joystick Up,Down,Left,Right
        func moveJoystick(touch: UITouch){
            let p = touch.location(in: self)
            let radius = min(baseRadius,sqrt(pow(p.y, 2) + pow(p.x, 2)))
            var angle = atan2(p.y, p.x)
            angle = (angle * 2 / CGFloat.pi).rounded() * (CGFloat.pi / 2)
            if((blockedY == true && blockedX == true) || (blockedX == true && blockedY == true)){
                stick.position = CGPoint(x: 0, y: 0)
            }
            else if(blockedY == true){
                 stick.position = CGPoint(x: cos(angle) * radius, y: 0)
            }
            else if(blockedX == true){
                stick.position = CGPoint(x: 0, y: sin(angle) * radius)
            }
            else{
                let x = p.x.clamped(-maxRange, maxRange)
                let y = p.y.clamped(-maxRange, maxRange)
                stick.position = CGPoint(x: x, y: y)
            }
            let xValue = cos(angle) * radius
            let yValue = sin(angle) * radius

            if let joyStickAction = joyStickAction {
                joyStickAction(xValue,yValue)
            }
        }

        func hexStringToUIColor (hex:String) -> UIColor {
            var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()

            if (cString.hasPrefix("#")) {
                cString.remove(at: cString.startIndex)
            }

            if ((cString.count) != 6) {
                return UIColor.gray
            }

            var rgbValue:UInt64 = 0
            Scanner(string: cString).scanHexInt64(&rgbValue)

            return UIColor(
                red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
                green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
                blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
                alpha: CGFloat(1.0)
            )
        }
    }
// Return min max value
extension CGFloat {

    func clamped(_ v1: CGFloat,_ v2: CGFloat) -> CGFloat {
        let min = v1 < v2 ? v1 : v2
        let max = v1 > v2 ? v1 : v2

        return self < min ? min : (self > max ? max : self)
    }

}

任何帮助或提示，我们将不胜感激。预先感谢。