我有一个尝试转换为Swift 3的Gradient类，但是出现以下错误

迅速无法使用“ CGPointMake”

对于

func configureGradientView() {

    let color1 = topColor ?? self.tintColor as UIColor
    let color2 = bottomColor ?? UIColor.black as UIColor
    let colors: Array <AnyObject> = [ color1.cgColor, color2.cgColor ]
    let layer = self.layer as! CAGradientLayer

    layer.colors = colors
    layer.startPoint = CGPointMake(startX, startY)
    layer.endPoint = CGPointMake(endX, endY)
}

任何人都可以帮我解决我可以代替的东西 CGPointMake

这是全班；

@IBDesignable public class XGradientView: UIView {

@IBInspectable public var topColor: UIColor? {
    didSet {
        configureGradientView()
    }
}
@IBInspectable public var bottomColor: UIColor? {
    didSet {
        configureGradientView()
    }
}
@IBInspectable var startX: CGFloat = 0.0 {
    didSet{
        configureGradientView()
    }
}
@IBInspectable var startY: CGFloat = 1.0 {
    didSet{
        configureGradientView()
    }
}
@IBInspectable var endX: CGFloat = 0.0 {
    didSet{
        configureGradientView()
    }
}
@IBInspectable var endY: CGFloat = 0.0 {
    didSet{
        configureGradientView()
    }
}

public class func layeredClass() -> AnyClass {
    return CAGradientLayer.self
}

public required init(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)!
    configureGradientView()
}

override init(frame: CGRect) {
    super.init(frame: frame)
    configureGradientView()
}

public override func tintColorDidChange() {
    super.tintColorDidChange()
    configureGradientView()
}

func configureGradientView() {

    let color1 = topColor ?? self.tintColor as UIColor
    let color2 = bottomColor ?? UIColor.black as UIColor
    let colors: Array <AnyObject> = [ color1.cgColor, color2.cgColor ]
    let layer = self.layer as! CAGradientLayer

    layer.colors = colors
    layer.startPoint = CGPointMake(startX, startY)
    layer.endPoint = CGPointMake(endX, endY)
}
}