ios – 为sceneKit视图添加了按钮,但它有一个滞后

我在sceneKit视图中添加了一个自定义按钮.触摸时,它会播放动画,表示已单击.我面临的问题是用户触摸和动画开始之间的延迟.我的场景有28.1K三角形和84.4K顶点.是那么多,还是我需要以不同的方式实现按钮.场景渲染为60fps.我通过sceneView.addSubview添加了按钮：谢谢你的回答

viewDidLoad(){
     // relevant code
        starButton = UIButton(type: UIButtonType.Custom)
        starButton.frame = CGRectMake(100,100,50,50)
        starButton.setimage(UIImage(named: "yellowstar.png"),forState: UIControlState.normal)
        sceneView.addSubview(starButton)
        starButton.addTarget(self,action: "starButtonClicked",forControlEvents: UIControlEvents.TouchUpInside)
        starButton.adjustsImageWhenHighlighted = false
        }



    func starButtonClicked(){
            animateScaleDown()

        }

    func animateScaleDown(){

        UIView.animateWithDuration(0.1,animations: {
            self.starButton.transform = CGAffineTransformMakeScale(0.8,0.8)

            },completion: { _ in
                self.wait()
        })

    }

    func wait(){
        UIView.animateWithDuration(0.2,animations: {},completion: { _ in
            UIView.animateWithDuration(0.2,animations: {
                self.starButton.transform = CGAffineTransformMakeScale(1,1)

            })
        })
    }

starButton.addTarget(self,forControlEvents: UIControlEvents.TouchUpInside)