combo.swift

// 控制連擊動畫
    func AnimateAlpha(comboNumber : Int) {
        self.combo.alpha = 1
        if comboNumber > 0{
            combo.text = String(comboNumber)+" COMBO"
        }
        UIView.animate(withDuration: 0.7, delay: 0, animations: {
            self.combo.alpha -= 1
            self.combo.transform = CGAffineTransform.identity
                .translatedBy(x: -100, y: 0)
                .rotated(by:CGFloat(Double.pi/4))
                .scaledBy(x: 2, y: 2)
        }, completion: { _ in
            self.combo.transform = CGAffineTransform.identity
        })
        
    }