图表路径动画

我试图实现改变图表数据的动画。我使用以下代码:

if let chartLayer = chartLayers[chartName], chartLayer.superlayer != nil {
                let animation = CABasicAnimation.init(keyPath: "path")

                animation.fromValue = chartLayer.path
                animation.toValue = path.cgPath
                animation.duration = 0.2

                animation.delegate = self
                chartLayer.path = path.cgPath
                self.isAnimated = true
                chartLayer.add(animation, forKey: "path")
            } else {
                let chartLayer = CAShapeLayer()
                chartLayer.lineWidth = 2.0
                chartLayer.fillColor = UIColor.clear.cgColor
                chartLayer.strokeColor = UIColor.init(hexFromString: chartData.colors[yData.key] ?? "").cgColor
                chartLayer.path = path.cgPath
                layer.addSublayer(chartLayer)
                chartLayers[chartName] = chartLayer
            }

现在在右边修改数据看起来不错,但是在左边看起来很奇怪。有人能给我指点我做错了什么吗?

更新:我希望左边的更改数据看起来与右边的相同(我的意思是平滑地更改比例并添加更多的行)