图像渲染迅速

Question

我正在UIView上渲染一条线。问题是，当我放大视图时，它会变得模糊。我要在放大时保持清晰度。通过在后台渲染图像是否可以实现？如果是，那怎么办？我被困在这一部分。[

下面是绘制线条的代码：

 override  func draw(_ rect: CGRect)
    {
        let shape = CAShapeLayer()
        self.layer.addSublayer(shape)
        shape.fillColor = UIColor.black.cgColor
        shape.strokeColor = UIColor.white.cgColor
        let path = CGMutablePath()
        for stroke in strokePoints
        {
            //print(stroke.startPoint,stroke.endPoint)
            path.move(to: stroke.startPoint)
            path.addLine(to: stroke.endPoint)
        }
        shape.path = path
    }