项目中经常使用到圆角或者菱角之类的，最快捷简单的方法就直接找UI切图，少则好说，多则占存储空间。直接用系统自带的绘制圆角的方法，又怕出现离屏渲染，这个时候就考虑使用贝塞尔曲线绘制圆角或者菱角。
以下是绘制圆角的写法(菱角同理)
struct LynnFilletPolygon: Shape {
let a: CGFloat
let b: CGFloat
func path(in rect: CGRect) -> Path {
var path = Path()
path.move(to: CGPoint(x: 0, y: b))
path.addQuadCurve(
to: CGPoint(x: a, y: 0),
control: CGPoint(x: 0, y: 0)
)
path.addLine(to: CGPoint(x: rect.width-a, y: 0))
path.addQuadCurve(
to: CGPoint(x: rect.width, y: b),
control: CGPoint(x: rect.width, y: 0)
)
path.addLine(to: CGPoint(x: rect.width, y: rect.height-b))
path.addQuadCurve(
to: CGPoint(x: rect.width-a, y: rect.height),
control: CGPoint(x: rect.width, y: rect.height)
)
path.addLine(to: CGPoint(x: a, y: rect.height))
path.addQuadCurve(
to: CGPoint(x: 0, y: rect.height-b),
control: CGPoint(x: 0, y: rect.height)
)
path.addLine(to: CGPoint(x: 0, y: b))
return path
}
}
