ios - 从一点到另一点的弯曲箭头

Question

我需要绘制一个从一点到另一点的弯曲箭头。我确实设法从下面的扩展中得到了一个直箭头。

extension UIBezierPath {

static func arrow(from start: CGPoint, to end: CGPoint, tailWidth: CGFloat, headWidth: CGFloat, headLength: CGFloat) -> UIBezierPath {
    let length = hypot(end.x - start.x, end.y - start.y)
    let tailLength = length - headLength

    func p(_ x: CGFloat, _ y: CGFloat) -> CGPoint { return CGPoint(x: x, y: y) }
    let points: [CGPoint] = [
        p(0, tailWidth / 2),
        p(tailLength, tailWidth / 2),
        p(tailLength, headWidth / 2),
        p(length, 0),
        p(tailLength, -headWidth / 2),
        p(tailLength, -tailWidth / 2),
        p(0, -tailWidth / 2)
    ]

    let cosine = (end.x - start.x) / length
    let sine = (end.y - start.y) / length
    let transform = CGAffineTransform(a: cosine, b: sine, c: -sine, d: cosine, tx: start.x, ty: start.y)

    let path = CGMutablePath()
    path.addLines(between: points, transform: transform)


    path.closeSubpath()

    return self.init(cgPath: path)
}}

我目前从上面的代码中得到了什么。

我需要什么。

Answer 1

使用addArc方法创建曲线(而不是直线):-

path.addArc(tangent1End: start, tangent2End: end, radius: 30)

或

path.addArc(center: CGPoint(x: 100, y: 100), radius: 30, startAngle: 270, endAngle: 360, clockwise: true, transform: transform)