BreatheApp8.swift

private struct RingShape: Shape {
    var startAngle: Angle
    var endAngle: Angle
    let ringWidth: CGFloat

    var animatableData: Double {
        get {return endAngle.radians}
        set {endAngle = Angle(radians: newValue)}
    }

    func path(in rect: CGRect) -> Path {
          var path = Path()
          let center = CGPoint(x: rect.midX, y: rect.midY)
          let radius = (min(rect.width, rect.height) - ringWidth)/2
         path.addArc(center: center,
                   radius: radius,
                   startAngle: startAngle,
                   endAngle: endAngle, clockwise: false)
         return path.strokedPath(.init(lineWidth: ringWidth, lineCap: CGLineCap.round))
    }
}