Swift PKCanvasに四角を追加する

2021年9月14日

参考
stack overflow「Convert UIBezierPath to PKStrokePath swift」

Example

func strokeRectangle() {
    let pointArrays = [
        [CGPoint(x: 100, y: 100), CGPoint(x: 200, y: 100), CGPoint(x: 200, y: 200), CGPoint(x: 100, y: 200), CGPoint(x: 100, y: 100)],
    ]
    let ink = PKInk(.pen, color: .black)
    var strokes: [PKStroke] = []

    for points in pointArrays where points.count > 1 {
        let strokePoints = points.enumerated().map { index, point in
            PKStrokePoint(location: point, timeOffset: 0.1 * TimeInterval(index), size: CGSize(width: 3, height: 3), opacity: 2, force: 1, azimuth: 0, altitude: 0)
        }

        var startStrokePoint = strokePoints.first!

        for strokePoint in strokePoints {
            let path = PKStrokePath(controlPoints: [startStrokePoint, strokePoint], creationDate: Date())
            strokes.append(PKStroke(ink: ink, path: path))
            startStrokePoint = strokePoint
        }
    }
    self.pkcanvasview!.drawing.strokes.append(contentsOf: strokes)
}