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How to work with VectorArithmetic and Accelerate

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Hey guys, I am trying to animate curves in SwiftUI, I have a BezierShape defined like this:

struct BezierShape: Shape {

    var startPoint: CGPoint
    var curves: [Curve]

    init(startPoint: CGPoint, curves: [Curve]) {
        self.startPoint = startPoint
        self.curves = curves

    func path(in rect: CGRect) -> Path {
        var path = Path()
        let width = rect.size.width
        let height = rect.size.height

        // Move the the start point
        let startPoint = CGPoint(x: startPoint.x*width, y: startPoint.y*height)
        path.move(to: startPoint)

        // Draw the curves
        for c in curves {
            path.addCurve(to: CGPoint(x: c.destination.x*width, y: c.destination.y*height),
                          control1: CGPoint(x: c.control1.x*width, y: c.control1.y*height),
                          control2: CGPoint(x: c.control2.x*width, y: c.control2.y*height))

        return path

struct Curve {
    var destination: CGPoint
    var control1: CGPoint
    var control2: CGPoint

To animate the bezier shape, I am changing the values passed as parameters to this struct, but since I didn't include an animatableData property, SwiftUI doesn't know how to animate these values. I know that to create this property I must use values that conform to VectorArithmetic, so for the start point property I can use its x- and y-values, as these conform to VectorArithmetic. But the array of Curve values doesn't. And I don't know how I can make it conform to VectorArithmetic. If someone could help me with this that would be greatly appreciated!

P.S. I've found this article from Swift with Majid explaining how to make an array conform to VectorArithmetic with the use of Accelerate, this gave me a better understanding of the situation and how I could approach it, but I don't know Accelerate nor VectorArithmetic enough to be able to find a solution with this article.


Take a look at https://github.com/hyperjeff/Accelerate-in-Swift. Several examples of using Accelerate, some of which may help you.


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