Gradually decrease animation speed on a SCNNode? [IOS]

Question

As I swipe on the screen I want a SCNNode object to rotate while the speed is decreasing. When the speed is 0 the animation should stop. Here is my code:

ViewDidLoad:

    sceneView.delegate = self

    let scene = SCNScene(named: "art.scnassets/Cube.dae")!
    self.cubeNode = scene.rootNode.childNode(withName: "Cube", recursively: true)
    self.cubeNode?.position = SCNVector3Make(0, 0, -1)
    sceneView.scene = scene

    let swipeRight = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes(gesture:)))
    swipeRight.direction = UISwipeGestureRecognizerDirection.right
    self.view.addGestureRecognizer(swipeRight)

    let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes(gesture:)))
    swipeLeft.direction = UISwipeGestureRecognizerDirection.left
    self.view.addGestureRecognizer(swipeLeft)

The handleSwipes function:

@objc func handleSwipes(gesture: UIGestureRecognizer) {

    if let swipeGesture = gesture as? UISwipeGestureRecognizer {
        switch swipeGesture.direction {
        case UISwipeGestureRecognizerDirection.right:
            animateSpin(direction: .right)
        case UISwipeGestureRecognizerDirection.left:
            animateSpin(direction: .left)
        default:
            break
        }
    }
}

And the animateSpin function:

func animateSpin(direction: SwipeDirection) {
    let spin = CABasicAnimation(keyPath: "rotation")
    spin.fromValue = NSValue.init(scnVector4: SCNVector4(0, 0, 0, 0))
    switch direction {
    case .left:
        spin.toValue = NSValue.init(scnVector4: SCNVector4(x: 0, y:-1, z:0, w: 2 * .pi))
    case .right:
        spin.toValue = NSValue.init(scnVector4: SCNVector4(x: 0, y:1, z:0, w: 2 * .pi))
    }
    spin.speed = 1
    spin.repeatCount = 20
    self.cubeNode!.addAnimation(spin, forKey: "spin around")
}

I also have an enum for the directions:

enum SwipeDirection {
    case right
    case left
}

Would really appreciate any suggestions on how to do this. Is there a way to run some code after each animation repeat?

[SOLVED]

Gradually decrease animation speed on a SCNNode? [IOS]

0 Answers0