Question

当我在屏幕上滑动时，我希望SCNNode对象在速度降低时旋转。当速度为0时，动画应该停止。这是我的代码：

viewDidLoad中：

    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)

handleSwipes函数：

@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
        }
    }
}

和animateSpin功能：

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")
}

我也有一个方向的枚举：

enum SwipeDirection {
    case right
    case left
}

非常感谢有关如何执行此操作的任何建议。有没有办法在每次动画重复后运行一些代码？

[解决]

逐渐降低SCNNode上的动画速度？ [IOS]

0 个答案: