Pinch in ARKit

gistfile1.txt

let pinchGesture = UIPinchGestureRecognizer(target: self, action: #selector(didPinch(_:)))
        sceneView.addGestureRecognizer(pinchGesture)

@objc
    func didPinch(_ gesture: UIPinchGestureRecognizer) {
        guard let _ = object else { return }
        var originalScale = object?.scale
 
        switch gesture.state {
        case .began:
            originalScale = object?.scale
            gesture.scale = CGFloat((object?.scale.x)!)
        case .changed:
            guard var newScale = originalScale else { return }
            if gesture.scale < 0.5{ newScale = SCNVector3(x: 0.5, y: 0.5, z: 0.5) }else if gesture.scale > 2{
                newScale = SCNVector3(2, 2, 2)
            }else{
                newScale = SCNVector3(gesture.scale, gesture.scale, gesture.scale)
            }
            object?.scale = newScale
        case .ended:
            guard var newScale = originalScale else { return }
            if gesture.scale < 0.5{ newScale = SCNVector3(x: 0.5, y: 0.5, z: 0.5) }else if gesture.scale > 2{
                newScale = SCNVector3(2, 2, 2)
            }else{
                newScale = SCNVector3(gesture.scale, gesture.scale, gesture.scale)
            }
            object?.scale = newScale
            gesture.scale = CGFloat((object?.scale.x)!)
        default:
            gesture.scale = 1.0
            originalScale = nil
        }
    }