Scenekit - how can i drag and drop

Question

With the code shown below Im able to have a sphere in my scene.with a blue background... Im new to sceneKit in iOS.I want to know how we can move that object (drag the sphere)to another position(Drop).

    override func viewDidLoad() {
    super.viewDidLoad()
    sceneView = SCNView(frame: self.view.frame)
    sceneView.scene = SCNScene()
    self.view.addSubview(sceneView)


    let groundGeometry = SCNFloor()
    groundGeometry.reflectivity = 0
    let groundMaterial = SCNMaterial()
    groundMaterial.diffuse.contents = UIColor.blueColor()
    groundGeometry.materials = [groundMaterial]
    ground = SCNNode(geometry: groundGeometry)

    let camera = SCNCamera()
    camera.zFar = 10000
    self.camera = SCNNode()
    self.camera.camera = camera
    self.camera.position = SCNVector3(x: -20, y: 15, z: 20)
    let constraint = SCNLookAtConstraint(target: ground)
    constraint.gimbalLockEnabled = true
    self.camera.constraints = [constraint]

    let ambientLight = SCNLight()
    ambientLight.color = UIColor.darkGrayColor()
    ambientLight.type = SCNLightTypeAmbient
    self.camera.light = ambientLight

    let spotLight = SCNLight()
    spotLight.type = SCNLightTypeSpot
    spotLight.castsShadow = true
    spotLight.spotInnerAngle = 70.0
    spotLight.spotOuterAngle = 90.0
    spotLight.zFar = 500
    light = SCNNode()
    light.light = spotLight
    light.position = SCNVector3(x: 0, y: 25, z: 25)
    light.constraints = [constraint]

    let sphereGeometry = SCNSphere(radius: 1.5)
    let sphereMaterial = SCNMaterial()
    sphereMaterial.diffuse.contents = UIColor.greenColor()
    sphereGeometry.materials = [sphereMaterial]
    sphere1 = SCNNode(geometry: sphereGeometry)
    sphere1.position = SCNVector3(x: -15, y: 1.5, z: 0)


    sceneView.scene?.rootNode.addChildNode(self.camera)
    sceneView.scene?.rootNode.addChildNode(ground)
    sceneView.scene?.rootNode.addChildNode(light)

    sceneView.scene?.rootNode.addChildNode(sphere1)

}

Answer 1

Mee, I tried sceneKit with objective-c few months back may be it can help you generalize the solution. For drag and drop of nodes I used UIPanGestureRecognizer.

//Gesture Recognizer for panning (moving)

UIGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanFrom:)];
[[self view] addGestureRecognizer:panGestureRecognizer];

// Then in "handlePanFrom"

- (void)handlePanFrom:(UIPanGestureRecognizer *)recognizer {


    if (recognizer.state == UIGestureRecognizerStateChanged)
    {
        //Getting the new location of the view after pan gesture
        CGPoint translation = [recognizer translationInView:recognizer.view];

        //Converting this translation as per the SpriteKit coordinates
        translation = CGPointMake(translation.x, -translation.y);

        //Changing the position of sphere node with the translation
        CGPoint position = [sphere position];
        [sphere setPosition:CGPointMake(position.x + translation.x, position.y + translation.y)];

        //Resetting the values of recognizer
        [recognizer setTranslation:CGPointZero inView:recognizer.view];

    }
    else if (recognizer.state == UIGestureRecognizerStateEnded)
    {
        float scrollDuration = 1;
        CGPoint velocity = [recognizer velocityInView:recognizer.view];

        //Taking current position of sphere node
        CGPoint pos = [sphere position];

        //Finding change in position on the basis of velocity and scroll duration
        CGPoint p = mult(velocity, scrollDuration);

        //Calculating new position of the sphere
        CGPoint newPos = CGPointMake(pos.x + p.x, pos.y - p.y);

        [sphere removeAllActions];

        //Action for moving the sprite to the new location
        SKAction *moveTo = [SKAction moveTo:newPos duration:scrollDuration];
        [moveTo setTimingMode:SKActionTimingEaseOut];
        [sphere runAction:moveTo];
    }
}

For more help you can check this nice tutorial http://www.raywenderlich.com/44270/sprite-kit-tutorial-how-to-drag-and-drop-sprites