title: How to detect which SCNNode has been touched ARKit
body: <p>I'm having some troubles with SCNode hit detection. I need to detect which object was touched in the scene having a SCNNode, I have implemented this piece of code but it seems crashing when I'm touching the object but working good when I'm touching the rest of the sceneView.</p>
  
  <pre><code>override func touchesBegan(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
          let touch = touches.first as! UITouch
          if(touch.view == self.sceneView){
              print("touch working")
              let viewTouchLocation:CGPoint = touch.location(in: sceneView)
              guard let result = sceneView.hitTest(viewTouchLocation, options: nil).first else {
                  return
              }
              if (bottleNode?.contains(result.node))! { //bottleNode is declared as  SCNNode? and it's crashing here
                  print("match")
              }
  
          }
      }
  </code></pre>