title: Get All ARAnchors of focused Camera in ARKIT
body: <blockquote>
    <p>When application launched first a vertical surface is detected on one wall than camera focus to the second wall, in the second wall another surface is detected. The first wall is now no more visible to the ARCamera but this code is providing me the anchors of the first wall. but I need anchors of the second wall which is right now Visible/focused in camera.</p>
  </blockquote>
  
  <pre><code>if let anchor = sceneView.session.currentFrame?.anchors.first {
      let node = sceneView.node(for: anchor)
      addNode(position: SCNVector3Zero, anchorNode: node)
  } else {
      debugPrint("anchor node is nil")
  }
  </code></pre>