title: ARKit: Finding the coordinates of a SCNNode on the screen
body: <p>I have a simple Swift ARKit setup where I have a SCNNode with a 3D object that is visible in an ARSCNView.</p>
  
  <p>I want to determine the 2D coordinates of this object on the ARSCNView. By this I mean the x- and y-coordinates the object has when it is drawn onto the screen. </p>
  
  <p>I have provided a sketch to illustrate what I mean:
  <img src="https://i.stack.imgur.com/cfcMn.png" alt="Sketch"></p>
  
  <p>Is there a way to get these coordinates, or at least an approximation? I need this in order to do some further processing with the camera frame. Basically I am interested in the area the object occupies on the screen.</p>