title: Getting Viewer 3DObjects in Scene
body: <p>I'm trying to generate a pdf from the viewer adapting <a href="https://github.com/fjenett/threejs-pdf-renderer" rel="nofollow noreferrer">threejs-pdf-renderer</a> library. 
  This PDFRenderer needs a Scene and a Camera object in its render method.
  As per the library example, I should create or pass a scene containing children but when I try with my autodesk-Viewer sample app, the viewer's scene children array (<code>viewer.impl.scene</code> and <code>viewer.impl.sceneAfter</code>) is always empty and I always get a blank PDF. </p>
  
  <p>Is having the viewer's scene children empty as expected? If so, how can I get all drawn elements in order to add it to a new Scene so I can pass this parameter to the PDfRenderer's render method?</p>
  
  <p>I've been trying different solutions without success, even tried adding 
  <code>viewer.model.getConsolidation().meshes</code> array to a scene, but I think it's not the correct way.</p>
  
  <p>Thanks in advance.</p>