title: GUI system for three.js
body: <p>What is a good approach to "attaching" GUI controls such as forms, buttons, checkboxes etc to objects in a three.js scene?</p>
  
  <p>i.e., I'd like to show a 3D model, let the user click and pick things in that model, and see a pop-up menu that leads him to forms that let him set its properties, do other actions etc.</p>
  
  <p>(A rough equivalent probably would be <a href="http://jmonkeyengine.org/wiki/doku.php/jme3:advanced:nifty_gui" rel="noreferrer">Nifty GUI</a> if I were to use JMonkeyEngine.)</p>