title: THREE.js: Punch hole in Shape with another Shape
body: <p>I am using the D3-threeD2.js to translate SVG files into <code>THREE.Shape</code>(s) that I can then extrude with three.js. It works fine except for holes.</p>
  
  <p>Lets say I have a donut shape: a disc with a hole inside. The library gives me one <code>THREE.Shape</code> that represents the disc and one <code>THREE.Shape</code> that represents the hole.</p>
  
  <p>I know I can punch a hole in the disc if I have a <code>THREE.Path</code>, but I don't - I have a <code>THREE.Shape</code>.</p>
  
  <p>So is there a way to get a <code>THREE.Path</code> from a <code>THREE.Shape</code>? Or alternatively is there a way to punch a hole in a <code>THREE.Shape</code> with another <code>THREE.Shape</code>?</p>