title: THREE.js, Orthographic Camera, find x and z where y=0
body: <p>This code works on the perspective camera:</p>
  
  <pre><code>var vector = new THREE.Vector3((mouseX / window.innerWidth) * 2 - 1, -(mouseY / window.innerHeight) * 2 + 1, 0.5);
  vector.unproject(camera);
  var dir = vector.sub(camera.position).normalize();
  var distance = -camera.position.y / dir.y;
  var cursor3DPos = camera.position.clone().add(dir.multiplyScalar(distance));
  </code></pre>
  
  <p>How do I get the same 3D coordinates using an Orthographic Camera?</p>