title: ThreeJS - GLTF loaded but not appearing
body: <p>I loaded a GLTF in ThreeJS, and I see in the console <code>GLTFLoader: 37.4208984375ms</code>, but it's not showing up in the scene, and I don't understand why.  Also, I used some boilerplate from the ThreeJS website.  Here's what the code looks like:</p>
  
  <pre><code>var camera, scene, renderer;
  var geometry, material, mesh;
  
  init();
  animate();
  
  function init() {
  
  camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 0.01, 10 );
  camera.position.set(20,0,20);
  
  scene = new THREE.Scene();
  
  // Instantiate a loader
  var loader = new THREE.GLTFLoader();
  
  // Load a glTF resource
  loader.load( 'Box.gltf', function ( gltf ) {
      scene.add( gltf.scene );
      gltf.animations; // Array&lt;THREE.AnimationClip&gt;
      gltf.scene;      // THREE.Scene
      gltf.scenes;     // Array&lt;THREE.Scene&gt;
      gltf.cameras;    // Array&lt;THREE.Camera&gt;
  } );
  
  var light = new THREE.AmbientLight(0xffffff);
  scene.add(light);
  
  renderer = new THREE.WebGLRenderer( { antialias: true } );
  renderer.setSize( window.innerWidth, window.innerHeight );
  document.body.appendChild( renderer.domElement );
  
  }
  
  function animate() {
    requestAnimationFrame( animate );
    renderer.render( scene, camera );
  
  }
  </code></pre>
  
  <p>So what am I doing wrong here?  Am I missing something?</p>