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var camera, scene, renderer, mesh, material, stats;
init();
animate();

function init() {
  // Renderer.
  renderer = new THREE.WebGLRenderer();
  //renderer.setPixelRatio(window.devicePixelRatio);
  renderer.setSize(window.innerWidth, window.innerHeight);
  // Add renderer to page
  document.body.appendChild(renderer.domElement);

  // Create camera.
  camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 1, 1000);
  camera.position.z = 400;

  // Create scene.
  scene = new THREE.Scene();

  // Create material
  material = new THREE.MeshPhongMaterial();

  // Create cube and add to scene.
  var geometry = new THREE.BoxGeometry(200, 200, 200);
  mesh = new THREE.Mesh(geometry, material);
  scene.add(mesh);

  // Create ambient light and add to scene.
  var light = new THREE.AmbientLight(0x404040); // soft white light
  scene.add(light);

  // Create directional light and add to scene.
  var directionalLight = new THREE.DirectionalLight(0xffffff);
  directionalLight.position.set(1, 1, 1);
  scene.add(directionalLight);

  // Add listener for window resize.
  window.addEventListener('resize', onWindowResize, false);

  // Add stats to page.
  stats = new Stats();
  document.body.appendChild(stats.dom);
}

function animate() {
  requestAnimationFrame(animate);
  mesh.rotation.x += 0.005;
  mesh.rotation.y += 0.01;
  renderer.render(scene, camera);
  stats.update();
}

function onWindowResize() {
  camera.aspect = window.innerWidth / window.innerHeight;
  camera.updateProjectionMatrix();
  renderer.setSize(window.innerWidth, window.innerHeight);
}

body {
  padding: 0;
  margin: 0;
}

canvas {
  display: block;
}