// VRcore.js
 import * as THREE from 'three';
 const OrbitControls = require('three-orbit-controls')(THREE)
 let Scene, Camera, Renderer, Controls, loopID;

 function createScene({domContainer = document.body, fov = 50,far = 1000}){
 if (!(domContainer instanceof HTMLElement)) {
  throw new Error('domContainer is not a HTMLElement!');
 }
 // 初始化 scene
 Scene = new THREE.Scene();
 // 初始化 camera
 Camera = new THREE.PerspectiveCamera(fov, domContainer.clientWidth / domContainer.clientHeight, 1, far);
 Camera.position.set( 200, 200, 200 );
 Camera.lookAt(Scene.position);
 Scene.add(Camera);
 // 初始化 renderer
 Renderer = new THREE.WebGLRenderer({ canvas: domContainer, antialias: true, alpha: true } );
 Renderer.clear();
 Renderer.setClearColor( 0xeeeeee, 1); // 更改渲染器颜色
 Renderer.setSize(domContainer.clientWidth, domContainer.clientHeight);
 Renderer.shadowMap.Enabled = true;
 Renderer.setPixelRatio(domContainer.devicePixelRatio);
 initVR();
 }
 function initVR() {
  // 初始化控制器
  Controls = new OrbitControls(Camera, Renderer.domElement);;
  Controls.addEventListener('change', render);
  Controls.enableZoom = true;
 }
 function render() {
 Renderer.render(Scene, Camera);
 }
 function renderStart(callback) {
 loopID = 0; // 记录循环几次，后面有与清除场景中的物体
 if (loopID === -1) return;
 let animate = function(){
  loopID = requestAnimationFrame(animate);
  callback();
  Controls.update();
  render();
 }
 animate();
 }
 // 暂停动画渲染
 function renderStop() {
 if (loopID !== -1) {
  window.cancelAnimationFrame(loopID);
  loopID = -1;
 }
 }
 // 回收当前场景
 function clearScene() {
 for(let i = Scene.children.length - 1; i >= 0; i-- ) {
  Scene.remove(Scene.children[i]);
 }
 }
 // 清理页面
 function cleanPage() {
 renderStop();
 clearScene();
 }
 export {
 Scene,
 Camera,
 Renderer,
 Controls,
 createScene,
 initVR,
 renderStart,
 renderStop,
 clearScene,
 cleanPage
 }

 // VRpage.js
 import * as THREE from 'three';
 import * as VRcore from './VRcore.js';
 export default class VRpage {
 constructor(options) {
  // 创建场景
  VRcore.createScene(options);
  this.start();
  this.loadPage();
 }
 loadPage() {
  VRcore.renderStart(() => this.update());
  this.loaded();
 }
 initPage() {
  this.loadPage();
  this.start();
 }
 start() {}
 loaded() {}
 update() {}
 }

 // page.js
 import * as THREE from 'three';
 import VRpage from '../../utils/VRpage.js';
 import * as VRcore from '../../utils/VRcore.js';
 export default class Page extends VRpage {
 start() { // 启动渲染之前，创建场景3d模型
  let geometry = new THREE.CubeGeometry(100,100,100);
  let material = new THREE.MeshLambertMaterial( { color:0x0000ff} );
  this.box = new THREE.Mesh(geometry,material);
  this.box.position.set(3, -2, -3);
  const PointLight = new THREE.PointLight(0xffffff);
  PointLight.position.set(500, 500, 500);
  const AmbientLight = new THREE.AmbientLight( 0x404040 ); // soft white light
  VRcore.Scene.add(PointLight);
  VRcore.Scene.add(AmbientLight);
  VRcore.Scene.background = new THREE.Color( 0xeeeeee ); // 更改场景背景色
  VRcore.Scene.add(this.box);
 }
 update() {
  this.box.rotation.y += 0.01;
 }
 }

 // index.js
 import React, { Component } from 'react';
 import PropTypes from 'prop-types';
 import Page from './Page.js';
 class Oho extends Component {
 constructor() {
  super();
  this.init = this.init.bind(this);
 }
 componentDidMount() {
  const dom = document.querySelector('#Oho');
  this.init(dom);
 }
 init(dom) {
  const page = new Page({domContainer: dom});
 }
 render() {
  return (
  <div className="three-demo">
   <canvas id="Oho" ref="camera"></canvas>
  </div>
  );
 }
 }
 export default Oho;