function init() {
        // 创建一个场景
        var scene = new THREE.Scene();

        // 创建一个摄像机，它定义了我们的观察位置
        var camera = new THREE.PerspectiveCamera(35, window.innerWidth / window.innerHeight, 0.1, 1000);
        camera.position.x = 300;
        camera.position.y = 200;
        camera.position.z = 100;

        // 创建一个渲染器并设置其大小
        var renderer = new THREE.WebGLRenderer();

        renderer.setClearColor(0xffffff);
        renderer.setSize(window.innerWidth, window.innerHeight);
  
        var cubeGeometry = new THREE.CubeGeometry(30,30,30);
        var sphereGeometry = new THREE.SphereGeometry(20, 100, 100);
  
        const mixers = [];
        const clock = new THREE.Clock();
        // 线框
        var cubeWireMaterial = new THREE.MeshBasicMaterial({ wireframe: true, color: 0x666666 });
        var cubeMeshWire = new THREE.Mesh(cubeGeometry, cubeWireMaterial);
        cubeMeshWire.position.set(0, 0, 0);
        scene.add(cubeMeshWire);
  
        // 上下移动动画
        const mixer = new THREE.AnimationMixer(cubeMeshWire);
        const action = mixer.clipAction(getClip());
        action.timeScale = 1;
        action.loop = THREE.LoopPingPong;
        action.play();
        mixers.push(mixer);
  
  
        // 创建一个平行光并设置其位置
        var directionalLight = new THREE.DirectionalLight(0xffffff, 0.7);
        directionalLight.position.set(-20, 40, 60);
        scene.add(directionalLight);

        // 增加一个环境光，提亮整个场景
        var ambientLight = new THREE.AmbientLight(0x292929);
        scene.add(ambientLight);

        // 将渲染器的输入（canvas）插入到特定 DOM 元素下
        document.getElementById("webgl").appendChild(renderer.domElement);

 
        // 确保摄像机第一时刻是看向场景中心（0,0,0）
        camera.lookAt(scene.position);
        render();
  
        function getClip() {
          const times = [0, 1]; // 关键帧时间数组，离散的时间点序列
          const values = [0, 0, 0, 0, 10, 0]; // 与时间点对应的值组成的数组
          // 创建位置关键帧对象：0时刻对应位置0, 0, 0   10时刻对应位置150, 0, 0
          const posTrack = new THREE.VectorKeyframeTrack('stone.position', times, values);
          const duration = 1;
          return new THREE.AnimationClip('stonePosClip', duration, [posTrack]);
        }

        function render() {
            const delta = clock.getDelta();
            mixers.forEach((mixer) => mixer.update(delta))
            // render using requestAnimationFrame
            requestAnimationFrame(render);
            renderer.render(scene, camera);
        }
    }
    window.onload = init