3D模型展示：交互体验与下载教程

3. 创建示例模型

编写简单的HTML和JavaScript代码，创建并加载一个立方体模型。以下是一个示例：

function init() {
    const scene = new THREE.Scene();
    const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
    const renderer = new THREE.WebGLRenderer();
    
    renderer.setSize(window.innerWidth, window.innerHeight);
    document.body.appendChild(renderer.domElement);

    // 添加一个立方体模型
    function createBox() {
        const geometry = new THREE.BoxGeometry(2, 2, 2);
        const material = new THREE.MeshBasicMaterial({ color: 0xff0000 });
        return new THREE.Mesh(geometry, material);
    }
    
    const cube = createBox();
    scene.add(cube);
    
    camera.position.z = 5;
    
    function animate() {
        requestAnimationFrame(animate);
        cube.rotation.x += 0.01;
        cube.rotation.y += 0.01;
        renderer.render(scene, camera);
    }
    init();
    animate();