Three.js Can'；t设置加载模型的材质

你能帮我找出材料不适用于网格的原因吗

-使用三个加载模型。MeshNormalMaterial（）。 -尝试加载纹理-不正常。 我使用makehuman.org创建模型，将模型保存为obj，然后在grunt three obj的帮助下将obj转换为json 我认为我做的每件事都是对的……但在某些地方我错了，犯了错误：

Uncaught TypeError: Cannot set property 'needsUpdate' of undefined 

代码：

致以最良好的问候。安东

var angle = .05,
    scene = new THREE.Scene(),
    camera = new THREE.PerspectiveCamera(63, 4/3, 0.1, 1000),
    renderer = new THREE.WebGLRenderer({
      canvas: document.getElementById("screen"),
      antialias: true
    }),
    json_loader = new THREE.JSONLoader(),
    model = null

    json_loader.load('http://websaints.net/model/json/human.js', modelLoaded, 'http://websaints.net/model/json/');

    renderer.setSize(600, 400);
    camera.position.x = 0;
    camera.position.y = 0;
    camera.position.z = -10;

    function render() {
      if(model!=null){
        model.rotation.y+=.05;
      }
      requestAnimationFrame(render);
      renderer.render(scene, camera);
    }
    render();

    function modelLoaded(geometry, materials){
      model = new THREE.Mesh(geometry, new THREE.MeshNormalMaterial());
      model.position.z = 10;
      model.position.y = -8;
      scene.add(model);
      camera.lookAt({x:0,y:0,z:0});
    }