Three.JS

Question

我生成一个随机平面，该平面动画顶点中的运动以产生结晶效果。当我使用常规PlaneGeometry时，着色不是问题：http://codepen.io/shshaw/pen/GJppEX

但是，我尝试切换到PlaneBufferGeometry以查看是否可以获得更好的性能，但阴影消失了。 http://codepen.io/shshaw/pen/oXjyJL?editors=001

var planeGeometry = new THREE.PlaneBufferGeometry(opts.planeSize, opts.planeSize, opts.planeDefinition, opts.planeDefinition),
    planeMaterial = new THREE.MeshLambertMaterial({
      color: 0x555555,
      emissive: 0xdddddd,
      shading: THREE.NoShading
    }),
    plane = new THREE.Mesh(planeGeometry, planeMaterial),
    defaultVertices = planeGeometry.attributes.position.clone().array;

  function randomVertices() {
    var vertices = planeGeometry.attributes.position.clone().array;
    for (var i = 0; i <= vertices.length; i += 3) {
      // x
      vertices[i] = defaultVertices[i] + (rand(-opts.variance.x, opts.variance.x));
      // y
      vertices[i + 1] = defaultVertices[i + 1] + (rand(-opts.variance.y, opts.variance.y));
      // z
      vertices[i + 2] = rand(-opts.variance.z, -opts.variance.z);
    }
    return vertices;
  }

  plane.geometry.attributes.position.array = randomVertices();

正如我看到建议的in this answer to 'Shading on a plane'，我试过了：

plane.geometry.computeVertexNormals();

在渲染时，我已经尝试了几何的所有以下属性，以确保它更新法线和＆amp ;;顶点，就像我在PlaneGeometry的工作示例中所做的那样：

plane.geometry.verticesNeedUpdate = true;
plane.geometry.normalsNeedUpdate = true;
plane.geometry.computeVertexNormals();
plane.geometry.computeFaceNormals();
plane.geometry.normalizeNormals();

阴影发生了什么变化？我可以将它带回PlaneBufferGeometry网格，还是需要坚持使用PlaneGeometry？

谢谢！