问物体上的光反射盘3-js

EN

//renderer
    renderer = new THREE.WebGLRenderer( { canvas : spaceCanvas} );
    renderer.setSize( 672, 472 );
    renderer.shadowMap.enabled = true;
    renderer.shadowMap.renderReverseSided = false;
//mainScene
    mainScene = new THREE.Scene();
    mainCamera = new THREE.PerspectiveCamera( 45, window.innerWidth /window.innerHeight, 0.01, 2000 );
    mainCamera.position.z = 2.25;
//Lighting
    var ambLight    = new THREE.AmbientLight( 0x222222 );
    var light   = new THREE.DirectionalLight( 0xffffff, 1 );
    light.position.set(5,3,5);
    light.castShadow = true;
    light.shadow.camera.near = 0.01;
    light.shadow.camera.far = 15;
    light.shadow.camera.fov = 45;
    light.shadow.camera.left = -1;
    light.shadow.camera.right =  1;
    light.shadow.camera.top =  1;
    light.shadow.camera.bottom = -1;
    /*light.shadowCameraVisible = true;*/
    light.shadow.bias = 0.001;
    light.shadow.mapSize.width = 672;
    light.shadow.mapSize.height = 472;
    mainScene.add(light, ambLight);

function CreateEarth(){
earth = new THREE.Object3D();
THREE.crossOrigin = "";
    var loader = new THREE.TextureLoader();
    var colorMap = loader.load("img/bodies/earth/colorMap.jpg");
    var bumpMap = loader.load("img/bodies/earth/bump.jpg");
    var specMap = loader.load("img/bodies/earth/specular.jpg");
    var earthGeometry = new THREE.SphereGeometry( 0.5, 32, 32 );
    var earthMaterial = new THREE.MeshPhongMaterial({
        map : colorMap,
        bumpMap : bumpMap,
        bumpScale : 0.05,
        specularMap : specMap,
        specular : new  THREE.Color("grey"),
        shininess: 25
    });
    earthMesh = new THREE.Mesh(earthGeometry, earthMaterial );
    earth.add(earthMesh);

function CreateEarthAtmosphere(){
    var loader = new THREE.TextureLoader();
    var cloudTexColorMap = loader.load("img/bodies/earth/cloudTexture.png");

    var atmosphereGeometry = new THREE.SphereGeometry(0.51, 32, 32);
    var atmosphereMaterial = new THREE.MeshPhongMaterial({
            map : cloudTexColorMap,
            /*alphaMap : cloudTexTransMap,*/
            side : THREE.DoubleSide,
            opacity : 0.5,
            transparent : true,
            depthWrite : false
    });
    atmosphereMesh = new THREE.Mesh(atmosphereGeometry, atmosphereMaterial);
    earthMesh.add(atmosphereMesh)
}