cesium1.126显示等高线

上代码
1.先初始化一个viewer
  vw = new Cesium.Viewer('map-container', {
                    baseLayerPicker: false,
                    baseLayer: false,//取消默认的地形图
                    animation: false,
                    shouldAnimate: false, //是否允许动画
                    selectionIndicator: false,
                    fullscreenButton: false,
                    geocoder: false,
                    homeButton: false,
                    infoBox: false,
                    sceneModePicker: false,
                    timeline: false,
                    navigationHelpButton: false,
                    navigationInstructionsInitiallyVisible: false,
                    showRenderLoopErrors: false,
                    shadows: false,
                    terrain: Cesium.Terrain.fromWorldTerrain()//这个是用来测试的地形图,所以要显示
                }); 
2.设置等高线函数
  et_dgx_render: function () {
            var sl = Cesium.Material.fromType('ElevationContour');
            sl.uniforms.color = new Cesium.Color(0, 0, 0.2,0.75);
            sl.uniforms.spacing = 100;
            sl.uniforms.wdith = 20;
            vw.scene.globe.material = sl;//一个单词写错了
// 设置材质globe.material= material;
        }, 
                