// 一、經(jīng)緯度轉(zhuǎn)換為世界坐標(biāo)
    Cesium.Cartesian3.fromDegrees(longitude, latitude, height, ellipsoid, result) 
    var ellipsoid=viewer.scene.globe.ellipsoid;
    var cartographic=Cesium.Cartographic.fromDegrees(lng,lat,alt);
    var cartesian3=ellipsoid.cartographicToCartesian(cartographic);
    
//  二、 世界坐標(biāo)轉(zhuǎn)換為經(jīng)緯度
     var ellipsoid=viewer.scene.globe.ellipsoid;
     var cartesian3=new Cesium.cartesian3(x,y,z);
     var cartographic=ellipsoid.cartesianToCartographic(cartesian3);
     var lat=Cesium.Math.toDegrees(cartograhphic.latitude);
     var lng=Cesium.Math.toDegrees(cartograhpinc.longitude);
     var alt=cartographic.height;2.Cartographic.fromCartesian

// 三、屏幕坐標(biāo)和世界坐標(biāo)相互轉(zhuǎn)換
    var pick1= new Cesium.Cartesian2(0,0); 
    var cartesian = viewer.scene.globe.pick(viewer.camera.getPickRay(pick1),viewer.scene);
    
    
    Cesium.SceneTransforms.wgs84ToWindowCoordinates(scene, Cartesian3);