获取三维经纬度

      var handler = new Cesium.ScreenSpaceEventHandler(viewer.scene.canvas);
      var that = this;
      handler.setInputAction(function(e) {
    
    var position = window.viewer.scene.pickPosition(e.position);
        var ellipsoid = window.viewer.scene.globe.ellipsoid;
        var cartesian3 = new Cesium.Cartesian3(
          position.x,
          position.y,
          position.z
        );
        var cartographic = ellipsoid.cartesianToCartographic(cartesian3);
        var lat = Cesium.Math.toDegrees(cartographic.latitude);
        var lng = Cesium.Math.toDegrees(cartographic.longitude);
        var alt = cartographic.height;
　　　　　// 依次是经度，纬度，高度
        console.log(lng+‘-----‘+lat+‘--‘+alt);
    }, Cesium.ScreenSpaceEventType.LEFT_CLICK);