cesium获取鼠标的实时经纬度和高度信息。

      var cesiumViewer = this.viewer;
      var canvas = cesiumViewer.scene.canvas;
      var ellipsoid = cesiumViewer.scene.globe.ellipsoid;
      var handler = new Cesium.ScreenSpaceEventHandler(canvas);
      handler.setInputAction(function(movement){
          //捕获椭球体，将笛卡尔二维平面坐标转为椭球体的笛卡尔三维坐标，返回球体表面的点
          var cartesian = cesiumViewer.camera.pickEllipsoid(movement.endPosition, ellipsoid);
          if(cartesian){
              //将笛卡尔三维坐标转为地图坐标（弧度）
              var cartographic = cesiumViewer.scene.globe.ellipsoid.cartesianToCartographic(cartesian);
              //将地图坐标（弧度）转为十进制的度数
              var lat = Cesium.Math.toDegrees(cartographic.latitude).toFixed(4);
              var lng = Cesium.Math.toDegrees(cartographic.longitude).toFixed(4);
              var height = (cesiumViewer.camera.positionCartographic.height/1000).toFixed(2);

              // console.log(lng+','+lat+","+height);
            _this.mousePosition = lng+", "+lat+", "+height;
          }
      },Cesium.ScreenSpaceEventType.MOUSE_MOVE)