SkylineGlobe TerraExplorer for Web 7.1.0版本 接口示例

在SkylineGlobe TerraExplorer for Web 7.1.0版本（俗称H5免插件版本）中，如何使用SGWorld接口的三维视域分析方法呢？

请参考下面的示例：

通过下面的代码大家不难发现，这个函数方法是基于Cesium的接口重新封装的，示例代码里面也混杂了一些Cesium的接口，

这样看，如果以后我们要用Skyline的这个H5免插件版本做开发，Cesium的接口也要一并学习啦。

var MyViewshedTool = function () {

    //SET TOOL ID   

    this.getId = function () {

        return 'MyViewshedTool';

    },

        //SET MENU ENTRY FOR THE TOOL (See example 1 for more details)

        this.getMenuEntry = function () {

            return TerraExplorer.tools.MenuEntry.addToSidebar(this, "My Viewshed Tool", "./userTools/myToolIcon.png", 3, TerraExplorer.tools.MenuEntry.MenuEntryAnalysis(), "My Tools");

        },

        //SET CODE TO EXECUTE WHEN TOOL IS CLICKED IN SIDEBAR

        this.open = function () {

            //CREATE A MESH LAYER USING THE CreateMeshLayer METHOD

            var promise = TerraExplorer.SGWorld.Creator.CreateMeshLayer("Frederick", "http://www.SkylineGlobe.com/SG/streamer.ashx", "Frederick_4TEDF", true);

            promise.then(function (teObject) {

                //PRINT DESCRIPTION OF ADDED LAYER

                console.log("Created Mesh layer: " + teObject.description);

                //FLY TO Frederick USING THE camera.flyTo METHOD

                viewer.camera.flyTo({

                    destination: new Cesium.Cartesian3.fromDegrees(-77.40982, 39.41875, 600), //Frederick coordinates

                    orientation: {

                        heading: Cesium.Math.toRadians(180.0),

                        pitch: Cesium.Math.toRadians(-55.0),

                        roll: 0.0

                    },

                    complete: function () {

                        var hpra = new Cesium.HeadingPitchRange(Cesium.Math.toRadians(90.0), -45, 2000);

                        var vsPositionCarto = new Cesium.Cartesian3.fromDegrees(-77.41319, 39.41702, 300); //Other Frederick coordinates

                        //CREATE VIEWSHED OBJECT USING THE CreateViewshedObject METHOD

                        TerraExplorer.SGWorld.Analysis.CreateViewshedObject('Viewshed On Frederick', vsPositionCarto, 53, 53, hpra, { roll: 0.0 });

                    }

                });

            }).otherwise(function (err) {

                alert(err);

            });

            return true;

        }

};