SkylineGlobe 6.5 如何实现简单多边形的动态绘制 C#示例代码

在Skyline的TEPro软件中，我们可以很容易地绘制出多边形。

那么，在二次开发过程中，该如何绘制一个简单的多边形呢？

通过下面的示例代码，我们可以很容易完成这一项工作。

其中，重点需要了解Geometry对象的定义和使用。

 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
 using System.Drawing;
 using System.Linq;
 using System.Text;
 using System.Windows.Forms;
 using TerraExplorerX;

 namespace HelloSkyline
 {
     public partial class CTerrainPolygon: Form
     {
         SGWorld65 sgworld = null;
         String pbhander = "";
         ITerrainPolygon65 pITPolygon = null;
         List<double> ListVerticsArray = new List<double>();

         public CTerrainPolygon()
         {
             InitializeComponent();

             sgworld = new SGWorld65();
             sgworld.OnLButtonDown += new _ISGWorld65Events_OnLButtonDownEventHandler(sgworld_OnLButtonDown);
             sgworld.OnRButtonDown += new _ISGWorld65Events_OnRButtonDownEventHandler(sgworld_OnRButtonDown);
         }

         bool sgworld_OnRButtonDown(int Flags, int X, int Y)
         {
             sgworld.Window.SetInputMode(MouseInputMode.MI_FREE_FLIGHT);
             pbhander = "";
             pITPolygon = null;
             return true;
         }

         bool sgworld_OnLButtonDown(int Flags, int X, int Y)
         {
             IWorldPointInfo65 pIWPInfo = sgworld.Window.PixelToWorld(X, Y, WorldPointType.WPT_TERRAIN);
             IPosition65 pIPosition = sgworld.Navigate.GetPosition(AltitudeTypeCode.ATC_ON_TERRAIN);

             if (pbhander == "TerrainPolygon")
             {
                 if (pITPolygon == null)
                 {
                     ILinearRing cRing = null;
                     double[] cVerticesArray = null;
                     cVerticesArray = new double[] {
                         pIPosition.X,  pIPosition.Y,  ,
                         pIWPInfo.Position.X,  pIWPInfo.Position.Y,  pIWPInfo.Position.Distance,
                         pIWPInfo.Position.X,  pIWPInfo.Position.Y,  pIWPInfo.Position.Distance,
                             };
                     cRing = sgworld.Creator.GeometryCreator.CreateLinearRingGeometry(cVerticesArray);

                     uint nLineColor = 0xFF00FF00;
                     uint nFillColor = 0x7FFF0000;
                     AltitudeTypeCode eAltitudeTypeCode = AltitudeTypeCode.ATC_ON_TERRAIN;
                     string gid = CreateGroup("AnalysisTEMP");
                     pITPolygon = sgworld.Creator.CreatePolygon(cRing, nLineColor, nFillColor, eAltitudeTypeCode, gid, "Polygon");

                     IPolygon polygonGeometry = pITPolygon.Geometry as IPolygon;
                     polygonGeometry.StartEdit();
                     foreach (ILinearRing ring in polygonGeometry.Rings)
                     {
                         double dx = pIWPInfo.Position.X;
                         double dy = pIWPInfo.Position.Y;
                         double dh = pIWPInfo.Position.Distance;
                         ring.Points.AddPoint(dx, dy, dh);
                         ring.Points.DeletePoint();
                     }
                     IGeometry editedGeometry = polygonGeometry.EndEdit();
                     pITPolygon.Geometry = editedGeometry;
                 }
                 else
                 {
                     IPolygon polygonGeometry = pITPolygon.Geometry as IPolygon;
                     polygonGeometry.StartEdit();
                     foreach (ILinearRing ring in polygonGeometry.Rings)
                     {
                         double dx = pIWPInfo.Position.X;
                         double dy = pIWPInfo.Position.Y;
                         double dh = pIWPInfo.Position.Distance;
                         ring.Points.AddPoint(dx, dy, dh);
                     }
                     IGeometry editedGeometry = polygonGeometry.EndEdit();
                     pITPolygon.Geometry = editedGeometry;
                 }
             }
             return false;
         }

         private void button1_Click(object sender, EventArgs e)
         {
             pbhander = "TerrainPolygon";
             sgworld.Window.SetInputMode(MouseInputMode.MI_COM_CLIENT);
         }

         private void button2_Click(object sender, EventArgs e)
         {
             string gid = sgworld.ProjectTree.FindItem("AnalysisTEMP");
             if (gid != null && gid != "")
             {
                 sgworld.ProjectTree.DeleteItem(gid);
             }
         }

         private String CreateGroup(String GroupName)
         {
             string gid = sgworld.ProjectTree.FindItem(GroupName);
             if (gid != null && gid != "")
             {
                 return gid;
             }
             else
             {
                 return sgworld.ProjectTree.CreateLockedGroup(GroupName);
             }
         }
     }
 }