Creating a Polygon

This example demonstrates how to create a polygon using an array of vertices and set basic properties. This example uses the ILinearRing, IGeometry, ITerrainPolygon80, ICreator80 (CreatePolygon, GeometryCreator), IGeometryCreator (CreateLinearRingGeometry, CreatePolygonGeometry) INavigate80 (FlyTo), and IPosition80 (Copy, Pitch) properties and methods.

 

private void GeometryPolygon()

        {

            string tMsg = String.Empty;

            double[] cVerticesArray = null;

            ILinearRing cRing = null;

            IGeometry cPolygonGeometry = null;

            ITerrainPolygon80 cPolygon = null;

 

            try

            {

                //

                // A. Instantiate TerraExplorer Object

                //

                var SGWorld = new SGWorld80();

 

                //

                // B.  Create linear ring

                //

                {

                    //B1. Create vertices double array, each point in format x,z,y

                    cVerticesArray = new double[] {

                        -122.415025,  37.76059,   10,

                        -122.415868,  37.760546,  11,

                        -122.415922,  37.761244,  12,

                        -122.415592,  37.761254,  13,

                        -122.415557,  37.760973,  14,

                        -122.415081,  37.76099,   15,

                    };

 

 

                    // B2. Create linear ring using vertices

                    {

                        cRing = SGWorld.Creator.GeometryCreator.CreateLinearRingGeometry(cVerticesArray);

                    }

                }

 

                //

                // C. Create polygon geometry using linear ring

                //

                {

                    cPolygonGeometry = SGWorld.Creator.GeometryCreator.CreatePolygonGeometry(cRing, null);

                }

 

                //

                // D. Create polygon using polygon geometry

                //

                {

                    // D1. Set polygon input params

                    uint nLineColor = 0xFF00FF00; // Abgr value -> solid green

                    uint nFillColor = 0x7FFF0000; // Abgr value -> 50% transparent blue

                    AltitudeTypeCode eAltitudeTypeCode = AltitudeTypeCode.ATC_TERRAIN_RELATIVE;

 

                    // D2. Create polygon

                    cPolygon = SGWorld.Creator.CreatePolygon(cPolygonGeometry, nLineColor, nFillColor, eAltitudeTypeCode, string.Empty, "Polygon");

                }

 

                //

                // E. FlyTo polygon

                //

                {

                    var cFlyToPos = cPolygon.Position.Copy();

                    cFlyToPos.Pitch = -89.0; // Set camera to look downward on polygon

                    SGWorld.Navigate.FlyTo(cFlyToPos, ActionCode.AC_FLYTO);

                }

            }

            catch (Exception ex)

            {

                tMsg = String.Format("GeometryPolygon_Click Exception: {0}", ex.Message);

                MessageBox.Show(tMsg);

            }

        }