using System;  
 using System.Collections.Generic;  
 using System.Linq;  
 using System.Text;  
 using ThinkGeo.MapSuite.Core;  
 
 namespace GreatCircleOnPacificRim  
 {  
     //This class, inheriting from Projection, applies the very simple projection of offsetting all the points  
     //360 degrees to the left.  
 
     class OffsetProjection: Projection, IDisposable  
     {  
         protected override Vertex[] ConvertToExternalProjectionCore(double[] x, double[] y)  
         {  
 
             Vertex[] vertices = new Vertex[x.Length];  
 
             for (int i = 0; i < vertices.Length; i++)  
             {  
                 vertices[i] = new Vertex(x[i] - 360, y[i]);  
             }  
             return vertices;  
         }  
 
         protected override Vertex[] ConvertToInternalProjectionCore(double[] x, double[] y)  
         {  
             Vertex[] vertices = new Vertex[x.Length];  
 
             for (int i = 0; i < vertices.Length; i++)  
             {  
                 vertices[i] = new Vertex(x[i] + 360, y[i]);  
             }  
             return vertices;  
         }  
 
         public void Dispose()  
         {  
             Dispose(true);  
             GC.SuppressFinalize(this);  
         }  
 
         private void Dispose(bool disposing)  
         {  
             Close();  
         }  
 
     }  
 }  
 

 using System;  
 using System.Collections.Generic;  
 using System.Linq;  
 using System.Windows.Forms;  
 
 namespace GreatCircleOnPacificRim  
 {  
     static class Program  
     {  
         /// <summary>  
         /// The main entry point for the application.  
         /// </summary>  
         [STAThread]  
         static void Main()  
         {  
             Application.EnableVisualStyles();  
             Application.SetCompatibleTextRenderingDefault(false);  
             Application.Run(new TestForm());  
         }  
     }  
 }  
 

 using System;  
 using System.Collections.ObjectModel;  
 using System.Drawing;  
 using System.Windows.Forms;  
 using ThinkGeo.MapSuite.Core;  
 
 namespace GreatCircleOnPacificRim  
 {  
     public partial class TestForm : Form  
     {  
         private MapEngine mapEngine = new MapEngine();  
         private Bitmap bitmap = null;  
 
        public TestForm()  
         {  
             InitializeComponent();  
         }  
 
         private void TestForm_Load(object sender, EventArgs e)  
         {  
             mapEngine.BackgroundFillBrush = new GeoSolidBrush(GeoColor.GeographicColors.ShallowOcean);  
 
             //We are loading the same ShapeFile twice: Once unprojected and a second time projecting  
             //all the features 360 degrees to the left.  
             ShapeFileFeatureLayer worldLayer = new ShapeFileFeatureLayer(@"..\..\Data\countries02.shp");  
             worldLayer.ZoomLevelSet.ZoomLevel01.DefaultAreaStyle = AreaStyles.Country1;  
             worldLayer.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;  
             mapEngine.StaticLayers.Add("WorldLayer", worldLayer);  
 
             OffsetProjection offsetProj = new OffsetProjection();  
 
             //Loads the country layer with the Projection offsetting all the features 360 degrees to the left.  
             ShapeFileFeatureLayer worldLayerOffset = new ShapeFileFeatureLayer(@"..\..\Data\countries02.shp", @"..\..\Data\countries_offset.idx");  
             worldLayerOffset.ZoomLevelSet.ZoomLevel01.DefaultAreaStyle = AreaStyles.Country1;  
             worldLayerOffset.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;  
             worldLayerOffset.FeatureSource.Projection = offsetProj;  
             mapEngine.StaticLayers.Add("World Offset", worldLayerOffset);  
 
             //InMemoryFeatureLayer for the cities.  
             InMemoryFeatureLayer cityPoints = new InMemoryFeatureLayer();  
             cityPoints.Open();  
             cityPoints.Columns.Add(new FeatureSourceColumn("LabelName"));  
             cityPoints.Close();  
             cityPoints.ZoomLevelSet.ZoomLevel01.DefaultPointStyle = PointStyles.City1;  
             cityPoints.ZoomLevelSet.ZoomLevel01.DefaultTextStyle = new TextStyle("LabelName", new GeoFont("Arial", 10), new GeoSolidBrush(GeoColor.SimpleColors.Black));  
             cityPoints.ZoomLevelSet.ZoomLevel01.DefaultTextStyle.XOffsetInPixel = 15;  
             cityPoints.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;  
             mapEngine.DynamicLayers.Add("City Points", cityPoints);  
 
             //Display the feature for Los Angeles as is (without projection) because it is on the unprojected layer.  
             PointShape LA_Point = new PointShape(-118.55, 34.08);  
             Feature LA_feature = new Feature(LA_Point);  
             LA_feature.ColumnValues.Add("LabelName", "Los Angeles");  
             cityPoints.InternalFeatures.Add("LA", LA_feature);  
 
             //Apply the projection to the feature representing Shanghai because it on the projected layer.  
             offsetProj.Open();  
             PointShape Shanghai_Point = new PointShape(offsetProj.ConvertToExternalProjection(121.78, 31.01));  
             offsetProj.Close();  
 
             Feature Shanghai_feature = new Feature(Shanghai_Point);  
             Shanghai_feature.ColumnValues.Add("LabelName", "Shanghai");  
             cityPoints.InternalFeatures.Add("Shanghai", Shanghai_feature);  
 
             //InMemoryFeatureLayer for the Great Circle.  
             InMemoryFeatureLayer GreatCircle = new InMemoryFeatureLayer();  
             GreatCircle.ZoomLevelSet.ZoomLevel01.DefaultLineStyle = LineStyles.CreateSimpleLineStyle(GeoColor.SimpleColors.Red, 3, true);  
             GreatCircle.ZoomLevelSet.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.Level20;  
             mapEngine.DynamicLayers.Add("Great Circle", GreatCircle);  
 
             //The great circle requires to have the part being in the eastern hemisphere to be offset 360 to the left  
             // so that it display on the projected layer.  
             MultilineShape greatCircleMultiLineShape = GetGreatCircle(LA_Point, Shanghai_Point, offsetProj);  
             Feature GreatCirclefeature = new Feature(greatCircleMultiLineShape);  
             GreatCircle.InternalFeatures.Add("Great Circle", GreatCirclefeature);  
 
             //Notice that the upper left of the current extent has to be expressed in the projected values to have the map  
             //centered on the Pacific.  
             RectangleShape extentRectangleShape = new RectangleShape(new PointShape(offsetProj.ConvertToExternalProjection(80, 58)), new PointShape(-70, -20));  
             mapEngine.CurrentExtent = ExtentHelper.GetDrawingExtent(extentRectangleShape, Map.Width, Map.Height);  
 
             DrawImage();  
         }  
 
         private MultilineShape GetGreatCircle(PointShape pointShape1, PointShape pointShape2, OffsetProjection offsetProj)  
         {  
             offsetProj.Open();  
             if (pointShape1.X < -180)  
             {  
                 pointShape1 = new PointShape(offsetProj.ConvertToInternalProjection(pointShape1.X, pointShape1.Y));  
             }  
             if (pointShape2.X < -180)  
             {  
                 pointShape2 = new PointShape(offsetProj.ConvertToInternalProjection(pointShape2.X, pointShape2.Y));  
             }  
 
             MultilineShape greatCircleMultiLineShape = pointShape1.GetShortestLineTo(pointShape2, GeographyUnit.DecimalDegree);  
 
             MultilineShape resultGreatMultiLineShape = new MultilineShape();  
             foreach (LineShape lineShape in greatCircleMultiLineShape.Lines)  
             {  
                 if (lineShape.Vertices[0].X < 0)  
                 {  
                     resultGreatMultiLineShape.Lines.Add(lineShape);  
                 }  
                 else  
                 {  
                     LineShape resultLineShape = new LineShape();  
                     foreach (Vertex vertex in lineShape.Vertices)  
                     {  
                         Vertex projVertex = offsetProj.ConvertToExternalProjection(vertex.X, vertex.Y);  
                         resultLineShape.Vertices.Add(projVertex);  
                     }  
                     resultGreatMultiLineShape.Lines.Add(resultLineShape);  
                 }  
             }  
 
             return resultGreatMultiLineShape;  
         }  
 
 
 
         private void DrawImage()  
         {  
             if (bitmap != null) { bitmap.Dispose(); }  
             bitmap = new Bitmap(Map.Width, Map.Height);  
             mapEngine.OpenAllLayers();  
             mapEngine.DrawStaticLayers(bitmap, GeographyUnit.DecimalDegree);  
             mapEngine.DrawDynamicLayers(bitmap, GeographyUnit.DecimalDegree);  
             mapEngine.CloseAllLayers();  
 
             Map.Image = bitmap;  
         }  
 
         private void ToolBar_ButtonClick(object sender, ToolBarButtonClickEventArgs e)  
         {  
             switch (e.Button.Tag.ToString())  
             {  
                 case "Zoom In":  
                     mapEngine.CurrentExtent.ScaleDown(50);  
                     break;  
                 case "Zoom Out":  
                     mapEngine.CurrentExtent.ScaleUp(50);  
                     break;  
                 case "Full Extent":  
                     mapEngine.CurrentExtent = ExtentHelper.GetDrawingExtent(new RectangleShape(-180.0, 83.0, 180.0, -90.0), Map.Width, Map.Height);  
                     break;  
                 case "Pan Left":  
                     mapEngine.CurrentExtent = ExtentHelper.Pan(mapEngine.CurrentExtent, PanDirection.Left, 20);  
                     break;  
                 case "Pan Right":  
                     mapEngine.CurrentExtent = ExtentHelper.Pan(mapEngine.CurrentExtent, PanDirection.Right, 20);  
                     break;  
                 case "Pan Up":  
                     mapEngine.CurrentExtent = ExtentHelper.Pan(mapEngine.CurrentExtent, PanDirection.Up, 20);  
                     break;  
                 case "Pan Down":  
                     mapEngine.CurrentExtent = ExtentHelper.Pan(mapEngine.CurrentExtent, PanDirection.Down, 20);  
                     break;  
                 default:  
                     break;  
             }  
             DrawImage();  
         }  
 
         private void btnClose_Click(object sender, EventArgs e)  
         {  
             this.Close();  
         }  
 
         private void Map_MouseMove(object sender, MouseEventArgs e)  
         {  
             //Displays the X and Y in screen coordinates.  
             statusStrip1.Items["toolStripStatusLabelScreen"].Text = "X:" + e.X + " Y:" + e.Y;  
 
             //Gets the PointShape in world coordinates from screen coordinates.  
             PointShape pointShape = ExtentHelper.ToWorldCoordinate(mapEngine.CurrentExtent, new ScreenPointF(e.X, e.Y), Map.Width, Map.Height);  
 
             //Displays world coordinates.  
             statusStrip1.Items["toolStripStatusLabelWorld"].Text = "(world) X:" + Math.Round(pointShape.X, 4) + " Y:" + Math.Round(pointShape.Y, 4);  
         }  
 
 
     }  
 }