PlateCarreeProjectionDarbAe.cs


namespace GMap.NET.Projections
{
   using System;

   /// <summary>
   /// Plate Carrée (literally, “plane square”) projection
   /// PROJCS["WGS 84 / World Equidistant Cylindrical",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],UNIT["Meter",1]]
   /// 
   ///"spatialReference": 
   ///{"wkid":4326},"singleFusedMapCache":true,"tileInfo":  
   ///{"rows":256,"cols":256,"dpi":96,"format":"PNG8","compressionQuality":0,   
   ///"origin":{"x":-400,"y":400},"spatialReference":{"wkid":4326},"lods": 
   ///
   ///[{"level":0,"resolution":0.0118973050291514,"scale":5000000},
   ///{"level":1,"resolution":0.0059486525145757,"scale":2500000}, 
   ///{"level":2,"resolution":0.00297432625728785,"scale":1250000}, 
   ///{"level":3,"resolution":0.00118973050291514,"scale":500000}, 
   ///{"level":4,"resolution":0.00059486525145757,"scale":250000}, 
   ///{"level":5,"resolution":0.000356919150874542,"scale":150000},
   ///{"level":6,"resolution":0.000178459575437271,"scale":75000}, 
   ///{"level":7,"resolution":0.000118973050291514,"scale":50000}, 
   ///{"level":8,"resolution":5.9486525145757E-05,"scale":25000},
   ///{"level":9,"resolution":3.56919150874542E-05,"scale":15000},
   ///{"level":10,"resolution":1.90356880466422E-05,"scale":8000}, 
   ///{"level":11,"resolution":9.51784402332112E-06,"scale":4000}, 
   ///{"level":12,"resolution":4.75892201166056E-06,"scale":2000}]},
   ///
   ///"initialExtent":    
   ///{"xmin":42.1125196069871,"ymin":18.6650706214551,"xmax":65.698643558112 
   ///4,"ymax":29.4472987133981,"spatialReference":{"wkid":4326}},
   ///
   ///"fullExtent":   
   ///{"xmin":41.522866508209,"ymin":18.7071563263201,"xmax":66.2882966568906 
   ///,"ymax":29.4052130085331,"spatialReference":{"wkid":4326}},
   ///
   ///"units":"esriDecimalDegrees"
   /// </summary>
   public class PlateCarreeProjectionDarbAe : PureProjection
   {
      public static readonly PlateCarreeProjectionDarbAe Instance = new PlateCarreeProjectionDarbAe();

      public static readonly double MinLatitude = 18.7071563263201;
      public static readonly double MaxLatitude = 29.4052130085331;
      public static readonly double MinLongitude = 41.522866508209;
      public static readonly double MaxLongitude = 66.2882966568906;

      static readonly double orignX = -400;
      static readonly double orignY = 400;

      public override RectLatLng Bounds
      {
         get
         {
            return RectLatLng.FromLTRB(MinLongitude, MaxLatitude, MaxLongitude, MinLatitude);
         }
      }

      GSize tileSize = new GSize(256, 256);
      public override GSize TileSize
      {
         get
         {
            return tileSize;
         }
      }

      public override double Axis
      {
         get
         {
            return 6378137;
         }
      }

      public override double Flattening
      {
         get
         {
            return (1.0 / 298.257223563);
         }
      }

      public override GPoint FromLatLngToPixel(double lat, double lng, int zoom)
      {
         GPoint ret = GPoint.Empty;

         lat = Clip(lat, MinLatitude, MaxLatitude);
         lng = Clip(lng, MinLongitude, MaxLongitude);

         /*
           getContainingTileCoords:function(ti,_1dd,lod)
           {
             var to=ti.origin,
             res=lod.resolution,
             tmw=ti.width*res,
             tmh=ti.height*res,
             tc=Math.floor((_1dd.x-to.x)/tmw),
             tr=Math.floor((to.y-_1dd.y)/tmh);
           }
         */

         double res = GetTileMatrixResolution(zoom);

         ret.X = (long)Math.Floor((lng - orignX) / res);
         ret.Y = (long)Math.Floor((orignY - lat) / res);

         return ret;
      }

      public override PointLatLng FromPixelToLatLng(long x, long y, int zoom)
      {
         PointLatLng ret = PointLatLng.Empty;

         double res = GetTileMatrixResolution(zoom);

         ret.Lat = orignY - (y * res);
         ret.Lng = (x * res) + orignX;

         return ret;
      }

      public static double GetTileMatrixResolution(int zoom)
      {
         double ret = 0;

         switch(zoom)
         {
            #region -- sizes --
            case 0:
            {
               ret = 0.0118973050291514;
            }
            break;

            case 1:
            {
               ret = 0.0059486525145757;
            }
            break;

            case 2:
            {
               ret = 0.00297432625728785;
            }
            break;

            case 3:
            {
               ret = 0.00118973050291514;
            }
            break;

            case 4:
            {
               ret = 0.00059486525145757;
            }
            break;

            case 5:
            {
               ret = 0.000356919150874542;
            }
            break;

            case 6:
            {
               ret = 0.000178459575437271;
            }
            break;

            case 7:
            {
               ret = 0.000118973050291514;
            }
            break;

            case 8:
            {
               ret = 5.9486525145757E-05;
            }
            break;

            case 9:
            {
               ret = 3.56919150874542E-05;
            }
            break;

            case 10:
            {
               ret = 1.90356880466422E-05;
            }
            break;

            case 11:
            {
               ret = 9.51784402332112E-06;
            }
            break;

            case 12:
            {
               ret = 4.75892201166056E-06;
            }
            break;
            #endregion
         }

         return ret;
      }

      public override double GetGroundResolution(int zoom, double latitude)
      {
         return GetTileMatrixResolution(zoom);
      }

      public override GSize GetTileMatrixMaxXY(int zoom)
      {
         var maxPx = FromLatLngToPixel(MinLatitude, MaxLongitude, zoom);
         return new GSize(FromPixelToTileXY(maxPx));
      }

      public override GSize GetTileMatrixMinXY(int zoom)
      {
         var minPx = FromLatLngToPixel(MaxLatitude, MinLongitude, zoom);
         return new GSize(FromPixelToTileXY(minPx));
      }
   }
}