Add decimal degrees (DD) and degrees minutes seconds (DMS) converters

Author: BobLd

OxyPlot.Core.Cartography.Tests/CartographyHelperTest.cs

@@ -0,0 +1,35 @@
+namespace OxyPlot.Core.Cartography.Tests
+{
+    public class CartographyHelperTest
+    {
+        [Fact]
+        public void DecimalDegreesToDegreesMinutesSecondsTest()
+        {
+            var dms = CartographyHelper.DecimalDegreesToDegreesMinutesSeconds(38.8897, true, 0);
+            Assert.Equal("38\u00b053\u203223\u2033N", dms);
+
+            var dms1 = CartographyHelper.DecimalDegreesToDegreesMinutesSeconds(-77.0089, false, 0);
+            Assert.Equal("77\u00b000\u203232\u2033W", dms1);
+        }
+
+        [Fact]
+        public void DegreesMinutesSecondsToDecimalDegreesTests()
+        {
+            var dec = CartographyHelper.DegreesMinutesSecondsToDecimalDegrees(38, 53, 23, 'N');
+            Assert.Equal(38.8897, dec, 4);
+
+            var dec1 = CartographyHelper.DegreesMinutesSecondsToDecimalDegrees(77, 0, 32, 'W');
+            Assert.Equal(-77.0089, dec1, 4);
+        }
+
+        [Fact]
+        public void DegreesMinutesSecondsToDecimalDegreesTests2()
+        {
+            var dec = CartographyHelper.DegreesMinutesSecondsToDecimalDegrees("38\u00b053\u203223\u2033N");
+            Assert.Equal(38.8897, dec, 4);
+
+            var dec1 = CartographyHelper.DegreesMinutesSecondsToDecimalDegrees("77\u00b000\u203232\u2033W");
+            Assert.Equal(-77.0089, dec1, 4);
+        }
+    }
+}

OxyPlot.Core.Cartography.Tests/OxyPlot.Core.Cartography.Tests.csproj

@@ -21,4 +21,8 @@
     </PackageReference>
   </ItemGroup>
 
+  <ItemGroup>
+    <ProjectReference Include="..\OxyPlot.Core.Cartography\OxyPlot.Core.Cartography.csproj" />
+  </ItemGroup>
+
 </Project>

OxyPlot.Core.Cartography.Tests/UnitTest1.cs

@@ -30,6 +30,7 @@ public LatitudeWebMercatorAxis()
             AbsoluteMinimum = -_maxValue;
             AbsoluteMaximum = _maxValue;
             Key = "Latitude";
+            StringFormat = "00.0###°";
 
             // Hack as 'UpdateActualMaxMin' method is internal
             _updateActualMaxMinMethod = typeof(Axis).GetMethod("UpdateActualMaxMin",

OxyPlot.Core.Cartography/Axes/LatitudeWebMercatorAxis.cs

@@ -15,6 +15,7 @@ public LongitudeAxis() : base()
             this.AbsoluteMinimum = -_maxDefaultValue;
             this.AbsoluteMaximum = _maxDefaultValue;
             Key = "Longitude";
+            StringFormat = "00.0###°";
         }
 
         /// <summary>

OxyPlot.Core.Cartography/Axes/LongitudeAxis.cs

@@ -81,6 +81,106 @@ public static void TileToLatLon(double x, double y, int zoom, out double latitud
             latitude = lat * 180.0 / Math.PI;
         }
 
+        /// <summary>
+        /// Converts decimal degrees (DD) to degrees minutes seconds coordinates (DMS).
+        /// <para>
+        /// <see href="https://en.wikipedia.org/wiki/Decimal_degrees"/>
+        /// </para>
+        /// <see href="https://en.wikipedia.org/wiki/ISO_6709#Representation_at_the_human_interface_(Annex_D)"/>
+        /// </summary>
+        /// <param name="decimalDegrees">The decimal degrees (DD) coordinate</param>
+        /// <param name="isLatitude">True if latitude, false if longitude</param>
+        /// <param name="secondsDecimal">Decimal roundings of seconds part</param>
+        /// <returns>The degrees minutes seconds coordinates (DMS), e.g. 50°40′46.461″N</returns>
+        public static string DecimalDegreesToDegreesMinutesSeconds(double decimalDegrees, bool isLatitude, int secondsDecimal)
+        {
+            // see https://en.wikipedia.org/wiki/ISO_6709#Representation_at_the_human_interface_(Annex_D)
+            var card = isLatitude ? (decimalDegrees > 0 ? "N" : "S") : (decimalDegrees > 0 ? "E" : "W");
+            var d = Math.Truncate(decimalDegrees);
+            var delta = Math.Abs(decimalDegrees - d);
+            var m = Math.Truncate(60 * delta);
+            var s = Math.Round(3600.0 * delta - 60.0 * m, secondsDecimal);
+            return $"{Math.Abs(d):00}\u00b0{m:00}\u2032{s:00}\u2033{card}";
+        }
+
+        /// <summary>
+        /// Converts degrees minutes seconds (DMS) to decimal degrees (DD) coordinates.
+        /// <para>
+        /// <see href="https://en.wikipedia.org/wiki/Decimal_degrees"/>
+        /// </para>
+        /// <see href="https://en.wikipedia.org/wiki/ISO_6709#Representation_at_the_human_interface_(Annex_D)"/>
+        /// </summary>
+        /// <param name="degrees"></param>
+        /// <param name="minutes"></param>
+        /// <param name="seconds"></param>
+        /// <param name="cardinal"></param>
+        /// <returns>The decimal degrees (DD) coordinates</returns>
+        /// <exception cref="ArgumentException"></exception>
+        public static double DegreesMinutesSecondsToDecimalDegrees(int degrees, int minutes, double seconds, char cardinal)
+        {
+            double sign;
+            if (cardinal.Equals('N') || cardinal.Equals('E'))
+            {
+                sign = 1;
+            }
+            else if (cardinal.Equals('S') || cardinal.Equals('W'))
+            {
+                sign = -1;
+            }
+            else
+            {
+                throw new ArgumentException($"Cardinal value should be either 'N', 'S', 'E' or 'W', but is '{cardinal}'", nameof(cardinal));
+            }
+
+            return (degrees + minutes / 60.0 + seconds / 3600.0) * sign;
+        }
+
+        /// <summary>
+        /// Converts degrees minutes seconds (DMS) to decimal degrees (DD) coordinates.
+        /// <para>
+        /// <see href="https://en.wikipedia.org/wiki/Decimal_degrees"/>
+        /// </para>
+        /// <see href="https://en.wikipedia.org/wiki/ISO_6709#Representation_at_the_human_interface_(Annex_D)"/>
+        /// </summary>
+        /// <param name="degreesMinutesSeconds">
+        /// The degrees minutes seconds coordinate, formated as DD°MM′SS.SSS″C e.g. 38°53′23″N
+        /// <para>
+        /// ° = \u00b0, ′ = \u2032, ″ = \u2033
+        /// </para>
+        /// </param>
+        /// <returns>The decimal degrees (DD) coordinates</returns>
+        public static double DegreesMinutesSecondsToDecimalDegrees(string degreesMinutesSeconds)
+        {
+            var parts = degreesMinutesSeconds.Split('\u00b0', '\u2032', '\u2033');
+            if (parts.Length != 4)
+            {
+                throw new ArgumentException("The coordinate should be in DMS format, i.e. DD°MM′SS.SSS″C", nameof(degreesMinutesSeconds));
+            }
+
+            if (!int.TryParse(parts[0], out int d))
+            {
+                throw new ArgumentException($"Could not parse degrees part, got {parts[0]}. The coordinate should be in DMS format, i.e. DD°MM′SS.SSS″C", nameof(degreesMinutesSeconds));
+            }
+
+            if (!int.TryParse(parts[1], out int m))
+            {
+                throw new ArgumentException($"Could not parse minutes part, got {parts[1]}. The coordinate should be in DMS format, i.e. DD°MM′SS.SSS″C", nameof(degreesMinutesSeconds));
+            }
+
+            if (!double.TryParse(parts[2], out double s))
+            {
+                throw new ArgumentException($"Could not parse seconds part, got {parts[2]}. The coordinate should be in DMS format, i.e. DD°MM′SS.SSS″C", nameof(degreesMinutesSeconds));
+            }
+
+            var card = parts[3];
+            if (card.Length != 1)
+            {
+                throw new ArgumentException($"Could not parse cardinal part, got {parts[3]}. The coordinate should be in DMS format, i.e. DD°MM′SS.SSS″C", nameof(degreesMinutesSeconds));
+            }
+
+            return DegreesMinutesSecondsToDecimalDegrees(d, m, s, card[0]);
+        }
+
         /// <summary>
         /// Generate the storage path from a uri.
         /// </summary>

OxyPlot.Core.Cartography/Utilities/CartographyHelper.cs

@@ -63,13 +63,13 @@ private PlotModel CreateMapPlotView()
                 Position = AxisPosition.Left,
                 Minimum = 51.42,
                 Maximum = 51.62,
-                Title = "Latitude"
+                Title = "Latitude",
             });
 
             var tileMapImageProvider = new HttpTileMapImageProvider(SynchronizationContext.Current)
             {
-                //Url = "http://tile.openstreetmap.org/{Z}/{X}/{Y}.png",
-                Url = "https://server.arcgisonline.com/arcgis/rest/services/World_Imagery/MapServer/tile/{Z}/{Y}/{X}", // https://developers.arcgis.com/documentation/mapping-apis-and-services/data-hosting/services/image-tile-service/
+                Url = "http://tile.openstreetmap.org/{Z}/{X}/{Y}.png",
+                //Url = "https://server.arcgisonline.com/arcgis/rest/services/World_Imagery/MapServer/tile/{Z}/{Y}/{X}", // https://developers.arcgis.com/documentation/mapping-apis-and-services/data-hosting/services/image-tile-service/
                 //Url = "https://maptiles.finncdn.no/tileService/1.0.3/norortho/{Z}/{X}/{Y}.png",
                 //Url = "https://maptiles.finncdn.no/tileService/1.0.3/normap/{Z}/{X}/{Y}.png",
 
@@ -116,7 +116,7 @@ private PlotModel CreateMapPlotView()
                 // Add the tile map annotation
                 model.Annotations.Add(new MapTileAnnotation(streamImg, tileMapImageProvider)
                 {
-                    CopyrightNotice = "OpenStreetMap",
+                    CopyrightNotice = "© OpenStreetMap contributors",
                     MinZoomLevel = 0,
                     MaxZoomLevel = 19, // max OpenStreetMap value
                     IsTileGridVisible = true,