From cc690c54459c3c6a7b33f3fabcc3df99a7c2a266 Mon Sep 17 00:00:00 2001
From: ClemensF <Clemens@T400.(none)>
Date: Sun, 6 May 2012 11:28:47 +0200
Subject: [PATCH] Added Location.NormalizeLongitude and fixed LocationAnimation

---
 MapControl/Location.cs          | 25 +++++++++++++++++++++----
 MapControl/LocationAnimation.cs |  4 +++-
 MapControl/Map.cs               |  2 +-
 MapControl/MapGraticule.cs      |  2 +-
 4 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/MapControl/Location.cs b/MapControl/Location.cs
index ed2ccb56..7035698d 100644
--- a/MapControl/Location.cs
+++ b/MapControl/Location.cs
@@ -11,6 +11,9 @@ namespace MapControl
     [TypeConverter(typeof(LocationConverter))]
     public class Location
     {
+        private double latitude;
+        private double longitude;
+
         public Location()
         {
         }
@@ -21,8 +24,22 @@ namespace MapControl
             Longitude = longitude;
         }
 
-        public double Latitude { get; set; }
-        public double Longitude { get; set; }
+        public double Latitude
+        {
+            get { return latitude; }
+            set { latitude = Math.Min(Math.Max(value, -90d), 90d); }
+        }
+
+        public double Longitude
+        {
+            get { return longitude; }
+            set { longitude = value; }
+        }
+
+        public override string ToString()
+        {
+            return string.Format(CultureInfo.InvariantCulture, "{0:0.00000},{1:0.00000}", latitude, longitude);
+        }
 
         public static Location Parse(string source)
         {
@@ -30,9 +47,9 @@ namespace MapControl
             return new Location(p.X, p.Y);
         }
 
-        public override string ToString()
+        public static double NormalizeLongitude(double longitude)
         {
-            return string.Format(CultureInfo.InvariantCulture, "{0:0.00000},{1:0.00000}", Latitude, Longitude);
+            return ((longitude + 180d) % 360d + 360d) % 360d - 180d;
         }
     }
 
diff --git a/MapControl/LocationAnimation.cs b/MapControl/LocationAnimation.cs
index 9f7178e4..83642e7a 100644
--- a/MapControl/LocationAnimation.cs
+++ b/MapControl/LocationAnimation.cs
@@ -42,9 +42,11 @@ namespace MapControl
                 progress = EasingFunction.Ease(progress);
             }
 
+            double deltaLongitude = progress * Location.NormalizeLongitude(To.Longitude - From.Longitude);
+
             return new Location(
                 (1d - progress) * From.Latitude + progress * To.Latitude,
-                (1d - progress) * From.Longitude + progress * To.Longitude);
+                Location.NormalizeLongitude(From.Longitude + deltaLongitude));
         }
     }
 }
diff --git a/MapControl/Map.cs b/MapControl/Map.cs
index e9339e20..f2832dab 100644
--- a/MapControl/Map.cs
+++ b/MapControl/Map.cs
@@ -574,7 +574,7 @@ namespace MapControl
         private Location CoerceCenter(Location location)
         {
             location.Latitude = Math.Min(Math.Max(location.Latitude, -MapTransform.MaxLatitude), MapTransform.MaxLatitude);
-            location.Longitude = ((location.Longitude + 180d) % 360d + 360d) % 360d - 180d;
+            location.Longitude = Location.NormalizeLongitude(location.Longitude);
             return location;
         }
 
diff --git a/MapControl/MapGraticule.cs b/MapControl/MapGraticule.cs
index 53d5e7f2..8ed45fe4 100644
--- a/MapControl/MapGraticule.cs
+++ b/MapControl/MapGraticule.cs
@@ -177,7 +177,7 @@ namespace MapControl
                             Point latPos = new Point(p.X + t + 2d, p.Y - t - FontSize / 4d);
                             Point lonPos = new Point(p.X + t + 2d, p.Y + t + FontSize);
                             string latString = CoordinateString(lat, format, "NS");
-                            string lonString = CoordinateString(((lon + 180d) % 360d + 360d) % 360d - 180d, format, "EW");
+                            string lonString = CoordinateString(Location.NormalizeLongitude(lon), format, "EW");
 
                             drawingContext.PushTransform(new RotateTransform(parentMap.Heading, p.X, p.Y));
                             drawingContext.DrawGlyphRun(Foreground, GlyphRunText.Create(latString, typeface, FontSize, latPos));