diff --git a/MapControl/Shared/MapBase.cs b/MapControl/Shared/MapBase.cs
index e0afa23d..36c790bd 100644
--- a/MapControl/Shared/MapBase.cs
+++ b/MapControl/Shared/MapBase.cs
@@ -202,7 +202,7 @@ namespace MapControl
///
public Matrix GetMapTransform(Location location)
{
- var mapScale = GetMapScale(location);
+ var mapScale = GetMapScale(location.Latitude, location.Longitude);
var transform = new Matrix(mapScale.X, 0d, 0d, mapScale.Y, 0d, 0d);
transform.Rotate(ViewTransform.Rotation);
diff --git a/MapControl/Shared/MapProjectionFactory.cs b/MapControl/Shared/MapProjectionFactory.cs
index 7c43093c..5881c620 100644
--- a/MapControl/Shared/MapProjectionFactory.cs
+++ b/MapControl/Shared/MapProjectionFactory.cs
@@ -24,12 +24,12 @@ namespace MapControl
projection = new EquirectangularProjection(crsId);
break;
- case UpsNorthProjection.DefaultCrsId:
- projection = new UpsNorthProjection();
+ case Wgs84UpsNorthProjection.DefaultCrsId:
+ projection = new Wgs84UpsNorthProjection();
break;
- case UpsSouthProjection.DefaultCrsId:
- projection = new UpsSouthProjection();
+ case Wgs84UpsSouthProjection.DefaultCrsId:
+ projection = new Wgs84UpsSouthProjection();
break;
case Wgs84AutoUtmProjection.DefaultCrsId:
diff --git a/MapControl/Shared/PolarStereographicProjection.cs b/MapControl/Shared/PolarStereographicProjection.cs
index 2b7e06d7..8e35483a 100644
--- a/MapControl/Shared/PolarStereographicProjection.cs
+++ b/MapControl/Shared/PolarStereographicProjection.cs
@@ -26,70 +26,57 @@ namespace MapControl
public double FalseNorthing { get; set; } = 2e6;
public Hemisphere Hemisphere { get; set; }
- public override Point RelativeScale(double latitude, double longitude)
+ public static double RelativeScale(Hemisphere hemisphere, double equatorialRadius, double flattening, double scaleFactor, double latitude)
{
- var phi = latitude * Math.PI / 180d;
+ var sign = hemisphere == Hemisphere.North ? 1d : -1d;
+ var phi = sign * latitude * Math.PI / 180d;
- if (Hemisphere == Hemisphere.South)
- {
- phi = -phi;
- }
-
- var e = Math.Sqrt((2d - Flattening) * Flattening);
+ var e = Math.Sqrt((2d - flattening) * flattening);
var eSinPhi = e * Math.Sin(phi);
var t = Math.Tan(Math.PI / 4d - phi / 2d)
/ Math.Pow((1d - eSinPhi) / (1d + eSinPhi), e / 2d); // p.161 (15-9)
- var r = 2d * EquatorialRadius * ScaleFactor * t
+ var r = 2d * equatorialRadius * scaleFactor * t
/ Math.Sqrt(Math.Pow(1d + e, 1d + e) * Math.Pow(1d - e, 1d - e)); // p.161 (21-33)
var m = Math.Cos(phi) / Math.Sqrt(1d - eSinPhi * eSinPhi); // p.160 (14-15)
- var k = r / (EquatorialRadius * m); // p.161 (21-32)
+
+ return r / (equatorialRadius * m); // p.161 (21-32)
+ }
+
+ public override Point RelativeScale(double latitude, double longitude)
+ {
+ var k = RelativeScale(Hemisphere, EquatorialRadius, Flattening, ScaleFactor, latitude);
return new Point(k, k);
}
public override Point? LocationToMap(double latitude, double longitude)
{
- var phi = latitude * Math.PI / 180d;
- var lambda = longitude * Math.PI / 180d;
-
- if (Hemisphere == Hemisphere.South)
- {
- phi = -phi;
- lambda = -lambda;
- }
+ var sign = Hemisphere == Hemisphere.North ? 1d : -1d;
+ var phi = sign * latitude * Math.PI / 180d;
+ var lambda = sign * longitude * Math.PI / 180d;
var e = Math.Sqrt((2d - Flattening) * Flattening);
var eSinPhi = e * Math.Sin(phi);
var t = Math.Tan(Math.PI / 4d - phi / 2d)
/ Math.Pow((1d - eSinPhi) / (1d + eSinPhi), e / 2d); // p.161 (15-9)
+
var r = 2d * EquatorialRadius * ScaleFactor * t
/ Math.Sqrt(Math.Pow(1d + e, 1d + e) * Math.Pow(1d - e, 1d - e)); // p.161 (21-33)
- var x = r * Math.Sin(lambda); // p.161 (21-30)
- var y = -r * Math.Cos(lambda); // p.161 (21-31)
-
- if (Hemisphere == Hemisphere.South)
- {
- x = -x;
- y = -y;
- }
+ var x = sign * r * Math.Sin(lambda); // p.161 (21-30)
+ var y = sign * -r * Math.Cos(lambda); // p.161 (21-31)
return new Point(x + FalseEasting, y + FalseNorthing);
}
public override Location MapToLocation(double x, double y)
{
- x -= FalseEasting;
- y -= FalseNorthing;
-
- if (Hemisphere == Hemisphere.South)
- {
- x = -x;
- y = -y;
- }
+ var sign = Hemisphere == Hemisphere.North ? 1d : -1d;
+ x = sign * (x - FalseEasting);
+ y = sign * (y - FalseNorthing);
var e = Math.Sqrt((2d - Flattening) * Flattening);
var r = Math.Sqrt(x * x + y * y); // p.162 (20-18)
@@ -99,29 +86,23 @@ namespace MapControl
var phi = WorldMercatorProjection.ApproximateLatitude(e, t); // p.162 (3-5)
var lambda = Math.Atan2(x, -y); // p.162 (20-16)
- if (Hemisphere == Hemisphere.South)
- {
- phi = -phi;
- lambda = -lambda;
- }
-
- return new Location(phi * 180d / Math.PI, lambda * 180d / Math.PI);
+ return new Location(sign * phi * 180d / Math.PI, sign * lambda * 180d / Math.PI);
}
}
///
/// Universal Polar Stereographic North Projection - EPSG:32661.
///
- public class UpsNorthProjection : PolarStereographicProjection
+ public class Wgs84UpsNorthProjection : PolarStereographicProjection
{
public const string DefaultCrsId = "EPSG:32661";
- public UpsNorthProjection() // parameterless constructor for XAML
+ public Wgs84UpsNorthProjection() // parameterless constructor for XAML
: this(DefaultCrsId)
{
}
- public UpsNorthProjection(string crsId)
+ public Wgs84UpsNorthProjection(string crsId)
{
CrsId = crsId;
Hemisphere = Hemisphere.North;
@@ -131,16 +112,16 @@ namespace MapControl
///
/// Universal Polar Stereographic South Projection - EPSG:32761.
///
- public class UpsSouthProjection : PolarStereographicProjection
+ public class Wgs84UpsSouthProjection : PolarStereographicProjection
{
public const string DefaultCrsId = "EPSG:32761";
- public UpsSouthProjection() // parameterless constructor for XAML
+ public Wgs84UpsSouthProjection() // parameterless constructor for XAML
: this(DefaultCrsId)
{
}
- public UpsSouthProjection(string crsId)
+ public Wgs84UpsSouthProjection(string crsId)
{
CrsId = crsId;
Hemisphere = Hemisphere.South;
diff --git a/MapControl/Shared/WorldMercatorProjection.cs b/MapControl/Shared/WorldMercatorProjection.cs
index 4f0c245d..b2f1cf2f 100644
--- a/MapControl/Shared/WorldMercatorProjection.cs
+++ b/MapControl/Shared/WorldMercatorProjection.cs
@@ -30,7 +30,7 @@ namespace MapControl
public override Point RelativeScale(double latitude, double longitude)
{
- var k = ScaleFactor(latitude);
+ var k = RelativeScale(latitude);
return new Point(k, k);
}
@@ -49,7 +49,7 @@ namespace MapControl
x / Wgs84MeterPerDegree);
}
- public static double ScaleFactor(double latitude)
+ public static double RelativeScale(double latitude)
{
var phi = latitude * Math.PI / 180d;
var eSinPhi = Wgs84Eccentricity * Math.Sin(phi);