public GeoPoint GetGeoPoint(PointD pixPoint)
{
// get a bearing to the point from our known point
if ((pixPoint.X == this.PixPoint.X) && (pixPoint.Y == this.PixPoint.Y))
{
return(this.GeoPoint);
}
/** draw a line to get our pixel length */
Line l1 = new Line(pixPoint, this.PixPoint);
PointD vectorPoint = new PointD(_pixelReferencePoint.X + 100, _pixelReferencePoint.Y);
double pixBearing = FlatGeo.Angle(pixPoint, _pixelReferencePoint, vectorPoint).Degrees + 90;
double pixDistance = l1.Length;
double geoBearing = FlatGeo.Radians((pixBearing + this.BearingDelta) % 360);
double geoDistance = pixDistance / this.PixelsPerMeter;
double lat = FlatGeo.Radians(this.GeoPoint.Y);
double lon = FlatGeo.Radians(this.GeoPoint.X);
double ddr = geoDistance / EarthGeo.EarthRadius;
double lat2 = Math.Asin(Math.Sin(lat) * Math.Cos(ddr) + Math.Cos(lat) * Math.Sin(ddr) * Math.Cos(geoBearing));
double lon2 = lon + Math.Atan2(Math.Sin(geoBearing) * Math.Sin(ddr) * Math.Cos(lat), Math.Cos(ddr) - Math.Sin(lat) * Math.Sin(lat2));
lon2 = ((lon2 + Math.PI) % (2 * Math.PI)) - Math.PI;
lat2 = FlatGeo.Degrees(lat2);
lon2 = FlatGeo.Degrees(lon2);
return(new GeoPoint(lat2, lon2));
}
public PointD GetPixelPoint(GeoPoint geoPoint)
{
// get a bearing to the point from our known point
double geoBearing = EarthGeo.GetBearing(this.GeoPoint, geoPoint);
double geoDistance = EarthGeo.GetDistance(this.GeoPoint, geoPoint);
double pixBearing = FlatGeo.Radians(((geoBearing + 360) - this.BearingDelta) % 360);
double pixDistance = geoDistance * this.PixelsPerMeter;
PointD ret = new PointD(this.PixPoint.X + (Math.Sin(pixBearing) * pixDistance), this.PixPoint.Y - (Math.Cos(pixBearing) * pixDistance));
return(ret);
}
public static double GetBearing(GeoPoint pt1, GeoPoint pt2)
{
double lat1 = FlatGeo.Radians(pt1.Y);
double lon1 = FlatGeo.Radians(pt1.X);
double lat2 = FlatGeo.Radians(pt2.Y);
double lon2 = FlatGeo.Radians(pt2.X);
double y = Math.Sin(lon2 - lon1) * Math.Cos(lat2);
double x = Math.Cos(lat1) * Math.Sin(lat2) - Math.Sin(lat1) * Math.Cos(lat2) * Math.Cos(lon2 - lon1);
double bearing = Math.Atan2(y, x); // bearing in radians
double ret = (FlatGeo.Degrees(bearing) + 360) % 360;
return(ret);
}
static public double GetDistance(GeoPoint pt1, GeoPoint pt2)
{
// get the arc between the two earth points in radians
double deltaLat = FlatGeo.Radians(pt2.Y - pt1.Y);
double deltaLong = FlatGeo.Radians(pt2.X - pt1.X);
double latitudeHelix = Math.Pow(Math.Sin(deltaLat * 0.5), 2);
double longitudeHelix = Math.Pow(Math.Sin(deltaLong * 0.5), 2);
double tmp = Math.Cos(FlatGeo.Radians(pt1.Y)) * Math.Cos(FlatGeo.Radians(pt2.Y));
double rad = 2.0 * Math.Asin(Math.Sqrt(latitudeHelix + tmp * longitudeHelix));
// Multiply the radians by the earth radius in meters for a distance measurement in meters
return(EarthRadius * rad);
}
public static GeoPoint GetPoint(GeoPoint origin, Double bearing, Double distanceInMeters)
{
bearing = FlatGeo.Radians(bearing % 360);
double ddr = distanceInMeters / EarthGeo.EarthRadius;
double lat = FlatGeo.Radians(origin.Y);
double lon = FlatGeo.Radians(origin.X);
double lat2 = Math.Asin(Math.Sin(lat) * Math.Cos(ddr) + Math.Cos(lat) * Math.Sin(ddr) * Math.Cos(bearing));
double lon2 = lon + Math.Atan2(Math.Sin(bearing) * Math.Sin(ddr) * Math.Cos(lat), Math.Cos(ddr) - Math.Sin(lat) * Math.Sin(lat2));
lon2 = ((lon2 + Math.PI) % (2 * Math.PI)) - Math.PI;
return(new GeoPoint(FlatGeo.Degrees(lat2), FlatGeo.Degrees(lon2)));
}