EMMLocationCoordinate2D _EMMCoordinateTransformCGJ02FromBD09(EMMLocationCoordinate2D coordinate)
{
double x = coordinate.longitude - 0.0065, y = coordinate.latitude - 0.006;
double z = Math.Sqrt(x * x + y * y) - 0.00002 * Math.Sin(y * x_pi);
double theta = Math.Atan2(y, x) - 0.000003 * Math.Cos(x * x_pi);
double gg_lon = z * Math.Cos(theta);
double gg_lat = z * Math.Sin(theta);
return(EMMLocationCoordinate2DMake(EMMLocationCoordinateType.CGJ02, gg_lat, gg_lon));
}
EMMLocationCoordinate2D _EMMCoordinateTransformBD09FromCGJ02(EMMLocationCoordinate2D coordinate)
{
double x = coordinate.longitude, y = coordinate.latitude;
double z = Math.Sqrt(x * x + y * y) + 0.00002 * Math.Sin(y * x_pi);
double theta = Math.Atan2(y, x) + 0.000003 * Math.Cos(x * x_pi);
double bd_lon = z * Math.Cos(theta) + 0.0065;
double bd_lat = z * Math.Sin(theta) + 0.006;
return(EMMLocationCoordinate2DMake(EMMLocationCoordinateType.BD09, bd_lat, bd_lon));
}
EMMLocationCoordinate2D _EMMCoordinateTransformCGJ02FromWGS84(EMMLocationCoordinate2D coordinate)
{
double dLat = emm_transformLat(coordinate.longitude - 105.0, coordinate.latitude - 35.0);
double dLon = emm_transformLon(coordinate.longitude - 105.0, coordinate.latitude - 35.0);
double radLat = coordinate.latitude / 180.0 * pi;
double magic = Math.Sin(radLat);
magic = 1 - ee * magic * magic;
double sqrtMagic = Math.Sqrt(magic);
dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
dLon = (dLon * 180.0) / (a / sqrtMagic * Math.Cos(radLat) * pi);
return(EMMLocationCoordinate2DMake(EMMLocationCoordinateType.CGJ02, coordinate.latitude + dLat, coordinate.longitude + dLon));
}
public EMMLocationCoordinate2D EMMBD09CoordinateTransform(EMMLocationCoordinate2D coordinate)
{
if (coordinate.type == EMMLocationCoordinateType.WGS84)
{
return(_EMMCoordinateTransformBD09FromWGS84(coordinate));
}
else if (coordinate.type == EMMLocationCoordinateType.CGJ02)
{
return(_EMMCoordinateTransformBD09FromCGJ02(coordinate));
}
else if (coordinate.type == EMMLocationCoordinateType.BD09)
{
return(coordinate);
}
return(EMMLocationCoordinate2DMake(0, 0, 0));
}
EMMLocationCoordinate2D _EMMCoordinateTransformWGS84FromBD09(EMMLocationCoordinate2D coordinate)
{
return(_EMMCoordinateTransformWGS84FromCGJ02(_EMMCoordinateTransformCGJ02FromBD09(coordinate)));
}
EMMLocationCoordinate2D _EMMCoordinateTransformWGS84FromCGJ02(EMMLocationCoordinate2D coordinate)
{
return(EMMLocationCoordinate2DMake(EMMLocationCoordinateType.WGS84,
coordinate.latitude - (_EMMCoordinateTransformCGJ02FromWGS84(coordinate).latitude - coordinate.latitude),
coordinate.longitude - (_EMMCoordinateTransformCGJ02FromWGS84(coordinate).longitude - coordinate.longitude)));
}
