/** * \file NETGeographicLib/OSGB.h * \brief Header for NETGeographicLib::OSGB class * * NETGeographicLib is copyright (c) Scott Heiman (2013) * GeographicLib is Copyright (c) Charles Karney (2010-2012) * and licensed under the MIT/X11 License. * For more information, see * https://geographiclib.sourceforge.io/ **********************************************************************/ #pragma once namespace NETGeographicLib { /** * \brief .NET wrapper for GeographicLib::OSGB. * * This class allows .NET applications to access GeographicLib::OSGB. * * The class implements the coordinate system used by the Ordnance Survey for * maps of Great Britain and conversions to the grid reference system. * * See * - * A guide to coordinate systems in Great Britain * - * Guide to the National Grid * * \b WARNING: the latitudes and longitudes for the Ordnance Survey grid * system do not use the WGS84 datum. Do not use the values returned by this * class in the UTMUPS, MGRS, or Geoid classes without first converting the * datum (and vice versa). * * C# Example: * \include example-OSGB.cs * Managed C++ Example: * \include example-OSGB.cpp * Visual Basic Example: * \include example-OSGB.vb **********************************************************************/ public ref class OSGB { private: // hide the constructor since all member are static OSGB(void) {} public: /** * Forward projection, from geographic to OSGB coordinates. * * @param[in] lat latitude of point (degrees). * @param[in] lon longitude of point (degrees). * @param[out] x easting of point (meters). * @param[out] y northing of point (meters). * @param[out] gamma meridian convergence at point (degrees). * @param[out] k scale of projection at point. * * \e lat should be in the range [−90°, 90°]. **********************************************************************/ static void Forward(double lat, double lon, [System::Runtime::InteropServices::Out] double% x, [System::Runtime::InteropServices::Out] double% y, [System::Runtime::InteropServices::Out] double% gamma, [System::Runtime::InteropServices::Out] double% k); /** * Reverse projection, from OSGB coordinates to geographic. * * @param[in] x easting of point (meters). * @param[in] y northing of point (meters). * @param[out] lat latitude of point (degrees). * @param[out] lon longitude of point (degrees). * @param[out] gamma meridian convergence at point (degrees). * @param[out] k scale of projection at point. * * The value of \e lon returned is in the range [−180°, * 180°). **********************************************************************/ static void Reverse(double x, double y, [System::Runtime::InteropServices::Out] double% lat, [System::Runtime::InteropServices::Out] double% lon, [System::Runtime::InteropServices::Out] double% gamma, [System::Runtime::InteropServices::Out] double% k); /** * OSGB::Forward without returning the convergence and scale. **********************************************************************/ static void Forward(double lat, double lon, [System::Runtime::InteropServices::Out] double% x, [System::Runtime::InteropServices::Out] double% y); /** * OSGB::Reverse without returning the convergence and scale. **********************************************************************/ static void Reverse(double x, double y, [System::Runtime::InteropServices::Out] double% lat, [System::Runtime::InteropServices::Out] double% lon); /** * Convert OSGB coordinates to a grid reference. * * @param[in] x easting of point (meters). * @param[in] y northing of point (meters). * @param[in] prec precision relative to 100 km. * @param[out] gridref National Grid reference. * @exception GeographicErr if \e prec, \e x, or \e y is outside its * allowed range. * @exception std::bad_alloc if the memory for \e gridref can't be * allocatied. * * \e prec specifies the precision of the grid reference string as follows: * - prec = 0 (min), 100km * - prec = 1, 10km * - prec = 2, 1km * - prec = 3, 100m * - prec = 4, 10m * - prec = 5, 1m * - prec = 6, 0.1m * - prec = 11 (max), 1μm * * The easting must be in the range [−1000 km, 1500 km) and the * northing must be in the range [−500 km, 2000 km). These bounds * are consistent with rules for the letter designations for the grid * system. * * If \e x or \e y is NaN, the returned grid reference is "INVALID". **********************************************************************/ static void GridReference(double x, double y, int prec, [System::Runtime::InteropServices::Out] System::String^% gridref); /** * Convert OSGB coordinates to a grid reference. * * @param[in] gridref National Grid reference. * @param[out] x easting of point (meters). * @param[out] y northing of point (meters). * @param[out] prec precision relative to 100 km. * @param[in] centerp if true (default), return center of the grid square, * else return SW (lower left) corner. * @exception GeographicErr if \e gridref is illegal. * * The grid reference must be of the form: two letters (not including I) * followed by an even number of digits (up to 22). * * If the first 2 characters of \e gridref are "IN", then \e x and \e y are * set to NaN and \e prec is set to −2. **********************************************************************/ static void GridReference(System::String^ gridref, [System::Runtime::InteropServices::Out] double% x, [System::Runtime::InteropServices::Out] double% y, [System::Runtime::InteropServices::Out] int% prec, bool centerp ); /** \name Inspector functions **********************************************************************/ ///@{ /** * @return \e a the equatorial radius of the Airy 1830 ellipsoid (meters). * * This is 20923713 ft converted to meters using the rule 1 ft = * 109.48401603−10 m. (The Airy 1830 value is returned * because the OSGB projection is based on this ellipsoid.) **********************************************************************/ static double EquatorialRadius(); /** * @return \e f the inverse flattening of the Airy 1830 ellipsoid. * * For the Airy 1830 ellipsoid, \e a = 20923713 ft and \e b = 20853810 ft; * thus the flattening = (20923713 − 20853810)/20923713 = * 7767/2324857 = 1/299.32496459... (The Airy 1830 value is returned * because the OSGB projection is based on this ellipsoid.) **********************************************************************/ static double Flattening(); /** * @return \e k0 central scale for the OSGB projection (0.9996012717). **********************************************************************/ static double CentralScale(); /** * @return latitude of the origin for the OSGB projection (49 degrees). **********************************************************************/ static double OriginLatitude(); /** * @return longitude of the origin for the OSGB projection (−2 * degrees). **********************************************************************/ static double OriginLongitude(); /** * @return false northing the OSGB projection (−100000 meters). **********************************************************************/ static double FalseNorthing(); /** * @return false easting the OSGB projection (400000 meters). **********************************************************************/ static double FalseEasting(); ///@} }; } //