// fg_geodesy.hxx -- routines to convert between geodetic and geocentric // coordinate systems. // // Copied and adapted directly from LaRCsim/ls_geodesy.c // // See below for the complete original LaRCsim comments. // // $Id$ // (Log is kept at end of this file) #ifndef _FG_GEODESY_HXX #define _FG_GEODESY_HXX #ifndef __cplusplus # error This library requires C++ #endif #include #include // fgGeocToGeod(lat_geoc, radius, *lat_geod, *alt, *sea_level_r) // INPUTS: // lat_geoc Geocentric latitude, radians, + = North // radius C.G. radius to earth center (meters) // // OUTPUTS: // lat_geod Geodetic latitude, radians, + = North // alt C.G. altitude above mean sea level (meters) // sea_level_r radius from earth center to sea level at // local vertical (surface normal) of C.G. (meters) void fgGeocToGeod( double lat_geoc, double radius, double *lat_geod, double *alt, double *sea_level_r ); // fgGeodToGeoc( lat_geod, alt, *sl_radius, *lat_geoc ) // INPUTS: // lat_geod Geodetic latitude, radians, + = North // alt C.G. altitude above mean sea level (meters) // // OUTPUTS: // sl_radius SEA LEVEL radius to earth center (meters) // (add Altitude to get true distance from earth center. // lat_geoc Geocentric latitude, radians, + = North // void fgGeodToGeoc( double lat_geod, double alt, double *sl_radius, double *lat_geoc ); // convert a geodetic point lon(radians), lat(radians), elev(meter) to // a cartesian point inline Point3D fgGeodToCart(const Point3D& geod) { double gc_lon, gc_lat, sl_radius; // printf("A geodetic point is (%.2f, %.2f, %.2f)\n", // geod[0], geod[1], geod[2]); gc_lon = geod.lon(); fgGeodToGeoc(geod.lat(), geod.radius(), &sl_radius, &gc_lat); // printf("A geocentric point is (%.2f, %.2f, %.2f)\n", gc_lon, // gc_lat, sl_radius+geod[2]); Point3D pp = Point3D( gc_lon, gc_lat, sl_radius + geod.radius()); return fgPolarToCart3d(pp); } /*************************************************************************** TITLE: ls_geodesy ---------------------------------------------------------------------------- FUNCTION: Converts geocentric coordinates to geodetic positions ---------------------------------------------------------------------------- MODULE STATUS: developmental ---------------------------------------------------------------------------- GENEALOGY: Written as part of LaRCSim project by E. B. Jackson ---------------------------------------------------------------------------- DESIGNED BY: E. B. Jackson CODED BY: E. B. Jackson MAINTAINED BY: E. B. Jackson ---------------------------------------------------------------------------- MODIFICATION HISTORY: DATE PURPOSE BY 930208 Modified to avoid singularity near polar region. EBJ 930602 Moved backwards calcs here from ls_step. EBJ 931214 Changed erroneous Latitude and Altitude variables to *lat_geod and *alt in routine ls_geoc_to_geod. EBJ 940111 Changed header files from old ls_eom.h style to ls_types, and ls_constants. Also replaced old DATA type with new SCALAR type. EBJ CURRENT RCS HEADER: $Header$ $Log$ Revision 1.4 1999/01/27 04:46:15 curt Portability tweaks by Bernie Bright. Revision 1.3 1998/10/18 01:17:11 curt Point3D tweaks. Revision 1.2 1998/10/16 23:36:37 curt c++-ifying. Revision 1.1 1998/10/16 19:30:42 curt Renamed .c -> .h so we can start adding c++ supporting routines. Revision 1.4 1998/07/08 14:40:08 curt polar3d.[ch] renamed to polar3d.[ch]xx, vector.[ch] renamed to vector.[ch]xx Updated fg_geodesy comments to reflect that routines expect and produce meters. Revision 1.3 1998/04/21 17:03:48 curt Prepairing for C++ integration. Revision 1.2 1998/01/22 02:59:38 curt Changed #ifdef FILE_H to #ifdef _FILE_H Revision 1.1 1997/07/31 23:13:14 curt Initial revision. Revision 1.1 1997/05/29 00:09:56 curt Initial Flight Gear revision. * Revision 1.5 1994/01/11 18:47:05 bjax * Changed include files to use types and constants, not ls_eom.h * Also changed DATA type to SCALAR type. * * Revision 1.4 1993/12/14 21:06:47 bjax * Removed global variable references Altitude and Latitude. EBJ * * Revision 1.3 1993/06/02 15:03:40 bjax * Made new subroutine for calculating geodetic to geocentric; changed name * of forward conversion routine from ls_geodesy to ls_geoc_to_geod. * ---------------------------------------------------------------------------- REFERENCES: [ 1] Stevens, Brian L.; and Lewis, Frank L.: "Aircraft Control and Simulation", Wiley and Sons, 1992. ISBN 0-471-61397-5 ---------------------------------------------------------------------------- CALLED BY: ls_aux ---------------------------------------------------------------------------- CALLS TO: ---------------------------------------------------------------------------- INPUTS: lat_geoc Geocentric latitude, radians, + = North radius C.G. radius to earth center, ft ---------------------------------------------------------------------------- OUTPUTS: lat_geod Geodetic latitude, radians, + = North alt C.G. altitude above mean sea level, ft sea_level_r radius from earth center to sea level at local vertical (surface normal) of C.G. --------------------------------------------------------------------------*/ #endif // _FG_GEODESY_HXX // $Log$ // Revision 1.4 1999/01/27 04:46:15 curt // Portability tweaks by Bernie Bright. // // Revision 1.3 1998/10/18 01:17:11 curt // Point3D tweaks. // // Revision 1.2 1998/10/16 23:36:37 curt // c++-ifying. // // Revision 1.1 1998/10/16 19:30:42 curt // Renamed .c -> .h so we can start adding c++ supporting routines. // // Revision 1.4 1998/07/08 14:40:08 curt // polar3d.[ch] renamed to polar3d.[ch]xx, vector.[ch] renamed to vector.[ch]xx // Updated fg_geodesy comments to reflect that routines expect and produce // meters. // // Revision 1.3 1998/04/21 17:03:48 curt // Prepairing for C++ integration. // // Revision 1.2 1998/01/22 02:59:38 curt // Changed #ifdef FILE_H to #ifdef _FILE_H // // Revision 1.1 1997/07/31 23:13:14 curt // Initial revision. //