Application: gvSIG desktop

#ifndef GEOCENT_H

#define GEOCENT_H

/***************************************************************************/

/* RSC IDENTIFIER:  GEOCENTRIC

 *

 * ABSTRACT

 *

 *    This component provides conversions between Geodetic coordinates (latitude,

 *    longitude in radians and height in meters) and Geocentric coordinates

 *    (X, Y, Z) in meters.

 *

 * ERROR HANDLING

 *

 *    This component checks parameters for valid values.  If an invalid value

 *    is found, the error code is combined with the current error code using 

 *    the bitwise or.  This combining allows multiple error codes to be

 *    returned. The possible error codes are:

 *

 *      GEOCENT_NO_ERROR        : No errors occurred in function

 *      GEOCENT_LAT_ERROR       : Latitude out of valid range

 *                                 (-90 to 90 degrees)

 *      GEOCENT_LON_ERROR       : Longitude out of valid range

 *                                 (-180 to 360 degrees)

 *      GEOCENT_A_ERROR         : Semi-major axis less than or equal to zero

 *      GEOCENT_B_ERROR         : Semi-minor axis less than or equal to zero

 *      GEOCENT_A_LESS_B_ERROR  : Semi-major axis less than semi-minor axis

 *

 *

 * REUSE NOTES

 *

 *    GEOCENTRIC is intended for reuse by any application that performs

 *    coordinate conversions between geodetic coordinates and geocentric

 *    coordinates.

 *    

 *

 * REFERENCES

 *    

 *    An Improved Algorithm for Geocentric to Geodetic Coordinate Conversion,

 *    Ralph Toms, February 1996  UCRL-JC-123138.

 *    

 *    Further information on GEOCENTRIC can be found in the Reuse Manual.

 *

 *    GEOCENTRIC originated from : U.S. Army Topographic Engineering Center

 *                                 Geospatial Information Division

 *                                 7701 Telegraph Road

 *                                 Alexandria, VA  22310-3864

 *

 * LICENSES

 *

 *    None apply to this component.

 *

 * RESTRICTIONS

 *

 *    GEOCENTRIC has no restrictions.

 *

 * ENVIRONMENT

 *

 *    GEOCENTRIC was tested and certified in the following environments:

 *

 *    1. Solaris 2.5 with GCC version 2.8.1

 *    2. Windows 95 with MS Visual C++ version 6

 *

 * MODIFICATIONS

 *

 *    Date              Description

 *    ----              -----------

 *

 *

 */

/***************************************************************************/

/*

 *                              DEFINES

 */

#define GEOCENT_NO_ERROR        0x0000

#define GEOCENT_LAT_ERROR       0x0001

#define GEOCENT_LON_ERROR       0x0002

#define GEOCENT_A_ERROR         0x0004

#define GEOCENT_B_ERROR         0x0008

#define GEOCENT_A_LESS_B_ERROR  0x0010

/***************************************************************************/

/*

 *                              FUNCTION PROTOTYPES

 */

/* ensure proper linkage to c++ programs */

#ifdef __cplusplus

extern "C" {

#endif

  long pj_Set_Geocentric_Parameters (double a, 

                                  double b);

/*

 * The function Set_Geocentric_Parameters receives the ellipsoid parameters

 * as inputs and sets the corresponding state variables.

 *

 *    a  : Semi-major axis, in meters.          (input)

 *    b  : Semi-minor axis, in meters.          (input)

 */

  void pj_Get_Geocentric_Parameters (double *a, 

                                  double *b);

/*

 * The function Get_Geocentric_Parameters returns the ellipsoid parameters

 * to be used in geocentric coordinate conversions.

 *

 *    a  : Semi-major axis, in meters.          (output)

 *    b  : Semi-minor axis, in meters.          (output)

 */

  long pj_Convert_Geodetic_To_Geocentric (double Latitude,

                                       double Longitude,

                                       double Height,

                                       double *X,

                                       double *Y,

                                       double *Z);

/*

 * The function Convert_Geodetic_To_Geocentric converts geodetic coordinates

 * (latitude, longitude, and height) to geocentric coordinates (X, Y, Z),

 * according to the current ellipsoid parameters.

 *

 *    Latitude  : Geodetic latitude in radians                     (input)

 *    Longitude : Geodetic longitude in radians                    (input)

 *    Height    : Geodetic height, in meters                       (input)

 *    X         : Calculated Geocentric X coordinate, in meters.   (output)

 *    Y         : Calculated Geocentric Y coordinate, in meters.   (output)

 *    Z         : Calculated Geocentric Z coordinate, in meters.   (output)

 *

 */

  void pj_Convert_Geocentric_To_Geodetic (double X,

                                       double Y, 

                                       double Z,

                                       double *Latitude,

                                       double *Longitude,

                                       double *Height);

/*

 * The function Convert_Geocentric_To_Geodetic converts geocentric

 * coordinates (X, Y, Z) to geodetic coordinates (latitude, longitude, 

 * and height), according to the current ellipsoid parameters.

 *

 *    X         : Geocentric X coordinate, in meters.         (input)

 *    Y         : Geocentric Y coordinate, in meters.         (input)

 *    Z         : Geocentric Z coordinate, in meters.         (input)

 *    Latitude  : Calculated latitude value in radians.       (output)

 *    Longitude : Calculated longitude value in radians.      (output)

 *    Height    : Calculated height value, in meters.         (output)

 */

#ifdef __cplusplus

}

#endif

#endif /* GEOCENT_H */