/******************************************************************************
 * $Id: ogr_srs_panorama.cpp 17681 2009-09-25 08:41:18Z dron $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  OGRSpatialReference translation to/from "Panorama" GIS
 *           georeferencing information (also know as GIS "Integration").
 * Author:   Andrey Kiselev, dron@ak4719.spb.edu
 *
 ******************************************************************************
 * Copyright (c) 2005, Andrey Kiselev <dron@ak4719.spb.edu>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ****************************************************************************/

#include "ogr_spatialref.h"
#include "ogr_p.h"
#include "cpl_conv.h"
#include "cpl_csv.h"

CPL_CVSID("$Id: ogr_srs_panorama.cpp 17681 2009-09-25 08:41:18Z dron $");

#define TO_DEGREES 57.2957795130823208766
#define TO_RADIANS 0.017453292519943295769

// XXX: this macro computes zone number from the central meridian parameter.
// Note, that "Panorama" parameters are set in radians.
// In degrees it means formulae:
//
//              zone = (central_meridian + 3) / 6
//
#define TO_ZONE(x) (((x) + 0.05235987755982989) / 0.1047197551196597)

/************************************************************************/
/*  "Panorama" projection codes.                                        */
/************************************************************************/

#define PAN_PROJ_NONE   -1L
#define PAN_PROJ_TM     1L      // Gauss-Kruger (Transverse Mercator)
#define PAN_PROJ_LCC    2L      // Lambert Conformal Conic 2SP
#define PAN_PROJ_STEREO 5L      // Stereographic
#define PAN_PROJ_AE     6L      // Azimuthal Equidistant (Postel)
#define PAN_PROJ_MERCAT 8L      // Mercator
#define PAN_PROJ_POLYC  10L     // Polyconic
#define PAN_PROJ_PS     13L     // Polar Stereographic
#define PAN_PROJ_GNOMON 15L     // Gnomonic
#define PAN_PROJ_UTM    17L     // Universal Transverse Mercator (UTM)
#define PAN_PROJ_WAG1   18L     // Wagner I (Kavraisky VI)
#define PAN_PROJ_MOLL   19L     // Mollweide
#define PAN_PROJ_EC     20L     // Equidistant Conic
#define PAN_PROJ_LAEA   24L     // Lambert Azimuthal Equal Area
#define PAN_PROJ_EQC    27L     // Equirectangular
#define PAN_PROJ_CEA    28L     // Cylindrical Equal Area (Lambert)
#define PAN_PROJ_IMWP   29L     // International Map of the World Polyconic

/************************************************************************/
/*  "Panorama" datum codes.                                             */
/************************************************************************/

#define PAN_DATUM_NONE      -1L
#define PAN_DATUM_PULKOVO42 1L  // Pulkovo 1942
#define PAN_DATUM_WGS84     2L  // WGS84

/************************************************************************/
/*  "Panorama" ellipsod codes.                                          */
/************************************************************************/

#define PAN_ELLIPSOID_NONE          -1L
#define PAN_ELLIPSOID_KRASSOVSKY    1L  // Krassovsky, 1940
#define PAN_ELLIPSOID_WGS72         2L  // WGS, 1972
#define PAN_ELLIPSOID_INT1924       3L  // International, 1924 (Hayford, 1909)
#define PAN_ELLIPSOID_CLARCKE1880   4L  // Clarke, 1880
#define PAN_ELLIPSOID_CLARCKE1866   5L  // Clarke, 1866 (NAD1927)
#define PAN_ELLIPSOID_EVEREST1830   6L  // Everest, 1830
#define PAN_ELLIPSOID_BESSEL1841    7L  // Bessel, 1841
#define PAN_ELLIPSOID_AIRY1830      8L  // Airy, 1830
#define PAN_ELLIPSOID_WGS84         9L  // WGS, 1984 (GPS)

/************************************************************************/
/*  Correspondence between "Panorama" and EPSG datum codes.             */
/************************************************************************/

static const long aoDatums[] =
{
    0,
    4284,   // Pulkovo, 1942
    4326,   // WGS, 1984,
    4277,   // OSGB 1936 (British National Grid)
    0,
    0,
    0,
    0,
    0,
    4200    // Pulkovo, 1995
};

#define NUMBER_OF_DATUMS        (long)(sizeof(aoDatums)/sizeof(aoDatums[0]))

/************************************************************************/
/*  Correspondence between "Panorama" and EPSG ellipsoid codes.         */
/************************************************************************/

static const long aoEllips[] =
{
    0,
    7024,   // Krassovsky, 1940
    7043,   // WGS, 1972
    7022,   // International, 1924 (Hayford, 1909)
    7034,   // Clarke, 1880
    7008,   // Clarke, 1866 (NAD1927)
    7015,   // Everest, 1830
    7004,   // Bessel, 1841
    7001,   // Airy, 1830
    7030    // WGS, 1984 (GPS)
};

#define NUMBER_OF_ELLIPSOIDS    (sizeof(aoEllips)/sizeof(aoEllips[0]))

/************************************************************************/
/*                        OSRImportFromPanorama()                       */
/************************************************************************/

OGRErr OSRImportFromPanorama( OGRSpatialReferenceH hSRS,
                              long iProjSys, long iDatum, long iEllips,
                              double *padfPrjParams )

{
    return ((OGRSpatialReference *) hSRS)->importFromPanorama( iProjSys,
                                                               iDatum,iEllips,
                                                               padfPrjParams );
}

/************************************************************************/
/*                          importFromPanorama()                        */
/************************************************************************/

/**
 * Import coordinate system from "Panorama" GIS projection definition.
 *
 * This method will import projection definition in style, used by
 * "Panorama" GIS.
 *
 * This function is the equivalent of the C function OSRImportFromPanorama().
 *
 * @param iProjSys Input projection system code, used in GIS "Panorama".
 *
 *      <h4>Supported Projections</h4>
 * <pre>
 *      1:  Gauss-Kruger (Transverse Mercator)
 *      2:  Lambert Conformal Conic 2SP
 *      5:  Stereographic
 *      6:  Azimuthal Equidistant (Postel)
 *      8:  Mercator
 *      10: Polyconic
 *      13: Polar Stereographic
 *      15: Gnomonic
 *      17: Universal Transverse Mercator (UTM)
 *      18: Wagner I (Kavraisky VI)
 *      19: Mollweide
 *      20: Equidistant Conic
 *      24: Lambert Azimuthal Equal Area
 *      27: Equirectangular
 *      28: Cylindrical Equal Area (Lambert)
 *      29: International Map of the World Polyconic
 * </pre>
 *
 * @param iDatum Input coordinate system.
 *
 *      <h4>Supported Datums</h4>
 * <pre>
 *       1: Pulkovo, 1942
 *       2: WGS, 1984
 *       3: OSGB 1936 (British National Grid)
 *       9: Pulkovo, 1995
 * </pre>
 *
 * @param iEllips Input spheroid.
 * 
 *      <h4>Supported Spheroids</h4>
 * <pre>
 *       1: Krassovsky, 1940
 *       2: WGS, 1972
 *       3: International, 1924 (Hayford, 1909)
 *       4: Clarke, 1880
 *       5: Clarke, 1866 (NAD1927)
 *       6: Everest, 1830
 *       7: Bessel, 1841
 *       8: Airy, 1830
 *       9: WGS, 1984 (GPS)
 * </pre>
 *
 * @param padfPrjParams Array of 7 coordinate system parameters:
 *
 * <pre>
 *      [0]  Latitude of the first standard parallel (radians)
 *      [1]  Latitude of the second standard parallel (radians)
 *      [2]  Latitude of center of projection (radians)
 *      [3]  Longitude of center of projection (radians)
 *      [4]  Scaling factor
 *      [5]  False Easting
 *      [6]  False Northing
 * </pre>
 *
 * Particular projection uses different parameters, unused ones may be set to
 * zero. If NULL supplied instead of array pointer default values will be used
 * (i.e., zeroes).
 *
 * @return OGRERR_NONE on success or an error code in case of failure. 
 */

OGRErr OGRSpatialReference::importFromPanorama( long iProjSys, long iDatum,
                                                long iEllips,
                                                double *padfPrjParams )

{
    Clear();

/* -------------------------------------------------------------------- */
/*      Use safe defaults if projection parameters are not supplied.    */
/* -------------------------------------------------------------------- */
    int     bProjAllocated = FALSE;

    if( padfPrjParams == NULL )
    {
        int     i;

        padfPrjParams = (double *)CPLMalloc( 7 * sizeof(double) );
        if ( !padfPrjParams )
            return OGRERR_NOT_ENOUGH_MEMORY;
        for ( i = 0; i < 7; i++ )
            padfPrjParams[i] = 0.0;
        bProjAllocated = TRUE;
    }

/* -------------------------------------------------------------------- */
/*      Operate on the basis of the projection code.                    */
/* -------------------------------------------------------------------- */
    switch ( iProjSys )
    {
        case PAN_PROJ_NONE:
            break;

        case PAN_PROJ_UTM:
            {
                long nZone = (long)TO_ZONE(padfPrjParams[3]);

                // XXX: no way to determine south hemisphere. Always assume
                // nothern hemisphere.
                SetUTM( nZone, TRUE );
            }
            break;

        case PAN_PROJ_WAG1:
            SetWagner( 1, 0.0,
                       padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_MERCAT:
            SetMercator( TO_DEGREES * padfPrjParams[0],
                         TO_DEGREES * padfPrjParams[3],
                         padfPrjParams[4],
                         padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_PS:
            SetPS( TO_DEGREES * padfPrjParams[2],
                   TO_DEGREES * padfPrjParams[3],
                   padfPrjParams[4],
                   padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_POLYC:
            SetPolyconic( TO_DEGREES * padfPrjParams[2],
                          TO_DEGREES * padfPrjParams[3],
                          padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_EC:
            SetEC( TO_DEGREES * padfPrjParams[0],
                   TO_DEGREES * padfPrjParams[1],
                   TO_DEGREES * padfPrjParams[2],
                   TO_DEGREES * padfPrjParams[3],
                   padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_LCC:
            SetLCC( TO_DEGREES * padfPrjParams[0],
                    TO_DEGREES * padfPrjParams[1],
                    TO_DEGREES * padfPrjParams[2],
                    TO_DEGREES * padfPrjParams[3],
                    padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_TM:
            {
                // XXX: we need zone number to compute false easting
                // parameter, because usually it is not contained in the
                // "Panorama" projection definition.
                // FIXME: what to do with negative values?
                long nZone = (long)TO_ZONE(padfPrjParams[3]);

                padfPrjParams[5] = nZone * 1000000.0 + 500000.0;
                padfPrjParams[4] = 1.0;
                SetTM( TO_DEGREES * padfPrjParams[2],
                       TO_DEGREES * padfPrjParams[3],
                       padfPrjParams[4],
                       padfPrjParams[5], padfPrjParams[6] );
            }
            break;

        case PAN_PROJ_STEREO:
            SetStereographic( TO_DEGREES * padfPrjParams[2],
                              TO_DEGREES * padfPrjParams[3],
                              padfPrjParams[4],
                              padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_AE:
            SetAE( TO_DEGREES * padfPrjParams[0],
                   TO_DEGREES * padfPrjParams[3],
                   padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_GNOMON:
            SetGnomonic( TO_DEGREES * padfPrjParams[2],
                         TO_DEGREES * padfPrjParams[3],
                         padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_MOLL:
            SetMollweide( TO_DEGREES * padfPrjParams[3],
                          padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_LAEA:
            SetLAEA( TO_DEGREES * padfPrjParams[0],
                     TO_DEGREES * padfPrjParams[3],
                     padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_EQC:
            SetEquirectangular( TO_DEGREES * padfPrjParams[0],
                                TO_DEGREES * padfPrjParams[3],
                                padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_CEA:
            SetCEA( TO_DEGREES * padfPrjParams[0],
                    TO_DEGREES * padfPrjParams[3],
                    padfPrjParams[5], padfPrjParams[6] );
            break;

        case PAN_PROJ_IMWP:
            SetIWMPolyconic( TO_DEGREES * padfPrjParams[0],
                             TO_DEGREES * padfPrjParams[1],
                             TO_DEGREES * padfPrjParams[3],
                             padfPrjParams[5], padfPrjParams[6] );
            break;

        default:
            CPLDebug( "OSR_Panorama", "Unsupported projection: %ld", iProjSys );
            SetLocalCS( CPLString().Printf("\"Panorama\" projection number %ld",
                                   iProjSys) );
            break;
            
    }

/* -------------------------------------------------------------------- */
/*      Try to translate the datum/spheroid.                            */
/* -------------------------------------------------------------------- */

    if ( !IsLocal() )
    {
        if ( iDatum > 0 && iDatum < NUMBER_OF_DATUMS && aoDatums[iDatum] )
        {
            OGRSpatialReference oGCS;
            oGCS.importFromEPSG( aoDatums[iDatum] );
            CopyGeogCSFrom( &oGCS );
        }

        else if ( iEllips > 0
                  && iEllips < (long)NUMBER_OF_ELLIPSOIDS
                  && aoEllips[iEllips] )
        {
            char    *pszName = NULL;
            double  dfSemiMajor, dfInvFlattening;

            if ( OSRGetEllipsoidInfo( aoEllips[iEllips], &pszName,
                            &dfSemiMajor, &dfInvFlattening ) == OGRERR_NONE )
            {
                SetGeogCS( CPLString().Printf(
                            "Unknown datum based upon the %s ellipsoid",
                            pszName ),
                           CPLString().Printf(
                            "Not specified (based on %s spheroid)", pszName ),
                           pszName, dfSemiMajor, dfInvFlattening,
                           NULL, 0.0, NULL, 0.0 );
                SetAuthority( "SPHEROID", "EPSG", aoEllips[iEllips] );
            }
            else
            {
                CPLError( CE_Warning, CPLE_AppDefined,
                          "Failed to lookup ellipsoid code %d, likely due to"
                          " missing GDAL gcs.csv\n"
                          " file.  Falling back to use WGS84.", (int) iEllips );
                SetWellKnownGeogCS( "WGS84" );
            }

            if ( pszName )
                CPLFree( pszName );
        }
        
        else
        {
            CPLError( CE_Warning, CPLE_AppDefined,
                      "Wrong datum code %d. Supported datums are 1--%ld only.\n"
                      "Setting WGS84 as a fallback.",
                      (int) iDatum, NUMBER_OF_DATUMS - 1 );
            SetWellKnownGeogCS( "WGS84" );
        }
    }

/* -------------------------------------------------------------------- */
/*      Grid units translation                                          */
/* -------------------------------------------------------------------- */
    if( IsLocal() || IsProjected() )
        SetLinearUnits( SRS_UL_METER, 1.0 );

    FixupOrdering();

    if ( bProjAllocated && padfPrjParams )
        CPLFree( padfPrjParams );

    return OGRERR_NONE;
}

/************************************************************************/
/*                      OSRExportToPanorama()                           */
/************************************************************************/

OGRErr OSRExportToPanorama( OGRSpatialReferenceH hSRS,
                            long *piProjSys, long *piDatum, long *piEllips,
                            long *piZone, double *padfPrjParams )

{
    return ((OGRSpatialReference *) hSRS)->exportToPanorama( piProjSys,
                                                             piDatum, piEllips,
                                                             piZone,
                                                             padfPrjParams );
}

/************************************************************************/
/*                           exportToPanorama()                         */
/************************************************************************/

/**
 * Export coordinate system in "Panorama" GIS projection definition.
 *
 * This method is the equivalent of the C function OSRExportToPanorama().
 *
 * @param piProjSys Pointer to variable, where the projection system code will
 * be returned.
 *
 * @param piDatum Pointer to variable, where the coordinate system code will
 * be returned.
 *
 * @param piEllips Pointer to variable, where the spheroid code will be
 * returned.
 * 
 * @param piZone Pointer to variable, where the zone for UTM projection
 * system will be returned.
 *
 * @param padfPrjParams an existing 7 double buffer into which the
 * projection parameters will be placed. See importFromPanorama()
 * for the list of parameters.
 * 
 * @return OGRERR_NONE on success or an error code on failure. 
 */

OGRErr OGRSpatialReference::exportToPanorama( long *piProjSys, long *piDatum,
                                              long *piEllips, long *piZone,
                                              double *padfPrjParams ) const

{
    CPLAssert( padfPrjParams );

    const char  *pszProjection = GetAttrValue("PROJECTION");

/* -------------------------------------------------------------------- */
/*      Fill all projection parameters with zero.                       */
/* -------------------------------------------------------------------- */
    int     i;

    *piDatum = 0L;
    *piEllips = 0L;
    *piZone = 0L;
    for ( i = 0; i < 7; i++ )
        padfPrjParams[i] = 0.0;

/* ==================================================================== */
/*      Handle the projection definition.                               */
/* ==================================================================== */
    if( IsLocal() )
        *piProjSys = PAN_PROJ_NONE;

    else if( pszProjection == NULL )
    {
#ifdef DEBUG
        CPLDebug( "OSR_Panorama",
                  "Empty projection definition, considered as Geographic" );
#endif
        *piProjSys = PAN_PROJ_NONE;
    }

    else if( EQUAL(pszProjection, SRS_PT_MERCATOR_1SP) )
    {
        *piProjSys = PAN_PROJ_MERCAT;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[0] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[4] = GetNormProjParm( SRS_PP_SCALE_FACTOR, 1.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_POLAR_STEREOGRAPHIC) )
    {
        *piProjSys = PAN_PROJ_PS;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[4] = GetNormProjParm( SRS_PP_SCALE_FACTOR, 1.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_POLYCONIC) )
    {
        *piProjSys = PAN_PROJ_POLYC;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_EQUIDISTANT_CONIC) )
    {
        *piProjSys = PAN_PROJ_EC;
        padfPrjParams[0] =
            TO_RADIANS * GetNormProjParm( SRS_PP_STANDARD_PARALLEL_1, 0.0 );
        padfPrjParams[1] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_STANDARD_PARALLEL_2, 0.0 );
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_LAMBERT_CONFORMAL_CONIC_2SP) )
    {
        *piProjSys = PAN_PROJ_LCC;
        padfPrjParams[0] =
            TO_RADIANS * GetNormProjParm( SRS_PP_STANDARD_PARALLEL_1, 0.0 );
        padfPrjParams[1] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_STANDARD_PARALLEL_2, 0.0 );
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_TRANSVERSE_MERCATOR) )
    {
        int bNorth;

        *piZone = GetUTMZone( &bNorth );

        if( *piZone != 0 )
        {
            *piProjSys = PAN_PROJ_UTM;
            if( !bNorth )
                *piZone = - *piZone;
        }            
        else
        {
            *piProjSys = PAN_PROJ_TM;
            padfPrjParams[3] =
                TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
            padfPrjParams[2] = 
                TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
            padfPrjParams[4] =
                GetNormProjParm( SRS_PP_SCALE_FACTOR, 1.0 );
            padfPrjParams[5] =
                GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
            padfPrjParams[6] =
                GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
        }
    }

    else if( EQUAL(pszProjection, SRS_PT_WAGNER_I) )
    {
        *piProjSys = PAN_PROJ_WAG1;
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_STEREOGRAPHIC) )
    {
        *piProjSys = PAN_PROJ_STEREO;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[4] = GetNormProjParm( SRS_PP_SCALE_FACTOR, 1.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_AZIMUTHAL_EQUIDISTANT) )
    {
        *piProjSys = PAN_PROJ_AE;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_LONGITUDE_OF_CENTER, 0.0 );
        padfPrjParams[0] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_CENTER, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_GNOMONIC) )
    {
        *piProjSys = PAN_PROJ_GNOMON;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_MOLLWEIDE) )
    {
        *piProjSys = PAN_PROJ_MOLL;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_LAMBERT_AZIMUTHAL_EQUAL_AREA) )
    {
        *piProjSys = PAN_PROJ_LAEA;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[0] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_EQUIRECTANGULAR) )
    {
        *piProjSys = PAN_PROJ_EQC;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[0] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_ORIGIN, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_CYLINDRICAL_EQUAL_AREA) )
    {
        *piProjSys = PAN_PROJ_CEA;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[2] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_STANDARD_PARALLEL_1, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    else if( EQUAL(pszProjection, SRS_PT_IMW_POLYCONIC) )
    {
        *piProjSys = PAN_PROJ_IMWP;
        padfPrjParams[3] =
            TO_RADIANS * GetNormProjParm( SRS_PP_CENTRAL_MERIDIAN, 0.0 );
        padfPrjParams[0] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_1ST_POINT, 0.0 );
        padfPrjParams[1] = 
            TO_RADIANS * GetNormProjParm( SRS_PP_LATITUDE_OF_2ND_POINT, 0.0 );
        padfPrjParams[5] = GetNormProjParm( SRS_PP_FALSE_EASTING, 0.0 );
        padfPrjParams[6] = GetNormProjParm( SRS_PP_FALSE_NORTHING, 0.0 );
    }

    // Projection unsupported by "Panorama" GIS
    else
    {
        CPLDebug( "OSR_Panorama",
                  "Projection \"%s\" unsupported by \"Panorama\" GIS. "
                  "Geographic system will be used.", pszProjection );
        *piProjSys = PAN_PROJ_NONE;
    }
 
/* -------------------------------------------------------------------- */
/*      Translate the datum.                                            */
/* -------------------------------------------------------------------- */
    const char  *pszDatum = GetAttrValue( "DATUM" );

    if ( pszDatum == NULL )
    {
        *piDatum = PAN_DATUM_NONE;
        *piEllips = PAN_ELLIPSOID_NONE;
    }
    else if ( EQUAL( pszDatum, "Pulkovo_1942" ) )
    {
        *piDatum = PAN_DATUM_PULKOVO42;
        *piEllips = PAN_ELLIPSOID_KRASSOVSKY;
    }
    else if( EQUAL( pszDatum, SRS_DN_WGS84 ) )
    {
        *piDatum = PAN_DATUM_WGS84;
        *piEllips = PAN_ELLIPSOID_WGS84;
    }

    // If not found well known datum, translate ellipsoid
    else
    {
        double      dfSemiMajor = GetSemiMajor();
        double      dfInvFlattening = GetInvFlattening();
        size_t      i;

#ifdef DEBUG
        CPLDebug( "OSR_Panorama",
                  "Datum \"%s\" unsupported by \"Panorama\" GIS. "
                  "Try to translate ellipsoid definition.", pszDatum );
#endif
       
        for ( i = 0; i < NUMBER_OF_ELLIPSOIDS; i++ )
        {
            if ( aoEllips[i] )
            {
                double  dfSM = 0.0;
                double  dfIF = 1.0;

                if ( OSRGetEllipsoidInfo( aoEllips[i], NULL,
                                          &dfSM, &dfIF ) == OGRERR_NONE
                     && CPLIsEqual(dfSemiMajor, dfSM)
                     && CPLIsEqual(dfInvFlattening, dfIF) )
                {
                    *piEllips = i;
                    break;
                }
            }
        }

        if ( i == NUMBER_OF_ELLIPSOIDS )    // Didn't found matches.
        {
#ifdef DEBUG
            CPLDebug( "OSR_Panorama",
                      "Ellipsoid \"%s\" unsupported by \"Panorama\" GIS.",
                      pszDatum );
#endif
            *piDatum = PAN_DATUM_NONE;
            *piEllips = PAN_ELLIPSOID_NONE;
        }
    }

    return OGRERR_NONE;
}

