/**********************************************************************
 * $Id: mitab_spatialref.cpp,v 1.6 2000/01/26 21:58:13 warmerda Exp $
 *
 * Name:     mitab_spatialref.cpp
 * Project:  MapInfo TAB Read/Write library
 * Language: C++
 * Purpose:  Implementation of the SpatialRef stuff in the TABFile class.
 * Author:   Frank Warmerdam, warmerda@home.com
 *
 **********************************************************************
 * Copyright (c) 1999, 2000, Frank Warmerdam
 *
 * 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.
 **********************************************************************
 *
 * $Log: mitab_spatialref.cpp,v $
 * Revision 1.6  2000/01/26 21:58:13  warmerda
 * reimport
 *
 * Revision 1.17  2000/01/15 22:30:45  daniel
 * Switch to MIT/X-Consortium OpenSource license
 *
 * Revision 1.16  1999/12/21 20:01:47  warmerda
 * added support for DATUM 0
 *
 * Revision 1.15  1999/11/11 02:56:17  warmerda
 * fixed problems with stereographic
 *
 * Revision 1.14  1999/11/10 20:13:12  warmerda
 * implement spheroid table
 *
 * Revision 1.13  1999/11/09 22:31:38  warmerda
 * initial implementation of MIF CoordSys support
 *
 * Revision 1.12  1999/10/19 16:31:32  warmerda
 * Improved mile support.
 *
 * Revision 1.11  1999/10/19 16:27:50  warmerda
 * Added support for Mile (units=0).  Also added support for nonearth
 * projections.
 *
 * Revision 1.10  1999/10/05 18:56:08  warmerda
 * fixed lots of bugs with projection parameters
 *
 * Revision 1.9  1999/10/04 21:17:47  warmerda
 * Make sure that asDatumInfoList comparisons include the ellipsoid code.
 * Don't include OGC name for local NAD27 values.  Put NAD83 ahead of GRS80
 * so it will be used in preference even though they are identical parms.
 *
 * Revision 1.8  1999/10/04 19:46:42  warmerda
 * assorted changes, including rework of units
 *
 * Revision 1.7  1999/09/28 04:52:17  daniel
 * Added missing param in sprintf() format for szDatumName[]
 *
 * Revision 1.6  1999/09/28 02:51:46  warmerda
 * Added ellipsoid codes, and bulk of write implementation.
 *
 * Revision 1.5  1999/09/27 21:23:41  warmerda
 * added more projections
 *
 * Revision 1.4  1999/09/24 04:01:28  warmerda
 * remember nMIDatumId changes
 *
 * Revision 1.3  1999/09/23 19:51:38  warmerda
 * added datum mapping table support
 *
 * Revision 1.2  1999/09/22 23:04:59  daniel
 * Handle reference count on OGRSpatialReference properly
 *
 * Revision 1.1  1999/09/21 19:39:22  daniel
 * Moved Get/SetSpatialRef() to a separate file
 *
 **********************************************************************/

#include "mitab.h"

/* -------------------------------------------------------------------- */
/*      This table was automatically generated by doing translations    */
/*      between mif and tab for each datum, and extracting the          */
/*      parameters from the tab file.  The OGC names were added         */
/*      afterwards and may be incomplete or inaccurate.                 */
/* -------------------------------------------------------------------- */
MapInfoDatumInfo asDatumInfoList[] =
{
{104, "WGS_1984", 28, 0, 0, 0, 0, 0, 0, 0, 0},
{74, "North_American_Datum_1983", 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, "", 29, 0, 0, 0, 0, 0, 0, 0, 0},
{1, "Adindan", 6, -162, -12, 206, 0, 0, 0, 0, 0},
{2, "Afgooye", 3, -43, -163, 45, 0, 0, 0, 0, 0},
{3, "Ain_el_Abd_1970", 4, -150, -251, -2, 0, 0, 0, 0, 0},
{4, "", 2, -491, -22, 435, 0, 0, 0, 0, 0},
{5, "Arc_1950", 15, -143, -90, -294, 0, 0, 0, 0, 0},
{6, "Arc_1960", 6, -160, -8, -300, 0, 0, 0, 0, 0},
{7, "", 4, -207, 107, 52, 0, 0, 0, 0, 0},
{8, "", 4, 145, 75, -272, 0, 0, 0, 0, 0},
{9, "", 4, 114, -116, -333, 0, 0, 0, 0, 0},
{10, "", 4, -320, 550, -494, 0, 0, 0, 0, 0},
{11, "", 4, 124, -234, -25, 0, 0, 0, 0, 0},
{12, "", 2, -133, -48, 148, 0, 0, 0, 0, 0},
{13, "", 2, -134, -48, 149, 0, 0, 0, 0, 0},
{14, "", 4, -127, -769, 472, 0, 0, 0, 0, 0},
{15, "Bermuda_1957", 7, -73, 213, 296, 0, 0, 0, 0, 0},
{16, "Bogota", 4, 307, 304, -318, 0, 0, 0, 0, 0},
{17, "Campo_Inchanspe", 4, -148, 136, 90, 0, 0, 0, 0, 0},
{18, "", 4, 298, -304, -375, 0, 0, 0, 0, 0},
{19, "Cape", 6, -136, -108, -292, 0, 0, 0, 0, 0},
{20, "", 7, -2, 150, 181, 0, 0, 0, 0, 0},
{21, "Carthage", 6, -263, 6, 431, 0, 0, 0, 0, 0},
{22, "", 4, 175, -38, 113, 0, 0, 0, 0, 0},
{23, "Chua", 4, -134, 229, -29, 0, 0, 0, 0, 0},
{24, "Corrego_Alegre", 4, -206, 172, -6, 0, 0, 0, 0, 0},
{25, "Batavia", 10, -377, 681, -50, 0, 0, 0, 0, 0},
{26, "", 4, 230, -199, -752, 0, 0, 0, 0, 0},
{27, "", 4, 211, 147, 111, 0, 0, 0, 0, 0},
{28, "European_Datum_1950", 4, -87, -98, -121, 0, 0, 0, 0, 0},
{29, "", 4, -86, -98, -119, 0, 0, 0, 0, 0},
{30, "Gandajika_1970", 4, -133, -321, 50, 0, 0, 0, 0, 0},
{31, "", 4, 84, -22, 209, 0, 0, 0, 0, 0},
{32, "", 21, 0, 0, 0, 0, 0, 0, 0, 0},
{33, "", 0, 0, 0, 0, 0, 0, 0, 0, 0},
{34, "", 7, -100, -248, 259, 0, 0, 0, 0, 0},
{35, "", 4, 252, -209, -751, 0, 0, 0, 0, 0},
{36, "Hito_XVIII_1963", 4, 16, 196, 93, 0, 0, 0, 0, 0},
{37, "", 4, -73, 46, -86, 0, 0, 0, 0, 0},
{38, "", 4, -156, -271, -189, 0, 0, 0, 0, 0},
{39, "Hu_Tzu_Shan", 4, -634, -549, -201, 0, 0, 0, 0, 0},
{40, "", 11, 214, 836, 303, 0, 0, 0, 0, 0},
{41, "", 11, 289, 734, 257, 0, 0, 0, 0, 0},
{42, "", 13, 506, -122, 611, 0, 0, 0, 0, 0},
{43, "", 4, 208, -435, -229, 0, 0, 0, 0, 0},
{44, "", 4, 191, -77, -204, 0, 0, 0, 0, 0},
{45, "Kandawala", 11, -97, 787, 86, 0, 0, 0, 0, 0},
{46, "", 4, 145, -187, 103, 0, 0, 0, 0, 0},
{47, "Kertau", 17, -11, 851, 5, 0, 0, 0, 0, 0},
{48, "", 7, 42, 124, 147, 0, 0, 0, 0, 0},
{49, "Liberia_1964", 6, -90, 40, 88, 0, 0, 0, 0, 0},
{50, "", 7, -133, -77, -51, 0, 0, 0, 0, 0},
{51, "", 7, -133, -79, -72, 0, 0, 0, 0, 0},
{52, "Mahe_1971", 6, 41, -220, -134, 0, 0, 0, 0, 0},
{53, "", 4, -289, -124, 60, 0, 0, 0, 0, 0},
{54, "Massawa", 10, 639, 405, 60, 0, 0, 0, 0, 0},
{55, "", 16, 31, 146, 47, 0, 0, 0, 0, 0},
{56, "", 4, 912, -58, 1227, 0, 0, 0, 0, 0},
{57, "Minna", 6, -92, -93, 122, 0, 0, 0, 0, 0},
{58, "", 6, -247, -148, 369, 0, 0, 0, 0, 0},
{59, "", 6, -249, -156, 381, 0, 0, 0, 0, 0},
{60, "", 6, -231, -196, 482, 0, 0, 0, 0, 0},
{61, "Naparima_1972", 4, -2, 374, 172, 0, 0, 0, 0, 0},
{62, "North_American_Datum_1927", 7, -8, 160, 176, 0, 0, 0, 0, 0},
{63, "", 7, -5, 135, 172, 0, 0, 0, 0, 0},
{64, "", 7, -4, 154, 178, 0, 0, 0, 0, 0},
{65, "", 7, 1, 140, 165, 0, 0, 0, 0, 0},
{66, "", 7, -10, 158, 187, 0, 0, 0, 0, 0},
{67, "", 7, 0, 125, 201, 0, 0, 0, 0, 0},
{68, "", 7, -7, 152, 178, 0, 0, 0, 0, 0},
{69, "", 7, 0, 125, 194, 0, 0, 0, 0, 0},
{70, "", 7, -9, 152, 178, 0, 0, 0, 0, 0},
{71, "", 7, 11, 114, 195, 0, 0, 0, 0, 0},
{72, "", 7, -12, 130, 190, 0, 0, 0, 0, 0},
{73, "NAD_Michigan", 8, -8, 160, 176, 0, 0, 0, 0, 0},
{75, "", 4, -425, -169, 81, 0, 0, 0, 0, 0},
{76, "", 22, -130, 110, -13, 0, 0, 0, 0, 0},
{77, "", 7, 61, -285, -181, 0, 0, 0, 0, 0},
{78, "", 6, -346, -1, 224, 0, 0, 0, 0, 0},
{79, "OSGB_1936", 9, 375, -111, 431, 0, 0, 0, 0, 0},
{80, "", 4, -307, -92, 127, 0, 0, 0, 0, 0},
{81, "", 4, 185, 165, 42, 0, 0, 0, 0, 0},
{82, "", 4, -288, 175, -376, 0, 0, 0, 0, 0},
{83, "Provisional_South_Americian_Datum_1956", 7, 11, 72, -101, 0, 0, 0, 0, 0},
{84, "", 4, -128, -283, 22, 0, 0, 0, 0, 0},
{85, "Qornoq", 4, 164, 138, -189, 0, 0, 0, 0, 0},
{86, "", 4, 94, -948, -1262, 0, 0, 0, 0, 0},
{87, "", 4, -225, -65, 9, 0, 0, 0, 0, 0},
{88, "", 4, 170, 42, 84, 0, 0, 0, 0, 0},
{89, "", 4, -203, 141, 53, 0, 0, 0, 0, 0},
{90, "Sapper_Hill_1943", 4, -355, 16, 74, 0, 0, 0, 0, 0},
{91, "Schwarzeck", 14, 616, 97, -251, 0, 0, 0, 0, 0},
{92, "South_American_Datum_1969", 24, -57, 1, -41, 0, 0, 0, 0, 0},
{93, "", 19, 7, -10, -26, 0, 0, 0, 0, 0},
{94, "", 4, -499, -249, 314, 0, 0, 0, 0, 0},
{95, "", 4, -104, 167, -38, 0, 0, 0, 0, 0},
{96, "Timbalai_1948", 11, -689, 691, -46, 0, 0, 0, 0, 0},
{97, "Tokyo", 10, -128, 481, 664, 0, 0, 0, 0, 0},
{98, "", 4, -632, 438, -609, 0, 0, 0, 0, 0},
{99, "", 6, 51, 391, -36, 0, 0, 0, 0, 0},
{100, "", 23, 101, 52, -39, 0, 0, 0, 0, 0},
{101, "", 26, 0, 0, 0, 0, 0, 0, 0, 0},
{102, "", 27, 0, 0, 0, 0, 0, 0, 0, 0},
{104, "WGS_1984", 28, 0, 0, 0, 0, 0, 0, 0, 0},
{103, "WGS_1972", 1, 0, 8, 10, 0, 0, 0, 0, 0},
{105, "Yacare", 4, -155, 171, 37, 0, 0, 0, 0, 0},
{106, "Zanderij", 4, -265, 120, -358, 0, 0, 0, 0, 0},
{107, "Nouvelle_Triangulation_Francaise", 30, -168, -60, 320, 0, 0, 0, 0, 0},
{108, "European_Datum_1987", 4, -83, -96, -113, 0, 0, 0, 0, 0},
{109, "", 10, 593, 26, 478, 0, 0, 0, 0, 0},
{110, "", 4, 81, 120, 129, 0, 0, 0, 0, 0},
{111, "", 1, -1, 15, 1, 0, 0, 0, 0, 0},
{112, "", 10, 498, -36, 568, 0, 0, 0, 0, 0},
{113, "", 4, -303, -62, 105, 0, 0, 0, 0, 0},
{114, "", 4, -223, 110, 37, 0, 0, 0, 0, 0},
{-1, NULL, 0, 0, 0, 0, 0, 0, 0, 0}
};

/* -------------------------------------------------------------------- */
/*      This table was hand entered from Appendix G of the map info     */
/*      manuals.                                                        */
/* -------------------------------------------------------------------- */
MapInfoSpheroidInfo asSpheroidInfoList[] =
{
    {9,"Airy 1930",				6377563.396,299.3249646},
    {13,"Airy 1930 (modified for Ireland 1965",	6377340.189,299.3249646},
    {2,"Australian",				6378160.0,  298.25},
    {10,"Bessel 1841",                          6377397.155,299.1528128},
    {14,"Bessel 1841 (modified for Schwarzeck)",6377483.865,299.1528128},
    {35,"Bessel 1841 (modified for NGO 1948)",  6377492.0176,299.15281},
    {36,"Clarke 1858",				6378293.639,294.26068},
    {7, "Clarke 1866",                          6378206.4,  294.9786982},
    {8, "Clarke 1866 (modified for Michigan)",  6378450.047484481,294.9786982},
    {6, "Clarke 1880",    			6378249.145, 293.465},
    {15,"Clarke 1880 (modified for Arc 1950)",  6378249.145326, 293.4663076},
    {30,"Clarke 1880 (modified for IGN)",       6378249.2,  293.4660213},
    {37,"Clarke 1880 (modified for Jamaica)",   6378249.136, 293.46631},
    {16,"Clarke 1880 (modified for Merchich)",  6378249.2, 293.46598},
    {38,"Clarke 1880 (modified for Palestine)", 6378300.79, 293.46623},
    {11,"Everest 1830",                         6377276.345, 300.8017},
    {40,"Everest 1830 (modified for Kalianpur)",6377301.243, 300.80174},
    {17,"Everest 1830 (modified for Kertau)",   6377304.063, 300.8017},
    {39,"Everest 1830 (modified for Timbalai)", 6377298.556, 300.8017},
    {18,"Fischer 1960",                         6378166.0,   298.3},
    {19,"Fischer 1960 (modified for South Asia)",6378155.0,  298.3},
    {20,"Fischer 1968",                         6378150.0,   298.3},
    {21,"GRS 67",                               6378160.0,   298.247167427},
    {0, "GRS 80",                               6378137.0,   298.257222101},
    {5, "Hayford",                              6378388.0,   297.0},
    {22,"Helmert 1906",                         6378200.0,   298.3},
    {23,"Hough",                                6378270.0,   297.0},
    {31,"IAG 75",                               6378140.0,   298.257222},
    {41,"Indonesian",                           6378160.0,   298.247},
    {4, "International 1924",                   6378388.0,   297.0},
    {3, "Krassovsky",                           6378245.0,   298.3},
    {32,"MERIT 83",                             6378137.0,   298.257},
    {33,"New International 1967",               6378157.5,   298.25},
    {42,"NWL 9D",                               6378145.0,   298.25},
    {43,"NWL 10D",                              6378135.0,   298.26},
    {44,"OSU86F",                               6378136.2,   298.25722},
    {45,"OSU91A",                               6378136.3,   298.25722},
    {46,"Plessis 1817",                         6376523.0,   308.64},
    {24,"South American",                       6378160.0,   298.25},
    {12,"Sphere",                               6370997.0,     0.0},
    {47,"Struve 1860",                          6378297.0,   294.73},
    {34,"Walbeck",                              6376896.0,   302.78},
    {25,"War Office",                           6378300.583, 296.0},
    {26,"WGS 60",                               6378165.0,   298.3},
    {27,"WGS 66",                               6378145.0,   298.25},
    {1, "WGS 72",                               6378135.0,   298.26},
    {28,"WGS 84",                               6378137.0,   298.257223563},
    {29,"WGS 84 (MAPINFO Datum 0)",             6378137.01,  298.257223563},
    {-1,NULL,                                   0.0,         0.0}
};
 
/**********************************************************************
 *                   TABFile::GetSpatialRef()
 *
 * Returns a reference to an OGRSpatialReference for this dataset.
 * If the projection parameters have not been parsed yet, then we will
 * parse them before returning.
 *
 * The returned object is owned and maintained by this TABFile and
 * should not be modified or freed by the caller.
 *
 * Returns NULL if the SpatialRef cannot be accessed.
 **********************************************************************/
OGRSpatialReference *TABFile::GetSpatialRef()
{
    if (m_eAccessMode != TABRead)
    {
        CPLError(CE_Failure, CPLE_NotSupported,
                 "GetSpatialRef() can be used only with Read access.");
        return NULL;
    }
 
    if (m_poMAPFile == NULL )
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
                 "GetSpatialRef() failed: file has not been opened yet.");
        return NULL;
    }

    /*-----------------------------------------------------------------
     * If projection params have already been processed, just use them.
     *----------------------------------------------------------------*/
    if (m_poSpatialRef != NULL)
        return m_poSpatialRef;
    

    /*-----------------------------------------------------------------
     * Fetch the parameters from the header.
     *----------------------------------------------------------------*/
    TABMAPHeaderBlock *poHeader;
    TABProjInfo     sTABProj;

    if ((poHeader = m_poMAPFile->GetHeaderBlock()) == NULL ||
        poHeader->GetProjInfo( &sTABProj ) != 0)
    {
        CPLError(CE_Failure, CPLE_FileIO,
                 "GetSpatialRef() failed reading projection parameters.");
        return NULL;
    }

    /*-----------------------------------------------------------------
     * Transform them into an OGRSpatialReference.
     *----------------------------------------------------------------*/
    m_poSpatialRef = new OGRSpatialReference;

    /*-----------------------------------------------------------------
     * Handle the PROJCS style projections, but add the datum later.
     *----------------------------------------------------------------*/
    switch( sTABProj.nProjId )
    {
        /*--------------------------------------------------------------
         * NonEarth ... we return with an empty SpatialRef.  Eventually
         * we might want to include the units, but not for now.
         *-------------------------------------------------------------*/
      case 0:
        return m_poSpatialRef;
        break;

        /*--------------------------------------------------------------
         * lat/long .. just add the GEOGCS later.
         *-------------------------------------------------------------*/
      case 1:
        break;

        /*--------------------------------------------------------------
         * Cylindrical Equal Area
         *-------------------------------------------------------------*/
      case 2:
        m_poSpatialRef->SetCEA( sTABProj.adProjParams[1],
                                sTABProj.adProjParams[0],
                                sTABProj.adProjParams[2],
                                sTABProj.adProjParams[3] );
        break;

        /*--------------------------------------------------------------
         * Lambert Conic Conformal
         *-------------------------------------------------------------*/
      case 3:
        m_poSpatialRef->SetLCC( sTABProj.adProjParams[2],
                                sTABProj.adProjParams[3],
                                sTABProj.adProjParams[1],
                                sTABProj.adProjParams[0],
                                sTABProj.adProjParams[4],
                                sTABProj.adProjParams[5] );
        break;

        /*--------------------------------------------------------------
         * Lambert Azimuthal Equal Area
         *-------------------------------------------------------------*/
      case 4:
        m_poSpatialRef->SetLAEA( sTABProj.adProjParams[1],
                                 sTABProj.adProjParams[0],
                                 0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Azimuthal Equidistant (Polar aspect only)
         *-------------------------------------------------------------*/
      case 5:
        m_poSpatialRef->SetAE( sTABProj.adProjParams[1],
                               sTABProj.adProjParams[0],
                               0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Equidistant Conic
         *-------------------------------------------------------------*/
      case 6:
        m_poSpatialRef->SetEC( sTABProj.adProjParams[2],
                               sTABProj.adProjParams[3],
                               sTABProj.adProjParams[1],
                               sTABProj.adProjParams[0],
                               sTABProj.adProjParams[4],
                               sTABProj.adProjParams[5] );
        break;

        /*--------------------------------------------------------------
         * Hotine Oblique Mercator
         *-------------------------------------------------------------*/
      case 7:
        m_poSpatialRef->SetHOM( sTABProj.adProjParams[1],
                                sTABProj.adProjParams[0], 
                                sTABProj.adProjParams[2],
                                90.0, 
                                sTABProj.adProjParams[3],
                                sTABProj.adProjParams[4],
                                sTABProj.adProjParams[5] );
        break;

        /*--------------------------------------------------------------
         * Albers Conic Equal Area
         *-------------------------------------------------------------*/
      case 9:
        m_poSpatialRef->SetACEA( sTABProj.adProjParams[2],
                                 sTABProj.adProjParams[3],
                                 sTABProj.adProjParams[1],
                                 sTABProj.adProjParams[0],
                                 sTABProj.adProjParams[4],
                                 sTABProj.adProjParams[5] );
        break;

        /*--------------------------------------------------------------
         * Mercator
         *-------------------------------------------------------------*/
      case 10:
        m_poSpatialRef->SetMercator( 0.0, sTABProj.adProjParams[0],
                                     1.0, 0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Miller Cylindrical
         *-------------------------------------------------------------*/
      case 11:
        m_poSpatialRef->SetMC( 0.0, sTABProj.adProjParams[0],
                               0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Robinson
         *-------------------------------------------------------------*/
      case 12:
        m_poSpatialRef->SetRobinson( sTABProj.adProjParams[0],
                                     0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Mollweide
         *-------------------------------------------------------------*/
      case 13:
        m_poSpatialRef->SetMollweide( sTABProj.adProjParams[0],
                                      0.0, 0.0 );

        /*--------------------------------------------------------------
         * Eckert IV
         *-------------------------------------------------------------*/
      case 14:
        m_poSpatialRef->SetEckertIV( sTABProj.adProjParams[0], 0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Eckert VI
         *-------------------------------------------------------------*/
      case 15:
        m_poSpatialRef->SetEckertVI( sTABProj.adProjParams[0], 0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Sinusoidal
         *-------------------------------------------------------------*/
      case 16:
        m_poSpatialRef->SetSinusoidal( sTABProj.adProjParams[0],
                                       0.0, 0.0 );
        break;

        /*--------------------------------------------------------------
         * Transverse Mercator
         *-------------------------------------------------------------*/
      case 8:
      case 21:
      case 22:
      case 23:
      case 24:
        m_poSpatialRef->SetTM( sTABProj.adProjParams[1],
                               sTABProj.adProjParams[0],
                               sTABProj.adProjParams[2],
                               sTABProj.adProjParams[3],
                               sTABProj.adProjParams[4] );
        break;

        /*--------------------------------------------------------------
         * Gall Stereographic
         *-------------------------------------------------------------*/
      case 17:
        m_poSpatialRef->SetGS( sTABProj.adProjParams[0], 0.0, 0.0 );
        break;
        
        /*--------------------------------------------------------------
         * New Zealand Map Grid
         *-------------------------------------------------------------*/
      case 18:
        m_poSpatialRef->SetNZMG( sTABProj.adProjParams[1],
                                 sTABProj.adProjParams[0],
                                 sTABProj.adProjParams[2],
                                 sTABProj.adProjParams[3] );
        break;

        /*--------------------------------------------------------------
         * Lambert Conic Conformal (Belgium)
         *-------------------------------------------------------------*/
      case 19:
        m_poSpatialRef->SetLCCB( sTABProj.adProjParams[2],
                                 sTABProj.adProjParams[3],
                                 sTABProj.adProjParams[1],
                                 sTABProj.adProjParams[0],
                                 sTABProj.adProjParams[4],
                                 sTABProj.adProjParams[5] );
        break;

        /*--------------------------------------------------------------
         * Stereographic
         *-------------------------------------------------------------*/
      case 20:
        m_poSpatialRef->SetStereographic( sTABProj.adProjParams[1],
                                          sTABProj.adProjParams[0],
                                          sTABProj.adProjParams[2],
                                          sTABProj.adProjParams[3],
                                          sTABProj.adProjParams[4] );
        break;

      default:
        break;
    }

    /*-----------------------------------------------------------------
     * Collect units definition.
     *----------------------------------------------------------------*/
    if( sTABProj.nProjId != 1 && m_poSpatialRef->GetRoot() != NULL )
    {
        OGR_SRSNode	*poUnits = new OGR_SRSNode("UNIT");
        
        m_poSpatialRef->GetRoot()->AddChild(poUnits);

        poUnits->AddChild( new OGR_SRSNode( SRS_UL_METER ) );
        poUnits->AddChild( new OGR_SRSNode( "1.0" ) );
       
        switch( sTABProj.nUnitsId )
        {
          case 0:
            poUnits->GetChild(0)->SetValue("Mile");
            poUnits->GetChild(1)->SetValue("1609.344");
            break;

          case 1:
            poUnits->GetChild(0)->SetValue("Kilometer");
            poUnits->GetChild(1)->SetValue("1000.0");
            break;
            
          case 2:
            poUnits->GetChild(0)->SetValue("IINCH");
            poUnits->GetChild(1)->SetValue("0.0254");
            break;
            
          case 3:
            poUnits->GetChild(0)->SetValue(SRS_UL_FOOT);
            poUnits->GetChild(1)->SetValue(SRS_UL_FOOT_CONV);
            break;
            
          case 4:
            poUnits->GetChild(0)->SetValue("IYARD");
            poUnits->GetChild(1)->SetValue("0.9144");
            break;
            
          case 5:
            poUnits->GetChild(0)->SetValue("Millimeter");
            poUnits->GetChild(1)->SetValue("0.001");
            break;
            
          case 6:
            poUnits->GetChild(0)->SetValue("Centimeter");
            poUnits->GetChild(1)->SetValue("0.01");
            break;
            
          case 7:
            poUnits->GetChild(0)->SetValue(SRS_UL_METER);
            poUnits->GetChild(1)->SetValue("1.0");
            break;
            
          case 8:
            poUnits->GetChild(0)->SetValue(SRS_UL_US_FOOT);
            poUnits->GetChild(1)->SetValue(SRS_UL_US_FOOT_CONV);
            break;
            
          case 9:
            poUnits->GetChild(0)->SetValue(SRS_UL_NAUTICAL_MILE);
            poUnits->GetChild(1)->SetValue(SRS_UL_NAUTICAL_MILE_CONV);
            break;
            
          case 30:
            poUnits->GetChild(0)->SetValue(SRS_UL_LINK);
            poUnits->GetChild(1)->SetValue(SRS_UL_LINK_CONV);
            break;
            
          case 31:
            poUnits->GetChild(0)->SetValue(SRS_UL_CHAIN);
            poUnits->GetChild(1)->SetValue(SRS_UL_CHAIN_CONV);
            break;
            
          case 32:
            poUnits->GetChild(0)->SetValue(SRS_UL_ROD);
            poUnits->GetChild(1)->SetValue(SRS_UL_ROD_CONV);
            break;
            
          default:
            break;
        }
    }

    /*-----------------------------------------------------------------
     * Set the datum.  We are only given the X, Y and Z shift for
     * the datum, so for now we just synthesize a name from this.
     * It would be better if we could lookup a name based on the shift.
     *----------------------------------------------------------------*/
    char	szDatumName[128];
    int		iDatumInfo;
    MapInfoDatumInfo *psDatumInfo;

    for( iDatumInfo = 0;
         asDatumInfoList[iDatumInfo].nMapInfoDatumID != -1;
         iDatumInfo++ )
    {
        psDatumInfo = asDatumInfoList + iDatumInfo;
        
        if( psDatumInfo->nEllipsoid == sTABProj.nEllipsoidId
            && psDatumInfo->dfShiftX == sTABProj.dDatumShiftX
            && psDatumInfo->dfShiftY == sTABProj.dDatumShiftY
            && psDatumInfo->dfShiftZ == sTABProj.dDatumShiftZ
            && psDatumInfo->dfDatumParm0 == sTABProj.adDatumParams[0]
            && psDatumInfo->dfDatumParm1 == sTABProj.adDatumParams[1]
            && psDatumInfo->dfDatumParm2 == sTABProj.adDatumParams[2]
            && psDatumInfo->dfDatumParm3 == sTABProj.adDatumParams[3]
            && psDatumInfo->dfDatumParm4 == sTABProj.adDatumParams[4] )
            break;

        psDatumInfo = NULL;
    }

    if( psDatumInfo == NULL )
    {
        if( sTABProj.adDatumParams[0] == 0.0
            && sTABProj.adDatumParams[1] == 0.0
            && sTABProj.adDatumParams[2] == 0.0
            && sTABProj.adDatumParams[3] == 0.0
            && sTABProj.adDatumParams[4] == 0.0 )
        {
            sprintf( szDatumName,
                     "MIF 999,%d,%.4g,%.4g,%.4g",
                     sTABProj.nEllipsoidId,
                     sTABProj.dDatumShiftX, 
                     sTABProj.dDatumShiftY, 
                     sTABProj.dDatumShiftZ );
        }
        else
        {
            sprintf( szDatumName,
                    "MIF 9999,%d,%.4g,%.4g,%.4g,%.15g,%.15g,%.15g,%.15g,%.15g",
                     sTABProj.nEllipsoidId,
                     sTABProj.dDatumShiftX, 
                     sTABProj.dDatumShiftY, 
                     sTABProj.dDatumShiftZ,
                     sTABProj.adDatumParams[0],
                     sTABProj.adDatumParams[1],
                     sTABProj.adDatumParams[2],
                     sTABProj.adDatumParams[3],
                     sTABProj.adDatumParams[4] );
        }

        poHeader->SetProjInfo( &sTABProj );
    }
    else if( strlen(psDatumInfo->pszOGCDatumName) > 0 )
    {
        strncpy( szDatumName, psDatumInfo->pszOGCDatumName,
                 sizeof(szDatumName) );

        poHeader->SetProjInfo( &sTABProj );
    }
    else
    {
        sprintf( szDatumName, "MIF %d", psDatumInfo->nMapInfoDatumID );
        
        poHeader->SetProjInfo( &sTABProj );
    }

    /*-----------------------------------------------------------------
     * Set the spheroid.
     *----------------------------------------------------------------*/
    double	dfSemiMajor, dfInvFlattening;
    const char *pszSpheroidName = NULL;

    for( int i = 0; asSpheroidInfoList[i].nMapInfoId != -1; i++ )
    {
        if( asSpheroidInfoList[i].nMapInfoId == sTABProj.nEllipsoidId )
        {
            dfSemiMajor = asSpheroidInfoList[i].dfA;
            dfInvFlattening = asSpheroidInfoList[i].dfInvFlattening;
            pszSpheroidName = asSpheroidInfoList[i].pszMapinfoName;
            break;
        }
    }

    // use WGS 84 if nothing is known.
    if( pszSpheroidName == NULL )
    {
        pszSpheroidName = "unknown";
        dfSemiMajor = 6378137.0;
        dfInvFlattening = 298.257223563;
    }

    /*-----------------------------------------------------------------
     * Set the prime meridian.
     *----------------------------------------------------------------*/
    double	dfPMOffset = 0.0;
    const char *pszPMName = "Greenwich";
    
    if( sTABProj.adDatumParams[4] != 0.0 )
    {
        dfPMOffset = sTABProj.adDatumParams[4];

        pszPMName = "non-Greenwich";
    }
                    
    /*-----------------------------------------------------------------
     * Create a GEOGCS definition.
     *----------------------------------------------------------------*/

    m_poSpatialRef->SetGeogCS( "unnamed",
                               szDatumName,
                               pszSpheroidName,
                               dfSemiMajor, dfInvFlattening,
                               pszPMName, dfPMOffset,
                               SRS_UA_DEGREE, atof(SRS_UA_DEGREE_CONV));

    return m_poSpatialRef;
}

/**********************************************************************
 *                   TABFile::SetSpatialRef()
 *
 * Set the OGRSpatialReference for this dataset.
 * A reference to the OGRSpatialReference will be kept, and it will also
 * be converted into a TABProjInfo to be stored in the .MAP header.
 *
 * Returns 0 on success, and -1 on error.
 **********************************************************************/
int TABFile::SetSpatialRef(OGRSpatialReference *poSpatialRef)
{
    if (m_eAccessMode != TABWrite)
    {
        CPLError(CE_Failure, CPLE_NotSupported,
                 "SetSpatialRef() can be used only with Write access.");
        return -1;
    }

    if (m_poMAPFile == NULL )
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
                 "SetSpatialRef() failed: file has not been opened yet.");
        return -1;
    }

    /*-----------------------------------------------------------------
     * Keep a copy of the OGRSpatialReference...
     * Note: we have to take the reference count into account...
     *----------------------------------------------------------------*/
    if (m_poSpatialRef && m_poSpatialRef->Dereference() == 0)
        delete m_poSpatialRef;
    
    m_poSpatialRef = poSpatialRef;
    m_poSpatialRef->Reference();

    /*-----------------------------------------------------------------
     * Initialize TABProjInfo
     *----------------------------------------------------------------*/
    TABProjInfo     sTABProj;

    sTABProj.nProjId = 0;
    sTABProj.nEllipsoidId = 0; /* how will we set this? */
    sTABProj.nUnitsId = 7;
    sTABProj.adProjParams[0] = sTABProj.adProjParams[1] = 0.0;
    sTABProj.adProjParams[2] = sTABProj.adProjParams[3] = 0.0;
    sTABProj.adProjParams[4] = sTABProj.adProjParams[5] = 0.0;
    
    sTABProj.dDatumShiftX = 0.0;
    sTABProj.dDatumShiftY = 0.0;
    sTABProj.dDatumShiftZ = 0.0;
    sTABProj.adDatumParams[0] = 0.0;
    sTABProj.adDatumParams[1] = 0.0;
    sTABProj.adDatumParams[2] = 0.0;
    sTABProj.adDatumParams[3] = 0.0;
    sTABProj.adDatumParams[4] = 0.0;
    
    /*-----------------------------------------------------------------
     * Transform the projection and projection parameters.
     *----------------------------------------------------------------*/
    const char *pszProjection = poSpatialRef->GetAttrValue("PROJECTION");
    double	*parms = sTABProj.adProjParams;

    if( pszProjection == NULL )
    {
        sTABProj.nProjId = 1;
    }
    else if( EQUAL(pszProjection,SRS_PT_ALBERS_CONIC_EQUAL_AREA) )
    {
        sTABProj.nProjId = 9;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_CENTER,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_1,0.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_2,0.0);
        parms[4] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[5] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_AZIMUTHAL_EQUIDISTANT) )
    {
        sTABProj.nProjId = 5;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_CENTER,0.0);
        parms[2] = 90.0;
    }

    else if( EQUAL(pszProjection,SRS_PT_CYLINDRICAL_EQUAL_AREA) )
    {
        sTABProj.nProjId = 2;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_1,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_ECKERT_IV) )
    {
        sTABProj.nProjId = 14;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_ECKERT_VI) )
    {
        sTABProj.nProjId = 15;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_EQUIDISTANT_CONIC) )
    {
        sTABProj.nProjId = 6;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_CENTER,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_1,0.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_2,0.0);
        parms[4] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[5] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_GALL_STEREOGRAPHIC) )
    {
        sTABProj.nProjId = 17;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_HOTINE_OBLIQUE_MERCATOR) )
    {
        sTABProj.nProjId = 7;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_CENTER,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_AZIMUTH,0.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_SCALE_FACTOR,1.0);
        parms[4] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[5] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_LAMBERT_AZIMUTHAL_EQUAL_AREA) )
    {
        sTABProj.nProjId = 4;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_CENTER,0.0);
        parms[2] = 90.0;
    }

    else if( EQUAL(pszProjection,SRS_PT_LAMBERT_CONFORMAL_CONIC_2SP) )
    {
        sTABProj.nProjId = 3;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_1,0.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_STANDARD_PARALLEL_2,0.0);
        parms[4] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[5] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_MERCATOR_1SP) )
    {
        sTABProj.nProjId = 10;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_SCALE_FACTOR,1.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_MILLER_CYLINDRICAL) )
    {
        sTABProj.nProjId = 11;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_MOLLWEIDE) )
    {
        sTABProj.nProjId = 13;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_NEW_ZEALAND_MAP_GRID) )
    {
        sTABProj.nProjId = 18;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_ROBINSON) )
    {
        sTABProj.nProjId = 12;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_SINUSOIDAL) )
    {
        sTABProj.nProjId = 16;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_STEREOGRAPHIC) )
    {
        sTABProj.nProjId = 20;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_SCALE_FACTOR,1.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[4] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    else if( EQUAL(pszProjection,SRS_PT_TRANSVERSE_MERCATOR) )
    {
        sTABProj.nProjId = 8;
        parms[0] = poSpatialRef->GetProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0);
        parms[1] = poSpatialRef->GetProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0);
        parms[2] = poSpatialRef->GetProjParm(SRS_PP_SCALE_FACTOR,1.0);
        parms[3] = poSpatialRef->GetProjParm(SRS_PP_FALSE_EASTING,0.0);
        parms[4] = poSpatialRef->GetProjParm(SRS_PP_FALSE_NORTHING,0.0);
    }

    /* ==============================================================
     * Translate Datum and Ellipsoid
     * ============================================================== */
    const char *pszWKTDatum = poSpatialRef->GetAttrValue("DATUM");
    MapInfoDatumInfo *psDatumInfo = NULL;
    
    /*-----------------------------------------------------------------
     * Default to WGS83 if we have no datum at all.
     *----------------------------------------------------------------*/
    if( pszWKTDatum == NULL )
    {
        psDatumInfo = asDatumInfoList+0; /* WGS 84 */
    }
    
    /*-----------------------------------------------------------------
     * We know the MIF datum number, and need to look it up to
     * translate into datum parameters.
     *----------------------------------------------------------------*/
    else if( EQUALN(pszWKTDatum,"MIF ",4)
             && atoi(pszWKTDatum+4) != 999
             && atoi(pszWKTDatum+4) != 9999 )
    {
        int	i;

        for( i = 0; asDatumInfoList[i].nMapInfoDatumID != -1; i++ )
        {
            if( atoi(pszWKTDatum+4) == asDatumInfoList[i].nMapInfoDatumID )
            {
                psDatumInfo = asDatumInfoList + i;
                break;
            }
        }

        if( psDatumInfo == NULL )
            psDatumInfo = asDatumInfoList+0; /* WGS 84 */
    }

    /*-----------------------------------------------------------------
     * We have the MIF datum parameters, and apply those directly.
     *----------------------------------------------------------------*/
    else if( EQUALN(pszWKTDatum,"MIF ",4)
             && (atoi(pszWKTDatum+4) == 999 || atoi(pszWKTDatum+4) == 9999) )
    {
        char **papszFields;

        papszFields =
            CSLTokenizeStringComplex( pszWKTDatum+4, ",", FALSE, TRUE);

        if( CSLCount(papszFields) >= 5 )
        {
            sTABProj.nEllipsoidId = atoi(papszFields[1]);
            sTABProj.dDatumShiftX = atof(papszFields[2]);
            sTABProj.dDatumShiftY = atof(papszFields[3]);
            sTABProj.dDatumShiftZ = atof(papszFields[4]);
        }

        if( CSLCount(papszFields) >= 10 )
        {
            sTABProj.adDatumParams[0] = atof(papszFields[4]);
            sTABProj.adDatumParams[1] = atof(papszFields[5]);
            sTABProj.adDatumParams[2] = atof(papszFields[6]);
            sTABProj.adDatumParams[3] = atof(papszFields[7]);
            sTABProj.adDatumParams[4] = atof(papszFields[8]);
        }

        CSLDestroy( papszFields );

        if( CSLCount(papszFields) < 5 )
            psDatumInfo = asDatumInfoList+0; /* WKS84 */
    }
    
    /*-----------------------------------------------------------------
     * We have a "real" datum name.  Try to look it up and get the
     * parameters.  If we don't find it just use WGS84.
     *----------------------------------------------------------------*/
    else 
    {
        int	i;

        for( i = 0; asDatumInfoList[i].nMapInfoDatumID != -1; i++ )
        {
            if( EQUAL(pszWKTDatum,asDatumInfoList[i].pszOGCDatumName) )
            {
                psDatumInfo = asDatumInfoList + i;
                break;
            }
        }

         if( psDatumInfo == NULL )
            psDatumInfo = asDatumInfoList+0; /* WGS 84 */
    }

    if( psDatumInfo != NULL )
    {
        sTABProj.nEllipsoidId = psDatumInfo->nEllipsoid;
        sTABProj.dDatumShiftX = psDatumInfo->dfShiftX;
        sTABProj.dDatumShiftY = psDatumInfo->dfShiftY;
        sTABProj.dDatumShiftZ = psDatumInfo->dfShiftZ;
        sTABProj.adDatumParams[0] = psDatumInfo->dfDatumParm0;
        sTABProj.adDatumParams[1] = psDatumInfo->dfDatumParm1;
        sTABProj.adDatumParams[2] = psDatumInfo->dfDatumParm2;
        sTABProj.adDatumParams[3] = psDatumInfo->dfDatumParm3;
        sTABProj.adDatumParams[4] = psDatumInfo->dfDatumParm4;
    }
    
    /*-----------------------------------------------------------------
     * Translate the units
     *----------------------------------------------------------------*/
    char 	*pszLinearUnits;
    double      dfLinearConv;

    dfLinearConv = poSpatialRef->GetLinearUnits( &pszLinearUnits );

    if( sTABProj.nProjId == 1 || pszLinearUnits == NULL )
        sTABProj.nUnitsId = 13;
    else if( dfLinearConv == 1000.0 )
        sTABProj.nUnitsId = 1;
    else if( dfLinearConv == 0.0254 )
        sTABProj.nUnitsId = 2;
    else if( EQUAL(pszLinearUnits,SRS_UL_FOOT) )
        sTABProj.nUnitsId = 3;
    else if( EQUAL(pszLinearUnits,"IYARD") || dfLinearConv == 0.9144 )
        sTABProj.nUnitsId = 4;
    else if( dfLinearConv == 0.001 )
        sTABProj.nUnitsId = 5;
    else if( dfLinearConv == 0.01 )
        sTABProj.nUnitsId = 6;
    else if( dfLinearConv == 1.0 )
        sTABProj.nUnitsId = 7;
    else if( EQUAL(pszLinearUnits,SRS_UL_US_FOOT) )
        sTABProj.nUnitsId = 8;
    else if( EQUAL(pszLinearUnits,SRS_UL_NAUTICAL_MILE) )
        sTABProj.nUnitsId = 9;
    else if( EQUAL(pszLinearUnits,SRS_UL_LINK) )
        sTABProj.nUnitsId = 30;
    else if( EQUAL(pszLinearUnits,SRS_UL_CHAIN) )
        sTABProj.nUnitsId = 31;
    else if( EQUAL(pszLinearUnits,SRS_UL_ROD) )
        sTABProj.nUnitsId = 32;
    else if( EQUAL(pszLinearUnits,"Mile") 
             || EQUAL(pszLinearUnits,"IMILE") )
        sTABProj.nUnitsId = 0;
    else
        sTABProj.nUnitsId = 7;
    
    /*-----------------------------------------------------------------
     * Set the new parameters in the .MAP header.
     *----------------------------------------------------------------*/
    TABMAPHeaderBlock *poHeader;

    if ((poHeader = m_poMAPFile->GetHeaderBlock()) == NULL ||
        poHeader->SetProjInfo( &sTABProj ) != 0)
    {
        CPLError(CE_Failure, CPLE_FileIO,
                 "SetSpatialRef() failed setting projection parameters.");
        return -1;
    }

    return 0;
}

