ogr_srs_proj4.cpp

mitab,读取MapInfo的地图文件

                 GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
    }
    
    else if( EQUAL(pszProjection,SRS_PT_LAMBERT_CONFORMAL_CONIC_1SP) )
    {
        sprintf( szProj4+strlen(szProj4),
                 "+proj=lcc +lat_1=%.16g +lat_0=%.16g +lon_0=%.16g"
                 " +k_0=%.16g +x_0=%.16g +y_0=%.16g ",
                 GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                 GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                 GetNormProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0),
                 GetNormProjParm(SRS_PP_SCALE_FACTOR,1.0),
                 GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                 GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
    }

    else if( EQUAL(pszProjection,SRS_PT_HOTINE_OBLIQUE_MERCATOR) )
    {
        /* not clear how ProjParm[3] - angle from rectified to skewed grid -
           should be applied ... see the +not_rot flag for PROJ.4.
           Just ignoring for now. */

        /* special case for swiss oblique mercator : see bug 423 */
        if( fabs(GetNormProjParm(SRS_PP_AZIMUTH,0.0) - 90.0) < 0.0001 
            && fabs(GetNormProjParm(SRS_PP_RECTIFIED_GRID_ANGLE,0.0)-90.0) < 0.0001 )
        {
            sprintf( szProj4+strlen(szProj4),
                     "+proj=somerc +lat_0=%.16g +lon_0=%.16g"
                     " +x_0=%.16g +y_0=%.16g ",
                     GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                     GetNormProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0),
                     GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                     GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
        }
        else
        {
            sprintf( szProj4+strlen(szProj4),
                     "+proj=omerc +lat_0=%.16g +lonc=%.16g +alpha=%.16g"
                     " +k=%.16g +x_0=%.16g +y_0=%.16g ",
                     GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                     GetNormProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0),
                     GetNormProjParm(SRS_PP_AZIMUTH,0.0),
                     GetNormProjParm(SRS_PP_SCALE_FACTOR,1.0),
                     GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                     GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
        }
    }

    else if( EQUAL(pszProjection,
                   SRS_PT_HOTINE_OBLIQUE_MERCATOR_TWO_POINT_NATURAL_ORIGIN) )
    {
        sprintf( szProj4+strlen(szProj4),
                 "+proj=omerc +lat_0=%.16g"
                 " +lon_1=%.16g +lat_1=%.16g +lon_2=%.16g +lat_2=%.16g"
                 " +k=%.16g +x_0=%.16g +y_0=%.16g ",
                 GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                 GetNormProjParm(SRS_PP_LATITUDE_OF_POINT_1,0.0),
                 GetNormProjParm(SRS_PP_LONGITUDE_OF_POINT_1,0.0),
                 GetNormProjParm(SRS_PP_LATITUDE_OF_POINT_2,0.0),
                 GetNormProjParm(SRS_PP_LONGITUDE_OF_POINT_2,0.0),
                 GetNormProjParm(SRS_PP_SCALE_FACTOR,1.0),
                 GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                 GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
    }

    else if( EQUAL(pszProjection,SRS_PT_KROVAK) )
    {
        sprintf( szProj4+strlen(szProj4),
                 "+proj=krovak +lat_0=%.16g +lon_0=%.16g +alpha=%.16g"
                 " +k=%.16g +x_0=%.16g +y_0=%.16g ",
                 GetNormProjParm(SRS_PP_LATITUDE_OF_CENTER,0.0),
                 GetNormProjParm(SRS_PP_LONGITUDE_OF_CENTER,0.0),
                 GetNormProjParm(SRS_PP_AZIMUTH,0.0),
                 GetNormProjParm(SRS_PP_SCALE_FACTOR,1.0),
                 GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                 GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
    }

    else if( EQUAL(pszProjection,SRS_PT_TWO_POINT_EQUIDISTANT) )
    {
        sprintf( szProj4+strlen(szProj4),
                 "+proj=tpeqd +lat_1=%.16g +lon_1=%.16g "
                 "+lat_2=%.16g +lon_2=%.16g "
                 "+x_0=%.16g +y_0=%.16g ",
                 GetNormProjParm(SRS_PP_LATITUDE_OF_1ST_POINT,0.0),
                 GetNormProjParm(SRS_PP_LONGITUDE_OF_1ST_POINT,0.0),
                 GetNormProjParm(SRS_PP_LATITUDE_OF_2ND_POINT,0.0),
                 GetNormProjParm(SRS_PP_LONGITUDE_OF_2ND_POINT,0.0),
                 GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                 GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
    }

    /* Note: This never really gets used currently.  See bug 423 */
    else if( EQUAL(pszProjection,SRS_PT_SWISS_OBLIQUE_CYLINDRICAL) )
    {
        sprintf( szProj4+strlen(szProj4),
                 "+proj=somerc +lat_0=%.16g +lon_0=%.16g"
                 " +x_0=%.16g +y_0=%.16g ",
                 GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                 GetNormProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0),
                 GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                 GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
    }

/* -------------------------------------------------------------------- */
/*      Handle earth model.  For now we just always emit the user       */
/*      defined ellipsoid parameters.                                   */
/* -------------------------------------------------------------------- */
    double      dfSemiMajor = GetSemiMajor();
    double      dfInvFlattening = GetInvFlattening();
    const char  *pszPROJ4Ellipse = NULL;
    const char  *pszDatum = GetAttrValue("DATUM");

    if( ABS(dfSemiMajor-6378249.145) < 0.01
        && ABS(dfInvFlattening-293.465) < 0.0001 )
    {
        pszPROJ4Ellipse = "clrk80";     /* Clark 1880 */
    }
    else if( ABS(dfSemiMajor-6378245.0) < 0.01
             && ABS(dfInvFlattening-298.3) < 0.0001 )
    {
        pszPROJ4Ellipse = "krass";      /* Krassovsky */
    }
    else if( ABS(dfSemiMajor-6378388.0) < 0.01
             && ABS(dfInvFlattening-297.0) < 0.0001 )
    {
        pszPROJ4Ellipse = "intl";       /* International 1924 */
    }
    else if( ABS(dfSemiMajor-6378160.0) < 0.01
             && ABS(dfInvFlattening-298.25) < 0.0001 )
    {
        pszPROJ4Ellipse = "aust_SA";    /* Australian */
    }
    else if( ABS(dfSemiMajor-6377397.155) < 0.01
             && ABS(dfInvFlattening-299.1528128) < 0.0001 )
    {
        pszPROJ4Ellipse = "bessel";     /* Bessel 1841 */
    }
    else if( ABS(dfSemiMajor-6377483.865) < 0.01
             && ABS(dfInvFlattening-299.1528128) < 0.0001 )
    {
        pszPROJ4Ellipse = "bess_nam";   /* Bessel 1841 (Namibia / Schwarzeck)*/
    }
    else if( ABS(dfSemiMajor-6378160.0) < 0.01
             && ABS(dfInvFlattening-298.247167427) < 0.0001 )
    {
        pszPROJ4Ellipse = "GRS67";      /* GRS 1967 */
    }
    else if( ABS(dfSemiMajor-6378137) < 0.01
             && ABS(dfInvFlattening-298.257222101) < 0.000001 )
    {
        pszPROJ4Ellipse = "GRS80";      /* GRS 1980 */
    }
    else if( ABS(dfSemiMajor-6378206.4) < 0.01
             && ABS(dfInvFlattening-294.9786982) < 0.0001 )
    {
        pszPROJ4Ellipse = "clrk66";     /* Clarke 1866 */
    }
    else if( ABS(dfSemiMajor-6378206.4) < 0.01
             && ABS(dfInvFlattening-294.9786982) < 0.0001 )
    {
        pszPROJ4Ellipse = "mod_airy";   /* Modified Airy */
    }
    else if( ABS(dfSemiMajor-6377563.396) < 0.01
             && ABS(dfInvFlattening-299.3249646) < 0.0001 )
    {
        pszPROJ4Ellipse = "airy";       /* Modified Airy */
    }
    else if( ABS(dfSemiMajor-6378200) < 0.01
             && ABS(dfInvFlattening-298.3) < 0.0001 )
    {
        pszPROJ4Ellipse = "helmert";    /* Helmert 1906 */
    }
    else if( ABS(dfSemiMajor-6378155) < 0.01
             && ABS(dfInvFlattening-298.3) < 0.0001 )
    {
        pszPROJ4Ellipse = "fschr60m";   /* Modified Fischer 1960 */
    }
    else if( ABS(dfSemiMajor-6377298.556) < 0.01
             && ABS(dfInvFlattening-300.8017) < 0.0001 )
    {
        pszPROJ4Ellipse = "evrstSS";    /* Everest (Sabah & Sarawak) */
    }
    else if( ABS(dfSemiMajor-6378165.0) < 0.01
             && ABS(dfInvFlattening-298.3) < 0.0001 )
    {
        pszPROJ4Ellipse = "WGS60";      
    }
    else if( ABS(dfSemiMajor-6378145.0) < 0.01
             && ABS(dfInvFlattening-298.25) < 0.0001 )
    {
        pszPROJ4Ellipse = "WGS66";      
    }
    else if( ABS(dfSemiMajor-6378135.0) < 0.01
             && ABS(dfInvFlattening-298.26) < 0.0001 )
    {
        pszPROJ4Ellipse = "WGS72";      
    }
    else if( ABS(dfSemiMajor-6378137.0) < 0.01
             && ABS(dfInvFlattening-298.257223563) < 0.000001 )
    {
        pszPROJ4Ellipse = "WGS84";
    }
    else if( EQUAL(pszDatum,"North_American_Datum_1927") )
    {
//        pszPROJ4Ellipse = "clrk66:+datum=nad27"; /* NAD 27 */
        pszPROJ4Ellipse = "clrk66";
    }
    else if( EQUAL(pszDatum,"North_American_Datum_1983") )
    {
//        pszPROJ4Ellipse = "GRS80:+datum=nad83";       /* NAD 83 */
        pszPROJ4Ellipse = "GRS80";
    }
    
    if( pszPROJ4Ellipse == NULL )
        sprintf( szProj4+strlen(szProj4), "+a=%.16g +b=%.16g ",
                 GetSemiMajor(), GetSemiMinor() );
    else
        sprintf( szProj4+strlen(szProj4), "+ellps=%s ",
                 pszPROJ4Ellipse );

/* -------------------------------------------------------------------- */
/*      Translate the datum.                                            */
/* -------------------------------------------------------------------- */
    const char *pszPROJ4Datum = NULL;
    const OGR_SRSNode *poTOWGS84 = GetAttrNode( "TOWGS84" );
    char  szTOWGS84[256];
    int nEPSGDatum = -1;
    const char *pszAuthority;
    int nEPSGGeogCS = -1;
    const char *pszGeogCSAuthority;

    pszAuthority = GetAuthorityName( "DATUM" );

    if( pszAuthority != NULL && EQUAL(pszAuthority,"EPSG") )
        nEPSGDatum = atoi(GetAuthorityCode( "DATUM" ));

    pszGeogCSAuthority = GetAuthorityName( "GEOGCS" );

    if( pszGeogCSAuthority != NULL && EQUAL(pszGeogCSAuthority,"EPSG") )
        nEPSGGeogCS = atoi(GetAuthorityCode( "GEOGCS" ));

    if( pszDatum == NULL )
        /* nothing */;

    else if( EQUAL(pszDatum,SRS_DN_NAD27) || nEPSGDatum == 6267 )
        pszPROJ4Datum = "+datum=NAD27";

    else if( EQUAL(pszDatum,SRS_DN_NAD83) || nEPSGDatum == 6269 )
        pszPROJ4Datum = "+datum=NAD83";

    else if( EQUAL(pszDatum,SRS_DN_WGS84) || nEPSGDatum == 6326 )
        pszPROJ4Datum = "+datum=WGS84";

    else if( nEPSGDatum == 6314 )
        pszPROJ4Datum = "+datum=potsdam";

    else if( nEPSGDatum == 6272 )
        pszPROJ4Datum = "+datum=nzgd49";

    else if( poTOWGS84 != NULL )
    {
        if( poTOWGS84->GetChildCount() > 2
            && (poTOWGS84->GetChildCount() < 6 
                || EQUAL(poTOWGS84->GetChild(3)->GetValue(),"")
                && EQUAL(poTOWGS84->GetChild(4)->GetValue(),"")
                && EQUAL(poTOWGS84->GetChild(5)->GetValue(),"")
                && EQUAL(poTOWGS84->GetChild(6)->GetValue(),"")) )
        {
            sprintf( szTOWGS84, "+towgs84=%s,%s,%s",
                     poTOWGS84->GetChild(0)->GetValue(),
                     poTOWGS84->GetChild(1)->GetValue(),
                     poTOWGS84->GetChild(2)->GetValue() );
            pszPROJ4Datum = szTOWGS84;
        }
        else if( poTOWGS84->GetChildCount() > 6 )
        {
            sprintf( szTOWGS84, "+towgs84=%s,%s,%s,%s,%s,%s,%s",
                     poTOWGS84->GetChild(0)->GetValue(),
                     poTOWGS84->GetChild(1)->GetValue(),
                     poTOWGS84->GetChild(2)->GetValue(),
                     poTOWGS84->GetChild(3)->GetValue(),
                     poTOWGS84->GetChild(4)->GetValue(),
                     poTOWGS84->GetChild(5)->GetValue(),
                     poTOWGS84->GetChild(6)->GetValue() );
            pszPROJ4Datum = szTOWGS84;
        }
    }

    else if( nEPSGGeogCS != -1 )
    {
        double padfTransform[7];
        if( EPSGGetWGS84Transform( nEPSGGeogCS, padfTransform ) )
        {
            sprintf( szTOWGS84, "+towgs84=%f,%f,%f,%f,%f,%f,%f",
                     padfTransform[0],
                     padfTransform[1],
                     padfTransform[2],
                     padfTransform[3],
                     padfTransform[4],
                     padfTransform[5],
                     padfTransform[6] );
            pszPROJ4Datum = szTOWGS84;
        }
    }
    
    if( pszPROJ4Datum != NULL )
    {
        strcat( szProj4, pszPROJ4Datum );
        strcat( szProj4, " " );
    }

/* -------------------------------------------------------------------- */
/*      Is there prime meridian info to apply?                          */
/* -------------------------------------------------------------------- */
    if( poPRIMEM != NULL && poPRIMEM->GetChildCount() >= 2 
        && atof(poPRIMEM->GetChild(1)->GetValue()) != 0.0 )
    {
        const char *pszAuthority = GetAuthorityName( "PRIMEM" );
        char szPMValue[128];
        int  nCode = -1;

        if( pszAuthority != NULL && EQUAL(pszAuthority,"EPSG") )
            nCode = atoi(GetAuthorityCode( "PRIMEM" ));

        switch( nCode )
        {