// returned WKT string should be free by OGRFree or CPLFree
static char* get_wkt_of(int epsg_code) {
OGRSpatialReferenceH srs = OSRNewSpatialReference(NULL);
OSRImportFromEPSG(srs, epsg_code);
char* srs_wkt;
OSRExportToWkt(srs, &srs_wkt);
return srs_wkt;
}
char *msProjectionObj2OGCWKT( projectionObj *projection )
{
#if !defined(USE_GDAL) && !defined(USE_OGR)
msSetError(MS_OGRERR,
"Not implemented since neither OGR nor GDAL is enabled.",
"msProjectionObj2OGCWKT()");
return NULL;
#else /* defined USE_GDAL or USE_OGR */
OGRSpatialReferenceH hSRS;
char *pszWKT=NULL, *pszProj4, *pszInitEpsg=NULL;
int nLength = 0, i;
OGRErr eErr;
if( projection->proj == NULL )
return NULL;
hSRS = OSRNewSpatialReference( NULL );
/* -------------------------------------------------------------------- */
/* Look for an EPSG-like projection argument */
/* -------------------------------------------------------------------- */
if( projection->numargs == 1 &&
(pszInitEpsg = strcasestr(projection->args[0],"init=epsg:"))) {
int nEpsgCode = atoi(pszInitEpsg + strlen("init=epsg:"));
eErr = OSRImportFromEPSG(hSRS, nEpsgCode);
} else {
/* -------------------------------------------------------------------- */
/* Form arguments into a full Proj.4 definition string. */
/* -------------------------------------------------------------------- */
for( i = 0; i < projection->numargs; i++ )
nLength += strlen(projection->args[i]) + 2;
pszProj4 = (char *) CPLMalloc(nLength+2);
pszProj4[0] = '\0';
for( i = 0; i < projection->numargs; i++ ) {
strcat( pszProj4, "+" );
strcat( pszProj4, projection->args[i] );
strcat( pszProj4, " " );
}
/* -------------------------------------------------------------------- */
/* Ingest the string into OGRSpatialReference. */
/* -------------------------------------------------------------------- */
eErr = OSRImportFromProj4( hSRS, pszProj4 );
CPLFree( pszProj4 );
}
/* -------------------------------------------------------------------- */
/* Export as a WKT string. */
/* -------------------------------------------------------------------- */
if( eErr == OGRERR_NONE )
eErr = OSRExportToWkt( hSRS, &pszWKT );
OSRDestroySpatialReference( hSRS );
if( pszWKT ) {
char *pszWKT2 = msStrdup(pszWKT);
CPLFree( pszWKT );
return pszWKT2;
} else
return NULL;
#endif /* defined USE_GDAL or USE_OGR */
}