overriding worldfile with GDAL

[mko]

In 5.2.0 there's a new processing instruction in 5.2.0 'EXTENT_PRIORITY=WORLDFILE'. In rare cases (read only volumes with tiffs without tfw) one may even have to specify another path where the tfw resides.

A workaround uses a new processing instruction 'WORLDFILE' which can be set in the mapfile 'PROCESSING "WORLDFILE=/tmp/file.tfw"'. msGetGDALGeoTransform():

/* -------------------------------------------------------------------- */
/*      Do we want to override GDAL with a worldfile if one is present? */
/* -------------------------------------------------------------------- */

... EXTENT_PRIORITY ...

    worldfile = CSLFetchNameValue( layer->processing,
                                   "WORLDFILE" );

    if( worldfile != NULL
        && msBuildPath(szPath, map->mappath, worldfile) != NULL
        && strrchr(szPath,'.') != NULL )
    {
         char *extension = strdup(strrchr(szPath,'.')+1);
         strrchr(szPath,'.')[0] = '\0';

         if( GDALReadWorldFile(szPath, extension,
                                 padfGeoTransform) )
         {
            msDebug("msGetGDALGeoTransform(): Using alternative worldfile %s.%s\n", szPath, extension);
            return MS_SUCCESS;
         }
    }

One may combine it with EXTENT_PRIORITY.

[mko]

supports multiple world files