MITAB: add MITAB_BOUNDS_FILE to specify a file with projection bounds (…

…mapgears/mitab#3)

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@27564 f0d54148-0727-0410-94bb-9a71ac55c965

ogr/ogrsf_frmts/mitab/drv_mitab.html

@@ -59,10 +59,26 @@ <h2>Creation Issues</h2>
   <li>For any other projection: BOUNDS (-30000000, -15000000) (30000000, 15000000)</li>
 </ul>
 
+<p>
+Starting with GDAL 2.0, it is possible to specify a user-defined file that contain
+projection definitions with bounds.
+The name of this file must be specified with the MITAB_BOUNDS_FILE configuration
+option.
+This allows users to override the
+default bounds for existing projections, and to define bounds for new projections
+not listed in the hard-coded table in the driver.
+The format of the file is a simple text file with one CoordSys string
+per line.  The CoordSys lines should follow the MIF specs, and MUST 
+include the optional Bounds definition at the end of the line, e.g.
+<pre>
+# Lambert 93 French bounds
+CoordSys Earth Projection 3, 33, "m", 3, 46.5, 44, 49, 700000, 6600000 Bounds (75000, 6000000) (1275000, 7200000)
+</pre>
+</p>
 
 <p>
 If no coordinate system is provided when creating a layer, the projection
-case is used, not geographic which can result in very low precision if
+case is used, not geographic, which can result in very low precision if
 the coordinates really are geographic.  You can add "-a_srs WGS84" to the
 <b>ogr2ogr</b> commandline during a translation to force geographic mode.
 </p>

ogr/ogrsf_frmts/mitab/mitab_bounds.cpp

@@ -1040,6 +1040,7 @@ static const MapInfoBoundsInfo gasBoundsList[] = {
 
 #define TAB_EQUAL(a, b) (((a)<(b) ? ((b)-(a)) : ((a)-(b))) < 1e-6)
 
+static char szPreviousMitabBoundsFile[2048] = { 0 };
 
 /**********************************************************************
  *                     MITABLookupCoordSysBounds()
@@ -1056,6 +1057,25 @@ GBool MITABLookupCoordSysBounds(TABProjInfo *psCS,
     const MapInfoBoundsInfo *psList;
     MapInfoBoundsInfo **ppsList;
 
+    /*-----------------------------------------------------------------
+    * Try to load the user defined table if not loaded yet .
+    *----------------------------------------------------------------*/
+    const char * pszMitabBoundsFile = CPLGetConfigOption("MITAB_BOUNDS_FILE", NULL);
+    if (pszMitabBoundsFile != NULL && pszMitabBoundsFile[0] != '\0' )
+    {
+        if( strcmp(pszMitabBoundsFile, szPreviousMitabBoundsFile) != 0)
+        {
+            CPLStrlcpy(szPreviousMitabBoundsFile, pszMitabBoundsFile,
+                       sizeof(szPreviousMitabBoundsFile));
+            MITABLoadCoordSysTable(pszMitabBoundsFile);
+        }
+    }
+    else if ( szPreviousMitabBoundsFile[0] != '\0' )
+    {
+        MITABFreeCoordSysTable();
+        strcpy(szPreviousMitabBoundsFile, "");
+    }
+
     /*-----------------------------------------------------------------
      * Lookup table... 
      * Lookup external file if one was loaded, then lookup internal table.

ogr/ogrsf_frmts/mitab/mitab_coordsys.cpp

@@ -1595,6 +1595,8 @@ int MITABCoordSys2TABProjInfo(const char * pszCoordSys, TABProjInfo *psProj)
         psProj->adProjParams[iParam] = atof(papszNextField[0]);
         papszNextField++;         
     }
+
+    CSLDestroy(papszFields);
 
     return 0;
 }

ogr/ogrsf_frmts/mitab/mitab_ogr_driver.cpp

@@ -200,6 +200,15 @@ static CPLErr OGRTABDriverDelete( const char *pszDataSource )
     return CE_None;
 }
 
+/************************************************************************/
+/*                          OGRTABDriverUnload()                        */
+/************************************************************************/
+
+static void OGRTABDriverUnload(GDALDriver* poDriver)
+{
+    MITABFreeCoordSysTable();
+}
+
 /************************************************************************/
 /*              RegisterOGRTAB()                                        */
 /************************************************************************/
@@ -230,6 +239,7 @@ void RegisterOGRTAB()
         poDriver->pfnIdentify = OGRTABDriverIdentify;
         poDriver->pfnCreate = OGRTABDriverCreate;
         poDriver->pfnDelete = OGRTABDriverDelete;
+        poDriver->pfnUnloadDriver = OGRTABDriverUnload;
 
         GetGDALDriverManager()->RegisterDriver( poDriver );
     }