GeoPackage: Fix handling of invalid SRS ID (#3286)

GeoPackage 1.2.1 1.1.1.1.1. File Format Requirement 11 The record with an srs_id of -1 SHALL be used for undefined Cartesian coordinate reference systems. The record with an srs_id of 0 SHALL be used for undefined geographic coordinate reference systems.
OSGeo · Dec 15, 2020 · 3c2a318 · 3c2a318
1 parent 7766e11
commit 3c2a318
Show file tree

Hide file tree

Showing 3 changed files with 42 additions and 14 deletions.
diff --git a/autotest/gdrivers/gpkg.py b/autotest/gdrivers/gpkg.py
@@ -1206,7 +1206,8 @@ def test_gpkg_15():
 
     # Repeated SetProjection()
     out_ds = gdal.Open('/vsimem/tmp.gpkg', gdal.GA_Update)
-    assert out_ds.GetProjectionRef() == ''
+    assert out_ds.GetSpatialRef().IsLocal()
+    assert out_ds.GetProjectionRef().find('Undefined cartesian SRS') >= 0
     srs = osr.SpatialReference()
     srs.ImportFromEPSG(4326)
     ret = out_ds.SetProjection(srs.ExportToWkt())
@@ -1220,7 +1221,8 @@ def test_gpkg_15():
     out_ds = None
 
     out_ds = gdal.Open('/vsimem/tmp.gpkg')
-    assert out_ds.GetProjectionRef() == ''
+    assert out_ds.GetSpatialRef().IsLocal()
+    assert out_ds.GetProjectionRef().find('Undefined cartesian SRS') >= 0
     # Test setting on read-only dataset
     gdal.PushErrorHandler()
     ret = out_ds.SetProjection('')

diff --git a/autotest/ogr/ogr_gpkg.py b/autotest/ogr/ogr_gpkg.py
@@ -898,20 +898,28 @@ def test_ogr_gpkg_15():
         pytest.fail()
     gpkg_ds.ReleaseResultSet(sql_lyr)
 
-    # Invalid target SRID
+    # Invalid target SRID=0
+    # GeoPackage: The record with an srs_id of 0 SHALL be used for undefined geographic coordinate reference systems.
     with gdaltest.error_handler():
-        sql_lyr = gpkg_ds.ExecuteSQL("SELECT ST_Transform(geom, 0) FROM tbl_linestring_renamed")
+        sql_lyr = gpkg_ds.ExecuteSQL("SELECT ST_Transform(geom, 0), ST_SRID(ST_Transform(geom, 0)) FROM tbl_linestring_renamed")
+    assert sql_lyr.GetSpatialRef().ExportToWkt().find('Undefined geographic SRS') >= 0
     feat = sql_lyr.GetNextFeature()
-    if feat.GetGeometryRef() is not None:
+    if feat.GetGeometryRef() is None or feat.GetField(0) != 0:
         feat.DumpReadable()
         pytest.fail()
     gpkg_ds.ReleaseResultSet(sql_lyr)
 
-    # Invalid source SRID
+    # Invalid source SRID=0
+    # GeoPackage: The record with an srs_id of 0 SHALL be used for undefined geographic coordinate reference systems.
+    # The source is undefined geographic coordinate reference systems (based on WGS84) and the target is WGS84,
+    # and the result is an identity transformation that leaves geometry unchanged.
+    src_lyr = gpkg_ds.GetLayerByName("point-with-spi-and-dashes")
+    assert src_lyr.GetSpatialRef().ExportToWkt().find('Undefined geographic SRS') >= 0
     with gdaltest.error_handler():
-        sql_lyr = gpkg_ds.ExecuteSQL("SELECT ST_Transform(geom, 4326) FROM \"point-with-spi-and-dashes\"")
+        sql_lyr = gpkg_ds.ExecuteSQL("SELECT ST_Transform(geom, 4326), ST_SRID(ST_Transform(geom, 4326)) FROM \"point-with-spi-and-dashes\"")
+    assert sql_lyr.GetSpatialRef().ExportToWkt().find('WGS_1984') >= 0
     feat = sql_lyr.GetNextFeature()
-    if feat.GetGeometryRef() is not None:
+    if feat.GetGeometryRef() is None or feat.GetField(0) != 4326:
         feat.DumpReadable()
         pytest.fail()
     gpkg_ds.ReleaseResultSet(sql_lyr)

diff --git a/gdal/ogr/ogrsf_frmts/gpkg/ogrgeopackagedatasource.cpp b/gdal/ogr/ogrsf_frmts/gpkg/ogrgeopackagedatasource.cpp
@@ -336,12 +336,6 @@ static OGRErr GDALGPKGImportFromEPSG(OGRSpatialReference *poSpatialRef,
 OGRSpatialReference* GDALGeoPackageDataset::GetSpatialRef(int iSrsId,
                                                           bool bFallbackToEPSG)
 {
-    /* Should we do something special with undefined SRS ? */
-    if( iSrsId == 0 || iSrsId == -1 )
-    {
-        return nullptr;
-    }
-
     std::map<int, OGRSpatialReference*>::const_iterator oIter =
                                                 m_oMapSrsIdToSrs.find(iSrsId);
     if( oIter != m_oMapSrsIdToSrs.end() )
@@ -352,6 +346,30 @@ OGRSpatialReference* GDALGeoPackageDataset::GetSpatialRef(int iSrsId,
         return oIter->second;
     }
 
+    if( iSrsId == 0 || iSrsId == -1 )
+    {
+        OGRSpatialReference *poSpatialRef = new OGRSpatialReference();
+        poSpatialRef->SetAxisMappingStrategy( OAMS_TRADITIONAL_GIS_ORDER );
+
+        if( iSrsId == 0)
+        {
+            poSpatialRef->SetGeogCS("Undefined geographic SRS",
+                                    "unknown",
+                                    "unknown",
+                                    SRS_WGS84_SEMIMAJOR,
+                                    SRS_WGS84_INVFLATTENING);
+        }
+        else if( iSrsId == -1)
+        {
+            poSpatialRef->SetLocalCS("Undefined cartesian SRS");
+            poSpatialRef->SetLinearUnits( SRS_UL_METER, 1.0 );
+        }
+
+        m_oMapSrsIdToSrs[iSrsId] = poSpatialRef;
+        poSpatialRef->Reference();
+        return poSpatialRef;
+    }
+
     CPLString oSQL;
     oSQL.Printf( "SELECT definition, organization, organization_coordsys_id%s "
                  "FROM gpkg_spatial_ref_sys WHERE definition IS NOT NULL AND "