[1.1.X] Fixed #12312 -- Set the coordinate dimension on each component of geometry collections after transform (refines GDAL bug workaround introduced in r11629). Thanks, yourcelf for bug report.

Backport of r12878 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12879 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/gdal/geometries.py

@@ -48,11 +48,11 @@ from django.contrib.gis.gdal.base import GDALBase
 from django.contrib.gis.gdal.envelope import Envelope, OGREnvelope
 from django.contrib.gis.gdal.error import OGRException, OGRIndexError, SRSException
 from django.contrib.gis.gdal.geomtype import OGRGeomType
+from django.contrib.gis.gdal.libgdal import GEOJSON, GDAL_VERSION
 from django.contrib.gis.gdal.srs import SpatialReference, CoordTransform
 
 # Getting the ctypes prototype functions that interface w/the GDAL C library.
 from django.contrib.gis.gdal.prototypes import geom as capi, srs as srs_api
-GEOJSON = capi.GEOJSON
 
 # For more information, see the OGR C API source code:
 #  http://www.gdal.org/ogr/ogr__api_8h.html
@@ -374,6 +374,7 @@ class OGRGeometry(GDALBase):
         # afterwards.  This is done because of GDAL bug (in versions prior
         # to 1.7) that turns geometries 3D after transformation, see:
         #  http://trac.osgeo.org/gdal/changeset/17792
+        if GDAL_VERSION < (1, 7):
             orig_dim = self.coord_dim
 
         # Depending on the input type, use the appropriate OGR routine
@@ -386,9 +387,20 @@ class OGRGeometry(GDALBase):
             sr = SpatialReference(coord_trans)
             capi.geom_transform_to(self.ptr, sr.ptr)
         else:
-            raise TypeError('Transform only accepts CoordTransform, SpatialReference, string, and integer objects.')
+            raise TypeError('Transform only accepts CoordTransform, '
+                            'SpatialReference, string, and integer objects.')
 
         # Setting with original dimension, see comment above.
+        if GDAL_VERSION < (1, 7):
+            if isinstance(self, GeometryCollection):
+                # With geometry collections have to set dimension on
+                # each internal geometry reference, as the collection
+                # dimension isn't affected.
+                for i in xrange(len(self)):
+                    internal_ptr = capi.get_geom_ref(self.ptr, i)
+                    if orig_dim != capi.get_coord_dim(internal_ptr):
+                        capi.set_coord_dim(internal_ptr, orig_dim)
+            else:
                 if self.coord_dim != orig_dim:
                     self.coord_dim = orig_dim
 

django/contrib/gis/gdal/tests/test_geom.py

@@ -436,6 +436,31 @@ class OGRGeomTest(unittest.TestCase):
         self.assertEqual([1.0, 2.0, 3.0], ls_25d.z)
         self.assertEqual(3, ls_25d.coord_dim)
 
+    def test18_ogrgeometry_transform_workaround(self):
+        "Testing coordinate dimensions on geometries after transformation."
+        # A bug in GDAL versions prior to 1.7 changes the coordinate
+        # dimension of a geometry after it has been transformed.
+        # This test ensures that the bug workarounds employed within
+        # `OGRGeometry.transform` indeed work.
+        wkt_2d = "MULTILINESTRING ((0 0,1 1,2 2))"
+        wkt_3d = "MULTILINESTRING ((0 0 0,1 1 1,2 2 2))"
+        srid = 4326
+
+        # For both the 2D and 3D MultiLineString, ensure _both_ the dimension
+        # of the collection and the component LineString have the expected
+        # coordinate dimension after transform.
+        geom = OGRGeometry(wkt_2d, srid)
+        geom.transform(srid)
+        self.assertEqual(2, geom.coord_dim)
+        self.assertEqual(2, geom[0].coord_dim)
+        self.assertEqual(wkt_2d, geom.wkt)
+
+        geom = OGRGeometry(wkt_3d, srid)
+        geom.transform(srid)
+        self.assertEqual(3, geom.coord_dim)
+        self.assertEqual(3, geom[0].coord_dim)
+        self.assertEqual(wkt_3d, geom.wkt)
+
 def suite():
     s = unittest.TestSuite()
     s.addTest(unittest.makeSuite(OGRGeomTest))