Commit 69535b7b authored by Justin Bronn's avatar Justin Bronn
Browse files

The `OGRGeometry.coord_dim` property may now be set; implemented a work-around... 

The `OGRGeometry.coord_dim` property may now be set; implemented a work-around for an OGR bug that changed geometries to 3D after transformation.  Refs #11433.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@11628 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent e5ab340d

django/contrib/gis/gdal/geometries.py

+37 −16
Original line number Diff line number Diff line
@@ -179,10 +179,17 @@ class OGRGeometry(GDALBase): 
        "Returns 0 for points, 1 for lines, and 2 for surfaces."

        return capi.get_dims(self.ptr)



    @property

    def coord_dim(self):

    def _get_coord_dim(self):

        "Returns the coordinate dimension of the Geometry."

        return capi.get_coord_dims(self.ptr)

        return capi.get_coord_dim(self.ptr)



    def _set_coord_dim(self, dim):

        "Sets the coordinate dimension of this Geometry."

        if not dim in (2, 3):

            raise ValueError('Geometry dimension must be either 2 or 3')

        capi.set_coord_dim(self.ptr, dim)



    coord_dim = property(_get_coord_dim, _set_coord_dim)



    @property

    def geom_count(self):
@@ -363,6 +370,16 @@ class OGRGeometry(GDALBase): 
            klone = self.clone()

            klone.transform(coord_trans)

            return klone



        # Have to get the coordinate dimension of the original geometry

        # so it can be used to reset the transformed geometry's dimension

        # 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

        orig_dim = self.coord_dim



        # Depending on the input type, use the appropriate OGR routine

        # to perform the transformation.

        if isinstance(coord_trans, CoordTransform):

            capi.geom_transform(self.ptr, coord_trans.ptr)

        elif isinstance(coord_trans, SpatialReference):
@@ -373,6 +390,10 @@ class OGRGeometry(GDALBase): 
        else:

            raise TypeError('Transform only accepts CoordTransform, SpatialReference, string, and integer objects.')



        # Setting with original dimension, see comment above.

        if self.coord_dim != orig_dim:

            self.coord_dim = orig_dim



    def transform_to(self, srs):

        "For backwards-compatibility."

        self.transform(srs)

django/contrib/gis/gdal/prototypes/geom.py

+2 −1
Original line number Diff line number Diff line
@@ -83,7 +83,8 @@ get_geom_srs = srs_output(lgdal.OGR_G_GetSpatialReference, [c_void_p]) 
get_area = double_output(lgdal.OGR_G_GetArea, [c_void_p])

get_centroid = void_output(lgdal.OGR_G_Centroid, [c_void_p, c_void_p])

get_dims = int_output(lgdal.OGR_G_GetDimension, [c_void_p])

get_coord_dims = int_output(lgdal.OGR_G_GetCoordinateDimension, [c_void_p])

get_coord_dim = int_output(lgdal.OGR_G_GetCoordinateDimension, [c_void_p])

set_coord_dim = void_output(lgdal.OGR_G_SetCoordinateDimension, [c_void_p, c_int], errcheck=False)



get_geom_count = int_output(lgdal.OGR_G_GetGeometryCount, [c_void_p])

get_geom_name = const_string_output(lgdal.OGR_G_GetGeometryName, [c_void_p])

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

+12 −0
Original line number Diff line number Diff line
@@ -319,6 +319,18 @@ class OGRGeomTest(unittest.TestCase): 
            self.assertAlmostEqual(trans.x, p.x, prec)

            self.assertAlmostEqual(trans.y, p.y, prec)



    def test09c_transform_dim(self):

        "Testing coordinate dimension is the same on transformed geometries."

        ls_orig = OGRGeometry('LINESTRING(-104.609 38.255)', 4326)

        ls_trans = OGRGeometry('LINESTRING(992385.4472045 481455.4944650)', 2774)

        

        prec = 3

        ls_orig.transform(ls_trans.srs)

        # Making sure the coordinate dimension is still 2D.

        self.assertEqual(2, ls_orig.coord_dim)

        self.assertAlmostEqual(ls_trans.x[0], ls_orig.x[0], prec)

        self.assertAlmostEqual(ls_trans.y[0], ls_orig.y[0], prec)



    def test10_difference(self):

        "Testing difference()."

        for i in xrange(len(topology_geoms)):