ogr_geos.py

#!/usr/bin/env pytest
# -*- coding: utf-8 -*-
###############################################################################
# $Id$
#
# Project:  GDAL/OGR Test Suite
# Purpose:  Test GEOS integration in OGR - geometric operations.
# Author:   Frank Warmerdam <warmerdam@pobox.com>
#
###############################################################################
# Copyright (c) 2004, Frank Warmerdam <warmerdam@pobox.com>
# Copyright (c) 2009-2012, Even Rouault <even dot rouault at spatialys.com>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Library General Public License for more details.
#
# You should have received a copy of the GNU Library General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
###############################################################################


import gdaltest
import ogrtest
import pytest

from osgeo import gdal, ogr

pytestmark = pytest.mark.require_geos

###############################################################################
# Establish whether we have GEOS support integrated, testing simple Union.


def test_ogr_geos_union():

    pnt1 = ogr.CreateGeometryFromWkt("POINT(10 20)")
    pnt2 = ogr.CreateGeometryFromWkt("POINT(30 20)")

    result = pnt1.Union(pnt2)

    ogrtest.check_feature_geometry(result, "MULTIPOINT (10 20,30 20)")


###############################################################################
# Test polygon intersection.


def test_ogr_geos_intersection():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 0 10, 10 0, 0 0))")

    result = g1.Intersection(g2)

    ogrtest.check_feature_geometry(result, "POLYGON ((0 0,5 5,10 0,0 0))")


###############################################################################
# Test polygon difference.


def test_ogr_geos_difference():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 0 10, 10 0, 0 0))")

    result = g1.Difference(g2)

    ogrtest.check_feature_geometry(result, "POLYGON ((5 5,10 10,10 0,5 5))")


###############################################################################
# Test polygon symmetric difference.


def test_ogr_geos_symmetric_difference():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 0 10, 10 0, 0 0))")

    result = g1.SymmetricDifference(g2)

    ogrtest.check_feature_geometry(
        result, "MULTIPOLYGON (((5 5,0 0,0 10,5 5)),((5 5,10 10,10 0,5 5)))"
    )


###############################################################################
# Test polygon symmetric difference.


def test_ogr_geos_sym_difference():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 0 10, 10 0, 0 0))")

    result = g1.SymDifference(g2)

    ogrtest.check_feature_geometry(
        result, "MULTIPOLYGON (((5 5,0 0,0 10,5 5)),((5 5,10 10,10 0,5 5)))"
    )


###############################################################################
# Test Intersect().


def test_ogr_geos_intersect():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("LINESTRING(10 0, 0 10)")

    result = g1.Intersect(g2)

    assert result != 0, "wrong result (got false)"

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((20 20, 20 30, 30 20, 20 20))")

    result = g1.Intersect(g2)

    assert result == 0, "wrong result (got true)"


###############################################################################
# Test disjoint().


def test_ogr_geos_disjoint():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("LINESTRING(10 0, 0 10)")

    result = g1.Disjoint(g2)

    assert result == 0, "wrong result (got true)"

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((20 20, 20 30, 30 20, 20 20))")

    result = g1.Disjoint(g2)

    assert result != 0, "wrong result (got false)"


###############################################################################
# Test touches.


def test_ogr_geos_touches():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 0 10)")

    result = g1.Touches(g2)

    assert result != 0, "wrong result (got false)"

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((20 20, 20 30, 30 20, 20 20))")

    result = g1.Touches(g2)

    assert result == 0, "wrong result (got true)"


###############################################################################
# Test crosses.


def test_ogr_geos_crosses():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("LINESTRING(10 0, 0 10)")

    result = g1.Crosses(g2)

    assert result != 0, "wrong result (got false)"

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 10 10)")
    g2 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 0 10)")

    result = g1.Crosses(g2)

    assert result == 0, "wrong result (got true)"


###############################################################################


def test_ogr_geos_within():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((-90 -90, -90 90, 190 -90, -90 -90))")

    result = g1.Within(g2)

    assert result != 0, "wrong result (got false)"

    result = g2.Within(g1)

    assert result == 0, "wrong result (got true)"


###############################################################################


def test_ogr_geos_contains():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((-90 -90, -90 90, 190 -90, -90 -90))")

    result = g2.Contains(g1)

    assert result != 0, "wrong result (got false)"

    result = g1.Contains(g2)

    assert result == 0, "wrong result (got true)"


###############################################################################


def test_ogr_geos_overlaps():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((-90 -90, -90 90, 190 -90, -90 -90))")

    result = g2.Overlaps(g1)

    # g1 and g2 intersect, but their intersection is equal to g1
    assert result == 0, "wrong result (got true)"

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")
    g2 = ogr.CreateGeometryFromWkt("POLYGON((0 -5,10 5,10 -5,0 -5))")

    result = g2.Overlaps(g1)

    assert result != 0, "wrong result (got false)"


###############################################################################


def test_ogr_geos_buffer():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")

    result = g1.Buffer(1.0, 3)
    assert result is not None
    assert result.Area() > g1.Area()


###############################################################################


def test_ogr_geos_centroid():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")

    centroid = g1.Centroid()

    ogrtest.check_feature_geometry(centroid, "POINT(6.666666667 3.333333333)")

    # Test with a self intersecting polygon too.
    # This particular polygon has two triangles. The right triangle is larger.
    g2 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 0 2, 2 -0.1, 2 2.1, 0 0))")
    centroid2 = g2.Centroid()

    ogrtest.check_feature_geometry(centroid2, "POINT (8.0 1.0)")


###############################################################################


def test_ogr_geos_centroid_multipolygon():

    g1 = ogr.CreateGeometryFromWkt(
        "MULTIPOLYGON(((0 0,0 1,1 1,1 0,0 0)),((2 0,2 1,3 1,3 0,2 0)))"
    )

    centroid = g1.Centroid()

    ogrtest.check_feature_geometry(centroid, "POINT (1.5 0.5)")


###############################################################################


def test_ogr_geos_centroid_point_empty():

    g1 = ogr.CreateGeometryFromWkt("POINT EMPTY")

    centroid = g1.Centroid()

    assert centroid.ExportToWkt() == "POINT EMPTY", "Got: %s" % centroid.ExportToWkt()


###############################################################################


def test_ogr_geos_simplify_linestring():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0,1 0,10 0)")

    gdal.ErrorReset()
    simplify = g1.Simplify(5)

    assert simplify.ExportToWkt() == "LINESTRING (0 0,10 0)", (
        "Got: %s" % simplify.ExportToWkt()
    )


###############################################################################


def test_ogr_geos_simplifypreservetopology_linestring():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0,1 0,10 0)")

    gdal.ErrorReset()
    simplify = g1.SimplifyPreserveTopology(5)

    assert simplify.ExportToWkt() == "LINESTRING (0 0,10 0)", (
        "Got: %s" % simplify.ExportToWkt()
    )


###############################################################################


def test_ogr_geos_unioncascaded():

    g1 = ogr.CreateGeometryFromWkt(
        "MULTIPOLYGON(((0 0,0 1,1 1,1 0,0 0)),((0.5 0.5,0.5 1.5,1.5 1.5,1.5 0.5,0.5 0.5)))"
    )

    gdal.ErrorReset()
    cascadedunion = g1.UnionCascaded()

    ogrtest.check_feature_geometry(
        cascadedunion,
        "POLYGON ((0 0,0 1,0.5 1.0,0.5 1.5,1.5 1.5,1.5 0.5,1.0 0.5,1 0,0 0))",
    )


###############################################################################


def test_ogr_geos_unioncascaded_empty_multipolygon():

    g1 = ogr.Geometry(ogr.wkbMultiPolygon)
    cascadedunion = g1.UnionCascaded()
    assert cascadedunion.IsEmpty()


###############################################################################


def test_ogr_geos_convexhull():

    g1 = ogr.CreateGeometryFromWkt(
        "GEOMETRYCOLLECTION(POINT(0 1), POINT(0 0), POINT(1 0), POINT(1 1))"
    )

    convexhull = g1.ConvexHull()

    assert convexhull.ExportToWkt() == "POLYGON ((0 0,0 1,1 1,1 0,0 0))", (
        "Got: %s" % convexhull.ExportToWkt()
    )


###############################################################################


@gdaltest.disable_exceptions()
def test_ogr_geos_concavehull():

    g1 = ogr.CreateGeometryFromWkt("MULTIPOINT(0 0,0.4 0.5,0 1,1 1,0.6 0.5,1 0)")

    with gdal.quiet_errors():
        res = g1.ConcaveHull(0.5, False)

    if res is None:
        assert "GEOS 3.11" in gdal.GetLastErrorMsg()
        pytest.skip(gdal.GetLastErrorMsg())

    with gdal.quiet_errors():
        res = g1.ConcaveHull(-1, False)
    assert res is None


###############################################################################


def test_ogr_geos_distance():

    g1 = ogr.CreateGeometryFromWkt("POINT(0 0)")
    g2 = ogr.CreateGeometryFromWkt("POINT(1 0)")

    distance = g1.Distance(g2)

    assert distance == pytest.approx(1, abs=0.00000000001), (
        "Distance() result wrong, got %g." % distance
    )


###############################################################################


def test_ogr_geos_isring():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0,0 1,1 1,0 0)")

    isring = g1.IsRing()

    assert isring == 1


###############################################################################


def test_ogr_geos_issimple_true():

    g1 = ogr.CreateGeometryFromWkt("POLYGON ((0 0,0 1,1 1,1 0,0 0))")

    isring = g1.IsSimple()

    assert isring == 1


###############################################################################


def test_ogr_geos_issimple_false():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(1 1,2 2,2 3.5,1 3,1 2,2 1)")

    isring = g1.IsSimple()

    assert isring == 0


###############################################################################


def test_ogr_geos_isvalid_true():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING(0 0, 1 1)")

    isring = g1.IsValid()

    assert isring == 1


###############################################################################


def test_ogr_geos_isvalid_true_linestringM():

    g1 = ogr.CreateGeometryFromWkt("LINESTRING M(0 0 10, 1 1 20)")

    isring = g1.IsValid()

    assert isring == 1


###############################################################################


def test_ogr_geos_isvalid_true_circularStringM():

    g1 = ogr.CreateGeometryFromWkt("CIRCULARSTRING M(0 0 10, 1 1 20,2 0 30)")

    isring = g1.IsValid()

    assert isring == 1


###############################################################################


def test_ogr_geos_isvalid_true_triangle():

    g1 = ogr.CreateGeometryFromWkt("TRIANGLE ((0 0,0 1,1 1,0 0))")

    isring = g1.IsValid()

    assert isring == 1


###############################################################################


def test_ogr_geos_isvalid_false():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0,1 1,1 2,1 1,0 0))")

    with gdal.quiet_errors():
        isring = g1.IsValid()

    assert isring == 0


###############################################################################


def test_ogr_geos_isvalid_false_too_few_points():
    g1 = ogr.CreateGeometryFromWkt(
        "POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0), (2 2, 3 2, 2 2))"
    )

    with ogr.ExceptionMgr():  # fail test if exception is thrown
        with gdal.quiet_errors():
            isvalid = g1.IsValid()

    assert isvalid == 0


###############################################################################


def test_ogr_geos_pointonsurface():

    g1 = ogr.CreateGeometryFromWkt("POLYGON((0 0, 10 10, 10 0, 0 0))")

    pointonsurface = g1.PointOnSurface()

    assert pointonsurface.Within(g1) == 1


###############################################################################


def test_ogr_geos_DelaunayTriangulation():

    g1 = ogr.CreateGeometryFromWkt("MULTIPOINT(0 0,0 1,1 1,1 0)")

    gdal.ErrorReset()
    triangulation = g1.DelaunayTriangulation()
    if triangulation is None:
        assert gdal.GetLastErrorMsg() != ""
        pytest.skip()

    assert (
        triangulation.ExportToWkt()
        == "GEOMETRYCOLLECTION (POLYGON ((0 1,0 0,1 0,0 1)),POLYGON ((0 1,1 0,1 1,0 1)))"
    ), ("Got: %s" % triangulation.ExportToWkt())


###############################################################################


def test_ogr_geos_polygonize():

    g = ogr.CreateGeometryFromWkt("MULTILINESTRING((0 0,0 1,1 1),(1 1,0 0))")
    got = g.Polygonize()
    assert got.ExportToWkt() == "GEOMETRYCOLLECTION (POLYGON ((0 0,0 1,1 1,0 0)))", (
        "Got: %s" % got.ExportToWkt()
    )

    g = ogr.CreateGeometryFromWkt("POINT EMPTY")
    got = g.Polygonize()
    assert got is None, "Got: %s" % got.ExportToWkt()

    g = ogr.CreateGeometryFromWkt("GEOMETRYCOLLECTION(POINT EMPTY)")
    got = g.Polygonize()
    assert got is None, "Got: %s" % got.ExportToWkt()


###############################################################################


def test_ogr_geos_prepared_geom():

    g = ogr.CreateGeometryFromWkt("POLYGON((0 0,0 1,1 1,1 0,0 0))")
    pg = g.CreatePreparedGeometry()

    assert pg.Contains(ogr.CreateGeometryFromWkt("POINT(0.5 0.5)"))
    assert not pg.Contains(ogr.CreateGeometryFromWkt("POINT(-0.5 0.5)"))

    g2 = ogr.CreateGeometryFromWkt("POLYGON((0.5 0,0.5 1,1.5 1,1.5 0,0.5 0))")
    assert pg.Intersects(g2)
    assert not pg.Intersects(ogr.CreateGeometryFromWkt("POINT(-0.5 0.5)"))

    # Test workaround for https://github.com/libgeos/geos/pull/423
    assert not pg.Intersects(ogr.CreateGeometryFromWkt("POINT EMPTY"))
    assert not pg.Contains(ogr.CreateGeometryFromWkt("POINT EMPTY"))