def test_polygonizeMask():
# test a simple box
boxmask = np.array([[0, 0, 0, 0, 0], [0, 1, 1, 1, 0], [0, 1, 0, 1, 0],
[0, 1, 1, 1, 0], [0, 0, 0, 0, 0]],
dtype=np.bool)
g1 = geom.polygonizeMask(boxmask, shrink=None)
assert np.isclose(g1.Area(), 8.0) # polygonizeMask: simple area
assert g1.GetSpatialReference() is None # polygonizeMask: empty srs
# test shrink
g1b = geom.polygonizeMask(boxmask, shrink=0.0001)
assert np.isclose(g1b.Area(), 7.99984000) # polygonizeMask: shrunk area
# test a more complex area
complexmask = np.array([[0, 1, 0, 0, 0], [1, 1, 0, 1, 0], [0, 0, 0, 1, 1],
[1, 1, 0, 1, 0], [0, 1, 0, 0, 0]],
dtype=np.bool)
g2 = geom.polygonizeMask(complexmask, shrink=None, flat=False)
assert np.isclose(len(g2), 3) # polygonizeMask: geometry count
assert np.isclose(sum([g.Area() for g in g2]),
10.0) # polygonizeMask: area
# flatten the complex area
g3 = geom.polygonizeMask(complexmask, flat=True, shrink=None)
assert np.isclose(g3.Area(), 10.0) # polygonizeMask: flattened area
# set a boundary and srs context
g4 = geom.polygonizeMask(complexmask,
bounds=(-3, 10, 22, 35),
srs=EPSG3035,
flat=True,
shrink=None)
assert np.isclose(g4.Area(), 250.0) # polygonizeMask: contexted area
assert g4.GetSpatialReference().IsSame(
EPSG3035) # error("polygonizeMask: contexted srs
def test_transform():
# test a single point
pt = geom.point(7, 48, srs=EPSG4326)
t1 = geom.transform(pt, toSRS=EPSG3035)
assert np.isclose(t1.GetX(), 4097075.016)
assert np.isclose(t1.GetY(), 2769703.15423898)
# make a collection of polygons using polygonizeMask
complexmask = np.array([[0, 1, 0, 0, 0], [1, 1, 0, 1, 0], [0, 0, 0, 1, 1],
[1, 1, 0, 1, 0], [0, 1, 0, 0, 0]],
dtype=np.bool)
polygons = geom.polygonizeMask(complexmask,
bounds=(6, 45, 11, 50),
flat=False,
srs=EPSG4326,
shrink=None)
t2 = geom.transform(polygons, toSRS='europe_m', segment=0.1)
assert (len(t2) == 3) # "Transform Count
assert t2[0].GetSpatialReference().IsSame(EPSG3035) # "Transform srs
assert np.isclose(sum([t.Area() for t in t2]),
83747886418.48529) # "Transform Area