def test_clip_points_by_polygons_with_holes0(self):
"""Points can be clipped by polygons with holes
"""
# Define an outer ring
outer_ring = numpy.array([[106.79, -6.233], [106.80, -6.24],
[106.78, -6.23], [106.77, -6.21],
[106.79, -6.233]])
# Define inner rings
inner_rings = [
numpy.array([[106.77827, -6.2252], [106.77775, -6.22378],
[106.78, -6.22311], [106.78017, -6.22530],
[106.77827, -6.2252]])[::-1],
numpy.array([[106.78652, -6.23215], [106.78642, -6.23075],
[106.78746, -6.23143], [106.78831, -6.23307],
[106.78652, -6.23215]])[::-1]
]
v = Vector(
geometry=[Polygon(outer_ring=outer_ring, inner_rings=inner_rings)])
assert v.is_polygon_data
# Write it to file
tmp_filename = unique_filename(suffix='.shp')
v.write_to_file(tmp_filename)
# Read polygon it back
L = read_layer(tmp_filename)
P = L.get_geometry(as_geometry_objects=True)[0]
outer_ring = P.outer_ring
inner_ring0 = P.inner_rings[0]
inner_ring1 = P.inner_rings[1]
# Make some test points
points = generate_random_points_in_bbox(outer_ring, 1000, seed=13)
# Clip to outer ring, excluding holes
indices = inside_polygon(points, P.outer_ring, holes=P.inner_rings)
# Sanity
for point in points[indices, :]:
# Must be inside outer ring
assert is_inside_polygon(point, outer_ring)
# But not in any of the inner rings
assert not is_inside_polygon(point, inner_ring0)
assert not is_inside_polygon(point, inner_ring1)
if False:
# Store for visual check
pol = Vector(geometry=[P])
tmp_filename = unique_filename(suffix='.shp')
pol.write_to_file(tmp_filename)
# print 'Polygon with holes written to %s' % tmp_filename
pts = Vector(geometry=points[indices, :])
tmp_filename = unique_filename(suffix='.shp')
pts.write_to_file(tmp_filename)
def make_circular_polygon(centers, radii, attributes=None):
"""Create circular polygon in geographic coordinates
Args:
centers: list of (longitude, latitude)
radii: desired approximate radii in meters (must be
monotonically ascending).
Can be either one number or list of numbers
attributes (optional): Attributes for each center
Returns:
Vector polygon layer representing circle in WGS84
"""
if not isinstance(radii, list):
radii = [radii]
# FIXME (Ole): Check that radii are monotonically increasing
circles = []
new_attributes = []
for i, center in enumerate(centers):
p = Point(longitude=center[0], latitude=center[1])
inner_rings = None
for radius in radii:
# Generate circle polygon
C = p.generate_circle(radius)
circles.append(Polygon(outer_ring=C, inner_rings=inner_rings))
# Store current circle and inner ring for next poly
inner_rings = [C]
# Carry attributes for center forward
attr = {}
if attributes is not None:
for key in attributes[i]:
attr[key] = attributes[i][key]
# Add radius to this ring
attr['Radius'] = radius
new_attributes.append(attr)
Z = Vector(
geometry=circles, # List with circular polygons
data=new_attributes, # Associated attributes
geometry_type='polygon')
return Z
def buffer_points(centers, radii, hazard_zone_attribute, data_table=None):
"""Buffer points for each center with defined radii.
If the data_table is defined, then the data will also be copied to the
result. This function is used for making buffer of volcano point hazard.
:param centers: All center of each point (longitude, latitude)
:type centers: list
:param radii: Desired approximate radii in meters (must be
monotonically ascending). Can be either one number or list of numbers
:type radii: int, list
:param hazard_zone_attribute: The name of the attributes representing
hazard zone.
:type hazard_zone_attribute: str
:param data_table: Data for each center (optional)
:type data_table: list
:return: Vector polygon layer representing circle in WGS84
:rtype: Vector
"""
if not isinstance(radii, list):
radii = [radii]
# Check that radii are monotonically increasing
monotonically_increasing_flag = all(
x < y for x, y in zip(radii, radii[1:]))
if not monotonically_increasing_flag:
raise RadiiException(RadiiException.suggestion)
circles = []
new_data_table = []
for i, center in enumerate(centers):
p = Point(longitude=center[0], latitude=center[1])
inner_rings = None
for radius in radii:
# Generate circle polygon
circle = p.generate_circle(radius)
circles.append(Polygon(outer_ring=circle, inner_rings=inner_rings))
# Store current circle and inner ring for next poly
inner_rings = [circle]
# Carry attributes for center forward (deep copy)
row = {}
if data_table is not None:
for key in data_table[i]:
row[key] = data_table[i][key]
# Add radius to this ring
row[hazard_zone_attribute] = radius
new_data_table.append(row)
circular_polygon = Vector(
geometry=circles, # List with circular polygons
data=new_data_table, # Associated attributes
geometry_type='polygon')
return circular_polygon