116 lines
4.1 KiB
Python
116 lines
4.1 KiB
Python
"""
|
|
This module houses the Geometry Collection objects:
|
|
GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon
|
|
"""
|
|
from ctypes import byref, c_int, c_uint
|
|
|
|
from django.contrib.gis.geos import prototypes as capi
|
|
from django.contrib.gis.geos.error import GEOSException
|
|
from django.contrib.gis.geos.geometry import GEOSGeometry, LinearGeometryMixin
|
|
from django.contrib.gis.geos.libgeos import GEOM_PTR, geos_version_tuple
|
|
from django.contrib.gis.geos.linestring import LinearRing, LineString
|
|
from django.contrib.gis.geos.point import Point
|
|
from django.contrib.gis.geos.polygon import Polygon
|
|
|
|
|
|
class GeometryCollection(GEOSGeometry):
|
|
_typeid = 7
|
|
|
|
def __init__(self, *args, **kwargs):
|
|
"Initialize a Geometry Collection from a sequence of Geometry objects."
|
|
# Checking the arguments
|
|
if len(args) == 1:
|
|
# If only one geometry provided or a list of geometries is provided
|
|
# in the first argument.
|
|
if isinstance(args[0], (tuple, list)):
|
|
init_geoms = args[0]
|
|
else:
|
|
init_geoms = args
|
|
else:
|
|
init_geoms = args
|
|
|
|
# Ensuring that only the permitted geometries are allowed in this collection
|
|
# this is moved to list mixin super class
|
|
self._check_allowed(init_geoms)
|
|
|
|
# Creating the geometry pointer array.
|
|
collection = self._create_collection(len(init_geoms), init_geoms)
|
|
super().__init__(collection, **kwargs)
|
|
|
|
def __iter__(self):
|
|
"Iterate over each Geometry in the Collection."
|
|
for i in range(len(self)):
|
|
yield self[i]
|
|
|
|
def __len__(self):
|
|
"Return the number of geometries in this Collection."
|
|
return self.num_geom
|
|
|
|
# ### Methods for compatibility with ListMixin ###
|
|
def _create_collection(self, length, items):
|
|
# Creating the geometry pointer array.
|
|
geoms = (GEOM_PTR * length)(*[
|
|
# this is a little sloppy, but makes life easier
|
|
# allow GEOSGeometry types (python wrappers) or pointer types
|
|
capi.geom_clone(getattr(g, 'ptr', g)) for g in items
|
|
])
|
|
return capi.create_collection(c_int(self._typeid), byref(geoms), c_uint(length))
|
|
|
|
def _get_single_internal(self, index):
|
|
return capi.get_geomn(self.ptr, index)
|
|
|
|
def _get_single_external(self, index):
|
|
"Return the Geometry from this Collection at the given index (0-based)."
|
|
# Checking the index and returning the corresponding GEOS geometry.
|
|
return GEOSGeometry(capi.geom_clone(self._get_single_internal(index)), srid=self.srid)
|
|
|
|
def _set_list(self, length, items):
|
|
"Create a new collection, and destroy the contents of the previous pointer."
|
|
prev_ptr = self.ptr
|
|
srid = self.srid
|
|
self.ptr = self._create_collection(length, items)
|
|
if srid:
|
|
self.srid = srid
|
|
capi.destroy_geom(prev_ptr)
|
|
|
|
_set_single = GEOSGeometry._set_single_rebuild
|
|
_assign_extended_slice = GEOSGeometry._assign_extended_slice_rebuild
|
|
|
|
@property
|
|
def kml(self):
|
|
"Return the KML for this Geometry Collection."
|
|
return '<MultiGeometry>%s</MultiGeometry>' % ''.join(g.kml for g in self)
|
|
|
|
@property
|
|
def tuple(self):
|
|
"Return a tuple of all the coordinates in this Geometry Collection"
|
|
return tuple(g.tuple for g in self)
|
|
coords = tuple
|
|
|
|
|
|
# MultiPoint, MultiLineString, and MultiPolygon class definitions.
|
|
class MultiPoint(GeometryCollection):
|
|
_allowed = Point
|
|
_typeid = 4
|
|
|
|
|
|
class MultiLineString(LinearGeometryMixin, GeometryCollection):
|
|
_allowed = (LineString, LinearRing)
|
|
_typeid = 5
|
|
|
|
@property
|
|
def closed(self):
|
|
if geos_version_tuple() < (3, 5):
|
|
raise GEOSException("MultiLineString.closed requires GEOS >= 3.5.0.")
|
|
return super().closed
|
|
|
|
|
|
class MultiPolygon(GeometryCollection):
|
|
_allowed = Polygon
|
|
_typeid = 6
|
|
|
|
|
|
# Setting the allowed types here since GeometryCollection is defined before
|
|
# its subclasses.
|
|
GeometryCollection._allowed = (Point, LineString, LinearRing, Polygon, MultiPoint, MultiLineString, MultiPolygon)
|