def geom_to_bbox(geom, min_area=0):
from kartograph.geometry import BBox
from shapely.geometry import MultiPolygon
if True or min_area == 0 or not isinstance(geom, MultiPolygon):
# if no minimum area ratio is set or the geometry
# is not a multipart geometry, we simply use the
# full bbox
minx, miny, maxx, maxy = geom.bounds
return BBox(width=maxx - minx, height=maxy - miny, left=minx, top=miny)
else:
# for multipart geometry we use only the bbox of
# the 'biggest' sub-geometries, depending on min_area
bbox = BBox()
areas = []
bb = []
for polygon in geom.geoms:
areas.append(polygon.area)
max_a = max(areas)
for i in range(len(geom.geoms)):
a = areas[i]
if a < max_a * min_area:
# ignore this sub polygon since it is too small
continue
bb.append(geom.geoms[i].bounds)
for b in bb:
bbox.update((b[0], b[2]))
bbox.update((b[1], b[2]))
bbox.update((b[0], b[3]))
bbox.update((b[1], b[3]))
return bbox
def geom_to_bbox(geom, min_area=0):
from kartograph.geometry import BBox
from shapely.geometry import MultiPolygon
if True or min_area == 0 or not isinstance(geom, MultiPolygon):
# if no minimum area ratio is set or the geometry
# is not a multipart geometry, we simply use the
# full bbox
minx, miny, maxx, maxy = geom.bounds
return BBox(width=maxx - minx, height=maxy - miny, left=minx, top=miny)
else:
# for multipart geometry we use only the bbox of
# the 'biggest' sub-geometries, depending on min_area
bbox = BBox()
areas = []
bb = []
for polygon in geom.geoms:
areas.append(polygon.area)
max_a = max(areas)
for i in range(len(geom.geoms)):
a = areas[i]
if a < max_a * min_area:
# ignore this sub polygon since it is too small
continue
bb.append(geom.geoms[i].bounds)
for b in bb:
bbox.update((b[0], b[2]))
bbox.update((b[1], b[2]))
bbox.update((b[0], b[3]))
bbox.update((b[1], b[3]))
return bbox
def shape2polygon(shp, ignore_holes=False, min_area=False, proj=None):
"""
converts a shapefile polygon to geometry.MultiPolygon
"""
# from kartograph.geometry import MultiPolygon
from shapely.geometry import Polygon, MultiPolygon
from kartograph.geometry.utils import is_clockwise
parts = shp.parts[:]
parts.append(len(shp.points))
exteriors = []
holes = []
for j in range(len(parts) - 1):
pts = shp.points[parts[j]:parts[j + 1]]
if shp.shapeType == 15:
# remove z-coordinate from PolygonZ contours (not supported)
for k in range(len(pts)):
pts[k] = pts[k][:2]
if proj:
project_coords(pts, proj)
cw = is_clockwise(pts)
if cw:
exteriors.append(pts)
else:
holes.append(pts)
if ignore_holes:
holes = None
if len(exteriors) == 1:
poly = Polygon(exteriors[0], holes)
elif len(exteriors) > 1:
# use multipolygon, but we need to assign the holes to the right
# exteriors
from kartograph.geometry import BBox
used_holes = set()
polygons = []
for ext in exteriors:
bbox = BBox()
my_holes = []
for pt in ext:
bbox.update(pt)
for h in range(len(holes)):
if h not in used_holes:
hole = holes[h]
if bbox.check_point(hole[0]):
# this is a very weak test but it should be sufficient
used_holes.add(h)
my_holes.append(hole)
polygons.append(Polygon(ext, my_holes))
if min_area:
# compute maximum area
max_area = 0
for poly in polygons:
max_area = max(max_area, poly.area)
# filter out polygons that are below min_area * max_area
polygons = [poly for poly in polygons if poly.area >= min_area * max_area]
poly = MultiPolygon(polygons)
else:
raise KartographError('shapefile import failed - no outer polygon found')
return poly
def shape2polygon(shp, ignore_holes=False, min_area=False, proj=None):
"""
converts a shapefile polygon to geometry.MultiPolygon
"""
# from kartograph.geometry import MultiPolygon
from shapely.geometry import Polygon, MultiPolygon
from kartograph.geometry.utils import is_clockwise
parts = shp.parts[:]
parts.append(len(shp.points))
exteriors = []
holes = []
for j in range(len(parts) - 1):
pts = shp.points[parts[j]:parts[j + 1]]
if shp.shapeType == 15:
# remove z-coordinate from PolygonZ contours (not supported)
for k in range(len(pts)):
pts[k] = pts[k][:2]
if proj:
project_coords(pts, proj)
cw = is_clockwise(pts)
if cw:
exteriors.append(pts)
else:
holes.append(pts)
if ignore_holes:
holes = None
if len(exteriors) == 1:
poly = Polygon(exteriors[0], holes)
elif len(exteriors) > 1:
# use multipolygon, but we need to assign the holes to the right
# exteriors
from kartograph.geometry import BBox
used_holes = set()
polygons = []
for ext in exteriors:
bbox = BBox()
my_holes = []
for pt in ext:
bbox.update(pt)
for h in range(len(holes)):
if h not in used_holes:
hole = holes[h]
if bbox.check_point(hole[0]):
# this is a very weak test but it should be sufficient
used_holes.add(h)
my_holes.append(hole)
polygons.append(Polygon(ext, my_holes))
if min_area:
# compute maximum area
max_area = 0
for poly in polygons:
max_area = max(max_area, poly.area)
# filter out polygons that are below min_area * max_area
polygons = [poly for poly in polygons if poly.area >= min_area * max_area]
poly = MultiPolygon(polygons)
else:
raise KartographError('shapefile import failed - no outer polygon found')
return poly
def shape2polygon(shp, ignore_holes=False, min_area=False, proj=None):
"""
converts a shapefile polygon to geometry.MultiPolygon
"""
# ignore_holes=True
# from kartograph.geometry import MultiPolygon
from shapely.geometry import Polygon, MultiPolygon
from kartograph.geometry.utils import is_clockwise
parts = shp.parts[:]
parts.append(len(shp.points))
exteriors = []
rep_point = None
holes = []
# print 'shp.the_feat_name={0}'.format(shp.the_feat_name)
# print 'shp.represenative_points={0}'.format(shp.representative_point())
for j in range(len(parts) - 1):
pts = shp.points[parts[j]:parts[j + 1]]
if shp.shapeType == 15:
# remove z-coordinate from PolygonZ contours (not supported)
for k in range(len(pts)):
pts[k] = pts[k][:2]
if proj and shp.alreadyProj is False:
project_coords(pts, proj, rep_point=rep_point)
if shp.bounding:
# print 'Already proj, proj exists'
shp.alreadyProj = True
elif shp.alreadyProj is False:
if shp.bounding:
shp.alreadyProj = True
#else:
# print 'shp.bounding={0}'.format(shp.bounding)
# print 'Already proj, no proj exists'
cw = is_clockwise(pts)
if cw:
exteriors.append(pts)
else:
holes.append(pts)
if ignore_holes:
print 'ignoring holes'
holes = None
# if len(holes) > 0:
# print '\tThere are {0} holes'.format(len(holes))
if len(exteriors) == 1:
# print 'Single polygon, {0}'.format(shp.the_feat_name)
poly = Polygon(exteriors[0], holes)
elif len(exteriors) > 1:
# print 'Multipolygon, {0}'.format(shp.the_feat_name)
# use multipolygon, but we need to assign the holes to the right
# exteriors
from kartograph.geometry import BBox
used_holes = set()
polygons = []
for ext in exteriors:
bbox = BBox()
my_holes = []
for pt in ext:
bbox.update(pt)
for h in range(len(holes)):
if h not in used_holes:
hole = holes[h]
if bbox.check_point(hole[0]):
# this is a very weak test but it should be sufficient
used_holes.add(h)
my_holes.append(hole)
polygons.append(Polygon(ext, my_holes))
if min_area:
# compute maximum area
max_area = 0
for poly in polygons:
max_area = max(max_area, poly.area)
# filter out polygons that are below min_area * max_area
polygons = [
poly for poly in polygons if poly.area >= min_area * max_area
]
poly = MultiPolygon(polygons)
else:
# return None
raise KartographError(
'shapefile import failed - no outer polygon found')
# print 'poly={0}'.format(poly)
return poly
