def merge(tree, tol=0.1):
"""Remove inner branches that are short, combining branchpoints as needed."""
for node in list(tree.preOrder()):
if node.segment.length < tol:
logging.info(
" ...cleaned inner segment of length %g at centroid %r" %
(node.segment.length, node.segment.centroid.coords[0]))
for child in node.children:
child.segment = shapely.geometry.LineString(
child.segment.coords[:-1] + [
node.parent.segment.coords[0],
])
node.parent.addChild(child)
node.remove()
def simplify(tree, tol=0.1):
"""Simplify, IN PLACE, all tree segments."""
for node in tree.preOrder():
if node.segment is not None:
node.segment = node.segment.simplify(tol)
def snap_endpoints(tree, hucs, tol=0.1):
"""Snap river endpoints to huc segments and insert that point into
the boundary.
Note this is O(n^2), and could be made more efficient.
"""
to_add = []
for node in tree.preOrder():
river = node.segment
for b, component in itertools.chain(hucs.boundaries.items(),
hucs.intersections.items()):
# note, this is done in two stages to allow it deal with both endpoints touching
for s, seg_handle in component.items():
seg = hucs.segments[seg_handle]
#logging.debug("SNAP P0:")
#logging.debug(" huc seg: %r"%seg.coords[:])
#logging.debug(" river: %r"%river.coords[:])
altered = False
logging.debug(" - checking river coord: %r" %
list(river.coords[0]))
logging.debug(" - seg coords: {0}".format(list(seg.coords)))
new_coord = _snap_and_cut(river.coords[0], seg, tol)
logging.debug(" - new coord: {0}".format(new_coord))
if new_coord is not None:
logging.info(" snapped river: %r to %r" %
(river.coords[0], new_coord))
# move new_coord onto an existing segment coord
dist = np.linalg.norm(np.array(seg.coords) -
np.expand_dims(new_coord, 0),
2,
axis=1)
assert (len(dist) == len(seg.coords))
assert (len(dist.shape) == 1)
i = int(np.argmin(dist))
if (dist[i] < tol):
new_coord = seg.coords[i]
# remove points that are closer
coords = list(river.coords)
done = False
while len(coords) > 2 and workflow.utils.distance(new_coord, coords[1]) < \
workflow.utils.distance(new_coord, coords[0]):
coords.pop(0)
coords[0] = new_coord
river = shapely.geometry.LineString(coords)
node.segment = river
to_add.append((seg_handle, component, 0, node))
break
# second stage
for s, seg_handle in component.items():
seg = hucs.segments[seg_handle]
# logging.debug("SNAP P1:")
# logging.debug(" huc seg: %r"%seg.coords[:])
# logging.debug(" river: %r"%river.coords[:])
altered = False
logging.debug(" - checking river coord: %r" %
list(river.coords[-1]))
logging.debug(" - seg coords: {0}".format(list(seg.coords)))
new_coord = _snap_and_cut(river.coords[-1], seg, tol)
logging.debug(" - new coord: {0}".format(new_coord))
if new_coord is not None:
logging.info(" - snapped river: %r to %r" %
(river.coords[-1], new_coord))
# move new_coord onto an existing segment coord
dist = np.linalg.norm(np.array(seg.coords) -
np.expand_dims(new_coord, 0),
2,
axis=1)
assert (len(dist) == len(seg.coords))
assert (len(dist.shape) == 1)
i = int(np.argmin(dist))
if (dist[i] < tol):
new_coord = seg.coords[i]
# remove points that are closer
coords = list(river.coords)
done = False
while len(coords) > 2 and workflow.utils.distance(new_coord, coords[-2]) < \
workflow.utils.distance(new_coord, coords[-1]):
coords.pop(-1)
coords[-1] = new_coord
river = shapely.geometry.LineString(coords)
node.segment = river
to_add.append((seg_handle, component, -1, node))
break
# find the list of points to add to a given segment
to_add_dict = dict()
for seg_handle, component, endpoint, node in to_add:
if seg_handle not in to_add_dict.keys():
to_add_dict[seg_handle] = list()
to_add_dict[seg_handle].append((component, endpoint, node))
# find the set of points to add to each given segment
def equal(p1, p2):
if workflow.utils.close(p1[2].segment.coords[p1[1]],
p2[2].segment.coords[p2[1]], 1.e-5):
assert (p1[0] == p2[0])
return True
else:
return False
to_add_dict2 = dict()
for seg_handle, insert_list in to_add_dict.items():
new_list = []
for p1 in insert_list:
if (all(not equal(p1, p2) for p2 in new_list)):
new_list.append(p1)
to_add_dict2[seg_handle] = new_list
# add these points to the segment
for seg_handle, insert_list in to_add_dict2.items():
seg = hucs.segments[seg_handle]
# make a list of the coords and a flag to indicate a new
# coord, then sort it by arclength along the segment.
#
# Note this needs special care if the seg is a loop, or else the endpoint gets sorted twice
if not workflow.utils.close(seg.coords[0], seg.coords[-1]):
new_coords = [[p[2].segment.coords[p[1]], 1] for p in insert_list]
old_coords = [[c, 0] for c in seg.coords if not any(
workflow.utils.close(c, nc, tol) for nc in new_coords)]
new_seg_coords = sorted(
new_coords + old_coords,
key=lambda a: seg.project(shapely.geometry.Point(a)))
# determine the new coordinate indices
breakpoint_inds = [
i for i, (c, f) in enumerate(new_seg_coords) if f is 1
]
else:
new_coords = [[p[2].segment.coords[p[1]], 1] for p in insert_list]
old_coords = [[c, 0] for c in seg.coords[:-1] if not any(
workflow.utils.close(c, nc, tol) for nc in new_coords)]
new_seg_coords = sorted(
new_coords + old_coords,
key=lambda a: seg.project(shapely.geometry.Point(a)))
breakpoint_inds = [
i for i, (c, f) in enumerate(new_seg_coords) if f is 1
]
assert (len(breakpoint_inds) > 0)
new_seg_coords = new_seg_coords[
breakpoint_inds[0]:] + new_seg_coords[0:breakpoint_inds[0] + 1]
new_seg_coords[0][1] = 0
new_seg_coords[-1][1] = 0
breakpoint_inds = [
i for i, (c, f) in enumerate(new_seg_coords) if f is 1
]
# now break into new segments
new_segs = []
ind_start = 0
for ind_end in breakpoint_inds:
assert (ind_end is not 0)
new_segs.append(
shapely.geometry.LineString(
[c for (c, f) in new_seg_coords[ind_start:ind_end + 1]]))
ind_start = ind_end
assert (ind_start < len(new_seg_coords) - 1)
new_segs.append(
shapely.geometry.LineString(
[tuple(c) for (c, f) in new_seg_coords[ind_start:]]))
# put all new_segs into the huc list. Note insert_list[0][0] is the component
hucs.segments[seg_handle] = new_segs.pop(0)
new_handles = hucs.segments.add_many(new_segs)
insert_list[0][0].add_many(new_handles)
return river
def snap_crossings(hucs, rivers, tol=0.1):
"""Snaps HUC boundaries and rivers to crossings."""
for tree in rivers:
for river_node in tree.preOrder():
_snap_crossing(hucs, river_node, tol)