-
Notifications
You must be signed in to change notification settings - Fork 5
/
snap.py
243 lines (211 loc) · 7.43 KB
/
snap.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
import math
import numpy as np
import pygeos
import operator
import geopandas as gpd
def get_extrapolated_line(coords, tolerance, point=False):
"""
Creates a line extrapoled in p1->p2 direction.
"""
p1 = coords[:2]
p2 = coords[2:]
a = p2
# defining new point based on the vector between existing points
if p1[0] >= p2[0] and p1[1] >= p2[1]:
b = (
p2[0]
- tolerance
* math.cos(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
p2[1]
- tolerance
* math.sin(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
)
elif p1[0] <= p2[0] and p1[1] >= p2[1]:
b = (
p2[0]
+ tolerance
* math.cos(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
p2[1]
- tolerance
* math.sin(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
)
elif p1[0] <= p2[0] and p1[1] <= p2[1]:
b = (
p2[0]
+ tolerance
* math.cos(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
p2[1]
+ tolerance
* math.sin(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
)
else:
b = (
p2[0]
- tolerance
* math.cos(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
p2[1]
+ tolerance
* math.sin(
math.atan(
math.fabs(p1[1] - p2[1] + 0.000001)
/ math.fabs(p1[0] - p2[0] + 0.000001)
)
),
)
if point:
return b
return pygeos.linestrings([a, b])
def line_to_line(gdf, target, tolerance):
""" Extends lines from gdf to target within a set tolerance
"""
# explode to avoid MultiLineStrings
# double reset index due to the bug in GeoPandas explode
df = gdf.reset_index(drop=True).explode().reset_index(drop=True)
# get underlying pygeos geometry
geom = df.geometry.values.data
# extract array of coordinates and number per geometry
coords = pygeos.get_coordinates(geom)
indices = pygeos.get_num_coordinates(geom)
# generate a list of start and end coordinates and create point geometries
edges = [0]
i = 0
for ind in indices:
ix = i + ind
edges.append(ix - 1)
edges.append(ix)
i = ix
edges = edges[:-1]
points = pygeos.points(np.unique(coords[edges], axis=0))
# query LineString geometry to identify points intersecting 2 geometries
tree = pygeos.STRtree(geom)
inp, res = tree.query_bulk(points, predicate="intersects")
unique, counts = np.unique(inp, return_counts=True)
ends = np.unique(res[np.isin(inp, unique[counts == 1])])
new_geoms = []
# iterate over cul-de-sac-like segments and attempt to snap them to street network
for line in ends:
l_coords = pygeos.get_coordinates(geom[line])
start = pygeos.points(l_coords[0])
end = pygeos.points(l_coords[-1])
first = list(tree.query(start, predicate="intersects"))
second = list(tree.query(end, predicate="intersects"))
first.remove(line)
second.remove(line)
if first and not second:
snapped = extend_line(l_coords, target, tolerance)
new_geoms.append(
pygeos.linestrings(extend_line(snapped, target, 0.00001, snap=False))
)
elif not first and second:
snapped = extend_line(np.flip(l_coords, axis=0), target, tolerance)
new_geoms.append(
pygeos.linestrings(extend_line(snapped, target, 0.00001, snap=False))
)
elif not first and not second:
one_side = extend_line(l_coords, target, tolerance)
one_side_e = extend_line(one_side, target, 0.00001, snap=False)
snapped = extend_line(np.flip(one_side_e, axis=0), target, tolerance)
new_geoms.append(
pygeos.linestrings(extend_line(snapped, target, 0.00001, snap=False))
)
df = df.drop(ends)
final = gpd.GeoSeries(new_geoms).explode().reset_index(drop=True)
return df.append(
gpd.GeoDataFrame({df.geometry.name: final}, geometry=df.geometry.name),
ignore_index=True,
)
def extend_line(coords, target, tolerance, snap=True):
"""
Extends a line geometry to snap on the target within a tolerance.
"""
if snap:
extrapolation = get_extrapolated_line(
coords[-4:] if len(coords.shape) == 1 else coords[-2:].flatten(), tolerance
)
int_idx = target.sindex.query(extrapolation, predicate="intersects")
intersection = pygeos.intersection(
target.iloc[int_idx].geometry.values.data, extrapolation
)
if intersection.size > 0:
if len(intersection) > 1:
distances = {}
ix = 0
for p in intersection:
distance = pygeos.distance(p, pygeos.points(coords[-1]))
distances[ix] = distance
ix = ix + 1
minimal = min(distances.items(), key=operator.itemgetter(1))[0]
new_point_coords = pygeos.get_coordinates(intersection[minimal])
else:
new_point_coords = pygeos.get_coordinates(intersection[0])
coo = np.append(coords, new_point_coords)
new = np.reshape(coo, (int(len(coo) / 2), 2))
return new
return coords
extrapolation = get_extrapolated_line(
coords[-4:] if len(coords.shape) == 1 else coords[-2:].flatten(),
tolerance,
point=True,
)
return np.vstack([coords, extrapolation])
def close_gaps(df, tolerance):
"""Close gaps in LineString geometry where it should be contiguous.
Snaps both lines to a centroid of a gap in between.
"""
geom = df.geometry.values.data
coords = pygeos.get_coordinates(geom)
indices = pygeos.get_num_coordinates(geom)
# generate a list of start and end coordinates and create point geometries
edges = [0]
i = 0
for ind in indices:
ix = i + ind
edges.append(ix - 1)
edges.append(ix)
i = ix
edges = edges[:-1]
points = pygeos.points(np.unique(coords[edges], axis=0))
buffered = pygeos.buffer(points, tolerance)
dissolved = pygeos.union_all(buffered)
exploded = [
pygeos.get_geometry(dissolved, i)
for i in range(pygeos.get_num_geometries(dissolved))
]
centroids = pygeos.centroid(exploded)
snapped = pygeos.snap(geom, pygeos.union_all(centroids), tolerance)
return snapped