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
import ../types
import json
import options
import math
proc gpsDistance(fromLat: float, fromLon: float, toLat: float, toLon: float): float =
proc toRad(x: float): float = x * PI / 180
let dLat = toRad(toLat - fromLat)
let dLon = toRad(toLon - fromLon)
let fromLat = toRad(fromLat)
let toLat = toRad(toLat)
let a = pow(sin(dLat / 2), 2) + (pow(sin(dLon / 2), 2) * cos(fromLat) * cos(toLat))
let c = 2 * arctan2(sqrt(a), sqrt(1 - a))
return 6371 * c
proc parseIntegers(str: string): seq[int] =
var byte = 0
var current = 0
var bits = 0
for c in str:
byte = int(c) - 63
current = current or (( byte and 31 ) shl bits)
bits += 5
if byte < 32:
if (current and 1) == 1:
current = -current
current = current shr 1
result.add(current)
current = 0
bits = 0
proc mkParsePolyline*(points: seq[Point]): proc =
proc parsePolyline(l: JsonNode): Polyline =
let line = l.to(HafasPolyLine)
result.type = "FeatureCollection"
var lat = 0
var lon = 0
let ints = parseIntegers(line.crdEncYX)
var i = 0
while i < len(ints):
lat += ints[i]
lon += ints[i+1]
result.features.add(Feature(
type: "Feature",
geometry: FeatureGeometry(
type: "Point",
coordinates: @[lon / 100000, lat / 100000],
),
))
i += 2
if line.ppLocRefL.isSome:
for p in line.ppLocRefL.get:
result.features[p.ppIdx].properties = points[p.locX].stop
# sort out coordinates closer than 5m to their neighbours
var j = 1
while true:
if j >= len(result.features): break
let last = result.features[j-1].geometry.coordinates
let current = result.features[j].geometry.coordinates
if gpsDistance(last[1], last[0], current[1], current[0]) <= 0.005:
result.features.delete(j)
continue
j += 1
return parsePolyline