-
Notifications
You must be signed in to change notification settings - Fork 0
/
split_lines.rs
83 lines (72 loc) · 2.45 KB
/
split_lines.rs
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
use std::collections::HashMap;
use geo::{Line, LineIntersection, LineLocatePoint, LineString};
use utils::LineSplit;
/// Given a bunch of linestrings, split them into smaller pieces when they cross.
pub fn split_crossing_linestrings(mut input: Vec<LineString>) -> Vec<LineString> {
let mut all_lines = Vec::new();
for (idx, linestring) in input.iter().enumerate() {
for line in linestring.lines() {
all_lines.push(LineWithData { line, idx });
}
}
// For every linestring, find all fractions where a split is needed
let mut split_fractions: HashMap<usize, Vec<f64>> = HashMap::new();
for (obj1, obj2, cross) in geo::sweep::Intersections::<_>::from_iter(all_lines) {
let LineIntersection::SinglePoint {
intersection,
is_proper,
} = cross
else {
continue;
};
// Intersections are expected constantly at endpoints, so ignore those
if !is_proper {
continue;
}
let ls1_fraction = input[obj1.idx]
.line_locate_point(&intersection.into())
.unwrap();
split_fractions
.entry(obj1.idx)
.or_insert_with(Vec::new)
.push(ls1_fraction);
let ls2_fraction = input[obj2.idx]
.line_locate_point(&intersection.into())
.unwrap();
split_fractions
.entry(obj2.idx)
.or_insert_with(Vec::new)
.push(ls2_fraction);
}
// Now split the linestrings at all places needed
let mut remove_old_linestrings = Vec::new();
for (idx, fractions) in split_fractions {
for split_ls in input[idx].line_split_many(&fractions).unwrap() {
let Some(split_ls) = split_ls else {
// Sometimes the split points are too close together
continue;
};
input.push(split_ls);
}
remove_old_linestrings.push(idx);
}
// Remove all linestrings we split. Since we're deleting by index/position, do the deletions in
// reverse order
remove_old_linestrings.sort();
remove_old_linestrings.reverse();
for idx in remove_old_linestrings {
input.remove(idx);
}
input
}
#[derive(Clone, Debug)]
struct LineWithData {
line: Line,
idx: usize,
}
impl geo::sweep::Cross for LineWithData {
type Scalar = f64;
fn line(&self) -> geo::sweep::LineOrPoint<Self::Scalar> {
self.line.line()
}
}