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-rw-r--r--geometry/segmentIntersection.cpp63
1 files changed, 0 insertions, 63 deletions
diff --git a/geometry/segmentIntersection.cpp b/geometry/segmentIntersection.cpp
deleted file mode 100644
index 6dc5dc5..0000000
--- a/geometry/segmentIntersection.cpp
+++ /dev/null
@@ -1,63 +0,0 @@
-struct seg {
- pt a, b;
- int id;
- bool operator<(const seg& o) const {
- if (real(a) < real(o.a)) {
- int s = orientation(a, b, o.a);
- return (s > 0 || (s == 0 && imag(a) < imag(o.a)));
- } else if (real(a) > real(o.a)) {
- int s = orientation(o.a, o.b, a);
- return (s < 0 || (s == 0 && imag(a) < imag(o.a)));
- }
- return imag(a) < imag(o.a);
- }
-};
-
-struct event {
- pt p;
- int id, type;
- bool operator<(const event& o) const {
- if (real(p) != real(o.p)) return real(p) < real(o.p);
- if (type != o.type) return type > o.type;
- return imag(p) < imag(o.p);
- }
-};
-
-bool lessPT(const pt& a, const pt& b) {
- return real(a) != real(b) ? real(a) < real(b)
- : imag(a) < imag(b);
-}
-
-bool intersect(const seg& a, const seg& b) {
- return lineSegmentIntersection(a.a, a.b, b.a, b.b);
-}
-
-pair<int, int> intersect(vector<seg>& segs) {
- vector<event> events;
- for (seg& s : segs) {
- if (lessPT(s.b, s.a)) swap(s.b, s.a);
- events.push_back({s.a, s.id, 1});
- events.push_back({s.b, s.id, -1});
- }
- sort(all(events));
-
- set<seg> q;
- vector<set<seg>::iterator> where(sz(segs));
- for (auto e : events) {
- int id = e.id;
- if (e.type > 0) {
- auto it = q.lower_bound(segs[id]);
- if (it != q.end() && intersect(*it, segs[id]))
- return {it->id, segs[id].id};
- if (it != q.begin() && intersect(*prev(it), segs[id]))
- return {prev(it)->id, segs[id].id};
- where[id] = q.insert(it, segs[id]);
- } else {
- auto it = where[id];
- if (it != q.begin() && next(it) != q.end() && intersect(*next(it), *prev(it)))
- return {next(it)->id, prev(it)->id};
- q.erase(it);
- }
- }
- return {-1, -1};
-}