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authorGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
committerGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
commit98567ec798aa8ca2cfbcb85c774dd470f30e30d4 (patch)
tree5113d5cc24d1ad5f93810b6442ce584a36950dc8 /geometry/hpi.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'geometry/hpi.cpp')
-rw-r--r--geometry/hpi.cpp68
1 files changed, 0 insertions, 68 deletions
diff --git a/geometry/hpi.cpp b/geometry/hpi.cpp
deleted file mode 100644
index 3509e0e..0000000
--- a/geometry/hpi.cpp
+++ /dev/null
@@ -1,68 +0,0 @@
-constexpr ll inf = 0x1FFF'FFFF'FFFF'FFFF;//THIS CODE IS WIP
-
-bool left(pt p) {return real(p) < 0 ||
- (real(p) == 0 && imag(p) < 0);}
-struct hp {
- pt from, to;
-
- hp(pt a, pt b) : from(a), to(b) {}
- hp(pt dummy) : hp(dummy, dummy) {}
-
- bool dummy() const {return from == to;}
- pt dir() const {return dummy() ? to : to - from;}
- bool operator<(const hp& o) const {
- if (left(dir()) != left(o.dir()))
- return left(dir()) > left(o.dir());
- return cross(dir(), o.dir()) > 0;
- }
-
- using lll = __int128;
- using ptl = complex<lll>;
- ptl mul(lll m, ptl p) const {return m*p;}//ensure 128bit
-
- bool check(const hp& a, const hp& b) const {
- if (dummy() || b.dummy()) return false;
- if (a.dummy()) {
- ll ort = sgn(cross(b.dir(), dir()));
- if (ort == 0) return cross(from, to, a.from) < 0;
- return cross(b.dir(), a.dir()) * ort > 0;
- }
- ll y = cross(a.dir(), b.dir());
- ll z = cross(b.from - a.from, b.dir());
- ptl i = mul(y, a.from) + mul(z, a.dir()); //intersect a and b
- // check if i is outside/right of x
- return imag(conj(mul(sgn(y),dir()))*(i-mul(y,from))) < 0;
- }
-};
-
-constexpr ll lim = 2e9+7;
-
-deque<hp> intersect(vector<hp> hps) {
- hps.push_back(hp(pt{lim+1,-1}));
- hps.push_back(hp(pt{lim+1,1}));
- sort(all(hps));
-
- deque<hp> dq = {hp(pt{-lim, 1})};
- for (auto x : hps) {
- while (sz(dq) > 1 && x.check(dq.end()[-1], dq.end()[-2]))
- dq.pop_back();
- while (sz(dq) > 1 && x.check(dq[0], dq[1]))
- dq.pop_front();
-
- if (cross(x.dir(), dq.back().dir()) == 0) {
- if (dot(x.dir(), dq.back().dir()) < 0) return {};
- if (cross(x.from, x.to, dq.back().from) < 0)
- dq.pop_back();
- else continue;
- }
- dq.push_back(x);
- }
-
- while (sz(dq) > 2 && dq[0].check(dq.end()[-1], dq.end()[-2]))
- dq.pop_back();
- while (sz(dq) > 2 && dq.end()[-1].check(dq[0], dq[1]))
- dq.pop_front();
-
- if (sz(dq) < 3) return {};
- return dq;
-}