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Cleaned up geometry libraries

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This commit is contained in:
Anthony Wang 2020-08-12 09:29:40 -05:00
parent 3b88ee3957
commit ee5f54689c
2 changed files with 6 additions and 6 deletions
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4
Geometry/points_lines_vectors.cpp
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@ -27,7 +27,7 @@ double angle(point a, point o, point b) {
return acos(dot(oa, ob) / sqrt(norm_sq(oa) * norm_sq(ob)));
}
// (q.x - p.x) * (r.y - p.y) - (r.x - p.x) * (q.y - p.y)
// bool ccw(pl p, pl q, pl r) { return (q.f - p.f) * (r.s - p.s) - (r.f - p.f) * (q.s - p.s) > 0; }
bool ccw(point p, point q, point r) { return cross(vec(p, q), vec(p, r)) > 0; }
struct line {
@ -71,4 +71,4 @@ double point_to_seg(point p, seg s) {
bool seg_isect(seg a, seg b) {
return ccw(a.p1, a.p2, b.p1) * ccw(a.p1, a.p2, b.p2) <= 0 && ccw(b.p1, b.p2, a.p1) * ccw(b.p1, b.p2, a.p2) <= 0);
}
}

8
Geometry/polygons.cpp
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@ -1,5 +1,5 @@
struct point {
ll x, y; // long long to avoid overflow problems
ll x, y;
point() { x = y = 0; }
point(ll _x, ll _y) : x(_x), y(_y) {}
bool operator < (point p) const { return (x == p.x && y < p.y) || x < p.x; }
@ -27,7 +27,7 @@ double angle(point a, point o, point b) {
bool ccw(point p, point q, point r) { return cross(vec(p, q), vec(p, r)) > 0; }
bool in_polygon(point pt, const vector<point>& P) {
bool in_polygon(point pt, const vector<point> & P) {
double sum = 0;
for (int i = 0; i < P.size() - 1; i++) {
if (pt == P[i]) return true;
@ -36,14 +36,14 @@ bool in_polygon(point pt, const vector<point>& P) {
return fabs(sum) > acos(-1.0);
}
ll area(const vector<point>& P) {
ll area(const vector<point> & P) {
ll res = 0;
for (int i = 0; i < (int)P.size() - 1; i++) res += (P[i].x * P[i + 1].y - P[i + 1].x * P[i].y);
return res;
// return res / 2.0;
}
vector<point> convex_hull(vector<point>& P) {
vector<point> convex_hull(vector<point> & P) {
int n = P.size(), k = 0;
vector<point> H(2 * n);
sort(P.begin(), P.end());