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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 /test/geometry/polygon.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'test/geometry/polygon.cpp')
-rw-r--r--test/geometry/polygon.cpp296
1 files changed, 296 insertions, 0 deletions
diff --git a/test/geometry/polygon.cpp b/test/geometry/polygon.cpp
new file mode 100644
index 0000000..1dd46ca
--- /dev/null
+++ b/test/geometry/polygon.cpp
@@ -0,0 +1,296 @@
+#include "../util.h"
+constexpr ll EPS = 0;
+constexpr double INF = LD::INF;
+#define double ll
+#define polar polar<ll>
+#include <geometry/formulas.cpp>
+#undef polar
+#undef double
+double abs(pt p) {
+ return hypot(real(p), imag(p));
+}
+// Liegt p auf der Strecke a-b?
+bool pointOnLineSegment(pt a, pt b, pt p) {
+ if (cross(a, b, p) != 0) return false;
+ auto dist = norm(a - b);
+ return norm(a - p) <= dist && norm(b - p) <= dist;
+}
+// Entfernung von Punkt p zur Strecke a-b.
+double distToSegment(pt a, pt b, pt p) {
+ if (a == b) return abs(p - a);
+ if (dot(p - a, b - a) <= 0) return abs(p - a);
+ if (dot(p - b, b - a) >= 0) return abs(p - b);
+ return abs(cross(p - a, b - a)) / abs(b - a);
+}
+#pragma GCC diagnostic ignored "-Wunused-variable"
+#include <geometry/polygon.cpp>
+#include "../geometry.h"
+
+void test_area(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 30);
+ auto ps = Random::polygon(n, range);
+ ps.push_back(ps[0]);
+
+ ll expected = 0;
+ for (int i = 0; i < n; i++) {
+ expected += cross(0, ps[i], ps[i+1]);
+ }
+ double got = area(ps) * 2;
+ if (got != expected) cerr << "got: " << got << ", expected: " << expected << FAIL;
+ queries += n;
+ }
+ cerr << "tested area: " << queries << endl;
+}
+
+bool ptLess(pt a, pt b) {
+ if (real(a) != real(b)) return real(a) < real(b);
+ return imag(a) < imag(b);
+}
+
+void test_windingNumber(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 8);
+ auto ps = Random::polygon(n, range);
+ ps.push_back(ps[0]);
+
+ for (int i = 0; i < 100; i++) {
+ auto p = Random::point<ll>(-range, range);
+
+ ll expected = 0;
+ bool onBorder = false;
+ for (int j = 0; j < n; j++) {
+ int cur = details::lineSegmentIntersection(p, p + pt(1, 2'000'000'007), ps[j], ps[j+1]);
+ if (ptLess(ps[j], ps[j+1])) expected -= cur;
+ else expected += cur;
+ onBorder |= pointOnLineSegment(ps[j], ps[j+1], p);
+ }
+ if (onBorder) continue;
+ if (area(ps) < 0) expected = -expected;
+
+ bool got = windingNumber(p, ps);
+
+ if (got != expected) cerr << "got: " << got << ", expected: " << expected << FAIL;
+ }
+ queries += n;
+ }
+ cerr << "tested windingNumber: " << queries << endl;
+}
+
+void test_inside(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 30);
+ auto ps = Random::polygon(n, range);
+ ps.push_back(ps[0]);
+
+ for (int i = 0; i < 100; i++) {
+ auto p = Random::point<ll>(-range, range);
+
+ ll count = 0;
+ bool onBorder = false;
+ for (int j = 0; j < n; j++) {
+ count += details::lineSegmentIntersection(p, p + pt(1, 2'000'000'007), ps[j], ps[j+1]);
+ onBorder |= pointOnLineSegment(ps[j], ps[j+1], p);
+ }
+ bool expected = (count % 2) && !onBorder;
+ bool got = inside(p, ps);
+
+ if (got != expected) cerr << "error" << FAIL;
+ }
+ queries += n;
+ }
+ cerr << "tested inside: " << queries << endl;
+}
+
+void test_insideConvex(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 30);
+ auto ps = Random::convex(n, range);
+
+ for (int i = 0; i < 100; i++) {
+ auto p = Random::point<ll>(-range, range);
+
+ bool expected = true;
+ for (int j = 0; j < n; j++) expected &= cross(p, ps[j], ps[(j+1) % n]) > 0;
+
+ bool got = insideConvex(p, ps);
+
+ if (got != expected) {
+ for (pt pp : ps) cerr << pp << " ";
+ cerr << endl;
+ cerr << p << endl;
+ }
+
+ if (got != expected) cerr << "got: " << got << ", expected: " << expected << FAIL;
+ }
+ queries += n;
+ }
+ cerr << "tested insideConvex: " << queries << endl;
+}
+
+// convex hull without duplicates, h[0] != h.back()
+// apply comments if border counts as inside
+bool insideOrOnConvex(pt p, const vector<pt>& hull) {
+ int l = 0, r = sz(hull) - 1;
+ if (cross(hull[0], hull[r], p) > 0) return false;
+ while (l + 1 < r) {
+ int m = (l + r) / 2;
+ if (cross(hull[0], hull[m], p) >= 0) l = m;
+ else r = m;
+ }
+ return cross(hull[l], hull[r], p) >= 0;
+}
+
+void test_minkowski(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 30);
+ auto A = Random::convex(n, range);
+ int m = Random::integer(3, 30);
+ auto B = Random::convex(n, range);
+
+ auto got = minkowski(A, B);
+ bool convex = true;
+ for (int i = 0; i < sz(got); i++) convex &= cross(got[i], got[(i+1) % sz(got)], got[(i+2) % sz(got)]) >= 0;
+ if (!convex) cerr << "error: not convex" << FAIL;
+
+ for (pt a : A) {
+ for (pt b : B) {
+ if (!insideOrOnConvex(a + b, got)) cerr << "error: not sum" << FAIL;
+ }
+ }
+ queries += n + m;
+ }
+ cerr << "tested minkowski: " << queries << endl;
+}
+
+double naive_dist(const vector<pt>& ps, const vector<pt>& qs) {
+ //check if intersect
+ double res = LD::INF;
+ bool intersect = true;
+ for (int i = 0; i < sz(qs); i++) {
+ bool sep = true;
+ for (pt p : ps) {
+ res = min(res, distToSegment(qs[i], qs[(i+1) % sz(qs)], p));
+ sep &= cross(qs[i], qs[(i+1) % sz(qs)], p) <= 0;
+ }
+ if (sep) intersect = false;
+ }
+ for (int i = 0; i < sz(ps); i++) {
+ bool sep = true;
+ for (pt q : qs) {
+ res = min(res, distToSegment(ps[i], ps[(i+1) % sz(ps)], q));
+ sep &= cross(ps[i], ps[(i+1) % sz(ps)], q) <= 0;
+ }
+ if (sep) intersect = false;
+ }
+ if (intersect) return 0;
+ return res;
+}
+
+void test_dist(ll range) {
+ int queries = 0;
+ int pos = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 10);
+ auto A = Random::convex(n, range / 3);
+ int m = Random::integer(3, 10);
+ auto B = Random::convex(n, range / 3);
+
+ pt offset = Random::point<ll>(range / 3, 2 * range / 3);
+ for (pt& p : B) p += offset;
+
+ auto got = dist(A, B);
+ auto expected = naive_dist(A, B);
+
+ if (float_error(got, expected) > 1e-6) cerr << "got: " << got << ", expected: " << expected << FAIL;
+ if (got > 0) pos++;
+
+ queries += n + m;
+ }
+ cerr << "tested dist: " << queries << " (" << pos << ")" << endl;
+}
+
+void test_extremal(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 30);
+ auto ps = Random::convex(n, range);
+ ps.push_back(ps[0]);
+
+ for (int i = 0; i < 100; i++) {
+ auto dir = Random::point<ll>(-range, range);
+ int tmp = extremal(ps, dir);
+ if (tmp < 0 || tmp >= n) cerr << "error: out of range" << FAIL;
+
+ auto got = ps[tmp];
+ bool extremal = true;
+ for (pt p : ps) extremal &= dot(dir, p) <= dot(dir, got);
+
+ if (!extremal) cerr << "error: not extremal" << FAIL;
+ queries += n;
+ }
+ }
+ cerr << "tested extremal: " << queries << endl;
+}
+
+void test_intersect(ll range) {
+ int queries = 0;
+ for (int tries = 0; tries < 100'000; tries++) {
+ int n = Random::integer(3, 10);
+ auto ps = Random::convex(n, range);
+ ps.push_back(ps[0]);
+
+ for (int i = 0; i < 100; i++) {
+ pt a = Random::point<ll>(-range, range);
+ pt b = a;
+ while (b == a) b = Random::point<ll>(-range, range);
+
+ auto got = intersectLine(ps, a, b);
+
+ vector<int> expected;
+ for (int j = 0; j < n; j++) {
+ if (cross(ps[j], a, b) > 0 && cross(ps[j+1], a, b) < 0) expected.push_back(j);
+ if (cross(ps[j], a, b) < 0 && cross(ps[j+1], a, b) > 0) expected.push_back(j);
+ if (cross(ps[j], a, b) == 0) {
+ if (cross(ps[j+1], a, b) != 0 ||
+ cross(ps[(j+n-1) % n], a, b) != 0) {
+ expected.push_back(j);
+ }
+ }
+ }
+ if (sz(expected) > 1 && expected[0] == expected[1]) expected.pop_back();
+
+ sort(all(got));
+ sort(all(expected));
+
+ if (got != expected) cerr << "error" << FAIL;
+
+ queries += n;
+ }
+ }
+ cerr << "tested intersect: " << queries << endl;
+}
+
+int main() {
+ test_area(100);
+ test_area(1'000'000'000);
+ test_windingNumber(100);
+ test_windingNumber(1'000'000'000);
+ test_inside(100);
+ test_inside(1'000'000'000);
+ test_insideConvex(100);
+ test_insideConvex(1'000'000'000);
+ test_minkowski(100);
+ test_minkowski(500'000'000);
+ test_dist(100);
+ test_dist(1'000'000'000);
+ test_extremal(100);
+ test_extremal(1'000'000'000);
+ test_intersect(100);
+ test_intersect(1'000'000'000);
+}