diff options
| -rw-r--r-- | content/geometry/lines.cpp | 16 | ||||
| -rw-r--r-- | content/geometry/linesAndSegments.cpp | 2 | ||||
| -rw-r--r-- | tcr.pdf | bin | 691160 -> 691136 bytes | |||
| -rw-r--r-- | test/geometry/lines.cpp | 107 | ||||
| -rw-r--r-- | test/geometry/linesAndSegments.cpp | 2 |
5 files changed, 117 insertions, 10 deletions
diff --git a/content/geometry/lines.cpp b/content/geometry/lines.cpp index 95536a4..36de1db 100644 --- a/content/geometry/lines.cpp +++ b/content/geometry/lines.cpp @@ -1,10 +1,10 @@ struct line { - double a, b, c; // ax + by + c = 0; vertikale Line: b = 0, sonst: b = 1 - line(pt p, pt q) : a(-imag(q-p)), b(real(q-p)), c(cross({b, -a},p)) {} + double a, b, c; // ax + by + c = 0; vertikale Gerade: b = 0 + line(pt p, pt q) : a(imag(p-q)), b(real(q-p)), c(cross({-b, a}, p)) {} }; -line pointsToLine(pt p1, pt p2) { - line l; +line pointsToLine(pt p1, pt p2) { // vertikale Gerade: b = 1 oder b = 0 + line l(0, 0); if (abs(real(p1 - p2)) < EPS) { l.a = 1; l.b = 0.0; l.c = -real(p1); } else { @@ -15,19 +15,19 @@ line pointsToLine(pt p1, pt p2) { return l; } -bool parallel(line l1, line l2) { +bool parallel(line l1, line l2) { // braucht b in {0, 1} return (abs(l1.a - l2.a) < EPS) && (abs(l1.b - l2.b) < EPS); } -bool same(line l1, line l2) { +bool same(line l1, line l2) { // braucht b in {0, 1} return parallel(l1, l2) && (abs(l1.c - l2.c) < EPS); } -bool intersect(line l1, line l2, pt& p) { +bool intersect(line l1, line l2, pt& res) { // braucht b in {0, 1} if (parallel(l1, l2)) return false; double y, x = (l2.b * l1.c - l1.b * l2.c) / (l2.a * l1.b - l1.a * l2.b); if (abs(l1.b) > EPS) y = -(l1.a * x + l1.c); else y = -(l2.a * x + l2.c); - p = {x, y}; + res = {x, y}; return true; } diff --git a/content/geometry/linesAndSegments.cpp b/content/geometry/linesAndSegments.cpp index 1e21cba..ddab554 100644 --- a/content/geometry/linesAndSegments.cpp +++ b/content/geometry/linesAndSegments.cpp @@ -5,7 +5,7 @@ bool pointOnLine(pt a, pt b, pt p) { // Test auf Linienschnitt zwischen a-b und c-d. (nicht identisch) bool lineIntersection(pt a, pt b, pt c, pt d) { - return abs(cross(a - b, c - d)) < EPS; + return abs(cross(a - b, c - d)) > EPS; } // Berechnet den Schnittpunkt der Graden a-b und c-d. Binary files differdiff --git a/test/geometry/lines.cpp b/test/geometry/lines.cpp new file mode 100644 index 0000000..7b1b99a --- /dev/null +++ b/test/geometry/lines.cpp @@ -0,0 +1,107 @@ +#include "../util.h" +constexpr double EPS = 1e-6; +#define ll double +double gcd(double x, double /**/) {return x;} //hacky +#include <geometry/formulas.cpp> +#undef ll +#include <geometry/linesAndSegments.cpp> +#include <geometry/lines.cpp> + +#include "../geometry.h" + +void stress_pointsToLine(ll range) { + ll queries = 0; + for (int tries = 0; tries < 100'000; tries++) { + auto [a, b] = Random::line(range); + + line gotA(a, b); + if (real(a) != real(b)) { + gotA.a /= gotA.b; + gotA.c /= gotA.b; + gotA.b /= gotA.b; + } else { + gotA.c /= gotA.a; + gotA.a /= gotA.a; + } + line gotB = pointsToLine(a, b); + + if (!same(gotA, gotB)) cerr << "error" << FAIL; + queries++; + } + cerr << "tested pointsToLine: " << queries << endl; +} + +void stress_same(ll range) { + ll queries = 0; + for (int tries = 0; tries < 100'000; tries++) { + auto [a, b] = Random::line(range); + auto [c, d] = Random::line(range); + + line lAB = pointsToLine(a, b); + line lCD = pointsToLine(c, d); + + auto got = same(lAB, lCD); + auto expected = pointOnLine(a, b, c) && pointOnLine(a, b, d); + + if (got != expected) cerr << "error" << FAIL; + queries++; + } + cerr << "tested same: " << queries << endl; +} + +void stress_parallel(ll range) { + ll queries = 0; + for (int tries = 0; tries < 100'000; tries++) { + auto [a, b] = Random::line(range); + auto [c, d] = Random::line(range); + + line lAB = pointsToLine(a, b); + line lCD = pointsToLine(c, d); + + auto got = parallel(lAB, lCD); + auto expected = cross(b-a, d-c) == 0; + + if (got != expected) cerr << "error" << FAIL; + queries++; + } + cerr << "tested parallel: " << queries << endl; +} + +void stress_intersect(ll range) { + ll queries = 0; + for (int tries = 0; tries < 100'000; tries++) { + auto [a, b] = Random::line(range); + auto [c, d] = Random::line(range); + + line lAB = pointsToLine(a, b); + line lCD = pointsToLine(c, d); + + if (same(lAB, lCD)) continue; + + pt gotPT; + auto got = intersect(lAB, lCD, gotPT); + auto expected = lineIntersection(a, b, c, d); + + if (got != expected) cerr << "error: 1" << FAIL; + if (got) { + pt expectedPt = lineIntersection2(a, b, c, d); + if (float_error(real(gotPT), real(expectedPt)) > 1e-6) cerr << "error: 2" << FAIL; + if (float_error(imag(gotPT), imag(expectedPt)) > 1e-6) cerr << "error: 2" << FAIL; + } + queries++; + } + cerr << "tested intersect: " << queries << endl; +} + +int main() { + stress_pointsToLine(100); + stress_pointsToLine(100'000); + stress_same(10); + stress_same(100); + stress_same(1'000'000'000);//no precision issue since this will alwas be false... + stress_parallel(10); + stress_parallel(100); + stress_parallel(1'000'000'000); + stress_intersect(100); + stress_intersect(1'000'000'000); +} diff --git a/test/geometry/linesAndSegments.cpp b/test/geometry/linesAndSegments.cpp index 233546b..a2da3ba 100644 --- a/test/geometry/linesAndSegments.cpp +++ b/test/geometry/linesAndSegments.cpp @@ -30,7 +30,7 @@ void stress_lineIntersection(ll range) { auto [c, d] = Random::line(range); if (ccw(a, b, c) == 0 && ccw(a, b, d) == 0) continue; - bool expected = ccw(0, a-b, c-d) == 0; + bool expected = ccw(0, a-b, c-d) != 0; bool got = lineIntersection(a, b, c, d); if (got != expected) cerr << "error" << FAIL; |