diff options
Diffstat (limited to 'content')
| -rw-r--r-- | content/geometry/lines.cpp | 16 | ||||
| -rw-r--r-- | content/geometry/linesAndSegments.cpp | 2 |
2 files changed, 9 insertions, 9 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. |