diff options
Diffstat (limited to 'geometry')
| -rw-r--r-- | geometry/formulars.cpp | 6 | ||||
| -rw-r--r-- | geometry/linesAndSegments.cpp | 4 | ||||
| -rw-r--r-- | geometry/polygon.cpp | 4 |
3 files changed, 7 insertions, 7 deletions
diff --git a/geometry/formulars.cpp b/geometry/formulars.cpp index 855ef1e..37cc4f4 100644 --- a/geometry/formulars.cpp +++ b/geometry/formulars.cpp @@ -21,9 +21,9 @@ double norm(pt a) {return dot(a, a);} double cross(pt a, pt b) {return imag(conj(a) * b);} double cross(pt p, pt a, pt b) {return cross(a - p, b - p);} -// -1 => gegen den Uhrzeigersinn -// 0 => kolliniear -// 1 => im Uhrzeigersinn. +// 1 => c links von a->b +// 0 => a, b und c kolliniear +// -1 => c rechts von a->b int orientation(pt a, pt b, pt c) { double orien = cross(b - a, c - a); return (orien > EPS) - (orien < -EPS); diff --git a/geometry/linesAndSegments.cpp b/geometry/linesAndSegments.cpp index 3a8ac02..4da35b1 100644 --- a/geometry/linesAndSegments.cpp +++ b/geometry/linesAndSegments.cpp @@ -39,7 +39,7 @@ double distToLine(pt a, pt b, pt p) { // Liegt p auf der Geraden a-b? 2d und 3d bool pointOnLine(pt a, pt b, pt p) { - return orientation(a, b, p) == 0; + return cross(a, b, p) == 0; } // Test auf Linienschnitt zwischen a-b und c-d. @@ -57,7 +57,7 @@ pt lineIntersection(pt p0, pt p1, pt p2, pt p3) { // Liegt p auf der Strecke a-b? bool pointOnLineSegment(pt a, pt b, pt p) { - if (orientation(a, b, p) != 0) return false; + if (cross(a, b, p) != 0) return false; ld dist = norm(a - b); return norm(a - p) <= dist && norm(b - p) <= dist; } diff --git a/geometry/polygon.cpp b/geometry/polygon.cpp index 23420a1..1620d7c 100644 --- a/geometry/polygon.cpp +++ b/geometry/polygon.cpp @@ -24,7 +24,7 @@ ll windingNumber(pt p, const vector<pt>& poly) { } // Testet, ob ein Punkt im Polygon liegt (beliebige Polygone). -// Ändere Zeile 31 falls rand zählt, poly[0] == poly.back() +// Ändere Zeile 32 falls rand zählt, poly[0] == poly.back() bool inside(pt p, const vector<pt>& poly) { bool in = false; for (int i = 0; i + 1 < sz(poly); i++) { @@ -39,7 +39,7 @@ bool inside(pt p, const vector<pt>& poly) { } // convex hull without duplicates, h[0] == h.back() -// Change line 43 and 49 >= if border counts as inside +// Change line 45 and 51 >= if border counts as inside bool inside(pt p, const vector<pt>& hull) { int l = 0, r = sz(hull) - 1; if (cross(hull[0], hull[r], p) > 0) return false; |