diff options
Diffstat (limited to 'geometry/circle.cpp')
| -rw-r--r-- | geometry/circle.cpp | 33 |
1 files changed, 0 insertions, 33 deletions
diff --git a/geometry/circle.cpp b/geometry/circle.cpp deleted file mode 100644 index 8ebc800..0000000 --- a/geometry/circle.cpp +++ /dev/null @@ -1,33 +0,0 @@ -// berechnet die Schnittpunkte von zwei kreisen -// (Kreise dürfen nicht gleich sein!) -vector<pt> circleIntersection(pt c1, double r1, - pt c2, double r2) { - double d = abs(c1 - c2); - if (d < abs(r1 - r2) || d > abs(r1 + r2)) return {}; - double a = (r1 * r1 - r2 * r2 + d * d) / (2 * d); - pt p = (c2 - c1) * a / d + c1; - if (d == abs(r1 - r2) || d == abs(r1 + r2)) return {p}; - double h = sqrt(r1 * r1 - a * a); - return {p + pt{0, 1} * (c2 - c1) * h / d, - p - pt{0, 1} * (c2 - c1) * h / d}; -} - -// berechnet die Schnittpunkte zwischen -// einem Kreis(Kugel) und einer Grade 2d und 3d -vector<pt> circleRayIntersection(pt center, double r, - pt orig, pt dir) { - vector<pt> result; - double a = dot(dir, dir); - double b = 2 * dot(dir, orig - center); - double c = dot(orig - center, orig - center) - r * r; - double discr = b * b - 4 * a * c; - if (discr >= 0) { - //t in [0, 1] => schnitt mit segment [orig, orig + dir] - double t1 = -(b + sqrt(discr)) / (2 * a); - double t2 = -(b - sqrt(discr)) / (2 * a); - if (t1 >= 0) result.push_back(t1 * dir + orig); - if (t2 >= 0 && abs(t1 - t2) > EPS) { - result.push_back(t2 * dir + orig); - }} - return result; -} |