geometry/is_intersect_cp.hpp

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• Last update: 2024-04-27 01:27:28+09:00
• Include: #include "geometry/is_intersect_cp.hpp"

Depends on

• geometry/base.hpp
• geometry/circle.hpp
• geometry/point.hpp

Code

#include "base.hpp"
#include "circle.hpp"
#include "point.hpp"

namespace geometry {
bool is_intersect_cp(const Circle &c, const Point &p) {
  return equals(abs(p - c.p) - c.r, 0);
}
}  // namespace geometry

#line 2 "geometry/base.hpp"

namespace geometry {
using Real = double;
const Real EPS = 1e-8;
const Real PI = acos(static_cast<Real>(-1));

enum { OUT, ON, IN };

inline int sign(const Real &r) { return r <= -EPS ? -1 : r >= EPS ? 1 : 0; }

inline bool equals(const Real &a, const Real &b) { return sign(a - b) == 0; }
}  // namespace geometry
#line 3 "geometry/point.hpp"

namespace geometry {
using Point = complex<Real>;

istream &operator>>(istream &is, Point &p) {
  Real a, b;
  is >> a >> b;
  p = Point(a, b);
  return is;
}

ostream &operator<<(ostream &os, const Point &p) {
  return os << real(p) << " " << imag(p);
}

Point operator*(const Point &p, const Real &d) {
  return Point(real(p) * d, imag(p) * d);
}

// rotate point p counterclockwise by theta rad
Point rotate(Real theta, const Point &p) {
  return Point(cos(theta) * real(p) - sin(theta) * imag(p),
               sin(theta) * real(p) + cos(theta) * imag(p));
}

Real cross(const Point &a, const Point &b) {
  return real(a) * imag(b) - imag(a) * real(b);
}

Real dot(const Point &a, const Point &b) {
  return real(a) * real(b) + imag(a) * imag(b);
}

bool compare_x(const Point &a, const Point &b) {
  return equals(real(a), real(b)) ? imag(a) < imag(b) : real(a) < real(b);
}

bool compare_y(const Point &a, const Point &b) {
  return equals(imag(a), imag(b)) ? real(a) < real(b) : imag(a) < imag(b);
}

using Points = vector<Point>;
}  // namespace geometry
#line 3 "geometry/circle.hpp"

namespace geometry {
struct Circle {
  Point p;
  Real r{};

  Circle() = default;

  Circle(const Point &p, const Real &r) : p(p), r(r) {}
};

using Circles = vector<Circle>;
}  // namespace geometry
#line 4 "geometry/is_intersect_cp.hpp"

namespace geometry {
bool is_intersect_cp(const Circle &c, const Point &p) {
  return equals(abs(p - c.p) - c.r, 0);
}
}  // namespace geometry

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