vector.h

#pragma once
 
#include <cmath>
#include <iostream>
 
#include "software/geom/angle.h"
 
class Vector final
{
   public:
    explicit Vector();
 
    static Vector createFromAngle(const Angle &angle);
 
    Vector(double x, double y);
 
    Vector(const Vector &v);
 
    double x() const;
 
    double y() const;
 
    void set(double x, double y);
 
    void setX(double x);
 
    void setY(double y);
 
    double lengthSquared() const;
 
    double length() const;
 
    Vector normalize() const;
 
    Vector normalize(double length) const;
 
    Vector perpendicular() const;
 
    Vector rotate(const Angle &rot) const;
 
    Vector project(const Vector &other) const;
 
    double dot(const Vector &other) const;
 
    double cross(const Vector &other) const;
 
    double determinant(const Vector &other) const;
 
    Angle orientation() const;
 
    Vector &operator=(const Vector &other);
 
    bool isClockwiseOf(const Vector &other) const;
 
    bool isCounterClockwiseOf(const Vector &other) const;
 
   private:
    double x_;
 
    double y_;
};
 
Vector operator+(const Vector &p, const Vector &q) __attribute__((warn_unused_result));
 
Vector &operator+=(Vector &u, const Vector &v);
 
Vector operator-(const Vector &p) __attribute__((warn_unused_result));
 
Vector operator-(const Vector &u, const Vector &v) __attribute__((warn_unused_result));
 
Vector &operator-=(Vector &u, const Vector &v);
 
Vector operator*(double s, const Vector &v) __attribute__((warn_unused_result));
 
Vector operator*(const Vector &p, double s) __attribute__((warn_unused_result));
 
Vector &operator*=(Vector &p, double s);
 
Vector operator/(const Vector &p, double s) __attribute__((warn_unused_result));
 
Vector &operator/=(Vector &p, double s);
 
std::ostream &operator<<(std::ostream &os, const Vector &v);
 
bool operator==(const Vector &u, const Vector &v);
 
bool operator!=(const Vector &u, const Vector &v);
 
// We need to define a hash function so that the Vector class can be used in unordered STL
// containers
// like unordered_set and unordered_map
// https://prateekvjoshi.com/2014/06/05/using-hash-function-in-c-for-user-defined-classes/
namespace std
{
    template <>
    struct hash<Vector> final
    {
        size_t operator()(const Vector &v) const
        {
            hash<double> h;
            return h(v.x()) * 17 + h(v.y());
        }
    };
}  // namespace std