1
0
raytracing-in-a-weekend-oop/vec3.h

103 lines
2.1 KiB
C++

#ifndef VEC3_H
#define VEC3_H
#include <cmath>
#include <iostream>
using std::sqrt;
class vec3 {
public:
vec3() : e{0, 0, 0} {}
vec3(double e0, double e1, double e2) : e{e0, e1, e2} {}
double x() const { return e[0]; }
double y() const { return e[1]; }
double z() const { return e[2]; }
vec3 operator-() const { return vec3(-e[0], -e[1], -e[2]); }
double operator[](int i) const { return e[i]; }
double& operator[](int i) { return e[i]; }
vec3& operator+=(const vec3 &v) {
e[0] += v.e[0];
e[1] += v.e[1];
e[2] += v.e[2];
return *this;
}
vec3& operator*=(const double t) {
e[0] *= t;
e[1] *= t;
e[2] *= t;
return *this;
}
vec3& operator/=(const double t) {
return *this *= 1/t;
}
double length() {
return sqrt(length_squared());
}
double length_squared() {
return e[0]*e[0] + e[1]*e[1] + e[2]*e[2];
}
public:
double e[3];
};
// Type aliases for vec3
using point3 = vec3; // 3D point
using color = vec3; // RGB color
// vec3 utility functions
inline std::ostream& operator<<(std::ostream& out, const vec3 &v) {
return out<<v.e[0]<<" "<<v.e[1]<<" "<<v.e[2];
}
inline vec3 operator+(const vec3 &u, const vec3 &v) {
return vec3(u.e[0] + v.e[0], u.e[1] + v.e[1], u.e[2] + v.e[2]);
}
inline vec3 operator-(const vec3 &u, const vec3 &v) {
return vec3(u.e[0] - v.e[0], u.e[1] - v.e[1], u.e[2] - v.e[2]);
}
inline vec3 operator*(const vec3 &u, const vec3 &v) {
return vec3(u.e[0] * v.e[0], u.e[1] * v.e[1], u.e[2] * v.e[2]);
}
inline vec3 operator*(double t, const vec3 &v) {
return vec3(t * v.e[0], t * v.e[1], t * v.e[2]);
}
inline vec3 operator*(const vec3 &v, double t) {
return t * v;
}
inline vec3 operator/(const vec3 &v, double t) {
return (1/t) * v;
}
inline double dot(const vec3 &u, const vec3 &v) {
return u.e[0] * v.e[0]
+ u.e[1] * v.e[1]
+ u.e[2] * v.e[2];
}
inline vec3 cross(const vec3 &u, const vec3 &v) {
return vec3(u.e[1] * v.e[2] - u.e[2] * v.e[1],
u.e[2] * v.e[0] - u.e[0] * v.e[2],
u.e[0] * v.e[1] - u.e[1] * v.e[0]);
}
inline vec3 unit_vector(vec3 v) {
return v / v.length();
}
#endif