text: #ifndef RAY_H
  #define RAY_H
  #include "vec3.h"
  class Ray {
    public:
      Vec3 origin;
      Vec3 direction;
      constexpr static float tmin = 0.005;
      mutable float tmax;
      mutable int hitCount;
  
      Ray() {
        hitCount = 0;
        tmax = 10000;
      };
      Ray(const Vec3& o, const Vec3& d) : origin(o), direction(d) {
        hitCount = 0;
        tmax = 10000;
      };
  
      Vec3 operator()(float t) const {
        return origin + t*direction;
      };
  };
  #endif
  