toytracer/material.cpp

#include "material.h"

bool Lambertian::scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const {
  //Vec3 scatter_direction = rec.normal + random_in_unit_sphere();
  Vec3 scatter_direction = rec.normal + random_unit_vector();
  //Vec3 scatter_direction = random_in_hemisphere(rec.normal);
  scattered = Ray(rec.p, scatter_direction);
  attenuation = albedo;
  return true;
}

bool Metal::scatter(const Ray& r_in, const hit_record& rec, Color& attenuation, Ray& scattered) const {
  Vec3 reflected = reflect(unit_vector(r_in.direction()), rec.normal);
  scattered = Ray(rec.p, reflected + fuzz * random_in_unit_sphere());
  attenuation = albedo;
  return (dot(scattered.direction(), rec.normal) > 0);
}