message: Don't alter ray dir
diff: @@ -101,9 +101,6 @@ inline void setRay(Ray &ray, const vec3f &ray_org, const vec3f &ray_dir,
  {
  ray.org = ray_org;
  ray.dir = ray_dir;
  - if (ray.dir.x == 0.f) ray.dir.x = 1e-6f;
  - if (ray.dir.y == 0.f) ray.dir.y = 1e-6f;
  - if (ray.dir.z == 0.f) ray.dir.z = 1e-6f;
  ray.t0 = t0;
  ray.t = t1;
  ray.time = time;
  