/******************************************************************/
/* This file is part of the homework assignments for CSCI-427/527 */
/* at The College of William & Mary and authored by Pieter Peers. */
/* No part of this file, whether altered or in original form, can */
/* be distributed or used outside the context of CSCI-427/527     */
/* without consent of either the College of William & Mary or     */
/* Pieter Peers.                                                  */
/******************************************************************/

#include "ray.h"

//////////////////
// Constructors //
//////////////////
ray::ray(const vec3d& origin, const vec3d& direction)
{
  _origin = origin;
  _direction = normalize(direction);
}

ray::ray(const ray& r)
{
  _origin = r._origin;
  _direction = r._direction;
}


///////////////
// Operators //
///////////////
ray& ray::operator=(const ray& r)
{
  _assign(r);
  return *this;
}


vec3d ray::operator()(float t) const
{
  return _origin + t*_direction;
}


float ray::operator()(const vec3d& point) const
{
  return _direction.dot(point - _origin);
}


//////////////
// Mutators //
//////////////
ray& ray::transform(const transformation3d& t)
{
  _origin = t.transformPoint(_origin);
  _direction = t.transformDirection(_direction);
  return *this;
}


ray& ray::inverseTransform(const transformation3d& t)
{
  _origin = t.inverseTransformPoint(_origin);
  _direction = t.inverseTransformDirection(_direction);
  return *this;
}


/////////////////////
// Private Methods //
/////////////////////
void ray::_swap(ray& r)
{
  swap(_origin, r._origin);
  swap(_direction, r._direction);
}


void ray::_assign(const ray& r)
{
  _origin = r._origin;
  _direction = r._direction;
}