/******************************************************************/
/* 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 "constants.h"
#include "directionalLightsource.h"

//////////////////
// Constructors //
//////////////////
directionalLightsource::directionalLightsource(const vec3d& direction, const color& power)
{
  _direction = normalize(direction);
  _power = power;
}


/////////////
// Methods //
/////////////
lightSample directionalLightsource::intensityAt(const vec3d& point) const
{
  return lightSample(_direction, _power, +LARGE);
}


lightSample directionalLightsource::emittanceAt(const vec3d& point, float r1, float r2) const
{
  // Set emittance to _power * distance^2 to compensate for squared distance fall off.
  // Distance is set to large (to ensure everything can occlude).
  // Foreshortening == 1
  // PDF == 1 (no selection).
  return lightSample(_direction, _power * LARGE * LARGE, LARGE, 1.0f, 1.0f);
}

/////////////////////
// Private Methods //
/////////////////////
void directionalLightsource::_print(std::ostream& s) const
{
  s << "Directional Lightsource: direction=" << _direction << ", power=" << _power;  
}