//
// ============================================================
//
//                      Light
//
// ============================================================
//
//
//      Copyright (C) 1997
//
//                      Professor Kenneth I. Joy
//                      Computer Science Department
//                      University of California
//                      Davis, CA  95616
//
//      Permission is granted to use at your own risk and 
//      distribute this software in source and binary forms 
//      provided the above copyright notice and this paragraph 
//      are preserved on all copies.  This software is provided 
//      "as is" with no express or implied warranty.
//
//
//  ============================================================
//

#include <stdlib.h>
#include <math.h>
#include <strings.h>
#include <stream.h>
#include <GL/gl.h>
#include "Light.h"

#define		TRUE		1 
#define		FALSE		0


/*
   ==========================================================

	       CONSTRUCTORS, DESTRUCTOR

   ==========================================================
*/

Light :: Light () {}

Light :: Light ( const Point& location, const Color& diffuse )

   {
      _position = location ;
      _diffuse = diffuse ;
   }

Light :: Light ( const Light& c ) 

   {
      _position = c._position ;
      _diffuse = c._diffuse ;
   }

Light :: ~Light () { }
      

/*
   ==========================================================

	       OPERATOR=

   ==========================================================
*/

Light& Light :: operator= ( const Light& c ) 

   {
      if ( this == &c ) return ( *this ) ;

      _position = c._position ;
      _diffuse = c._diffuse ;

      return ( *this ) ;
   }

/*
   ==========================================================

	       OUTPUT

   ==========================================================
*/

ostream& operator<< ( ostream& co, const Light& c )

   {
      return c.output( co ) ;
   }

/*
   ==========================================================

	       OUTPUT

   ==========================================================
*/

ostream& Light :: output ( ostream& co ) const

   {
      co << "Light ( " 
	 << _position << ", " 
	 << _diffuse << " )" << endl ;

      return ( co ) ;
   }


/*
   ==========================================================

	       GL Setup Stuff

   ==========================================================
*/

void Light :: GL () const

   {
      GLfloat array[4] ;

      array[0] = 0.0 ;
      array[1] = 0.0 ;
      array[2] = 0.0 ;
      array[3] = 1.0 ;

      glLightfv ( GL_LIGHT0, GL_AMBIENT, array ) ;

      array[0] = GLfloat ( _position.x() ) ;
      array[1] = GLfloat ( _position.y() ) ;
      array[2] = GLfloat ( _position.z() ) ;
      array[3] = 1.0 ;

      glLightfv ( GL_LIGHT0, GL_POSITION, array ) ;

      array[0] = GLfloat ( _diffuse.red() ) ;
      array[1] = GLfloat ( _diffuse.green() ) ;
      array[2] = GLfloat ( _diffuse.blue() ) ;
      array[3] = 1.0 ;

      glLightfv ( GL_LIGHT0, GL_DIFFUSE, array ) ;

      //array[0] = 1.0 ;
      //array[1] = 1.0 ;
      //array[2] = 1.0 ;
      //array[3] = 1.0 ;

      glLightfv ( GL_LIGHT0, GL_SPECULAR, array ) ;
   }