/*
Danger from the Deep - Open source submarine simulation
Copyright (C) 2003-2006  Thorsten Jordan, Luis Barrancos and others.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#ifndef DAYSKY_H
#define DAYSKY_H

#include "color.h"
#include "tone_reproductor.h"

class daysky {
 public:
	//! Constructor.
	daysky();
	daysky(float azimuth, float elevation, float turbidity);
	//! Set turbidity.
	void set_turbidity( float pT );
	//! Get turbidity.
	inline float get_turbidity() const { return m_T; }
	//! Set sun position.
	void set_sun_position( float azimuth, float elevation );
	//! Get color.
	colorf get_color( float theta, float phi, float elevation ) const;

 private:
	struct alphabet {
		float A, B, C, D, E;
	};
	  
	//! Calculate distribution
	inline float distribution( const alphabet &ABCDE, float Theta, float Gamma ) const;
	//! Calc the actual color/chromaticity
	inline float chromaticity( const float ZC[3][4] ) const;

	inline void recalculate_chroma();
	inline void recalculate_alphabet();

	float m_T, m_T2;    // Turbidity T and T^2
	float m_sun_theta;
	float m_sun_phi, m_sun_phi2, m_sun_phi3;
	float m_chroma_xZC, m_chroma_yZC;
	alphabet m_luminance, m_x, m_y;

	mutable tone_reproductor tonerepro;
};  //DaySky

// class DaySky is used to create the colormap used for sky in dd

#endif