//
//  glgrav - OpenGL N-Body gravity simulator
//
//  Copyright (C) 2003  Ian Cowburn (ianc@noddybox.demon.co.uk)
//
//  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
//
//  -------------------------------------------------------------------------
//
//  Mass
//
// $Id$
//
#ifndef MASS_H

#define MASS_H

#include "global.h"

class Mass
    {
    public:
	enum DrawItem {eMass, eRing};

	Mass();
    	Mass(const string& name, double mass, double scale,
	     double posx, double posy, double posz,
	     double dx, double dy, double dz,
	     GLfloat r, GLfloat g, GLfloat b,
	     double rot, int sheild=0);
	virtual ~Mass();

	// Define a ring
	//
	void setRing(double from, double to, 
		     GLfloat r, GLfloat g, GLfloat b, GLfloat alpha,
		     double rot, double angle);

	// Set up an Open GL texture ID to use.  It is assumed that
	// texturing is not used till this member is called.
	//
	// The get function returns true if a texture has been assigned.
	//
	void setTexture(GLuint id);
	bool getTexture(GLuint& id) const;

	void setRingTexture(GLuint id);
	bool getRingTexture(GLuint& id) const;

	// Get Mass information
	//
	string getName() const;
	double getMass() const;
	double getSize() const;
	void getPosition(double& x, double& y, double& z) const;
	void getPreviousPosition(double& x, double& y, double& z) const;
	void getDelta(double& dx, double& dy, double& dz) const;
	void getColour(GLfloat& r, GLfloat& g, GLfloat& b) const;

	bool isMassless() const;

	// All resetting of various controls for collisions
	//
	void reset(double mass, double dx, double dy, double dz);
	void reset(double mass);

	// Attract the object to the provided mass.  Note that the supplied
	// mass is left unaltered.
	//
	// Returns true if the two objects have collided
	//
	bool calcAttraction(Mass& m, double gr_const);

	// Move the mass along it's delta
	//
	void move();

	void draw(bool solid, bool texture, DrawItem item) const;

	// Streaming
	//
	friend ostream& operator<<(ostream& os, const Mass& m);

    private:
	string	m_name;
	double	m_size;
    	double	m_mass;
	double	m_scale;
	double	m_x,m_y,m_z;
	double	m_prevx,m_prevy,m_prevz;
	double	m_dx,m_dy,m_dz;
	GLfloat	m_r,m_g,m_b;

	bool	m_massless;

	double	m_rot;
	double	m_ang;

	int	m_shield;

	bool	m_textured;
	GLuint	m_texture_id;

	bool	m_ring;
	double	m_ring_from,m_ring_to;
	double	m_ring_rot,m_ring_ang,m_ring_tilt;
	GLfloat	m_rr,m_rg,m_rb;
	GLfloat	m_ring_alpha;
	bool	m_ring_textured;
	GLuint	m_ring_id;

	double	calcDistance2(Mass& m, double& dx, double& dy, double& dz);
	void	calcSize();
    };


// Routine to find masses from a vector of them
//
bool findMass(vector<Mass>& m, const string& name, Mass& ret);
bool findMass(vector<Mass>& m, const string& name,
	      vector<Mass>::size_type& index);


#endif

// END OF FILE //