/****************************************************************************
* VCGLib                                                            o o     *
* Visual and Computer Graphics Library                            o     o   *
*                                                                _   O  _   *
* Copyright(C) 2004                                                \/)\/    *
* Visual Computing Lab                                            /\/|      *
* ISTI - Italian National Research Council                           |      *
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* All rights reserved.                                                      *
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* 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      *
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* (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 (http://www.gnu.org/licenses/gpl.txt)          *
* for more details.                                                         *
*                                                                           *
****************************************************************************/
/****************************************************************************
  History

$Log: not supported by cvs2svn $
Revision 1.3  2004/04/26 09:38:54  pietroni
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Revision 1.2  2004/04/20 12:42:37  pietroni
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Revision 1.1  2004/04/15 08:54:20  pietroni
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****************************************************************************/

#ifndef TETRA_TYPE 
#pragma message("\nYou should never directly include this file\_n")
#else
#define NULL 0
#include<vcg/space/point3.h>
#include<vcg/space/tetra3.h>

namespace vcg {
/**
    \ingroup tetrahedron
    @name Tetrahedron
    Class Tetrahedron.
    This is the base class for definition of a Tetrahedron of the mesh.
	@param VTYPE (Template Parameter) Specifies the type for the vertex.
 */

template < class VTYPE >
class TETRA_TYPE{

public:

  ///	The base type of the face
	typedef TETRA_TYPE BaseTetraType;
	/// The vertex type 
	typedef typename VTYPE VertexType;
  /// The coordinate type used to represent the point (i.e. Point3f, Point3d, ...)
  typedef typename VertexType::CoordType CoordType;
  /// The scalar type used to represent coords (i.e. float, double, ...)
	typedef typename VertexType::ScalarType ScalarType;

 
/***********************************************/
/** @name Tetrahedron Flags
For each Tetrahedron we store a set of boolean values packed in a int. 
The default value for each flag is 0. Most commonly used flags are the \a deleted and the \a selected ones. 
Users can ask and dispose for a bit for their own purposes with the  vcg::TetrahedronFull::NewUserBit() and vcg::TetrahedronFull::DeleteUserBit() functions. 
The value returned by these functions has to be passed to the 
vcg::TetrahedronFull::SetUserBit() vcg::TetrahedronFull::ClearUserBit() and vcg::TetrahedronFull::IsUserBit() functions to check and modify the obtained bit flag.

**/
//@{

/// This are the flags of tetrahedron, the default value is 0
	int  _flags;
 
  enum {
	DELETED     = 0x00000001,	 // deleted tetrahedron flag
	SELECTED		= 0x00000002,	 // Selection flag
	BORDERF0    = 0x00000004,  // Border flag, Face 0
	BORDERF1    = 0x00000008,  // Border flag, Face 1
	BORDERF2    = 0x00000010,  // Border flag, Face 2
  BORDERF3    = 0x00000020,  // Border flag, Face 3
  BORDERE0    = 0x00000040,  // Border flag, Edge 0
	BORDERE1    = 0x00000080,  // Border flag, Edge 1
	BORDERE2    = 0x00000100,  // Border flag, Edge 2
  BORDERE3    = 0x00000200,  // Border flag, Edge 3
  BORDERE4    = 0x00000400,  // Border flag, Edge 4
  BORDERE5    = 0x00000800,  // Border flag, Edge 5
	USER0				= 0x00001000,  // new flag for user
	};

public:
  	/// Return the vector of _flags
	inline int & Flags ()
	{
			assert( (_flags & DELETED) == 0 );
			return _flags;
	}

static int &LastBitFlag()
		{
			static int b =USER0;
			return b;
		}
static inline int NewBitFlag()
		{
			LastBitFlag()=LastBitFlag()<<1;
			return LastBitFlag();
		}
static inline bool DeleteBitFlag(int bitval)
		{	
			if(LastBitFlag()==bitval) {
					LastBitFlag()= LastBitFlag()>>1;
					return true;
			}
			assert(0);
			return false;
		}

/// This function checks if the given user bit is true.
bool IsUserBit(int userBit){return (_flags & userBit) != 0;}
/// This function set  the given user bit.
void SetUserBit(int userBit){_flags |=userBit;}
/// This function clear the given user bit.
void ClearUserBit(int userBit){_flags &= (~userBit);}
/// This function checks if the tetrahedron is deleted.
bool IsD() const {return (_flags & DELETED) != 0;}
/// This function mark the tetrahedron as deleted.
void SetD()		{_flags |=DELETED;}
/// This function mark the tetrahedron as not deleted.
void ClearD() {_flags &=~DELETED;}
/// This function mark the tetrahedron as selected.
void SetS() {_flags |=SELECTED;}
/// This function mark the tetrahedron as not selected.
void ClearS() {_flags &=~SELECTED;}
/// This function return true if one face is extern.
bool HaveBorderF() {return ((_flags & (BORDERF0 | BORDERF1 | BORDERF2 | BORDERF3)) != 0);}
/// This function return true if the face is extern.
bool IsBorderF(int face) {
  assert ((face<4)&&(face>-1));
  return (this->T(face) == this);
}
 //@}

/***********************************************/
/** @name Vertex Pointers
For each Tetrahedron we store 4 pointers to vertex
**/
//@{
 /// The 4 vertices of the tetrahedron
protected:
	VertexType *_v[4];
public:
 
/** Return the pointer to the j-th vertex of the terahedron.
		@param j Index of the tetrahedron's vertex.
	 */
	inline VertexType * & V( const int j )
	{	
		assert( (_flags & DELETED) == 0 );
		assert(j >= 0);
		assert(j <  4);
		return _v[j];
	}

	inline const VertexType * const & V( const int j ) const
	{
		assert( (_flags & DELETED) == 0 );
		assert(j>=0);
		assert(j<4);
		return _v[j];
	}
  
	inline const VertexType * const & cV( const int j ) const
	{
		assert( (_flags & DELETED) == 0 );
		assert(j>=0);
		assert(j<4);
		return _v[j];
	}

/***********************************************/
/** @name Topology Structures
For each Tetrahedron we store 2 array for Tatrahedron - Tetrahedron topology ( sharing Face)
and 2 array to implement the list of Vertex - Tetrahedron Topology (List of Tetrahedron sharing a vertex).
**/
//@{


#ifdef __VCGLIB_TETRA_A
protected:
  ///pointers to tetrahedron for tetrahedron-tetrahedron topology (sharing same face)
	TETRA_TYPE *_t[4];
  ///index of face for tetrahedron-tetrahedron topology (sharing same face)
	int _z[4]; 
public:
  ///Function to access the Tetrahedron that share the index-face (extern face returns a pointer to himself)
  	TETRA_TYPE *&T(const int &index)
	{
		return _t[index];
	}
  ///Function to see the index of the face as seen from the other tetrahedron (extern face returns -1)
	int &Z(const int &index)
	{
		return _z[index];
	}
#endif 

#ifdef __VCGLIB_TETRA_V
protected:
	///pointers to tetrahedron for vertex-tetrahedron topology (sharing same vertex)
	TETRA_TYPE *_tv[4];
  ///index of vertex for vertex-tetrahedron topology (sharing same vertex)
	short int _zv[4];
public:
  ///Function to access the Next Tetrahedron of the list that share the index-face (end of list is Null)
  	TETRA_TYPE *&TV(const int &index)
	{
		return _tv[index];
	}
  ///Function to see the index of the Vertex as seen from the next tetrahedron of the list ( end of list is -1)
	short int &ZV(const int &index)
	{
		return _zv[index];
	}
#endif
//@}

/***********************************************/
/** @Default Tatrahedron Functions**/
//@{
public:

  ///Constructor
	TETRA_TYPE()
	{	
		_flags=0;
	}
  ///initialize default parameters of tetrahedron
	virtual 	void Init(VertexType * p0,VertexType * p1,VertexType * p2,VertexType * p3)
				{
					_flags = 0;
					_v[0]=p0;
					_v[1]=p1;
					_v[2]=p2;
					_v[3]=p3;

					if(ComputeVolume()<0 )
						swap(_v[1],_v[2]);

#ifdef		__VCGLIB_TETRA_A
					_z[0]=_z[1]=_z[2]=_z[3]=-1;
					_t[0]=_t[1]=_t[2]=_t[3]=NULL;
#endif
#ifdef		__VCGLIB_TETRA_V
					_zv[0]=_zv[1]=_zv[2]=_zv[3]=-1;
					_tv[0]=_tv[1]=_tv[2]=_tv[3]=NULL;
#endif					
			}
 ///set border vertices using TT-topology
#ifdef __VCGLIB_TETRA_A
	void setBorderV()
	{	
		int i;
		for (i=0;i<4;i++)
			if (T(i)==this)
			{
				FV(i,0)->SetB();
				FV(i,1)->SetB();
				FV(i,2)->SetB();
			}
	}
#endif
//@}

/***********************************************/
/** @Generic geometric and quality funtions of a tetrahedron**/
//@{

#ifdef __VCGLIB_TETRA_Q
		ScalarType _volume;	
		ScalarType _aspect_ratio; 
#endif


 	ScalarType ComputeVolume(){
      Tetra3<ScalarType> T(V(0)->cP(),V(1)->cP(),V(2)->cP(),V(3)->cP());
      #ifdef __VCGLIB_TETRA_Q
			_volume = T.ComputeVolume();
      return _volume;
      #else
       return (T.ComputeVolume());
      #endif
		}


	///return the volume of the tetrahedron
	const double & Volume(){
#ifdef __VCGLIB_TETRA_Q
		return _volume;
#else
		return (( V(2)->cP()-V(0)->cP())^(V(1)->cP()-V(0)->cP() ))*(V(3)->cP()-V(0)->cP())/6.0;
#endif
		}	
  ///return aspect ratio of the tetrahedron
	double AspectRatio(){
#ifdef __VCGLIB_TETRA_Q
		return _aspect_ratio;
#else
		return ComputeAspectRatio();
#endif
		}
//@}


};//end class

}//end namespace
#endif