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

$Log: not supported by cvs2svn $
Revision 1.18  2008/03/18 10:31:47  cignoni
added color interpolation to butterfly

Revision 1.17  2007/03/27 09:25:14  cignoni
corrected managment of selected flag when refining the whole mesh flipmesh

Revision 1.16  2007/03/12 15:37:18  tarini
Texture coord name change!  "TCoord" and "Texture" are BAD. "TexCoord" is GOOD.

Revision 1.15  2007/01/18 18:15:14  cignoni
added missing typenames

Revision 1.14  2007/01/17 14:31:47  giec
Added TrSplit function.

Revision 1.13  2006/10/27 13:26:49  ganovelli
changed   &*vert.end() to !vert.empty()  -> &vert.back() to comply vs2005 compiler

Revision 1.12  2006/06/18 20:42:01  cignoni
removed wrong fn setting

Revision 1.11  2006/06/06 14:35:28  zifnab1974
Changes for compilation on linux AMD64. Some remarks: Linux filenames are case-sensitive. _fileno and _filelength do not exist on linux

Revision 1.10  2006/05/03 21:42:10  cignoni
HasPerWedgeTexture -> HasPerWedgeTexture(m)

Revision 1.9  2005/12/22 11:24:09  cignoni
removed div by zero bug in callback of refine (tnx to Mario Latronico)

Revision 1.8  2005/12/13 11:01:01  cignoni
Added Callback in refine

Revision 1.7  2005/12/02 00:06:37  cignoni
commented out an old TRACE

Revision 1.6  2005/07/11 13:13:33  cignoni
small gcc-related compiling issues (typenames,ending cr, initialization order)

Revision 1.5  2005/06/29 15:25:41  callieri
deleted a wrong declaration "typename typename"

Revision 1.4  2005/06/17 00:48:27  cignoni
Corrected the type name of wedge tex coords WedgeInterp in RefineE

Revision 1.3  2005/02/25 10:28:04  pietroni
added #include<vcg/complex/trimesh/update/topology.h> use of update topology in refineE

Revision 1.2  2005/02/02 16:01:13  pietroni
1 warning corrected

Revision 1.1  2004/10/12 15:42:29  ganovelli
first working version


****************************************************************************/

#ifndef __VCGLIB_REFINE
#define __VCGLIB_REFINE

#include <functional>
#include <map>
#include <vector>
#include <vcg/space/sphere3.h>
#include <vcg/space/plane3.h>
#include <vcg/space/texcoord2.h>
#include <vcg/space/color4.h>
#include <vcg/simplex/face/pos.h>
#include<vcg/complex/trimesh/allocate.h>
#include<vcg/complex/trimesh/update/topology.h>
#include<wrap/callback.h>
#include <vcg/complex/trimesh/base.h>
#include <vcg/space/triangle3.h>

namespace vcg{

/* The table which encodes how to subdivide a triangle depending 
   on the splitted edges is organized as such:

    TriNum (the first number):    encodes the number of triangles
    TV (the following 4 triples): encodes the resulting triangles where
          0, 1, 2 are the original vertices of the triangles and 3, 4, 5 
          (mp01, mp12, mp20) are the midpoints of the three edges.

   In the case two edges are splitted the triangle has 2 possible splittings:
we need to choose a diagonal of the resulting trapezoid.
'swap' encodes the two diagonals to test: if diag1 < diag2 we swap the diagonal
like this (140, 504 -> 150, 514) (the second vertex of each triangles is replaced 
 by the first vertex of the other one).
            2
           / \
          5---4
         /     \
        0-------1

*/

class Split {
public:
	int TriNum;			// number of triangles
	int TV[4][3];   // The triangles coded as the following convention 
									//     0..2 vertici originali del triangolo 
									//     3..5 mp01, mp12, mp20 midpoints of the three edges
	int swap[2][2]; // the two diagonals to test for swapping
	int TE[4][3];   // the edge-edge correspondence between refined triangles and the old one
									//      (3) means the edge of the new triangle is internal;
};

const Split SplitTab[8]={
/* m20 m12 m01 */
/*  0   0   0 */	{1, {{0,1,2},{0,0,0},{0,0,0},{0,0,0}}, {{0,0},{0,0}},  {{0,1,2},{0,0,0},{0,0,0},{0,0,0}} },
/*  0   0   1 */	{2, {{0,3,2},{3,1,2},{0,0,0},{0,0,0}}, {{0,0},{0,0}},  {{0,3,2},{0,1,3},{0,0,0},{0,0,0}} },
/*  0   1   0 */	{2, {{0,1,4},{0,4,2},{0,0,0},{0,0,0}}, {{0,0},{0,0}},  {{0,1,3},{3,1,2},{0,0,0},{0,0,0}} },
/*  0   1   1 */	{3, {{3,1,4},{0,3,2},{4,2,3},{0,0,0}}, {{0,4},{3,2}},  {{0,1,3},{0,3,2},{1,3,3},{0,0,0}} },
/*  1   0   0 */	{2, {{0,1,5},{5,1,2},{0,0,0},{0,0,0}}, {{0,0},{0,0}},  {{0,3,2},{3,1,2},{0,0,0},{0,0,0}} },
/*  1   0   1 */	{3, {{0,3,5},{3,1,5},{2,5,1},{0,0,0}}, {{3,2},{5,1}},  {{0,3,2},{0,3,3},{2,3,1},{0,0,0}} },
/*  1   1   0 */	{3, {{2,5,4},{0,1,5},{4,5,1},{0,0,0}}, {{0,4},{5,1}},  {{2,3,1},{0,3,2},{3,3,1},{0,0,0}} },
/*  1   1   1 */	//{4, {{0,3,5},{3,1,4},{5,4,2},{3,4,5}}, {{0,0},{0,0}},  {{0,3,2},{0,1,3},{3,1,2},{3,3,3}} },
/*  1   1   1 */	{4, {{3,4,5},{0,3,5},{3,1,4},{5,4,2}}, {{0,0},{0,0}},  {{3,3,3},{0,3,2},{0,1,3},{3,1,2}} },
};

// Classe di suddivisione base. Taglia il lato esattamente a meta'.
template<class MESH_TYPE>
struct MidPoint : public   std::unary_function<face::Pos<typename MESH_TYPE::FaceType> ,  typename MESH_TYPE::CoordType >
{
	void operator()(typename MESH_TYPE::VertexType &nv, face::Pos<typename MESH_TYPE::FaceType>  ep){
		nv.P()=   (ep.f->V(ep.z)->P()+ep.f->V1(ep.z)->P())/2.0;

		if( MESH_TYPE::HasPerVertexNormal())
			nv.N()= (ep.f->V(ep.z)->N()+ep.f->V1(ep.z)->N()).Normalize();

		if( MESH_TYPE::HasPerVertexColor())
			nv.C().lerp(ep.f->V(ep.z)->C(),ep.f->V1(ep.z)->C(),.5f);
		
		if( MESH_TYPE::HasPerVertexQuality())
			nv.Q() = ((ep.f->V(ep.z)->Q()+ep.f->V1(ep.z)->Q())) / 2.0;
	}

	Color4<typename MESH_TYPE::ScalarType> WedgeInterp(Color4<typename MESH_TYPE::ScalarType> &c0, Color4<typename MESH_TYPE::ScalarType> &c1)
	{
		Color4<typename MESH_TYPE::ScalarType> cc;
		return cc.lerp(c0,c1,0.5f);
	}

	template<class FL_TYPE>
	TexCoord2<FL_TYPE,1> WedgeInterp(TexCoord2<FL_TYPE,1> &t0, TexCoord2<FL_TYPE,1> &t1)
	{
		TexCoord2<FL_TYPE,1> tmp;
		assert(t0.n()== t1.n());
		tmp.n()=t0.n(); 
		tmp.t()=(t0.t()+t1.t())/2.0;
		return tmp;
	}
};



template<class MESH_TYPE>
struct MidPointArc : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> ,  typename MESH_TYPE::CoordType>
{
	void operator()(typename MESH_TYPE::VertexType &nv, face::Pos<typename MESH_TYPE::FaceType> ep)
	{
		const typename MESH_TYPE::ScalarType EPS =1e-10;
		typename MESH_TYPE::CoordType vp = (ep.f->V(ep.z)->P()+ep.f->V1(ep.z)->P())/2.0;
		typename MESH_TYPE::CoordType  n = (ep.f->V(ep.z)->N()+ep.f->V1(ep.z)->N())/2.0;
		typename MESH_TYPE::ScalarType w =n.Norm();
		if(w<EPS) { nv.P()=(ep.f->V(ep.z)->P()+ep.f->V1(ep.z)->P())/2.0; return;}
		n/=w;
		typename MESH_TYPE::CoordType d0 = ep.f->V(ep.z)->P() - vp;
		typename MESH_TYPE::CoordType d1 = ep.f->V1(ep.z)->P()- vp;
		typename MESH_TYPE::ScalarType d=Distance(ep.f->V(ep.z)->P(),ep.f->V1(ep.z)->P())/2.0;

		typename MESH_TYPE::CoordType  nn = ep.f->V1(ep.z)->N() ^ ep.f->V(ep.z)->N();
		typename MESH_TYPE::CoordType  np = n ^ d0; //vector perpendicular to the edge plane, normal is interpolated
		np.Normalize();
		double sign=1;
		if(np*nn<0) sign=-1; // se le normali non divergono sposta il punto nella direzione opposta
    
		typename MESH_TYPE::CoordType n0=ep.f->V(ep.z)->N() -np*(ep.f->V(ep.z)->N()*np);
		n0.Normalize();
		typename MESH_TYPE::CoordType n1=ep.f->V1(ep.z)->N()-np*(ep.f->V1(ep.z)->N()*np);
		assert(n1.Norm()>EPS);
		n1.Normalize();
		typename MESH_TYPE::ScalarType cosa0=n0*n;
		typename MESH_TYPE::ScalarType cosa1=n1*n;
		if(2-cosa0-cosa1<EPS) {nv.P()=(ep.f->V(ep.z)->P()+ep.f->V1(ep.z)->P())/2.0;return;}
		typename MESH_TYPE::ScalarType cosb0=(d0*n)/d;
		typename MESH_TYPE::ScalarType cosb1=(d1*n)/d;
		assert(1+cosa0>EPS);
		assert(1+cosa1>EPS);
		typename MESH_TYPE::ScalarType delta0=d*(cosb0 +sqrt( ((1-cosb0*cosb0)*(1-cosa0))/(1+cosa0)) );
		typename MESH_TYPE::ScalarType delta1=d*(cosb1 +sqrt( ((1-cosb1*cosb1)*(1-cosa1))/(1+cosa1)) );
		assert(delta0+delta1<2*d);
		nv.P()=vp+n*sign*(delta0+delta1)/2.0;
		return ;
	}

	// Aggiunte in modo grezzo le due wedgeinterp
	Color4<typename MESH_TYPE::ScalarType> WedgeInterp(Color4<typename MESH_TYPE::ScalarType> &c0, Color4<typename MESH_TYPE::ScalarType> &c1)
	{
		Color4<typename MESH_TYPE::ScalarType> cc;
		return cc.lerp(c0,c1,0.5f);
	}

	template<class FL_TYPE>
	TexCoord2<FL_TYPE,1> WedgeInterp(TexCoord2<FL_TYPE,1> &t0, TexCoord2<FL_TYPE,1> &t1)
	{
		TexCoord2<FL_TYPE,1> tmp;
		assert(t0.n()== t1.n());
		tmp.n()=t0.n(); 
		tmp.t()=(t0.t()+t1.t())/2.0;
		return tmp;
	}

};

/*
Versione Della Midpoint basata sul paper:
S. Karbacher, S. Seeger, G. Hausler
A non linear subdivision scheme for triangle meshes

	Non funziona!
	Almeno due problemi:
	1) il verso delle normali influenza il risultato (e.g. si funziona solo se le normali divergono)
		 Risolvibile controllando se le normali divergono
  2) gli archi vanno calcolati sul piano definito dalla normale interpolata e l'edge.
		 funziona molto meglio nelle zone di sella e non semplici.

*/
template<class MESH_TYPE>
struct MidPointArcNaive : public std::unary_function< face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{
	typename MESH_TYPE::CoordType operator()(face::Pos<typename MESH_TYPE::FaceType>  ep)
	{

		typename MESH_TYPE::CoordType vp = (ep.f->V(ep.z)->P()+ep.f->V1(ep.z)->P())/2.0;
		typename MESH_TYPE::CoordType  n = (ep.f->V(ep.z)->N()+ep.f->V1(ep.z)->N())/2.0;
		n.Normalize();
		typename MESH_TYPE::CoordType d0 = ep.f->V(ep.z)->P() - vp;
		typename MESH_TYPE::CoordType d1 = ep.f->V1(ep.z)->P()- vp;
		typename MESH_TYPE::ScalarType d=Distance(ep.f->V(ep.z)->P(),ep.f->V1(ep.z)->P())/2.0;

		typename MESH_TYPE::ScalarType cosa0=ep.f->V(ep.z)->N()*n;
		typename MESH_TYPE::ScalarType cosa1=ep.f->V1(ep.z)->N()*n;
		typename MESH_TYPE::ScalarType cosb0=(d0*n)/d;
		typename MESH_TYPE::ScalarType cosb1=(d1*n)/d;

		typename MESH_TYPE::ScalarType delta0=d*(cosb0 +sqrt( ((1-cosb0*cosb0)*(1-cosa0))/(1+cosa0)) );
		typename MESH_TYPE::ScalarType delta1=d*(cosb1 +sqrt( ((1-cosb1*cosb1)*(1-cosa1))/(1+cosa1)) );
		
		return vp+n*(delta0+delta1)/2.0;
	}
};



/*

A partire da una mesh raffina una volta tutti i lati dei triangoli minore di thr 
Se RefineSelected == true allora raffina SOLO le facce selezionate 
i cui edge sono piu'corti di thr.

I nuovi vertici e facce della mesh sono aggiunte in fondo 
Requirement: Topologia (in effetti se non si usa la il raffinamento per selezione non servirebbe)

Restituisce false se non raffina nemmeno una faccia.

Si assume che se la mesh ha dati per wedge la funzione di midpoint interpoli i nuovi wedge
tutti uguali per tutti i wedge sulla stessa 'vecchia' faccia.

*/

// binary predicate che dice quando splittare un edge 
// la refine usa qt funzione di default: raffina se l'edge^2 e' piu lungo di thr2


template <class MESH_TYPE, class FLT>
class EdgeLen
{
	public:
  FLT thr2;
	bool operator()(face::Pos<typename MESH_TYPE::FaceType> ep) const
	{
		return SquaredDistance(ep.f->V(ep.z)->P(), ep.f->V1(ep.z)->P())>thr2;
	}
};
/*
template<class MESH_TYPE, class MIDPOINT>
bool Refine(MESH_TYPE &m, MIDPOINT mid, typename MESH_TYPE::ScalarType thr=0,bool RefineSelectedP=false)
{
	volatile RefineW<MESH_TYPE,MIDPOINT,EdgeLen<typename MESH_TYPE::ScalarType>,true> RT;
	volatile RefineW<MESH_TYPE,MIDPOINT,EdgeLen<typename MESH_TYPE::ScalarType>,false> RF;

	bool retval;
	if(RefineSelectedP)   retval=RT.RefineT(m,mid,thr);
	if(!RefineSelectedP)	retval=RF.RefineT(m,mid,thr);
	return retval;
}

template<class MESH_TYPE, class MIDPOINT, class EDGEPRED>
bool RefineE(MESH_TYPE &m, MIDPOINT mid, EDGEPRED ep, bool RefineSelectedP=false)
{
	RefineW<MESH_TYPE,MIDPOINT,EDGEPRED,true> RT;
	RefineW<MESH_TYPE,MIDPOINT,EDGEPRED,false> RF;

	bool retval;
	if(RefineSelectedP)   retval=RT.RefineT(m,mid,ep);
	if(!RefineSelectedP)	retval=RF.RefineT(m,mid,ep);
	return retval;
}
*/
/*********************************************************/
/*********************************************************/
/*********************************************************/

template<class MESH_TYPE,class MIDPOINT>
bool Refine(MESH_TYPE &m, MIDPOINT mid, typename MESH_TYPE::ScalarType thr=0,bool RefineSelected=false, CallBackPos *cb = 0)
{
	EdgeLen <MESH_TYPE, typename MESH_TYPE::ScalarType> ep;
	ep.thr2=thr*thr;
  return RefineE(m,mid,ep,RefineSelected,cb);
}

template<class MESH_TYPE,class MIDPOINT, class EDGEPRED>
bool RefineE(MESH_TYPE &m, MIDPOINT mid, EDGEPRED ep,bool RefineSelected=false, CallBackPos *cb = 0)
{
	int j,NewVertNum=0,NewFaceNum=0;
	typedef std::pair<typename MESH_TYPE::VertexPointer,typename MESH_TYPE::VertexPointer> vvpair;
	std::map<vvpair,typename MESH_TYPE::VertexPointer> Edge2Vert;
	
	// First Loop: We analyze the mesh to compute the number of the new faces and new vertices 
	typename MESH_TYPE::FaceIterator fi;
  int step=0,PercStep=m.fn/33;
  if(PercStep==0) PercStep=1;
	for(fi=m.face.begin(),j=0;fi!=m.face.end();++fi) if(!(*fi).IsD())
  {
	 if(cb && (++step%PercStep)==0)(*cb)(step/PercStep,"Refining...");
	    for(j=0;j<3;j++){
				if(ep(face::Pos<typename MESH_TYPE::FaceType> (&*fi,j)) && 
					(!RefineSelected || ((*fi).IsS() && (*fi).FFp(j)->IsS())) ){
					++NewFaceNum;
					if(  ((*fi).V(j)<(*fi).V1(j))  || 	(*fi).IsB(j)  )  
						++NewVertNum;
				}
		}
  } // end face loop
	if(NewVertNum==0) return false;
	typename MESH_TYPE::VertexIterator lastv = tri::Allocator<MESH_TYPE>::AddVertices(m,NewVertNum);
//	typename MESH_TYPE::VertexIterator lastv=m.AddVertices(NewVertNum);
	
	// Secondo Ciclo si inizializza la mappa da edge a vertici
	// e la posizione dei nuovi vertici
	//j=0;
  for(fi=m.face.begin();fi!=m.face.end();++fi) if(!(*fi).IsD())
  {
	   if(cb && (++step%PercStep)==0)(*cb)(step/PercStep,"Refining...");
     for(j=0;j<3;j++)
			if(ep(face::Pos<typename MESH_TYPE::FaceType> (&*fi,j))  && 
					(!RefineSelected || ((*fi).IsS() && (*fi).FFp(j)->IsS())) )
				if((*fi).V(j)<(*fi).V1(j) || (*fi).IsB(j)){
						mid( (*lastv), face::Pos<typename MESH_TYPE::FaceType> (&*fi,j));
						//(*lastv).P()=((*fi).V(j)->P()+(*fi).V1(j)->P())/2;
						Edge2Vert[ vvpair((*fi).V(j),(*fi).V1(j)) ] = &*lastv;
						++lastv;
				}
  }
	assert(lastv==m.vert.end());

	typename MESH_TYPE::FaceIterator lastf = tri::Allocator<MESH_TYPE>::AddFaces(m,NewFaceNum);
//	MESH_TYPE::FaceIterator lastf = m.AddFaces(NewFaceNum);
//    int ddd=0; distance(m.face.begin(),lastf,ddd);
	typename MESH_TYPE::FaceIterator oldendf=lastf; 
	
/*
          v0

   
          f0

    mp01      mp02

          f3
      f1       f2

 v1      mp12       v2

*/

	typename MESH_TYPE::VertexPointer vv[6]; // i sei vertici in gioco 
																		//     0..2 vertici originali del triangolo 
																		//     3..5 mp01, mp12, mp20 midpoints of the three edges
	typename MESH_TYPE::FacePointer nf[4];   // le quattro facce in gioco.

  typename MESH_TYPE::FaceType::TexCoordType wtt[6];  // per ogni faccia sono al piu' tre i nuovi valori 
																							 // di texture per wedge (uno per ogni edge) 

	int fca=0,fcn =0;
	for(fi=m.face.begin();fi!=oldendf;++fi) if(!(*fi).IsD())
		{
	      if(cb && (++step%PercStep)==0)(*cb)(step/PercStep,"Refining...");
        fcn++;
				vv[0]=(*fi).V(0);
				vv[1]=(*fi).V(1);
				vv[2]=(*fi).V(2);
				bool e0=ep(face::Pos<typename MESH_TYPE::FaceType> (&*fi,0));
				bool e1=ep(face::Pos<typename MESH_TYPE::FaceType> (&*fi,1));
				bool e2=ep(face::Pos<typename MESH_TYPE::FaceType> (&*fi,2));

				if(e0) 
						if((*fi).V(0)<(*fi).V(1)|| (*fi).IsB(0)) vv[3]=Edge2Vert[ vvpair((*fi).V(0),(*fi).V(1)) ];
																										 else vv[3]=Edge2Vert[ vvpair((*fi).V(1),(*fi).V(0)) ];
				else vv[3]=0;
				if(e1)
						if((*fi).V(1)<(*fi).V(2)|| (*fi).IsB(1)) vv[4]=Edge2Vert[ vvpair((*fi).V(1),(*fi).V(2)) ];
																										 else vv[4]=Edge2Vert[ vvpair((*fi).V(2),(*fi).V(1)) ];
				else vv[4]=0;
				if(e2)
						if((*fi).V(2)<(*fi).V(0)|| (*fi).IsB(2)) vv[5]=Edge2Vert[ vvpair((*fi).V(2),(*fi).V(0)) ];
																										 else vv[5]=Edge2Vert[ vvpair((*fi).V(0),(*fi).V(2)) ];
				else vv[5]=0;
				int ind=((&*vv[3])?1:0)+((&*vv[4])?2:0)+((&*vv[5])?4:0);
				
				nf[0]=&*fi;
				int i;
				for(i=1;i<SplitTab[ind].TriNum;++i){
						nf[i]=&*lastf; ++lastf; fca++;
						if(RefineSelected || (*fi).IsS()) (*nf[i]).SetS();
				}
        
        if(tri::HasPerWedgeTexCoord(m))
					for(i=0;i<3;++i)	{
						wtt[i]=(*fi).WT(i);
						wtt[3+i]=mid.WedgeInterp((*fi).WT(i),(*fi).WT((i+1)%3));
					}

				int orgflag=	(*fi).UberFlags();
				for(i=0;i<SplitTab[ind].TriNum;++i)
					for(j=0;j<3;++j){
						(*nf[i]).V(j)=&*vv[SplitTab[ind].TV[i][j]];
						
						if(tri::HasPerWedgeTexCoord(m)) //analogo ai vertici...
									(*nf[i]).WT(j)=wtt[SplitTab[ind].TV[i][j]];

						assert((*nf[i]).V(j)!=0);
						if(SplitTab[ind].TE[i][j]!=3){
							if(orgflag & (MESH_TYPE::FaceType::BORDER0<<(SplitTab[ind].TE[i][j]))) 
								(*nf[i]).SetB(j); 
							else
								(*nf[i]).ClearB(j);
						} 
						else (*nf[i]).ClearB(j);						
					}

		if(SplitTab[ind].TriNum==3 && 
							SquaredDistance(vv[SplitTab[ind].swap[0][0]]->P(),vv[SplitTab[ind].swap[0][1]]->P()) < 
							SquaredDistance(vv[SplitTab[ind].swap[1][0]]->P(),vv[SplitTab[ind].swap[1][1]]->P()) )
							{ // swap the last two triangles
								(*nf[2]).V(1)=(*nf[1]).V(0);
								(*nf[1]).V(1)=(*nf[2]).V(0);
								if(tri::HasPerWedgeTexCoord(m)){ //swap also textures coordinates
									(*nf[2]).WT(1)=(*nf[1]).WT(0);
									(*nf[1]).WT(1)=(*nf[2]).WT(0);
								}
								
								if((*nf[1]).IsB(0)) (*nf[2]).SetB(1); else (*nf[2]).ClearB(1);
								if((*nf[2]).IsB(0)) (*nf[1]).SetB(1); else (*nf[1]).ClearB(1);
								(*nf[1]).ClearB(0);
								(*nf[2]).ClearB(0);
							}
		}
	
    // m.fn= m.face.size();

	assert(lastf==m.face.end());	
	assert(!m.vert.empty());
	 for(fi=m.face.begin();fi!=m.face.end();++fi) if(!(*fi).IsD()){
			assert((*fi).V(0)>=&*m.vert.begin() && (*fi).V(0)<=&m.vert.back() );
			assert((*fi).V(1)>=&*m.vert.begin() && (*fi).V(1)<=&m.vert.back() );
			assert((*fi).V(2)>=&*m.vert.begin() && (*fi).V(2)<=&m.vert.back() );
	 }
	vcg::tri::UpdateTopology<MESH_TYPE>::FaceFace(m);	
	return true;
}
/*************************************************************************/

/*
Modified Butterfly interpolation scheme, 
as presented in 
Zorin, Schroeder
Subdivision for modeling and animation
Siggraph 2000 Course Notes
*/

/*

    vul-------vu--------vur
		  \      /  \      /
			 \    /    \    /
        \  /  fu  \  /
         vl--------vr
        /  \  fd  /  \
       /    \    /    \
      /      \  /      \
    vdl-------vd--------vdr

*/

template<class MESH_TYPE>
struct MidPointButterfly : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{
	void operator()(typename MESH_TYPE::VertexType &nv, face::Pos<typename MESH_TYPE::FaceType>  ep)
	{	
		face::Pos<typename MESH_TYPE::FaceType> he(ep.f,ep.z,ep.f->V(ep.z));
		typename MESH_TYPE::CoordType *vl,*vr;
		typename MESH_TYPE::CoordType *vl0,*vr0; 
		typename MESH_TYPE::CoordType *vu,*vd,*vul,*vur,*vdl,*vdr;
		vl=&he.v->P();
		he.FlipV();
		vr=&he.v->P();
		
		if( MESH_TYPE::HasPerVertexColor())
			nv.C().lerp(ep.f->V(ep.z)->C(),ep.f->V1(ep.z)->C(),.5f);

		if(he.IsBorder())
		{
			he.NextB();
			vr0=&he.v->P();
			he.FlipV();
			he.NextB();
			assert(&he.v->P()==vl);
			he.NextB();
			vl0=&he.v->P();
			nv.P()=((*vl)+(*vr))*(9.0/16.0)-((*vl0)+(*vr0))/16.0 ;
		}
		else 
		{
			he.FlipE();he.FlipV();
			vu=&he.v->P();
			he.FlipF();he.FlipE();he.FlipV(); 
			vur=&he.v->P();
			he.FlipV();he.FlipE();he.FlipF(); assert(&he.v->P()==vu); // back to vu (on the right)
			he.FlipE();
			he.FlipF();he.FlipE();he.FlipV();
			vul=&he.v->P();
			he.FlipV();he.FlipE();he.FlipF(); assert(&he.v->P()==vu); // back to vu (on the left)
			he.FlipV();he.FlipE();he.FlipF(); assert(&he.v->P()==vl);// again on vl (but under the edge)
			he.FlipE();he.FlipV();
			vd=&he.v->P();
			he.FlipF();he.FlipE();he.FlipV();
			vdl=&he.v->P();
			he.FlipV();he.FlipE();he.FlipF(); assert(&he.v->P()==vd);// back to vd (on the right)
			he.FlipE();
			he.FlipF();he.FlipE();he.FlipV();
			vdr=&he.v->P();

			nv.P()=((*vl)+(*vr))/2.0+((*vu)+(*vd))/8.0 - ((*vul)+(*vur)+(*vdl)+(*vdr))/16.0;
			}
	}

	/// Aggiunte in modo grezzo le due wedge interp
	Color4<typename MESH_TYPE::ScalarType> WedgeInterp(Color4<typename MESH_TYPE::ScalarType> &c0, Color4<typename MESH_TYPE::ScalarType> &c1)
	{
		Color4<typename MESH_TYPE::ScalarType> cc;
		return cc.lerp(c0,c1,0.5f);
	}

	template<class FL_TYPE>
	TexCoord2<FL_TYPE,1> WedgeInterp(TexCoord2<FL_TYPE,1> &t0, TexCoord2<FL_TYPE,1> &t1)
	{
		TexCoord2<FL_TYPE,1> tmp;
		assert(t0.n()== t1.n());
		tmp.n()=t0.n(); 
		tmp.t()=(t0.t()+t1.t())/2.0;
		return tmp;
	}
};


#if 0
			int rule=0;
			if(vr==vul) rule+=1;
			if(vl==vur) rule+=2;
			if(vl==vdr) rule+=4;
			if(vr==vdl) rule+=8;
			switch(rule){
/*      */
/*      */			case  0 :	return ((*vl)+(*vr))/2.0+((*vu)+(*vd))/8.0 - ((*vul)+(*vur)+(*vdl)+(*vdr))/16.0;
/* ul   */  		case  1 : return (*vl*6 + *vr*10 + *vu + *vd*3 - *vur - *vdl -*vdr*2 )/16.0; 
/* ur   */  		case  2 : return (*vr*6 + *vl*10 + *vu + *vd*3 - *vul - *vdr -*vdl*2 )/16.0; 
/* dr   */  		case  4 : return (*vr*6 + *vl*10 + *vd + *vu*3 - *vdl - *vur -*vul*2 )/16.0; 
/* dl   */  		case  8 : return (*vl*6 + *vr*10 + *vd + *vu*3 - *vdr - *vul -*vur*2 )/16.0; 
/* ul,ur */  		case  3 : return (*vl*4 + *vr*4 + *vd*2 + - *vdr - *vdl )/8.0; 
/* dl,dr */  		case 12 : return (*vl*4 + *vr*4 + *vu*2 + - *vur - *vul )/8.0; 

/* ul,dr */  		case  5 :
/* ur,dl */  		case 10 :						
								default:				
									return (*vl+ *vr)/2.0; 
			}



#endif
/*
    vul-------vu--------vur
		  \      /  \      /
			 \    /    \    /
        \  /  fu  \  /
         vl--------vr
        /  \  fd  /  \
       /    \    /    \
      /      \  /      \
    vdl-------vd--------vdr

*/

// Versione modificata per tenere di conto in meniara corretta dei vertici con valenza alta

template<class MESH_TYPE>
struct MidPointButterfly2 : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{
	typename MESH_TYPE::CoordType operator()(face::Pos<typename MESH_TYPE::FaceType>  ep)
	{	
double Rules[11][10] = 
{
	{.0}, // valenza 0 
	{.0}, // valenza 1 
	{.0}, // valenza 2 
	{  .4166666667, -.08333333333 , -.08333333333  }, // valenza 3 
	{  .375       ,  .0           ,  -0.125        ,  .0          }, // valenza 4											
	{  .35        ,  .03090169945 ,  -.08090169945 , -.08090169945,  .03090169945	}, // valenza 5	
	{  .5         ,  .125         ,  -0.0625       ,  .0          ,  -0.0625      , 0.125       }, // valenza 6	
	{  .25        ,  .1088899050  , -.06042933822  , -.04846056675, -.04846056675, -.06042933822,  .1088899050  }, // valenza 7	  
	{  .21875     ,  .1196383476  , -.03125        , -.05713834763, -.03125      , -.05713834763, -.03125      ,.1196383476  }, // valenza 8	  
	{  .1944444444,  .1225409480  , -.00513312590  , -.05555555556, -.03407448880, -.03407448880, -.05555555556, -.00513312590, .1225409480  }, // valenza 9	  
	{  .175       ,  .1213525492  ,  .01545084973  , -.04635254918, -.04045084973, -.025        , -.04045084973, -.04635254918,  .01545084973,  .1213525492  } // valenza 10	  
};

face::Pos<typename MESH_TYPE::FaceType> he(ep.f,ep.z,ep.f->V(ep.z));
	typename MESH_TYPE::CoordType *vl,*vr;
	vl=&he.v->P();
	vr=&he.VFlip()->P();
	if(he.IsBorder())
		{he.FlipV();
		typename MESH_TYPE::CoordType *vl0,*vr0; 
			he.NextB();
			vr0=&he.v->P();
			he.FlipV();
			he.NextB();
			assert(&he.v->P()==vl);
			he.NextB();
			vl0=&he.v->P();
			return ((*vl)+(*vr))*(9.0/16.0)-((*vl0)+(*vr0))/16.0 ;
		}

	int kl=0,kr=0; // valence of left and right vertices
	bool bl=false,br=false; // if left and right vertices are of border
  face::Pos<typename MESH_TYPE::FaceType> heStart=he;assert(he.v->P()==*vl);
	do { // compute valence of left vertex
		he.FlipE();he.FlipF();
		if(he.IsBorder()) bl=true; 
		++kl;
	}	while(he!=heStart);
	
	he.FlipV();heStart=he;assert(he.v->P()==*vr);
	do { // compute valence of right vertex
		he.FlipE();he.FlipF();
		if(he.IsBorder()) br=true; 
		++kr;
	}	while(he!=heStart);
  if(br||bl) return MidPointButterfly<MESH_TYPE>()( ep );
	if(kr==6 && kl==6) return MidPointButterfly<MESH_TYPE>()( ep );
	// TRACE("odd vertex among valences of %i %i\n",kl,kr);
	typename MESH_TYPE::CoordType newposl=*vl*.75, newposr=*vr*.75;
	he.FlipV();heStart=he; assert(he.v->P()==*vl);
	int i=0;
	if(kl!=6) 
	do { // compute position  of left vertex
		newposl+= he.VFlip()->P() * Rules[kl][i];
		he.FlipE();he.FlipF();
		++i;
	}	while(he!=heStart);
	i=0;he.FlipV();heStart=he;assert(he.v->P()==*vr);
	if(kr!=6)
	do { // compute position of right vertex
		newposr+=he.VFlip()->P()* Rules[kr][i];
		he.FlipE();he.FlipF();
		++i;
	}	while(he!=heStart);
	if(kr==6) return newposl;
	if(kl==6) return newposr;
	return newposl+newposr;
	}
};

/*
// Nuovi punti (e.g. midpoint)
template<class MESH_TYPE>
struct OddPointLoop : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{


}

// vecchi punti
template<class MESH_TYPE>
struct EvenPointLoop : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{
}
*/

template<class MESH_TYPE>
struct MidPointPlane : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{
	Plane3<typename MESH_TYPE::ScalarType> pl;
	typedef Point3<typename MESH_TYPE::ScalarType> Point3x;
	
	void operator()(typename MESH_TYPE::VertexType &nv, face::Pos<typename MESH_TYPE::FaceType> ep){
		Point3x &p0=ep.f->V0(ep.z)->P();
		Point3x &p1=ep.f->V1(ep.z)->P();
		double pp= Distance(p0,pl)/(Distance(p0,pl) - Distance(p1,pl));
		
    nv.P()=p1*pp + p0*(1.0-pp);
	}

	Color4<typename MESH_TYPE::ScalarType> WedgeInterp(Color4<typename MESH_TYPE::ScalarType> &c0, Color4<typename MESH_TYPE::ScalarType> &c1)
	{
		Color4<typename MESH_TYPE::ScalarType> cc;
		return cc.lerp(c0,c1,0.5f);
	}

	template<class FL_TYPE>
	TexCoord2<FL_TYPE,1> WedgeInterp(TexCoord2<FL_TYPE,1> &t0, TexCoord2<FL_TYPE,1> &t1)
	{
		TexCoord2<FL_TYPE,1> tmp;
		assert(t0.n()== t1.n());
		tmp.n()=t0.n(); 
		tmp.t()=(t0.t()+t1.t())/2.0;
		return tmp;
	}
};


template <class FLT>
class EdgeSplPlane
{
	public:
  Plane3<FLT> pl;
	bool operator()(const Point3<FLT> &p0, const  Point3<FLT> &p1) const
	{
		if(Distance(pl,p0)>0) {
			if(Distance(pl,p1)>0) return false;
			else return true;
		}
		else if(Distance(pl,p1)<=0) return false;
		return true;
	}
};


template<class MESH_TYPE>
struct MidPointSphere : public std::unary_function<face::Pos<typename MESH_TYPE::FaceType> , typename MESH_TYPE::CoordType>
{
	Sphere3<typename MESH_TYPE::ScalarType> sph;
	typedef Point3<typename MESH_TYPE::ScalarType> Point3x;
	
	void operator()(typename MESH_TYPE::VertexType &nv, face::Pos<typename MESH_TYPE::FaceType>  ep){
		Point3x &p0=ep.f->V0(ep.z)->P();
		Point3x &p1=ep.f->V1(ep.z)->P();
    nv.P()= sph.c+((p0+p1)/2.0 - sph.c ).Normalize();
	}

	Color4<typename MESH_TYPE::ScalarType> WedgeInterp(Color4<typename MESH_TYPE::ScalarType> &c0, Color4<typename MESH_TYPE::ScalarType> &c1)
	{
		Color4<typename MESH_TYPE::ScalarType> cc;
		return cc.lerp(c0,c1,0.5f);
	}

	template<class FL_TYPE>
	TexCoord2<FL_TYPE,1> WedgeInterp(TexCoord2<FL_TYPE,1> &t0, TexCoord2<FL_TYPE,1> &t1)
	{
		TexCoord2<FL_TYPE,1> tmp;
		assert(t0.n()== t1.n());
		tmp.n()=t0.n(); 
		tmp.t()=(t0.t()+t1.t())/2.0;
		return tmp;
	}
};


template <class FLT>
class EdgeSplSphere
{
	public:
  Sphere3<FLT> sph;
	bool operator()(const Point3<FLT> &p0, const  Point3<FLT> &p1) const
	{
		if(Distance(sph,p0)>0) {
			if(Distance(sph,p1)>0) return false;
			else return true;
		}
		else if(Distance(sph,p1)<=0) return false;
		return true;
	}
};

/*!
* Triangle split
*/

template<class TRIMESH_TYPE>
struct CenterPoint : public std::unary_function<typename TRIMESH_TYPE::FacePointer, typename TRIMESH_TYPE::CoordType>
{
	typename TRIMESH_TYPE::CoordType operator()(typename TRIMESH_TYPE::FacePointer f){
		return vcg::Barycenter<typename TRIMESH_TYPE::FaceType>(*f);
	}
};

template<class TRIMESH_TYPE, class CenterPoint>
void TriSplit(typename TRIMESH_TYPE::FacePointer f,
							typename TRIMESH_TYPE::FacePointer f1,typename TRIMESH_TYPE::FacePointer f2,
							typename TRIMESH_TYPE::VertexPointer vB, CenterPoint	Center)
{
	vB->P() = Center(f);

	//i tre vertici della faccia da dividere
	typename TRIMESH_TYPE::VertexType* V0,*V1,*V2;
	V0 = f->V(0);
	V1 = f->V(1);
	V2 = f->V(2);

	//risistemo la faccia di partenza
	(*f).V(2) = &(*vB);
	//Faccia nuova #1
	(*f1).V(0) = &(*vB);
	(*f1).V(1) = V1;
	(*f1).V(2) = V2;
	//Faccia nuova #2
	(*f2).V(0) = V0;
	(*f2).V(1) = &(*vB);
	(*f2).V(2) = V2;

	if(f->HasFFAdjacency())
	{
		//adiacenza delle facce adiacenti a quelle aggiunte
		f->FFp(1)->FFp(f->FFi(1)) = f1;
		f->FFp(2)->FFp(f->FFi(2)) = f2;

		//adiacenza ff
		typename TRIMESH_TYPE::FacePointer FF0,FF1,FF2;
		FF0 = f->FFp(0);
		FF1 = f->FFp(1);
		FF2 = f->FFp(2);

		//Indici di adiacenza ff
		char FFi0,FFi1,FFi2;
		FFi0 = f->FFi(0);
		FFi1 = f->FFi(1);
		FFi2 = f->FFi(2);

		//adiacenza della faccia di partenza
		(*f).FFp(1) = &(*f1);
		(*f).FFi(1) = 0;
		(*f).FFp(2) = &(*f2);
		(*f).FFi(2) = 0;

		//adiacenza della faccia #1
		(*f1).FFp(0) = f;
		(*f1).FFi(0) = 1;

		(*f1).FFp(1) = FF1;
		(*f1).FFi(1) = FFi1;

		(*f1).FFp(2) = &(*f2);
		(*f1).FFi(2) = 1;

		//adiacenza della faccia #2
		(*f2).FFp(0) = f;
		(*f2).FFi(0) = 2;

		(*f2).FFp(1) = &(*f1);
		(*f2).FFi(1) = 2;

		(*f2).FFp(2) = FF2;
		(*f2).FFi(2) = FFi2;
	}
}


} // namespace vcg




#endif