/****************************************************************************
* 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. *
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****************************************************************************/
#ifndef __VCGLIB_HALFEDGE_
#define __VCGLIB_HALFEDGE_
#include <vector>
#include <vcg/complex/trimesh/allocate.h>
#include <vcg/complex/trimesh/clean.h>
#include <vcg/complex/trimesh/update/topology.h>
#include <vcg/complex/trimesh/base.h>
namespace vcg
{
namespace tri{
/// \ingroup trimesh
/// \headerfile edge_support.h vcg/complex/trimesh/edge_support.h
/// \brief This class is used to build edge based data structure from indexed data structure and viceversa
/**
*/
template <class MeshType >
class UpdateHalfEdges{
public:
typedef typename MeshType::VertexType VertexType;
typedef typename MeshType::VertexPointer VertexPointer;
typedef typename MeshType::VertexIterator VertexIterator;
typedef typename MeshType::HEdgePointer HEdgePointer;
typedef typename MeshType::HEdgeType HEdgeType;
typedef typename MeshType::EdgePointer EdgePointer;
typedef typename MeshType::EdgeType EdgeType;
typedef typename MeshType::EdgeIterator EdgeIterator;
typedef typename MeshType::HEdgeIterator HEdgeIterator;
typedef typename MeshType::FaceIterator FaceIterator;
typedef typename MeshType::FaceType FaceType;
struct VertexPairEdgePtr{
VertexPairEdgePtr(VertexPointer _v0,VertexPointer _v1,HEdgePointer _ep):v0(_v0),v1(_v1),ep(_ep){if(v0>v1) std::swap(v0,v1);}
const bool operator <(const VertexPairEdgePtr &o) const {return (v0 == o.v0)? (v1<o.v1):(v0<o.v0);}
const bool operator ==(const VertexPairEdgePtr &o) const {return (v0 == o.v0)&& (v1==o.v1);}
VertexPointer v0,v1;
HEdgePointer ep;
};
struct FacePtrInt{
FacePtrInt ( FaceType * _f,int _i):f(_f),i(_i){}
FaceType * f;
int i;
};
typedef std::vector<bool> BitVector;
/**
build a half-edge data structure from an indexed data structure. Note that the half-edges are allocated here for the first time.
If you have a mesh where there are already edges, they will be removed and the data lost, so do not use this function
to just "update" the topology of half edges.
**/
static void FromIndexed(MeshType & m){
assert(HasFVAdjacency(m));
assert(HasHOppAdjacency(m));
assert(HasHNextAdjacency(m));
assert(HasHEAdjacency(m));
typename MeshType::template PerFaceAttributeHandle<BitVector> flagVisited =
vcg::tri::Allocator<MeshType>::template AddPerFaceAttribute<BitVector>(m,"");
std::vector<FacePtrInt > borderEdges;
// allocate all new half edges
FaceIterator fi;
unsigned int n_edges = 0;
// count how many half edge to allocate
for(fi = m.face.begin(); fi != m.face.end(); ++fi) if(! (*fi).IsD())
{n_edges+=(*fi).VN();
for(int i = 0; i < (*fi).VN(); ++i)
if(vcg::face::IsBorder<FaceType>((*fi),(i)))
++n_edges;
}
m.hedge.clear();
m.hn = 0;
// allocate the half edges
typename MeshType::HEdgeIterator ei = vcg::tri::Allocator<MeshType>::AddHEdges(m,n_edges);
std::vector<VertexPairEdgePtr> all;
int firstEdge = 0;
for(fi = m.face.begin(); fi != m.face.end(); ++fi)if(!(*fi).IsD()){
assert((*fi).VN()>2);
if(flagVisited[*fi].empty()) {flagVisited[*fi].resize((*fi).VN());}
for(int i = 0; i < (*fi).VN(); ++i,++ei)
{
(*ei).HVp() = (*fi).V(i);
(*ei).HNp() = &m.hedge[firstEdge + (i +1) % (*fi).VN()];
if(MeshType::HEdgeType::HasHFAdjacency())
(*ei).HFp() = &(*fi);
if( MeshType::FaceType::HasFHAdjacency())
(*fi).FHp() = &(*ei);
if(MeshType::HEdgeType::HasHPrevAdjacency())
(*ei).HPp() = &m.hedge[firstEdge + (i +(*fi).VN()-1) % (*fi).VN()];
if(HasVHAdjacency(m))
(*ei).HVp()->VHp() = &(*ei);
all.push_back(VertexPairEdgePtr((*fi).V(i), (*fi).V((*fi).Next(i)),&(*ei)));// it will be used to link the hedges
if( vcg::face::IsBorder<FaceType>((*fi),(i)))
borderEdges.push_back(FacePtrInt(&(*fi),i));
}
firstEdge += (*fi).VN();
}
// add all the border hedges
int borderLength;
typename std::vector<FacePtrInt >::iterator ebi;
for( ebi = borderEdges.begin(); ebi != borderEdges.end(); ++ebi)
if( !flagVisited[(*ebi).f][(*ebi).i])// not already inserted
{
borderLength = 0;
vcg::face::Pos<FaceType> bp((*ebi).f,(*ebi).i);
//FaceType * start = (*ebi).f;
VertexType * start = ((*ebi).f)->V((*ebi).i);
do{
all.push_back( VertexPairEdgePtr ( bp.f->V( bp.f->Next(bp.z) ),bp.f->V( bp.z ),&(*ei)));
(*ei).HVp() = bp.f->V(bp.f->Next(bp.z)) ;
flagVisited[bp.f][bp.z] = true;
++ei;
bp.NextB();
++borderLength;
}while (bp.v != start);
//}while (bp.f != start);
// run over the border edges to link the adjacencies
for(int be = 0; be < borderLength; ++be)
{
if(MeshType::HEdgeType::HasHFAdjacency())
m.hedge[firstEdge + be].HFp() = NULL;
if(MeshType::HEdgeType::HasHPrevAdjacency())
m.hedge[firstEdge + be].HPp() = &m.hedge[firstEdge + (be +borderLength-1) % borderLength];
m.hedge[firstEdge + be].HNp() = &m.hedge[firstEdge + (be +1) % borderLength];
}
firstEdge+=borderLength;
}
vcg::tri::Allocator<MeshType>:: template DeletePerFaceAttribute<BitVector>(m,flagVisited );
std::sort(all.begin(),all.end());
assert(all.size() == n_edges);
for(unsigned int i = 0 ; i < all.size(); )
if(all[i] == all[i+1])
{
all[i].ep->HOp() = all[i+1].ep;
all[i+1].ep->HOp() = all[i].ep;
i+=2;
}
else
{
all[i].ep->HOp() = all[i].ep;
i+=1;
}
if(HasEHAdjacency(m) && HasHEAdjacency(m))
{
assert(m.edge.size() == 0 || m.edge.size() == n_edges/2);
if ( m.edge.size() == 0 )
{
m.en = 0;
// allocate the edges
typename MeshType::EdgeIterator edge_i = vcg::tri::Allocator<MeshType>::AddEdges(m,n_edges/2);
for(ei = m.hedge.begin(); ei != m.hedge.end(); ++ei)
{
if((*ei).HEp() == NULL)
{
(*ei).HEp() = &(*edge_i);
(*ei).HOp()->HEp() = &(*edge_i);
(*edge_i).EHp() = &(*ei);
++edge_i;
}
}
}
else
{
assert(HasEVAdjacency(m));
//update edge relations
typename MeshType::EdgeIterator ei1;
for( ei1 = m.edge.begin(); ei1 != m.edge.end(); ++ei1 )
for( ei = m.hedge.begin(); ei != m.hedge.end(); ++ei )
if ( ((*ei).HVp() == (*ei1).V(0)) && ((*ei).HOp()->HVp() == (*ei1).V(1)) )
{
// EH
(*ei1).EHp() = &(*ei);
// HE
(*ei).HEp() = &(*ei1);
(*ei).HOp()->HEp() = &(*ei1);
break;
}
}
}
}
/**
Checks pointers FHEp() are valid
**/
static bool CheckConsistency_FHp(MeshType & m){
assert(MeshType::FaceType::HasFHAdjacency());
FaceIterator fi;
for(fi = m.face.begin(); fi != m.face.end(); ++fi)
if(!(*fi).IsD()){
if((*fi).FHp() < &(*m.hedge.begin())) return false;
if((*fi).FHp() > &(m.hedge.back())) return false;
}
return true;
}
/**
Checks that half edges and face relation are consistent
**/
static bool CheckConsistency(MeshType & m){
assert(MeshType::HEdgeType::HasHNextAdjacency());
assert(MeshType::HEdgeType::HasHOppAdjacency());
assert(MeshType::HEdgeType::HasHVAdjacency());
assert(MeshType::HEdgeType::HasHEAdjacency());
assert(MeshType::FaceType::HasFHAdjacency());
//bool hasHEF = ( MeshType::HEdgeType::HasHFAdjacency());
bool hasHP = ( MeshType::HEdgeType::HasHPrevAdjacency());
FaceIterator fi;
HEdgePointer ep,ep1;
int cnt = 0;
if( MeshType::HEdgeType::HasHFAdjacency() )
{
int iDb = 0;
for(fi = m.face.begin(); fi != m.face.end(); ++fi,++iDb)
if(!(*fi).IsD())
{
ep = ep1 = (*fi).FHp();
do{
if(ep->IsD())
return false; // the hedge should not be connected, it has been deleted
if( ! ep->HFp())
return false;
if(ep->HFp() != &(*fi))
return false;// hedge is not pointing to the rigth face
ep = ep->HNp();
if(cnt++ > m.hn)
return false; // hedges are ill connected (HENp())
}while(ep!=ep1);
}
}
HEdgePointer epPrev;
HEdgeIterator hi;
//bool extEdge ;
for( hi = m.hedge.begin(); hi != m.hedge.end(); ++hi)
if(!(*hi).IsD())
{
//cnt = 0;
epPrev = ep = ep1 = &(*hi);
//do{
//extEdge = (ep->HFp()==NULL);
if(hasHP)
{
if( !ep->HPp())
return false;
if( ep->HPp() == ep)
return false; // the previous of an edge cannot be the edge itself
if( ep->HNp()->HPp() != ep)
return false; // next and prev relation are not mutual
if( ep->HPp()->IsD())
return false; //
}
if( ! ep->HOp() )
return false;
if( ep->HOp() == ep)
return false; // opposite relation is not mutual
if( ep->HOp()->IsD())
return false;
if( ep->HOp()->HOp() != ep)
return false; // opposite relation is not mutual
if( HasHFAdjacency(m) )
{
if(ep->HFp())
{
if( ep->HFp()->IsD())
return false; // pointed face must not be deleted
}
}
if( HasHEAdjacency(m) && (m.en!=0))
{
if( ! ep->HEp())
return false; //halfedge must point to an edge
if( ep->HEp()->IsD())
return false; // pointed edge must not be deleted
if(ep->HEp() != ep->HOp()->HEp())
return false; // he and opposite he must point to the same edge
if(ep->HEp()->EHp() != ep && ep->HEp()->EHp() != ep->HOp() )
return false; // halfedge points to an edge not pointing it or its opposite
}
if( !ep->HNp() )
return false;
if( ep->HNp() == ep )
return false; // the next of an hedge cannot be the hedge itself
if( ep->HNp()->IsD())
return false; //
if(hasHP)
if( ep->HNp()->HPp() != ep)
return false; //
if( HasHVAdjacency(m) )
{
if( ! ep->HVp() )
return false; // halfedge must point to a vertex
if( ep->HVp()->IsD() )
return false; // pointed vertex must not be deleted
if( HasVHAdjacency(m) )
if( ! (ep->HVp()->VHp()) )
return false; // halfedge points to a vertex pointing NULL
}
ep = ep->HNp();
if( ep->HVp() != epPrev->HOp()->HVp())
return false;
epPrev = ep;
// if(cnt++ > m.hn)
// return false; // edges are ill connected (HENp())
//}while(ep!=ep1);
}
if(HasEHAdjacency(m))
for(EdgeIterator ei = m.edge.begin(); ei != m.edge.end(); ++ei)
{
if(!(*ei).IsD())
{
if( !(*ei).EHp())
return false; //edge must have a valid pointer to his halfedge
if( (*ei).EHp()->HEp() != &(*ei) )
return false; // edge's halfedge must point to the edge itself
if( (*ei).EHp()->IsD())
return false;
}
}
if(HasVHAdjacency(m))
for(VertexIterator vi = m.vert.begin(); vi != m.vert.end(); ++vi)
{
if( !(*vi).IsD() )
if( (*vi).VHp() )
{
if( (*vi).VHp()->HVp() != &(*vi) )
return false;
if( (*vi).VHp()->IsD())
return false;
}
}
return true;
}
/** Set the relations HFp(), FHp() from a loop of edges to a face
*/
private:
static void SetRelationsLoopFace(HEdgeType * e0, FaceType * f){
assert(HEdgeType::HasHNextAdjacency());
assert(FaceType::HasFHAdjacency());
HEdgeType *e = e0;
assert(e!=NULL);
do{ e->HFp() = f; e = e->HNp(); } while(e != e0);
f->FHp() = e0;
}
/**
Merge the two faces. This will probably become a class template or a functor
*/
static void MergeFaces(FaceType *, FaceType *){}
/**
Find previous hedge in the loop
*/
static HEdgeType * PreviousEdge(HEdgeType * e0){
HEdgeType * ep = e0;
do{
if(ep->HNp() == e0) return ep;
ep = ep->HNp();
}while(ep!=e0);
assert(0); // degenerate loop
return 0;
}
public:
/** Adds an edge between the sources of e0 and e1 and set all the topology relations.
If the edges store the pointers to the faces then a new face is created.
<--- e1 ---- X <------e1_HEPp---
^
||
ei0 || ei1
||
v
----e0_HEPp-> X ----- e0 ------>
*/
static void AddHEdge(MeshType &m, HEdgeType * e0, HEdgeType * e1){
HEdgeType *iii =e0->HNp();
assert(e1!=e0->HNp());
assert(e0!=e1->HNp());
HEdgePointer tmp;
bool hasP = MeshType::HEdgeType::HasHPrevAdjacency();
assert(e0->HOp() != e1); // the hedge already exists
assert(e0!=e1->HNp());
std::vector<typename MeshType::HEdgePointer* > toUpdate;
toUpdate.push_back(&e0);
toUpdate.push_back(&e1);
HEdgeIterator ei0 = vcg::tri::Allocator<MeshType>::AddHEdges(m,2,toUpdate);
HEdgeIterator ei1 = ei0; ++ei1;
(*ei0).HNp() = e1;(*ei0).HVp() = e0->HVp();
(*ei1).HNp() = e0;(*ei1).HVp() = e1->HVp();
HEdgePointer e0_HEPp = 0,e1_HEPp = 0,ep =0;
if(hasP){
e0_HEPp = e0->HPp();
e1_HEPp = e1->HPp();
}else{// does not have pointer to previous, it must be computed
ep = e0;
do{
if(ep->HNp() == e0) e0_HEPp = ep;
if(ep->HNp() == e1) e1_HEPp = ep;
ep = ep->HNp();
}while(ep!=e0);
}
if(hasP){
(*ei0).HPp() = e0->HPp();
(*ei1).HPp() = e1->HPp();
e0->HPp() = &(*ei1);
e1->HPp() = &(*ei0);
}
e0_HEPp -> HNp() = &(*ei0);
e1_HEPp -> HNp() = &(*ei1);
(*ei0).HOp() = &(*ei1);
(*ei1).HOp() = &(*ei0);
if( HEdgeType::HasHFAdjacency() && FaceType::HasFHAdjacency()){
FaceIterator fi0 = vcg::tri::Allocator<MeshType>::AddFaces(m,1);
m.face.back().ImportData(*e0->HFp());
SetRelationsLoopFace(&(*ei0),e1->HFp()); // one loop to the old face
SetRelationsLoopFace(&(*ei1),&m.face.back()); // the other to the new face
}
}
/** Detach the topology relations of a given edge
<--- e->HENPp -X --- <---------eO_HEPp---
^
||
e || e->HEOp()
||
v
----e_HEPp--> X ----- e->HEOp->HENPp() ------>
*/
static void RemoveHEdge(MeshType &m, HEdgeType * e){
assert(MeshType::HEdgeType::HasHNextAdjacency());
assert(MeshType::HEdgeType::HasHOppAdjacency());
assert(MeshType::FaceType::HasFHAdjacency());
bool hasP = MeshType::HEdgeType::HasHPrevAdjacency();
HEdgePointer e_HEPp,eO_HEPp;
if(hasP){
e_HEPp = e->HPp();
eO_HEPp = e->HOp()->HPp();
}else{
e_HEPp = PreviousEdge(e);
eO_HEPp = PreviousEdge(e->HOp());
}
assert(e_HEPp->HNp() == e);
assert(eO_HEPp->HNp() == e->HOp());
e_HEPp->HNp() = e->HOp()->HNp();
eO_HEPp->HNp() = e-> HNp();
if(hasP) {
e->HOp()->HNp()->HPp() = e_HEPp;
e->HNp()->HPp() = eO_HEPp;
e->HPp() = NULL;
e-> HOp()->HPp() = NULL;
}
// take care of the faces
if(MeshType::HEdgeType::HasHFAdjacency()){
MergeFaces(e_HEPp->HFp(),eO_HEPp->HFp());
vcg::tri::Allocator<MeshType>::DeleteFace(m,*eO_HEPp->HFp());
SetRelationsLoopFace(e_HEPp,e_HEPp->HFp());
}
vcg::tri::Allocator<MeshType>::DeleteHEdge(m,*e->HOp());
vcg::tri::Allocator<MeshType>::DeleteHEdge(m,*e);
}
};// end class
template <class MeshType >
struct UpdateIndexed{
typedef typename MeshType::VertexType VertexType;
typedef typename MeshType::VertexPointer VertexPointer;
typedef typename MeshType::HEdgePointer HEdgePointer;
typedef typename MeshType::HEdgeType HEdgeType;
typedef typename MeshType::HEdgeIterator HEdgeIterator;
typedef typename MeshType::FaceIterator FaceIterator;
typedef typename MeshType::FaceType FaceType;
struct VertexPairEdgePtr{
VertexPairEdgePtr(VertexPointer _v0,VertexPointer _v1,HEdgePointer _ep):v0(_v0),v1(_v1),ep(_ep){if(v0>v1) std::swap(v0,v1);}
const bool operator <(const VertexPairEdgePtr &o) const {return (v0 == o.v0)? (v1<o.v1):(v0<o.v0);}
const bool operator ==(const VertexPairEdgePtr &o) const {return (v0 == o.v0)&& (v1==o.v1);}
VertexPointer v0,v1;
HEdgePointer ep;
};
/**
builds an indexed data structure from a half-edge data structure.
Note: if the half edge have the pointer to face
their relation FV (face-vertex) will be computed and the data possibly stored in the
face will be preserved.
**/
static void FromHalfEdges( MeshType & m ){
assert(HasFVAdjacency(m));
assert(MeshType::HEdgeType::HasHNextAdjacency());
assert(MeshType::HEdgeType::HasHVAdjacency());
assert(MeshType::HEdgeType::HasHOppAdjacency());
assert(MeshType::FaceType::HasFHAdjacency());
bool hasHEF;
//bool createFace,hasHEF,hasFHE;
// typename MeshType::template PerHEdgeAttributeHandle<bool> hV = Allocator<MeshType>::template AddPerHEdgeAttribute<bool>(m,"");
typename MeshType::HEdgeIterator ei;
typename MeshType::FacePointer fp;
typename MeshType::FaceIterator fi;
typename MeshType::HEdgePointer ep,epF;
//int vi = 0;
vcg::SimpleTempData<typename MeshType::HEdgeContainer,bool> hV(m.hedge);
hasHEF = (MeshType::HEdgeType::HasHFAdjacency());
assert( !hasHEF || (hasHEF && m.fn>0));
// if the edgetype has the pointer to face
// it is assumed the the edget2face pointer (HEFp) are correct
// and the faces are allocated
for ( ei = m.hedge.begin(); ei != m.hedge.end(); ++ei)
if(!(*ei).IsD()) // it has not been deleted
if(!hasHEF || ( hasHEF && (*ei).HFp()!=NULL)) // if it has a pointer to the face it is
// not null (i.e. it is not a border edge)
if(!hV[(*ei)] ) // it has not be visited yet
{
if(!hasHEF)// if it has
fp = &(* Allocator<MeshType>::AddFaces(m,1));
else
fp = (*ei).HFp();
ep = epF = &(*ei);
std::vector<VertexPointer> vpts;
do{vpts.push_back((*ep).HVp()); ep=ep->HNp();}while(ep!=epF);
//int idbg =fp->VN();
if(fp->VN() != vpts.size()){
fp->Dealloc();
fp ->Alloc(vpts.size());
}
//int idbg1 =fp->VN();
for(unsigned int i = 0; i < vpts.size();++i) fp ->V(i) = vpts[i];// set the pointer from face to vertex
hV[(*ei)] = true;
}
//Allocator<MeshType>::DeletePerHEdgeAttribute(m,hV);
}
};
} // end namespace vcg
}
#endif // __VCGLIB_EDGE_SUPPORT