vcglib/vcg/complex/trimesh/edge_collapse.h

281 lines
8.4 KiB
C++

/****************************************************************************
* 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. *
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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 *
* 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
****************************************************************************/
#ifndef __VCG_TETRA_TRI_COLLAPSE
#define __VCG_TETRA_TRI_COLLAPSE
#include<vcg/simplex/face/pos.h>
#include<vcg/simplex/face/topology.h>
#include<map>
/** \addtogroup trimesh */
/*@{*/
/** This a static utlity class for the edge collapse.
It provides a common set of useful function for actually making an edge collapse over a trimesh. See also
**/
namespace vcg{
namespace tri{
template <class TRI_MESH_TYPE>
class EdgeCollapse
{
public:
/// The tetrahedral mesh type
typedef TRI_MESH_TYPE TriMeshType;
/// The tetrahedron type
typedef typename TriMeshType::FaceType FaceType;
/// The vertex type
typedef typename FaceType::VertexType VertexType;
/// The vertex iterator type
typedef typename TriMeshType::VertexIterator VertexIterator;
/// The tetra iterator type
typedef typename TriMeshType::FaceIterator FaceIterator;
/// The coordinate type
typedef typename FaceType::VertexType::CoordType CoordType;
/// The scalar type
typedef typename TriMeshType::VertexType::ScalarType ScalarType;
///the container of tetrahedron type
typedef typename TriMeshType::FaceContainer FaceContainer;
///the container of vertex type
typedef typename TriMeshType::VertContainer VertContainer;
///half edge type
typedef typename vcg::face::Pos<FaceType> PosType;
/// vector of pos
typedef typename std::vector<PosType> PosVec;
///of VFIterator
typedef typename vcg::face::VFIterator<FaceType> VFI;
/// vector of VFIterator
typedef typename std::vector<vcg::face::VFIterator<FaceType> > VFIVec;
/// Default Constructor
EdgeCollapse()
{
};
~EdgeCollapse()
{
};
struct Edge{
VertexType* v0,v1;
Edge( const VertexType*& a,const VertexType*& b){
assert(a!=b);
if(a<b)
{v0=a;v1=b;}
else
{v1=a;v0=b;}
}
const bool operator <(const Edge & e) const {
return (v0==e.v0)?(v1<e.v1):(v0<e.v0);
}
const bool operator ==(const Edge & e) const {
return (v0==e.v0)&&(v1==e.v1);
}
};
static VFIVec & AV0(){static VFIVec av0; return av0;}
static VFIVec & AV1(){static VFIVec av1; return av1;}
static VFIVec & AV01(){static VFIVec av01; return av01;}
void FindSets(PosType p)
{
VertexType * v0 = p.V(0);
VertexType * v1 = p.V(1);
AV0().clear(); // Facce incidenti in v0
AV1().clear(); // Facce incidenti in v1
AV01().clear(); // Facce incidenti in v0 e v1
VFI x;
for( x.f = v0->VFp(), x.z = v0->VFi(); x.f!=0; ++x)
{
int zv1 = -1;
for(int j=0;j<3;++j)
if( x.f->V(j)==&*v1 ) {
zv1 = j;
break;
}
if(zv1==-1) AV0().push_back( x ); // la faccia x.f non ha il vertice v1 => e' incidente solo in v0
else AV01().push_back( x );
}
for( x.f = v1->VFp(), x.z = v1->VFi(); x.f!=0; ++x )
{
int zv0 = -1;
for(int j=0;j<3;++j)
if( x.f->V(j)==&*v0 ) {
zv0 = j;
break;
}
if(zv0==-1) AV1().push_back( x ); // la faccia x.f non ha il vertice v1 => e' incidente solo in v0
}
}
bool LinkConditions(PosType pos){
const int ADJ_1 = TriMeshType::VertexType::NewBitFlag();
const int ADJ_E = TriMeshType::VertexType::NewBitFlag();
//enum {ADJ_1= MeshType::VertexType::USER0,
// ADJ_E= MeshType::VertexType::USER0<<1} ;
// const int ALLADJ = ADJ_1|ADJ_E;
const int NOTALLADJ = ~(ADJ_1 | ADJ_E | TriMeshType::VertexType::VISITED);
const int NOTALLADJ1 = ~(ADJ_E | TriMeshType::VertexType::VISITED);
//EdgePosB<MeshType::face_type::face_base> x;
typename vcg::face::VFIterator<FaceType> x;
// Clear visited and adj flag for all vertices adj to v0;
for(x.f = pos.V(0)->VFp(), x.z = pos.V(0)->VFi(); x.f!=0; ++x ) {
x.f->V1(x.z)->Flags() &= NOTALLADJ;
x.f->V2(x.z)->Flags() &= NOTALLADJ;
}
// Clear visited flag for all vertices adj to v1 and set them adj1 to v1;
for(x.f = pos.V(1)->VFp(), x.z = pos.V(1)->VFi(); x.f!=0; ++x ) {
x.f->V1(x.z)->Flags() &= NOTALLADJ1;
x.f->V2(x.z)->Flags() &= NOTALLADJ1;
}
// Mark vertices adj to v1 as ADJ_1 and adj1 to v1;
for(x.f = pos.V(1)->VFp(), x.z = pos.V(1)->VFi(); x.f!=0; ++x ) {
if(x.f->V1(x.z)==pos.V(0)) x.f->V2(x.z)->Flags() |= ADJ_E | ADJ_1;
else x.f->V2(x.z)->Flags() |= ADJ_1;
if(x.f->V2(x.z)==pos.V(0)) x.f->V1(x.z)->Flags() |= ADJ_E | ADJ_1;
else x.f->V1(x.z)->Flags() |= ADJ_1;
}
// compute the number of:
int adj01=0; // vertices adjacents to both v0 and v1
int adje=0; // vertices adjacents to an egde (usually 2)
for(x.f = pos.V(0)->VFp(), x.z = pos.V(0)->VFi(); x.f!=0; ++x ) {
if(!x.f->V1(x.z)->IsV()) {
x.f->V1(x.z)->SetV();
if(x.f->V1(x.z)->Flags()&ADJ_1) ++adj01;
if(x.f->V1(x.z)->Flags()&ADJ_E) ++adje;
}
if(!x.f->V2(x.z)->IsV()) {
x.f->V2(x.z)->SetV();
if(x.f->V2(x.z)->Flags()&ADJ_1) ++adj01;
if(x.f->V2(x.z)->Flags()&ADJ_E) ++adje;
}
}
//bool val=TopoCheck2();
//if(val != (adj01==adje)) printf("Wrong topo %i %i\n",adj01,adje);
TriMeshType::VertexType::DeleteBitFlag(ADJ_E);
TriMeshType::VertexType::DeleteBitFlag(ADJ_1);
return (adj01==adje);
}
int DoCollapse(PosType & c, Point3<ScalarType> p)
{
FindSets(c);
typename VFIVec::iterator i;
int n_face_del =0 ;
//set Face Face topology
if (TriMeshType::HasFFTopology())
{
int e0=c.z;
int e1=c.f->FFi(c.z); //opposite edge
FaceType *f0=c.f;
FaceType *f1=f0->FFp(c.z);
//take right indexes
FaceType *f00=f0->FFp((e0+1)%3);
FaceType *f01=f0->FFp((e0+2)%3);
int If00=f0->FFi((e0+1)%3);
int If01=f0->FFi((e0+2)%3);
//then attach faces
f00->FFp(If00)=f01;
f00->FFi(If00)=If01;
f01->FFp(If01)=f00;
f01->FFi(If01)=If00;
//and the ones of face f1
f00=f1->FFp((e1+1)%3);
f01=f1->FFp((e1+2)%3);
If00=f1->FFi((e1+1)%3);
If01=f1->FFi((e1+2)%3);
//and attach faces
f00->FFp(If00)=f01;
f00->FFi(If00)=If01;
f01->FFp(If01)=f00;
f01->FFi(If01)=If00;
}
for(i=AV01().begin();i!=AV01().end();++i)
{
FaceType * f = ((*i).f);
assert(f->V((*i).z) == c.V(0));
vcg::face::VFDetach(*f,((*i).z+1)%3);
vcg::face::VFDetach(*((*i).f),((*i).z+2)%3);
((*i).f)->SetD();
n_face_del++;
}
//set Vertex Face topology
for(i=AV0().begin();i!=AV0().end();++i)
{
(*i).f->V((*i).z) = c.V(1); // In tutte le facce incidenti in v0, si sostituisce v0 con v1
(*i).f->VFp((*i).z) = (*i).f->V((*i).z)->VFp(); // e appendo la lista di facce incidenti in v1 a questa faccia
(*i).f->VFi((*i).z) = (*i).f->V((*i).z)->VFi();
(*i).f->V((*i).z)->VFp() = (*i).f;
(*i).f->V((*i).z)->VFi() = (*i).z;
}
/*TriMeshType::VertexType nv;*/
//* c.v[1]->Merge(*c.v[0]);
c.V(0)->SetD();
c.V(1)->P()=p;
return n_face_del;
}
};
}
}
#endif