/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2006 \/)\/ *
* 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 1.11 2006/06/08 13:55:16 cignoni
Added ColorPreserving Cellbase template.
Revision 1.10 2006/05/26 10:18:11 cignoni
Re-adapted to ms compilers
Revision 1.9 2006/05/25 09:37:14 cignoni
Many changes for the different interpretation of hash_set between gcc and .net. Probably to be completed.
Revision 1.8 2006/05/24 16:42:22 m_di_benedetto
Corrected bbox inflation amount in case of _cellsize != 0
Revision 1.7 2006/05/24 15:16:01 cignoni
better comment to the init parameters
Revision 1.6 2006/05/24 08:54:04 cignoni
Added missing std:: to swap
Revision 1.5 2006/05/21 06:40:31 cignoni
Added DoubleFace management
Revision 1.4 2006/05/19 20:49:03 m_di_benedetto
Added check for empty generated mesh (prevent call to mesh allocator with zero vertices or faces).
Revision 1.3 2006/05/18 22:20:53 m_di_benedetto
added check for deleted faces and modified/added std namespace qualifier.
Revision 1.2 2006/05/18 13:59:20 cignoni
Some minor optimizations
Revision 1.1 2006/05/16 21:56:06 cignoni
First working Version
****************************************************************************/
#ifndef __VCGLIB_CLUSTERING
#define __VCGLIB_CLUSTERING
#include<vcg/complex/trimesh/base.h>
#include <vcg/complex/trimesh/clean.h>
#include<vcg/space/triangle3.h>
#include<vcg/complex/trimesh/update/topology.h>
#include<vcg/space/index/grid_util.h>
#include <iostream>
#include <math.h>
#include <limits>
// some stuff for portable hashes...
#ifdef WIN32
#ifndef __MINGW32__
#include <hash_map>
#include <hash_set>
#define STDEXT stdext
#else
#include <ext/hash_map>
#include <ext/hash_set>
#define STDEXT __gnu_cxx
#endif
#else
#include <ext/hash_map>
#include <ext/hash_set>
#define STDEXT __gnu_cxx
#endif
namespace vcg{
namespace tri{
#define HASH_P0 73856093
#define HASH_P1 19349663
#define HASH_P2 83492791
class HashedPoint3i : public Point3i
{
public:
const size_t Hash() const
{
return (V(0)*HASH_P0 ^ V(1)*HASH_P1 ^ V(2)*HASH_P2);
}
operator size_t () const
{return Hash();}
};
// needed for gcc compilation
#ifndef _MSC_VER
}} namespace STDEXT {
template <> struct hash<vcg::tri::HashedPoint3i>{
inline size_t operator ()(const vcg::tri::HashedPoint3i &p) const {return size_t(p);}
};
} namespace vcg{ namespace tri{
#endif
//
template<class MeshType>
class AverageCell
{
typedef typename MeshType::CoordType CoordType;
typedef typename MeshType::FaceType FaceType;
public:
inline void Add(MeshType &m, FaceType &f, int i)
{
p+=f.cV(i)->cP();
// we prefer to use the un-normalized face normal so small faces facing away are dropped out
// and the resulting average is weighed with the size of the faces falling here.
n+=f.cN();
cnt++;
}
AverageCell(): p(0,0,0), n(0,0,0),cnt(0){}
CoordType p;
CoordType n;
int cnt;
int id;
CoordType Pos() const
{
return p/cnt;
}
Color4b Col() const {return Color4b::White;}
};
template<class MeshType>
class AverageColorCell
{
typedef typename MeshType::CoordType CoordType;
typedef typename MeshType::FaceType FaceType;
public:
inline void Add(MeshType &m, FaceType &f, int i)
{
p+=f.cV(i)->cP();
c+=CoordType(f.cV(i)->C()[0],f.cV(i)->C()[1],f.cV(i)->C()[2]);
// we prefer to use the un-normalized face normal so small faces facing away are dropped out
// and the resulting average is weighed with the size of the faces falling here.
n+=f.cN();
cnt++;
}
AverageColorCell(): p(0,0,0), n(0,0,0), c(0,0,0),cnt(0){}
CoordType p;
CoordType n;
CoordType c;
int cnt;
int id;
Color4b Col() const
{
return Color4b(c[0]/cnt,c[1]/cnt,c[2]/cnt,255);
}
CoordType Pos() const
{
return p/cnt;
}
};
/*
Metodo di clustering
*/
template<class MeshType, class CellType, bool Selected=true>
class Clustering
{
public:
typedef typename MeshType::ScalarType ScalarType;
typedef typename MeshType::CoordType CoordType;
typedef typename MeshType::VertexType VertexType;
typedef typename MeshType::FaceType FaceType;
typedef typename MeshType::VertexPointer VertexPointer;
typedef typename MeshType::VertexIterator VertexIterator;
typedef typename MeshType::FaceIterator FaceIterator;
// DuplicateFace == bool means that during the clustering doublesided surface (like a thin shell) that would be clustered to a single surface
// will be merged into two identical but opposite faces.
// So in practice:
// DuplicateFace=true a model with looks ok if you enable backface culling
// DuplicateFace=false a model with looks ok if you enable doublesided lighting and disable backfaceculling
bool DuplicateFaceParam;
class SimpleTri
{
public:
CellType *v[3];
const int ii(int i) const {return *((int *)(&(v[i])));}
bool operator < ( const SimpleTri &p) const {
return (v[2]!=p.v[2])?(v[2]<p.v[2]):
(v[1]!=p.v[1])?(v[1]<p.v[1]):
(v[0]<p.v[0]);
}
// Sort the vertex of the face maintaining the original face orientation (it only ensure that v0 is the minimum)
void sortOrient()
{
if(v[1] < v[0] && v[1] < v[2] ) { std::swap(v[0],v[1]); std::swap(v[1],v[2]); return; } // v1 was the minimum
if(v[2] < v[0] && v[2] < v[1] ) { std::swap(v[0],v[2]); std::swap(v[1],v[2]); return; } // v2 was the minimum
return; // v0 was the minimum;
}
void sort()
{
if(v[0] > v[1] ) std::swap(v[0],v[1]); // now v0 < v1
if(v[0] > v[2] ) std::swap(v[0],v[2]); // now v0 is the minimum
if(v[1] > v[2] ) std::swap(v[1],v[2]); // sorted!
}
// Hashing Function;
operator size_t () const
{
return (ii(0)*HASH_P0 ^ ii(1)*HASH_P1 ^ ii(2)*HASH_P2);
}
};
// The init function Take two parameters
// _size is the approximate total number of cells composing the grid surrounding the objects (usually a large number)
// eg _size==1.000.000 means a 100x100x100 grid
// _cellsize is the absolute lenght of the edge of the grid cell.
// eg _cellsize==2.0 means that all the vertexes in a 2.0x2.0x2.0 cell are clustered togheter
// Notes:
// _size is used only if the cell edge IS zero.
// _cellsize gives you an absolute measure of the maximum error introduced
// during the simplification (e.g. half of the cell edge lenght)
void Init(Box3<ScalarType> _mbb, int _size, ScalarType _cellsize=0)
{
Grid.bbox=_mbb;
///inflate the bb calculated
ScalarType infl = (_cellsize == (ScalarType)0) ? (Grid.bbox.Diag() / _size) : (_cellsize);
Grid.bbox.min-=CoordType(infl,infl,infl);
Grid.bbox.max+=CoordType(infl,infl,infl);
Grid.dim = Grid.bbox.max - Grid.bbox.min;
if( _cellsize==0)
BestDim( _size, Grid.dim, Grid.siz );
else
Grid.siz = Point3i::Construct(Grid.dim / _cellsize);
// find voxel size
Grid.voxel[0] = Grid.dim[0]/Grid.siz[0];
Grid.voxel[1] = Grid.dim[1]/Grid.siz[1];
Grid.voxel[2] = Grid.dim[2]/Grid.siz[2];
}
BasicGrid<ScalarType> Grid;
#ifdef _MSC_VER
STDEXT::hash_set<SimpleTri> TriSet;
typedef typename STDEXT::hash_set<SimpleTri>::iterator TriHashSetIterator;
#else
struct SimpleTriHashFunc{
inline size_t operator ()(const SimpleTri &p) const {return size_t(p);}
};
STDEXT::hash_set<SimpleTri,SimpleTriHashFunc> TriSet;
typedef typename STDEXT::hash_set<SimpleTri,SimpleTriHashFunc>::iterator TriHashSetIterator;
#endif
STDEXT::hash_map<HashedPoint3i,CellType> GridCell;
void Add(MeshType &m)
{
FaceIterator fi;
for(fi=m.face.begin();fi!=m.face.end();++fi)
{
if ((*fi).IsD())
{
continue;
}
HashedPoint3i pi;
SimpleTri st;
for(int i=0;i<3;++i)
{
Grid.PToIP((*fi).cV(i)->cP(), pi );
st.v[i]=&(GridCell[pi]);
st.v[i]->Add(m,*(fi),i);
}
if( (st.v[0]!=st.v[1]) && (st.v[0]!=st.v[2]) && (st.v[1]!=st.v[2]) )
{ // if we allow the duplication of faces we sort the vertex only partially (to maintain the original face orientation)
if(DuplicateFaceParam) st.sortOrient();
else st.sort();
TriSet.insert(st);
}
// printf("Inserted %8i triangles, clustered to %8i tri and %i cells\n",distance(m.face.begin(),fi),TriSet.size(),GridCell.size());
}
}
void Extract(MeshType &m)
{
m.Clear();
if (TriSet.empty() || GridCell.empty())
{
return;
}
Allocator<MeshType>::AddVertices(m,GridCell.size());
typename STDEXT::hash_map<HashedPoint3i,CellType>::iterator gi;
int i=0;
for(gi=GridCell.begin();gi!=GridCell.end();++gi)
{
m.vert[i].P()=(*gi).second.Pos();
if(m.vert[i].HasColor())
m.vert[i].C()=(*gi).second.Col();
(*gi).second.id=i;
++i;
}
Allocator<MeshType>::AddFaces(m,TriSet.size());
TriHashSetIterator ti;
i=0;
for(ti=TriSet.begin();ti!=TriSet.end();++ti)
{
m.face[i].V(0)=&(m.vert[(*ti).v[0]->id]);
m.face[i].V(1)=&(m.vert[(*ti).v[1]->id]);
m.face[i].V(2)=&(m.vert[(*ti).v[2]->id]);
// if we are merging faces even when opposite we choose
// the best orientation according to the averaged normal
if(!DuplicateFaceParam)
{
CoordType N=vcg::Normal(m.face[i]);
int badOrient=0;
if( N*(*ti).v[0]->n <0) ++badOrient;
if( N*(*ti).v[1]->n <0) ++badOrient;
if( N*(*ti).v[2]->n <0) ++badOrient;
if(badOrient>2)
std::swap(m.face[i].V(0),m.face[i].V(1));
}
i++;
}
}
}; //end class clustering
} // namespace tri
} // namespace vcg
#endif