vcglib/vcg/simplex/face/pos.h

346 lines
9.7 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. *
* *
* 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 1.4 2004/05/10 15:21:47 cignoni
Added a constructor without vertex pointer
Revision 1.3 2004/05/10 13:41:57 cignoni
Added VFIterator
Revision 1.2 2004/03/12 15:22:28 cignoni
Written some documentation and added to the trimes doxygen module
Revision 1.1 2004/03/10 08:32:30 cignoni
Initial commit
****************************************************************************/
/** \file pos.h
* Definition of vcg:face::Pos class.
* This file contain the definition of vcg::face::Pos class and the derived vcg::face::PosN class.
*/
#ifndef __VCG_FACE_POS
#define __VCG_FACE_POS
namespace vcg {
namespace face {
/** \addtogroup face */
/*@{*/
/** Templated over the class face, it stores a \em position over a face in a mesh.
It contain a pointer to the current face,
the index of one edge and a edge's incident vertex.
*/
template <typename FaceType>
class Pos
{
public:
/// The vertex type
typedef typename FaceType::VertexType VertexType;
typedef typename FaceType::BaseFaceType BaseFaceType;
///The HEdgePos type
typedef Pos<FaceType> BasePosType;
/// The vector type
typedef typename VertexType::CoordType CoordType;
/// The scalar type
typedef typename VertexType::ScalarType ScalarType;
/// Pointer to the face of the half-edge
typename FaceType::BaseFaceType *f;
/// Index of the edge
int z;
/// Pointer to the vertex
VertexType *v;
/// Default constructor
Pos(){}
/// Constructor which associates the half-edge elementet with a face, its edge and its vertex
Pos(BaseFaceType * const fp, int const zp, VertexType * const vp){f=fp; z=zp; v=vp;}
Pos(BaseFaceType * const fp, int const zp){f=fp; z=zp; v=f.V[zp];}
/// Operator to compare two half-edge
inline bool operator == ( BasePosType const & p ) const {
return (f==p.f && z==p.z && v==p.v);
}
/// Operator to compare two half-edge
inline bool operator != ( BasePosType const & p ) const {
return (f!=p.f || z!=p.z || v!=p.v);
}
/// Operator to order half-edge; it's compare at the first the face pointers, then the index of the edge and finally the vertex pointers
inline bool operator <= ( BasePosType const & p) const {
return (f!=p.f)?(f<f.p):
(z!=p.z)?(z<p.z):
(v<=p.v);
}
/// Assignment operator
inline BasePosType & operator = ( const BasePosType & h ){
f=h.f;
z=h.z;
v=h.v;
return *this;
}
/// Set to null the half-edge
void SetNull(){
f=0;
v=0;
z=-1;
}
/// Check if the half-edge is null
bool IsNull() const {
return f==0 || v==0 || z<0;
}
//Cambia Faccia lungo z
// e' uguale a FlipF solo che funziona anche per non manifold.
/// Change face via z
void NextF()
{
FaceType * t = f;
f = t->FFp(z);
z = t->FFi(z);
}
// Paolo Cignoni 19/6/99
// Si muove sulla faccia adiacente a f, lungo uno spigolo che
// NON e' j, e che e' adiacente a v
// in questo modo si scandiscono tutte le facce incidenti in un
// vertice f facendo Next() finche' non si ritorna all'inizio
// Nota che sul bordo rimbalza, cioe' se lo spigolo !=j e' di bordo
// restituisce sempre la faccia f ma con nj che e' il nuovo spigolo di bordo
// vecchi parametri: FaceType * & f, VertexType * v, int & j
/// It moves on the adjacent face incident to v, via a different edge that j
void NextE()
{
assert( f->V(z)==v || f->V((z+1)%3)==v ); // L'edge j deve contenere v
FlipE();
FlipF();
assert( f->V(z)==v || f->V((z+1)%3)==v );
}
// Cambia edge mantenendo la stessa faccia e lo stesso vertice
/// Changes edge maintaining the same face and the same vertex
void FlipE()
{
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
if(f->V((z+1)%3)==v) z=(z+1)%3;
else z=(z-1+3)%3;
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
}
// Cambia Faccia mantenendo lo stesso vertice e lo stesso edge
// Vale che he.flipf.flipf= he
// Se l'he e' di bordo he.flipf()==he
// Si puo' usare SOLO se l'edge e' 2manifold altrimenti
// si deve usare nextf
/// Changes face maintaining the same vertex and the same edge
void FlipF()
{
assert( f->FFp(z)->FFp(f->FFi(z))==f );
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
FaceType *nf=f->FFp(z);
int nz=f->FFi(z);
assert(nf->V((nz+2)%3)!=v && (nf->V((nz+1)%3)==v || nf->V((nz+0)%3)==v));
f=nf;
z=nz;
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
}
/// Changes vertex maintaining the same face and the same edge
void FlipV()
{
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
if(f->V((z+1)%3)==v)
v=f->V((z+0)%3);
else
v=f->V((z+1)%3);
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
}
// return the vertex that it should have if we make FlipV;
VertexType *VFlip()
{
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
if(f->V((z+1)%3)==v) return f->V((z+0)%3);
else return f->V((z+1)%3);
}
// Trova il prossimo half-edge di bordo (nhe)
// tale che
// --nhe.f adiacente per vertice a he.f
// --nhe.v adiacente per edge di bordo a he.v
// l'idea e' che se he e' un half edge di bordo
// si puo scorrere tutto un bordo facendo
//
// hei=he;
// do
// hei.Nextb()
// while(hei!=he);
/// Finds the next half-edge border
void NextB( )
{
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
assert(f->FFP(z)==f); // f is border along j
// Si deve cambiare faccia intorno allo stesso vertice v
//finche' non si trova una faccia di bordo.
do
NextE();
while(!f->IsBorder(z));
// L'edge j e' di bordo e deve contenere v
assert(f->IsBorder(z) &&( f->V(z)==v || f->V((z+1)%3)==v ));
FlipV();
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
assert(f->FFp(z)==f); // f is border along j
}
/// Checks if the half-edge is of border
bool IsBorder()
{
return f->IsBorder(z);
}
/// Return the dimension of the star
int StarSize()
{
int n=0;
BasePosType ht=*this;
bool bf=false;
do
{
++n;
ht.NextE();
if(ht.IsBorder()) bf=true;
} while(ht!=*this);
if(bf) return n/2;
else return n;
}
/** Function to inizialize an half-edge.
@param fp Puntatore alla faccia
@param zp Indice dell'edge
@param vp Puntatore al vertice
*/
void Set(BaseFaceType * const fp, int const zp, VertexType * const vp)
{
f=fp;z=zp;v=vp;
assert(f->V((z+2)%3)!=v && (f->V((z+1)%3)==v || f->V((z+0)%3)==v));
}
void Assert()
#ifdef _DEBUG
{
BasePosType ht=*this;
ht.FlipF();
ht.FlipF();
assert(ht==*this);
ht.FlipE();
ht.FlipE();
assert(ht==*this);
ht.FlipV();
ht.FlipV();
assert(ht==*this);
}
#else
{}
#endif
// Controlla la coerenza di orientamento di un hpos con la relativa faccia
/// Checks the orientation coherence of a half-edge with the face
inline bool Coerent() const
{
return v == f->V(z); // e^(ip)+1=0 ovvero E=mc^2
}
};
template <class FaceType>
/** Class PosN.
This structure is equivalent to a Pos, but it contains a normal.
@param FaceType (Template-Parameter) Specifies the type of the faces
*/
class PosN : public Pos<FaceType>
{
public:
typedef typename FaceType::CoordType CoordType;
//normale per visualizzazione creaseangle
CoordType normal;
};
/** Class VFIterator.
This class is used as an iterator over the VF adjacency.
*/
template <typename FaceType>
class VFIterator
{
public:
/// The vertex type
typedef typename FaceType::VertexType VertexType;
/// The vector type
typedef typename VertexType::CoordType CoordType;
/// The scalar type
typedef typename VertexType::ScalarType ScalarType;
/// Pointer to the face of the half-edge
typename FaceType::BaseFaceType *f;
/// Index of the edge
int z;
/// Default constructor
VFIterator(){}
/// Constructor which associates the half-edge elementet with a face, its edge and its vertex
VFIterator(VertexType * const vp){f=vp->VFb();z=vp->VFi();}
bool End() const {return f==0;}
bool operator++() {
FaceType* t = f;
f = t->VFp(z);
z = t->VFi(z);
}
};
/*@}*/
} // end namespace
} // end namespace
#endif