vcglib/vcg/complex/trimesh/geodesic.h

360 lines
11 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 1.6 2008/01/12 19:07:05 ganovelli
Recompiled from previous out of date version. Still to revise but working
Revision 1.5 2005/12/13 17:17:19 ganovelli
first importing from old version. NOT optimized! It works with VertexFace Adjacency even over non manifolds
*#**************************************************************************/
#include <assert.h>
#include <vcg/container/simple_temporary_data.h>
#include <vcg/simplex/face/pos.h>
#include <vcg/math/base.h>
#include <deque>
#include <vector>
#include <list>
#include <functional>
/*
class for computing approximated geodesic distances on a mesh.
basic example: farthest vertex from a specified one
MyMesh m;
MyMesh::VertexPointer seed,far;
MyMesh::ScalarType dist;
vcg::Geo<MyMesh> g;
g.FarthestVertex(m,seed,far,d);
*/
namespace vcg{
template <class MeshType>
class Geo{
public:
typedef typename MeshType::VertexPointer VertexPointer;
typedef typename MeshType::ScalarType ScalarType;
/* Auxiliary class for keeping the heap of vertices to visit and their estimated distance
*/
struct VertDist{
VertDist(){}
VertDist(VertexPointer _v, ScalarType _d):v(_v),d(_d){}
VertexPointer v;
ScalarType d;
};
/* Temporary data to associate to all the vertices: estimated distance and boolean flag
*/
template <class MeshType>
struct TempData{
TempData(){}
TempData(const ScalarType & d_){d=d_;visited=false;}
ScalarType d;
bool visited;
};
typedef SimpleTempData<std::vector<typename MeshType::VertexType>, TempData<MeshType> > TempDataType;
TempDataType * TD;
struct pred: public std::binary_function<VertDist,VertDist,bool>{
pred(){};
bool operator()(const VertDist& v0, const VertDist& v1) const
{return (v0.d > v1.d);}
};
/*
starting from the seeds, it assign a distance value to each vertex. The distance of a vertex is its
approximated geodesic distance to the closest seeds.
This is function is not meant to be called (although is not prevented). Instead, it is invoked by
wrapping function.
*/
typename MeshType::VertexPointer Visit(
MeshType & m,
std::vector<VertDist> & _frontier,
ScalarType & max_distance,
bool fartestOnBorder = false
)
{
bool isLeaf,toQueue;
std::vector<VertDist> frontier;
MeshType::VertexIterator ii;
std::list<typename MeshType::VertexPointer> children;
typename MeshType::VertexPointer curr,farthest,pw1;
std::list<typename MeshType::VertexPointer>::iterator is;
std::deque<typename MeshType::VertexPointer> leaves;
std::vector <std::pair<typename MeshType::VertexPointer,typename MeshType::ScalarType> > expansion;
std::vector <VertDist >::iterator ifr;
face::VFIterator<typename MeshType::FaceType> x;int k;
typename MeshType::VertexPointer pw;
//Requirements
assert(m.HasVFTopology());
assert(!_frontier.empty());
TD = new TempDataType(m.vert);
TD->Start(TempData<MeshType>(-1.0));
for(ifr = _frontier.begin(); ifr != _frontier.end(); ++ifr){
(*TD)[(*ifr).v].visited= true;
(*TD)[(*ifr).v].d = 0.0;
(*ifr).d = 0.0;
}
for(ifr = _frontier.begin(); ifr != _frontier.end(); ++ifr)
{
// determina la distanza dei vertici della fan
for( x.f = (*ifr).v->VFp(), x.z = (*ifr).v->VFi(); x.f!=0; ++x )
for(k=0;k<2;++k)
{
if(k==0) pw = x.f->V1(x.z);
else pw = x.f->V2(x.z);
if((*TD)[pw].d ==-1){
(*TD)[pw].d = Distance(pw->cP(),(*ifr).v->cP());
frontier.push_back(VertDist(pw,(*TD)[pw].d));
}
}
}
// initialize Heap
make_heap(frontier.begin(),frontier.end(),pred());
ScalarType curr_d,d_curr = 0.0;
max_distance=0.0;
std::vector<VertDist >:: iterator iv;
while(!frontier.empty())
{ //printf("size: %d\n", frontier.size());
expansion.clear();
pop_heap(frontier.begin(),frontier.end(),pred());
curr = (frontier.back()).v;
frontier.pop_back();
d_curr = (*TD)[curr].d;
(*TD)[curr].visited = true;
isLeaf = (!fartestOnBorder || curr->IsB());
face::VFIterator<typename MeshType::FaceType> x;int k;
for( x.f = curr->VFp(), x.z = curr->VFi(); x.f!=0; ++x )
for(k=0;k<2;++k)
{
if(k==0) {
pw = x.f->V1(x.z);
pw1=x.f->V2(x.z);
}
else {
pw = x.f->V2(x.z);
pw1=x.f->V1(x.z);
}
const ScalarType & d_pw1 = (*TD)[pw1].d;
if((! (*TD)[pw1].visited ) || d_curr == 0.0)
{
if( (*TD)[pw].d == -1){
curr_d = (*TD)[curr].d + (pw->P()-curr->P()).Norm();
expansion.push_back(std::pair<typename MeshType::VertexPointer,typename MeshType::ScalarType>(pw,curr_d));
}
continue;
}
assert( (*TD)[pw1].d != -1);
assert( (curr!=pw) && (pw!=pw1) && (pw1 != curr));
assert(d_pw1!=-1.0);
//************** calcolo della distanza di pw in base alle distanze note di pw1 e curr
//************** sapendo che (curr,pw,pw1) e'una faccia della mesh
//************** (vedi figura in file distance.gif)
Point3<MeshType::ScalarType> w_c = pw->cP()- curr->cP();
Point3<MeshType::ScalarType> w_w1 = pw->cP()- pw1->cP();
Point3<MeshType::ScalarType> w1_c = pw1->cP()- curr->cP();
ScalarType ew_c = (w_c).Norm();
ScalarType ew_w1 = (w_w1).Norm();
ScalarType ec_w1 = (w1_c).Norm();
ScalarType alpha,alpha_, beta,beta_,theta,h,delta,s,a,b;
alpha = acos((w_c*w1_c)/(ew_c*ec_w1));
s = (d_curr + d_pw1+ec_w1)/2;
a = s/ec_w1;
b = a*s;
alpha_ = 2*acos ( math::Min<ScalarType>(1.0,sqrt( (b- a* d_pw1)/d_curr)));
if ( alpha+alpha_ > M_PI){
curr_d = d_curr + ew_c;
}else
{
beta_ = 2*acos ( math::Min<ScalarType>(1.0,sqrt( (b- a* d_curr)/d_pw1)));
beta = acos((w_w1)*(-w1_c)/(ew_w1*ec_w1));
if ( beta+beta_ > M_PI)
curr_d = d_pw1 + ew_w1;
else
{
theta = ScalarType(M_PI)-alpha-alpha_;
delta = cos(theta)* ew_c;
h = sin(theta)* ew_c;
curr_d = sqrt( pow(h,2)+ pow(d_curr + delta,2));
}
}
//**************************************************************************************
toQueue = ( (*TD)[(pw)].d==-1);
if(toQueue){// se non e'gia' in coda ce lo mette
expansion.push_back(std::pair<typename MeshType::VertexPointer,typename MeshType::ScalarType>(pw,curr_d));
}else
{
if( (*TD)[(pw)].d > curr_d )
(*TD)[(pw)].d = curr_d;
}
if(isLeaf){
if(d_curr > max_distance){
max_distance = d_curr;
farthest = curr;
}
}
}
std::vector <std::pair<typename MeshType::VertexPointer,typename MeshType::ScalarType> > ::iterator i;
for(i = expansion.begin(); i!= expansion.end(); ++i)
{
(*TD)[(*i).first].d = (*i).second;
frontier.push_back(VertDist((*i).first,(*TD)[(*i).first].d));
push_heap(frontier.begin(),frontier.end(),pred());
} // end for
}// end while
// scrivi le distanze sul campo qualita' (nn: farlo parametrico)
MeshType::VertexIterator vi;
for(vi = m.vert.begin(); vi != m.vert.end(); ++vi)
(*vi).Q() = (*TD)[&(*vi)].d;
(*TD).Stop();
delete TD;
return farthest;
}
public:
/*
Given a mesh and a vector of pointers to vertices (sources), assigns the approximated geodesic
distance from the cloasest source to all the mesh vertices and returns the pointer to the farthest.
Note: update the field Q() of the vertices
*/
void FartestVertex( MeshType & m,
std::vector<typename MeshType::VertexPointer> & fro,
typename MeshType::VertexPointer & farthest,
ScalarType & distance){
std::vector<typename MeshType::VertexPointer>::iterator fi;
std::vector<VertDist>fr;
for( fi = fro.begin(); fi != fro.end() ; ++fi)
fr.push_back(VertDist(*fi,-1));
farthest = Visit(m,fr,distance,false);
}
/*
Given a mesh and a pointers to a vertex-source (source), assigns the approximated geodesic
distance from the vertex-source to all the mesh vertices and returns the pointer to the farthest
Note: update the field Q() of the vertices
*/
void FartestVertex( MeshType & m,
typename MeshType::VertexPointer seed,
typename MeshType::VertexPointer & farthest,
ScalarType & distance){
std::vector<typename MeshType::VertexPointer> fro;
fro.push_back( seed );
typename MeshType::VertexPointer v0;
FartestVertex(m,fro,v0,distance);
farthest = v0;
}
/*
Same as FartestPoint but the returned pointer is to a border vertex
Note: update the field Q() of the vertices
*/
void FartestBVertex(MeshType & m,
std::vector<typename MeshType::VertexPointer> & fro,
typename MeshType::VertexPointer & farthest,
ScalarType & distance){
std::vector<typename MeshType::VertexPointer>::iterator fi;
std::vector<VertDist>fr;
for( fi = fro.begin(); fi != fro.end() ; ++fi)
fr.push_back(VertDist(*fi,-1));
farthest = Visit(m,fr,distance,true);
}
/*
Same as FartestPoint but the returned pointer is to a border vertex
Note: update the field Q() of the vertices
*/
void FartestBVertex( MeshType & m,
typename MeshType::VertexPointer seed,
typename MeshType::VertexPointer & farthest,
ScalarType & distance){
std::vector<typename MeshType::VertexPointer> fro;
fro.push_back( seed );
typename MeshType::VertexPointer v0;
FartestBVertex(m,fro,v0,distance);
farthest = v0;
}
/*
Assigns to each vertex of the mesh its distance to the closest vertex on the border
Note: update the field Q() of the vertices
*/
void DistanceFromBorder( MeshType & m,
typename MeshType::VertexPointer & v0,
ScalarType & distance
){
std::vector<typename MeshType::VertexPointer> fro;
MeshType::VertexIterator vi;
MeshType::VertexPointer farthest;
for(vi = m.vert.begin(); vi != m.vert.end(); ++vi)
if( (*vi).IsB())
fro.push_back(&(*vi));
FartestVertex(m,fro,farthest,distance);
}
};
};// end namespace