/****************************************************************************
* 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. *
* *
****************************************************************************/
#ifndef __VCGLIB_POLYGON_SUPPORT
#define __VCGLIB_POLYGON_SUPPORT
#include <vector>
#include <vcg/complex/trimesh/subset.h>
#include <vcg/simplex/face/jumping_pos.h>
#include <vcg/space/planar_polygon_tessellation.h>
namespace vcg
{
namespace tri{
/// \ingroup trimesh
/// \headerfile polygon_support.h vcg/complex/trimesh/polygon_support.h
/// \brief This class is used convert between polygonal meshes and triangular meshes
/**
This class contains two members that allow to build a triangular mesh from a polygonal mesh
and viceversa. In a trimesh, the generic polygons with n sides are codified represented by tagging the internal edge of the face
with the SetF.
*/
template <class TriMeshType,class PolyMeshType >
struct PolygonSupport{
/**
Import a trianglemesh from a polygon mesh
**/
static void ImportFromPolyMesh(TriMeshType & tm, PolyMeshType & pm){
std::vector<typename PolyMeshType::CoordType> points;
std::vector<int> faces;
// the vertices are the same, simply import them
typename PolyMeshType::VertexIterator vi;
typename TriMeshType::FaceIterator tfi,tfib ;
typename TriMeshType ::VertexIterator tvi = Allocator<TriMeshType>::AddVertices(tm,pm.vert.size());
int cnt = 0;
for(tvi = tm.vert.begin(),vi = pm.vert.begin(); tvi != tm.vert.end(); ++tvi,++vi,++cnt)
if(!(*vi).IsD()) (*tvi).ImportLocal(*vi); else vcg::tri::Allocator<TriMeshType>::DeleteVertex(tm,(*tvi));
typename PolyMeshType::FaceIterator fi;
for(fi = pm.face.begin(); fi != pm.face.end(); ++fi)
if(!((*fi).IsD())){
points.clear();
for(int i = 0; i < (*fi).VN(); ++i) {
typename PolyMeshType::VertexType * v = (*fi).V(i);
points.push_back(v->P());
}
faces.clear();
TessellatePlanarPolygon3(points,faces);
tfib = tfi = Allocator<TriMeshType>::AddFaces(tm,faces.size()/3);
for(int i = 0; tfi != tm.face.end();++tfi){
(*tfi).V(0) = &tm.vert[ (*fi).V( faces[i] ) - &(*pm.vert.begin())];
(*tfi).V(1) = &tm.vert[ (*fi).V( faces[i+1]) - &(*pm.vert.begin())];
(*tfi).V(2) = &tm.vert[ (*fi).V( faces[i+2]) - &(*pm.vert.begin())];
// set the F flags
if( (faces[i]+1)%points.size() != faces[i+1]) (*tfi).SetF(0);
if( (faces[i+1]+1)%points.size() != faces[i+2]) (*tfi).SetF(1);
if( (faces[i+2]+1)%points.size() != faces[i]) (*tfi).SetF(2);
i+=3;
}
}
}
/**
Import a polygon mesh from a triangle mesh
**/
static void ImportFromTriMesh( PolyMeshType & pm, TriMeshType & tm){
// the vertices are the same, simply import them
int cnt = 0;
typename TriMeshType ::ConstVertexIterator tvi;
typename PolyMeshType::VertexIterator vi = vcg::tri::Allocator<PolyMeshType>::AddVertices(pm,tm.vert.size());
for(tvi = tm.vert.begin(); tvi != tm.vert.end(); ++tvi,++vi,++cnt)
if(!(*tvi).IsD())(*vi).ImportLocal(*tvi); else vcg::tri::Allocator<PolyMeshType> ::DeleteVertex(pm,(*vi));
// convert the faces
typename TriMeshType::FaceIterator tfi;
vcg::face::JumpingPos<typename TriMeshType::FaceType> p;
for( tfi = tm.face.begin(); tfi != tm.face.end(); ++tfi) if(!(*tfi).IsD() && !(*tfi).IsV())
{
std::vector<typename TriMeshType::VertexPointer> vs;// vertices of the polygon
std::vector<typename TriMeshType::FacePointer> fs;// triangle faces corresponding to the polygon
// find a non tagged edge
int se = 0;
for(;se < 3;++se) if (!(*tfi).IsF(se)) break;
// initialize a pos on the first non tagged edge
typename TriMeshType::VertexPointer v0 = (*tfi).V(se);
p.F() = &(*tfi);
p.E() = se;
p.V() = p.F()->V(p.F()->Next(se));
p.FlipE();
vs.push_back(p.F()->V(se));
do{
while(p.F()->IsF(p.E())) { fs.push_back(p.F()); p.FlipF(); p.FlipE(); p.F()->SetV();}
vs.push_back(p.F()->V(p.E()));
p.FlipV();
p.FlipE();
} while( p.V() != v0 );
//now vs contains all the vertices of the polygon (still in the trimesh)
typename PolyMeshType::FaceIterator pfi = vcg::tri::Allocator<PolyMeshType>::AddFaces(pm,1);
(*pfi).Alloc(vs.size());
for( int i = 0 ; i < vs.size(); ++i)
(*pfi).V(i) = ( typename PolyMeshType::VertexType*) & pm.vert[vs[i]-&(*tm.vert.begin())];
// here handle the other compoenents of the face (how the conponents of the n triangle faces goes in the
// the property of the polygon (e.g. the normal, the color, the quality and so on)
// TODO
}
}
static void ExtractPolygon(typename TriMeshType::FacePointer tfi, std::vector<typename TriMeshType::VertexPointer> &vs){
vs.clear();
// find a non tagged edge
int se = -1;
for(int i=0; i<3; i++) if (!( tfi->IsF(i))) { se = i; break;}
assert(se!=-1); // else, all faux edges!
// initialize a pos on the first non faux edge
typename TriMeshType::VertexPointer v0 = tfi->V(se);
vcg::face::JumpingPos<typename TriMeshType::FaceType> p;
p.F() = tfi;
p.E() = se;
p.V() = p.F()->V(p.F()->Next(se));
p.FlipE();
vs.push_back(p.F()->V(se));
int guard = 0;
do{
while(p.F()->IsF(p.E())) { p.FlipF(); p.FlipE(); p.F()->SetV(); if (guard++>10) break;}
if (guard++>10) break;
vs.push_back(p.F()->V(p.E()));
p.FlipV();
p.FlipE();
} while( p.V() != v0 );
}
}; // end of struct
}} // end namespace vcg::tri
#endif // __VCGLIB_TRI_CLIP