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/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2004-2016 \/)\/ *
* 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 MESH_TO_MATRIX
#define MESH_TO_MATRIX
#include <vcg/complex/complex.h>
#include <vcg/complex/algorithms/update/topology.h>
#include <vcg/complex/algorithms/update/quality.h>
#include <vcg/complex/algorithms/harmonic.h>
namespace vcg {
namespace tri {
template < typename MeshType >
class MeshToMatrix
{
// define types
typedef typename MeshType::FaceType FaceType;
typedef typename MeshType::FaceIterator FaceIterator;
typedef typename MeshType::VertexType VertexType;
typedef typename MeshType::VertexIterator VertexIterator;
typedef typename MeshType::CoordType CoordType;
typedef typename MeshType::ScalarType ScalarType;
typedef typename Eigen::Matrix<ScalarType, Eigen::Dynamic, Eigen::Dynamic> MatrixXm;
static void GetTriEdgeAdjacency(const MatrixXm& V,
const Eigen::MatrixXi& F,
Eigen::MatrixXi& EV,
Eigen::MatrixXi& FE,
Eigen::MatrixXi& EF)
{
(void)V;
//assert(igl::is_manifold(V,F));
std::vector<std::vector<int> > ETT;
for(int f=0;f<F.rows();++f)
for (int i=0;i<3;++i)
{
// v1 v2 f vi
int v1 = F(f,i);
int v2 = F(f,(i+1)%3);
if (v1 > v2) std::swap(v1,v2);
std::vector<int> r(4);
r[0] = v1; r[1] = v2;
r[2] = f; r[3] = i;
ETT.push_back(r);
}
std::sort(ETT.begin(),ETT.end());
// count the number of edges (assume manifoldness)
int En = 1; // the last is always counted
for(unsigned i=0;i<ETT.size()-1;++i)
if (!((ETT[i][0] == ETT[i+1][0]) && (ETT[i][1] == ETT[i+1][1])))
++En;
EV = Eigen::MatrixXi::Constant((int)(En),2,-1);
FE = Eigen::MatrixXi::Constant((int)(F.rows()),3,-1);
EF = Eigen::MatrixXi::Constant((int)(En),2,-1);
En = 0;
for(unsigned i=0;i<ETT.size();++i)
{
if (i == ETT.size()-1 ||
!((ETT[i][0] == ETT[i+1][0]) && (ETT[i][1] == ETT[i+1][1]))
)
{
// Border edge
std::vector<int>& r1 = ETT[i];
EV(En,0) = r1[0];
EV(En,1) = r1[1];
EF(En,0) = r1[2];
FE(r1[2],r1[3]) = En;
}
else
{
std::vector<int>& r1 = ETT[i];
std::vector<int>& r2 = ETT[i+1];
EV(En,0) = r1[0];
EV(En,1) = r1[1];
EF(En,0) = r1[2];
EF(En,1) = r2[2];
FE(r1[2],r1[3]) = En;
FE(r2[2],r2[3]) = En;
++i; // skip the next one
}
++En;
}
// Sort the relation EF, accordingly to EV
// the first one is the face on the left of the edge
for(unsigned i=0; i<EF.rows(); ++i)
{
int fid = EF(i,0);
bool flip = true;
// search for edge EV.row(i)
for (unsigned j=0; j<3; ++j)
{
if ((F(fid,j) == EV(i,0)) && (F(fid,(j+1)%3) == EV(i,1)))
flip = false;
}
if (flip)
{
int tmp = EF(i,0);
EF(i,0) = EF(i,1);
EF(i,1) = tmp;
}
}
}
public:
// return mesh as vector of vertices and faces
static void GetTriMeshData(const MeshType &mesh,
Eigen::MatrixXi &faces,
MatrixXm &vert)
{
tri::RequireCompactness(mesh);
// create eigen matrix of vertices
vert=MatrixXm(mesh.VN(), 3);
// copy vertices
for (int i = 0; i < mesh.VN(); i++)
for (int j = 0; j < 3; j++)
vert(i,j) = mesh.vert[i].cP()[j];
// create eigen matrix of faces
faces=Eigen::MatrixXi(mesh.FN(), 3);
// copy faces
for (int i = 0; i < mesh.FN(); i++)
for (int j = 0; j < 3; j++)
faces(i,j) = (int)tri::Index(mesh,mesh.face[i].cV(j));
}
// return normals of the mesh
static void GetNormalData(const MeshType &mesh,
MatrixXm &Nvert,
MatrixXm &Nface)
{
// create eigen matrix of vertices
Nvert=MatrixXm(mesh.VN(), 3);
Nface=MatrixXm(mesh.FN(), 3);
// per vertices normals
for (int i = 0; i < mesh.VN(); i++)
for (int j = 0; j < 3; j++)
Nvert(i,j) = mesh.vert[i].cN()[j];
// per vertices normals
for (int i = 0; i < mesh.FN(); i++)
for (int j = 0; j < 3; j++)
Nface(i,j) = mesh.face[i].cN()[j];
}
// get face to face adjacency
static void GetTriFFAdjacency(MeshType &mesh,
Eigen::MatrixXi &FFp,
Eigen::MatrixXi &FFi)
{
tri::UpdateTopology<MeshType>::FaceFace(mesh);
FFp = Eigen::MatrixXi(mesh.FN(),3);
FFi = Eigen::MatrixXi(mesh.FN(),3);
for (int i = 0; i < mesh.FN(); i++)
for (int j = 0; j < 3; j++)
{
FaceType *AdjF=mesh.face[i].FFp(j);
if (AdjF==&mesh.face[i])
{
FFp(i,j)=-1;
FFi(i,j)=-1;
}
else
{
FFp(i,j)=tri::Index(mesh,AdjF);
FFi(i,j)=mesh.face[i].FFi(j);
}
}
}
static void GetUVData(const MeshType &mesh,
MatrixXm & uv)
{
tri::RequireVertexCompactness(mesh);
tri::RequirePerVertexTexCoord(mesh);
uv = MatrixXm(mesh.VN(), 2);
// per vertices uv
for (int i = 0; i < mesh.VN(); i++)
{
uv(i,0) = mesh.vert[i].cT().U();
uv(i,1) = mesh.vert[i].cT().V();
}
}
// get edge to face and edge to vertex adjacency
static void GetTriEdgeAdjacency(const MeshType &mesh,
Eigen::MatrixXi& EV,
Eigen::MatrixXi& FE,
Eigen::MatrixXi& EF)
{
Eigen::MatrixXi faces;
MatrixXm vert;
GetTriMeshData(mesh,faces,vert);
GetTriEdgeAdjacency(vert,faces,EV,FE,EF);
}
static Eigen::Vector3d VectorFromCoord(CoordType v)
{
Eigen::Vector3d ret(v[0],v[1],v[2]);
return ret;
}
template< class VecType >
static void PerVertexArea(const MeshType &m, VecType &h)
{
tri::RequireCompactness(m);
h.resize(m.vn);
fill(h.begin(),h.end(),0);
for (int i = 0; i < m.FN(); ++i)
{
ScalarType a = DoubleArea(m.face[i])/6.0;
for(int j=0;j<m.face[i].VN();++j)
h[tri::Index(m,m.face[i].cV(j))] += a;
}
}
template< class VecType >
static void PerFaceArea(const MeshType &m, VecType &h)
{
tri::RequireCompactness(m);
h.resize(m.fn);
for(int i=0;i<m.fn;++i)
h[i] =DoubleArea(m.face[i])/2.0;
}
static void MassMatrixEntry(MeshType &m,
std::vector<std::pair<int,int> > &index,
std::vector<ScalarType> &entry,
bool vertexCoord=true)
{
tri::RequireCompactness(m);
typename MeshType::template PerVertexAttributeHandle<ScalarType> h =
tri::Allocator<MeshType>:: template GetPerVertexAttribute<ScalarType>(m, "area");
for(int i=0;i<m.vn;++i) h[i]=0;
for(FaceIterator fi=m.face.begin(); fi!=m.face.end();++fi)
{
ScalarType a = DoubleArea(*fi);
for(int j=0;j<fi->VN();++j)
h[tri::Index(m,fi->V(j))] += a;
}
ScalarType maxA=0;
for(int i=0;i<m.vn;++i)
maxA = max(maxA,h[i]);
//store the index and the scalar for the sparse matrix
for (size_t i=0;i<m.vert.size();i++)
{
if (vertexCoord)
{
for (size_t j=0;j<3;j++)
{
int currI=(i*3)+j;
index.push_back(std::pair<int,int>(currI,currI));
entry.push_back(h[i]/maxA);
}
}
else
{
int currI=i;
index.push_back(std::pair<int,int>(currI,currI));
entry.push_back(h[i]/maxA);
}
}
tri::Allocator<MeshType>::template DeletePerVertexAttribute<ScalarType>(m,h);
}
static void GetLaplacianEntry(MeshType &mesh,
FaceType &f,
std::vector<std::pair<int,int> > &index,
std::vector<ScalarType> &entry,
bool cotangent,
ScalarType weight = 1,
bool vertexCoord=true)
{
if (cotangent) vcg::tri::MeshAssert<MeshType>::OnlyTriFace(mesh);
for (int i=0;i<f.VN();i++)
{
if (cotangent)
{
weight=Harmonic<MeshType>::template CotangentWeight<ScalarType>(f,i);
}
//get the index of the vertices
int indexV0=Index(mesh,f.V0(i));
int indexV1=Index(mesh,f.V1(i));
if (vertexCoord)
{
//then assemble the matrix
for (int j=0;j<3;j++)
{
//multiply by 3 and add the component
int currI0=(indexV0*3)+j;
int currI1=(indexV1*3)+j;
index.push_back(std::pair<int,int>(currI0,currI0));
entry.push_back(weight);
index.push_back(std::pair<int,int>(currI0,currI1));
entry.push_back(-weight);
index.push_back(std::pair<int,int>(currI1,currI1));
entry.push_back(weight);
index.push_back(std::pair<int,int>(currI1,currI0));
entry.push_back(-weight);
}
}
else
{
int currI0=(indexV0);
int currI1=(indexV1);
index.push_back(std::pair<int,int>(currI0,currI0));
entry.push_back(weight);
index.push_back(std::pair<int,int>(currI0,currI1));
entry.push_back(-weight);
index.push_back(std::pair<int,int>(currI1,currI1));
entry.push_back(weight);
index.push_back(std::pair<int,int>(currI1,currI0));
entry.push_back(-weight);
}
}
}
static void GetLaplacianMatrix(MeshType &mesh,
std::vector<std::pair<int,int> > &index,
std::vector<ScalarType> &entry,
bool cotangent,
ScalarType weight = 1,
bool vertexCoord=true )
{
//store the index and the scalar for the sparse matrix
for (size_t i=0;i<mesh.face.size();i++)
GetLaplacianEntry(mesh,mesh.face[i],index,entry,cotangent,weight,vertexCoord);
}
};
} // end namespace tri
} // end namespace vcg
#endif // MESH_TO_MATRIX_CONVERTER
|
