Files
igl/external/lim/Dirichlet_LIMSolver3D.cpp
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2014-06-30 11:47:27 +02:00

96 lines
2.7 KiB
C++

// Copyright 2013 - Christian Schüller 2013, schuellc@inf.ethz.ch
// Interactive Geometry Lab - ETH Zurich
#include "Dirichlet_LIMSolver3D.h"
#include "TetrahedronMesh.h"
#define IGL_HEADER_ONLY
#include "igl/adjacency_matrix.h"
#include "igl/cotmatrix.h"
#include "igl/massmatrix.h"
Dirichlet_LIMSolver3D::Dirichlet_LIMSolver3D()
{
}
Dirichlet_LIMSolver3D::~Dirichlet_LIMSolver3D()
{
}
void Dirichlet_LIMSolver3D::debugOutput(std::stringstream& info)
{
std::cout << "LP:" << info.str() << "\n";
}
void Dirichlet_LIMSolver3D::prepareProblemData(std::vector<int>& hessRowIdx, std::vector<int>& hessColIdx)
{
const int numNodes = mesh->InitalVertices->rows();
const int numTets = mesh->Tetrahedra->rows();
Eigen::SparseMatrix<double> tempL;
Eigen::SparseMatrix<double> M;
igl::massmatrix(*mesh->InitalVertices,*mesh->Tetrahedra,igl::MASSMATRIX_TYPE_BARYCENTRIC, M);
igl::cotmatrix(*mesh->InitalVertices, *mesh->Tetrahedra,tempL);
tempL *= -1;
// Create L matrix
L.resize(numVariables,numVariables);
std::vector<Eigen::Triplet<double> > triplets;
for (int k=0;k<tempL.outerSize();++k)
{
for (Eigen::SparseMatrix<double>::InnerIterator it(tempL,k);it;++it)
{
int row = 3*it.row();
int col = 3*it.col();
triplets.push_back(Eigen::Triplet<double>(row,col,it.value()));
triplets.push_back(Eigen::Triplet<double>(row+1,col+1,it.value()));
triplets.push_back(Eigen::Triplet<double>(row+2,col+2,it.value()));
}
}
L.setFromTriplets(triplets.begin(), triplets.end());
TetrahedronVertexIdx.resize(12,mesh->Tetrahedra->rows());
for (int k=0;k<L.outerSize();++k)
{
for (Eigen::SparseMatrix<double>::InnerIterator it(L,k);it;++it)
{
int row = it.row();
int col = it.col();
// std::sort for upper triangule matrix
if(row <= col)
{
hessRowIdx.push_back(row);
hessColIdx.push_back(col);
}
}
}
}
double Dirichlet_LIMSolver3D::computeFunction(const Eigen::Matrix<double,Eigen::Dynamic,1>& x)
{
// laplacian energy function f(v) = (v-p)'L(v-p)
Eigen::VectorXd vv0 = x-initialNodes;
return Divider * 0.5 * vv0.transpose() * L * vv0;
}
void Dirichlet_LIMSolver3D::computeGradient(const Eigen::Matrix<double,Eigen::Dynamic,1>& x, Eigen::Matrix<double,Eigen::Dynamic,1>& grad)
{
// laplacian
grad = L * (x-initialNodes) * Divider;
}
void Dirichlet_LIMSolver3D::computeHessian(const Eigen::Matrix<double,Eigen::Dynamic,1>& x, const Eigen::Matrix<double*,Eigen::Dynamic,1>& hess)
{
// laplacian
int numElem = 0;
for (int k=0;k<L.outerSize();++k)
{
for (Eigen::SparseMatrix<double>::InnerIterator it(L,k);it;++it)
{
if(it.row() <= it.col())
*hess[numElem++] = it.value() * Divider;
}
}
}