示例#1
0
文件: main.cpp 项目: schuellc/libigl
int main(int argc, char *argv[])
{
  using namespace Eigen;
  using namespace std;

  // Load a quad mesh generated by a conjugate field
  igl::readOFF(TUTORIAL_SHARED_PATH "/inspired_mesh_quads_Conjugate.off", VQC, FQC);

  // Convert it in a triangle mesh
  FQCtri.resize(2*FQC.rows(), 3);
  FQCtri <<  FQC.col(0),FQC.col(1),FQC.col(2),
             FQC.col(2),FQC.col(3),FQC.col(0);
  igl::slice( VQC, FQC.col(0).eval(), 1, PQC0);
  igl::slice( VQC, FQC.col(1).eval(), 1, PQC1);
  igl::slice( VQC, FQC.col(2).eval(), 1, PQC2);
  igl::slice( VQC, FQC.col(3).eval(), 1, PQC3);

  // Planarize it
  igl::planarize_quad_mesh(VQC, FQC, 100, 0.005, VQCplan);

  // Convert the planarized mesh to triangles
  igl::slice( VQCplan, FQC.col(0).eval(), 1, PQC0plan);
  igl::slice( VQCplan, FQC.col(1).eval(), 1, PQC1plan);
  igl::slice( VQCplan, FQC.col(2).eval(), 1, PQC2plan);
  igl::slice( VQCplan, FQC.col(3).eval(), 1, PQC3plan);

  // Launch the viewer
  igl::viewer::Viewer viewer;
  key_down(viewer,'2',0);
  viewer.data.invert_normals = true;
  viewer.data.show_lines = false;
  viewer.callback_key_down = &key_down;
  viewer.launch();
}
示例#2
0
int NuTo::Structure::ElementsCreate(int rInterpolationTypeId, const Eigen::MatrixXi& rNodeNumbers)
{
    std::vector<int> newElementIds;
    // go through the elements
    for (int iNode = 0; iNode < rNodeNumbers.cols(); ++iNode)
    {
        auto column = rNodeNumbers.col(iNode);
        std::vector<int> incidence(column.data(), column.data() + column.size());
        int newElementId = ElementCreate(rInterpolationTypeId, incidence);
        newElementIds.push_back(newElementId);
    }

    bool showTime = mShowTime;
    mShowTime = false;

    // create element group containing the new elements
    int newElementGroup = GroupCreate(eGroupId::Elements);
    for (int newElementId : newElementIds)
        GroupAddElement(newElementGroup, newElementId);

    mShowTime = showTime;
    return newElementGroup;
}
示例#3
0
IGL_INLINE bool igl::arap_dof_precomputation(
  const Eigen::MatrixXd & V, 
  const Eigen::MatrixXi & F,
  const LbsMatrixType & M,
  const Eigen::Matrix<int,Eigen::Dynamic,1> & G,
  ArapDOFData<LbsMatrixType, SSCALAR> & data)
{
  using namespace Eigen;
  typedef Matrix<SSCALAR, Dynamic, Dynamic> MatrixXS;
  // number of mesh (domain) vertices
  int n = V.rows();
  // cache problem size
  data.n = n;
  // dimension of mesh
  data.dim = V.cols();
  assert(data.dim == M.rows()/n);
  assert(data.dim*n == M.rows());
  if(data.dim == 3)
  {
    // Check if z-coordinate is all zeros
    if(V.col(2).minCoeff() == 0 && V.col(2).maxCoeff() == 0)
    {
      data.effective_dim = 2;
    }
  }else
  {
    data.effective_dim = data.dim;
  }
  // Number of handles
  data.m = M.cols()/data.dim/(data.dim+1);
  assert(data.m*data.dim*(data.dim+1) == M.cols());
  //assert(m == C.rows());

  //printf("n=%d; dim=%d; m=%d;\n",n,data.dim,data.m);

  // Build cotangent laplacian
  SparseMatrix<double> Lcot;
  //printf("cotmatrix()\n");
  cotmatrix(V,F,Lcot);
  // Discrete laplacian (should be minus matlab version)
  SparseMatrix<double> Lapl = -2.0*Lcot;
#ifdef EXTREME_VERBOSE
  cout<<"LaplIJV=["<<endl;print_ijv(Lapl,1);cout<<endl<<"];"<<
    endl<<"Lapl=sparse(LaplIJV(:,1),LaplIJV(:,2),LaplIJV(:,3),"<<
    Lapl.rows()<<","<<Lapl.cols()<<");"<<endl;
#endif

  // Get group sum scatter matrix, when applied sums all entries of the same
  // group according to G
  SparseMatrix<double> G_sum;
  if(G.size() == 0)
  {
    speye(n,G_sum);
  }else
  {
    // groups are defined per vertex, convert to per face using mode
    Eigen::Matrix<int,Eigen::Dynamic,1> GG;
    if(data.energy == ARAP_ENERGY_TYPE_ELEMENTS)
    {
      MatrixXi GF(F.rows(),F.cols());
      for(int j = 0;j<F.cols();j++)
      {
        Matrix<int,Eigen::Dynamic,1> GFj;
        slice(G,F.col(j),GFj);
        GF.col(j) = GFj;
      }
      mode<int>(GF,2,GG);
    }else
    {
      GG=G;
    }
    //printf("group_sum_matrix()\n");
    group_sum_matrix(GG,G_sum);
  }

#ifdef EXTREME_VERBOSE
  cout<<"G_sumIJV=["<<endl;print_ijv(G_sum,1);cout<<endl<<"];"<<
    endl<<"G_sum=sparse(G_sumIJV(:,1),G_sumIJV(:,2),G_sumIJV(:,3),"<<
    G_sum.rows()<<","<<G_sum.cols()<<");"<<endl;
#endif

  // Get covariance scatter matrix, when applied collects the covariance matrices
  // used to fit rotations to during optimization
  SparseMatrix<double> CSM;
  //printf("covariance_scatter_matrix()\n");
  covariance_scatter_matrix(V,F,data.energy,CSM);
#ifdef EXTREME_VERBOSE
  cout<<"CSMIJV=["<<endl;print_ijv(CSM,1);cout<<endl<<"];"<<
    endl<<"CSM=sparse(CSMIJV(:,1),CSMIJV(:,2),CSMIJV(:,3),"<<
    CSM.rows()<<","<<CSM.cols()<<");"<<endl;
#endif
  

  // Build the covariance matrix "constructor". This is a set of *scatter*
  // matrices that when multiplied on the right by column of the transformation
  // matrix entries (the degrees of freedom) L, we get a stack of dim by 1
  // covariance matrix column, with a column in the stack for each rotation
  // *group*. The output is a list of matrices because we construct each column
  // in the stack of covariance matrices with an independent matrix-vector
  // multiplication.
  //
  // We want to build S which is a stack of dim by dim covariance matrices.
  // Thus S is dim*g by dim, where dim is the number of dimensions and g is the
  // number of groups. We can precompute dim matrices CSM_M such that column i
  // in S is computed as S(:,i) = CSM_M{i} * L, where L is a column of the
  // skinning transformation matrix values. To be clear, the covariance matrix
  // for group k is then given as the dim by dim matrix pulled from the stack:
  // S((k-1)*dim + 1:dim,:)

  // Apply group sum to each dimension's block of covariance scatter matrix
  SparseMatrix<double> G_sum_dim;
  repdiag(G_sum,data.dim,G_sum_dim);
  CSM = G_sum_dim * CSM;
#ifdef EXTREME_VERBOSE
  cout<<"CSMIJV=["<<endl;print_ijv(CSM,1);cout<<endl<<"];"<<
    endl<<"CSM=sparse(CSMIJV(:,1),CSMIJV(:,2),CSMIJV(:,3),"<<
    CSM.rows()<<","<<CSM.cols()<<");"<<endl;
#endif

  //printf("CSM_M()\n");
  // Precompute CSM times M for each dimension
  data.CSM_M.resize(data.dim);
#ifdef EXTREME_VERBOSE
  cout<<"data.CSM_M = cell("<<data.dim<<",1);"<<endl;
#endif
  // span of integers from 0 to n-1
  Eigen::Matrix<int,Eigen::Dynamic,1> span_n(n);
  for(int i = 0;i<n;i++)
  {
    span_n(i) = i;
  }

  // span of integers from 0 to M.cols()-1
  Eigen::Matrix<int,Eigen::Dynamic,1> span_mlbs_cols(M.cols());
  for(int i = 0;i<M.cols();i++)
  {
    span_mlbs_cols(i) = i;
  }

  // number of groups
  int k = CSM.rows()/data.dim;
  for(int i = 0;i<data.dim;i++)
  {
    //printf("CSM_M(): Mi\n");
    LbsMatrixType M_i;
    //printf("CSM_M(): slice\n");
    slice(M,(span_n.array()+i*n).matrix(),span_mlbs_cols,M_i);
    LbsMatrixType M_i_dim;
    data.CSM_M[i].resize(k*data.dim,data.m*data.dim*(data.dim+1));
    assert(data.CSM_M[i].cols() == M.cols());
    for(int j = 0;j<data.dim;j++)
    {
      SparseMatrix<double> CSMj;
      //printf("CSM_M(): slice\n");
      slice(
        CSM,
        colon<int>(j*k,(j+1)*k-1),
        colon<int>(j*n,(j+1)*n-1),
        CSMj);
      assert(CSMj.rows() == k);
      assert(CSMj.cols() == n);
      LbsMatrixType CSMjM_i = CSMj * M_i;
      if(is_sparse(CSMjM_i))
      {
        // Convert to full
        MatrixXd CSMjM_ifull;
        //printf("CSM_M(): full\n");
        full(CSMjM_i,CSMjM_ifull);
//        printf("CSM_M[%d]: %d %d\n",i,data.CSM_M[i].rows(),data.CSM_M[i].cols());
//        printf("CSM_M[%d].block(%d*%d=%d,0,%d,%d): %d %d\n",i,j,k,CSMjM_i.rows(),CSMjM_i.cols(),
//            data.CSM_M[i].block(j*k,0,CSMjM_i.rows(),CSMjM_i.cols()).rows(),
//            data.CSM_M[i].block(j*k,0,CSMjM_i.rows(),CSMjM_i.cols()).cols());
//        printf("CSM_MjMi: %d %d\n",i,CSMjM_i.rows(),CSMjM_i.cols());
//        printf("CSM_MjM_ifull: %d %d\n",i,CSMjM_ifull.rows(),CSMjM_ifull.cols());
        data.CSM_M[i].block(j*k,0,CSMjM_i.rows(),CSMjM_i.cols()) = CSMjM_ifull;
      }else
      {
        data.CSM_M[i].block(j*k,0,CSMjM_i.rows(),CSMjM_i.cols()) = CSMjM_i;
      }
    }
#ifdef EXTREME_VERBOSE
    cout<<"CSM_Mi=["<<endl<<data.CSM_M[i]<<endl<<"];"<<endl;
#endif
  }

  // precompute arap_rhs matrix
  //printf("arap_rhs()\n");
  SparseMatrix<double> K;
  arap_rhs(V,F,V.cols(),data.energy,K);
//#ifdef EXTREME_VERBOSE
//  cout<<"KIJV=["<<endl;print_ijv(K,1);cout<<endl<<"];"<<
//    endl<<"K=sparse(KIJV(:,1),KIJV(:,2),KIJV(:,3),"<<
//    K.rows()<<","<<K.cols()<<");"<<endl;
//#endif
  // Precompute left muliplication by M and right multiplication by G_sum
  SparseMatrix<double> G_sumT = G_sum.transpose();
  SparseMatrix<double> G_sumT_dim_dim;
  repdiag(G_sumT,data.dim*data.dim,G_sumT_dim_dim);
  LbsMatrixType MT = M.transpose();
  // If this is a bottle neck then consider reordering matrix multiplication
  data.M_KG = -4.0 * (MT * (K * G_sumT_dim_dim));
//#ifdef EXTREME_VERBOSE
//  cout<<"data.M_KGIJV=["<<endl;print_ijv(data.M_KG,1);cout<<endl<<"];"<<
//    endl<<"data.M_KG=sparse(data.M_KGIJV(:,1),data.M_KGIJV(:,2),data.M_KGIJV(:,3),"<<
//    data.M_KG.rows()<<","<<data.M_KG.cols()<<");"<<endl;
//#endif

  // Precompute system matrix
  //printf("A()\n");
  SparseMatrix<double> A;
  repdiag(Lapl,data.dim,A);
  data.Q = MT * (A * M);
//#ifdef EXTREME_VERBOSE
//  cout<<"QIJV=["<<endl;print_ijv(data.Q,1);cout<<endl<<"];"<<
//    endl<<"Q=sparse(QIJV(:,1),QIJV(:,2),QIJV(:,3),"<<
//    data.Q.rows()<<","<<data.Q.cols()<<");"<<endl;
//#endif

  // Always do dynamics precomputation so we can hot-switch
  //if(data.with_dynamics)
  //{
    // Build cotangent laplacian
    SparseMatrix<double> Mass;
    //printf("massmatrix()\n");
    massmatrix(V,F,(F.cols()>3?MASSMATRIX_TYPE_BARYCENTRIC:MASSMATRIX_TYPE_VORONOI),Mass);
    //cout<<"MIJV=["<<endl;print_ijv(Mass,1);cout<<endl<<"];"<<
    //  endl<<"M=sparse(MIJV(:,1),MIJV(:,2),MIJV(:,3),"<<
    //  Mass.rows()<<","<<Mass.cols()<<");"<<endl;
    //speye(data.n,Mass);
    SparseMatrix<double> Mass_rep;
    repdiag(Mass,data.dim,Mass_rep);

    // Multiply either side by weights matrix (should be dense)
    data.Mass_tilde = MT * Mass_rep * M;
    MatrixXd ones(data.dim*data.n,data.dim);
    for(int i = 0;i<data.n;i++)
    {
      for(int d = 0;d<data.dim;d++)
      {
        ones(i+d*data.n,d) = 1;
      }
    }
    data.fgrav = MT * (Mass_rep * ones);
    data.fext = MatrixXS::Zero(MT.rows(),1);
    //data.fgrav = MT * (ones);
  //}


  // This may/should be superfluous
  //printf("is_symmetric()\n");
  if(!is_symmetric(data.Q))
  {
    //printf("Fixing symmetry...\n");
    // "Fix" symmetry
    LbsMatrixType QT = data.Q.transpose();
    LbsMatrixType Q_copy = data.Q;
    data.Q = 0.5*(Q_copy+QT);
    // Check that ^^^ this really worked. It doesn't always
    //assert(is_symmetric(*Q));
  }

  //printf("arap_dof_precomputation() succeeded... so far...\n");
  verbose("Number of handles: %i\n", data.m);
  return true;
}