/// Generates the background mesh and computes displacements of its nodes using linear elasticity
void DGhybrid::generate_backmesh_and_compute_displacements()
{
// make a list of interior points of the quadratic mesh
int ip, ipoin, ib, ilp, idim, ninpoin_q = 0, k = 0, j;
for(ipoin = 0; ipoin < mq->gnpoin(); ipoin++)
ninpoin_q += bounflag_q[ipoin];
ninpoin_q = mq->gnpoin() - ninpoin_q;
inpoints_q.setup(ninpoin_q, mq->gndim());
k = 0;
for(ipoin = 0; ipoin < mq->gnpoin(); ipoin++)
if(!bounflag_q[ipoin])
{
for(idim = 0; idim < mq->gndim(); idim++)
inpoints_q(k,idim) = mq->gcoords(ipoin,idim);
k++;
}
std::cout << "DGhybrid: generate_backmesh_and_compute_displacements(): No. of interior points to move = " << inpoints_q.rows() << std::endl;
// setup DGM and get backmesh
dgm.setup(mq->gndim(), &inpoints_q, &backpoints, &motion_b);
dgm.generateDG();
bm = dgm.getDelaunayGraph();
std::cout << "DGhybrid: Back mesh has " << bm.gnpoin() << " points, " << bm.gnelem() << " elements." << std::endl;
bm.writeGmsh2("testdg.msh");
// prepare input for linear elasticity problem
motion_b.setup(nbackp,m->gndim());
motion_b.zeros();
// cflags contains 1 if the corresponding backmesh point has a Dirichlet BC
std::vector<int> cflags(nbackp,0);
// get displacements of the boundary points of the quadratic mesh
k = 0;
for(ip = 0; ip < mq->gnpoin(); ip++)
{
if(bounflag_q[ip] == 1)
{
for(idim = 0; idim < mq->gndim(); idim++)
{
motion_b(k, idim) = b_motion_q->get(ip,idim);
cflags[k] = 1;
}
k++;
}
}
// setup and solve the elasticity equations to get displacement of the background mesh
std::cout << "Starting linelast" << std::endl;
linm.setup(&bm, lambda, mu);
linm.assembleStiffnessMatrix();
linm.assembleLoadVector();
linm.dirichletBC_points(cflags, motion_b);
amat::SpMatrix A = linm.stiffnessMatrix();
amat::Matrix<double> b = linm.loadVector();
amat::Matrix<double> xb(2*nbackp,1);
amat::Matrix<double> x(2*nbackp,1);
xb.zeros();
// TODO: add a switch to change solver
x = sparseCG_d(&A, b, xb, tol, maxiter);
for(int i = 0; i < nbackp; i++)
for(idim = 0; idim < mq->gndim(); idim++)
motion_b(i, idim) = x.get(i+idim*nbackp);
}
