// Build the mass matrix (for these variables) scaled by c_a, storing
// it in 'storage' sparse matrix, at given column/row offset.
// Note, most iterative solvers don't need to know mass matrix explicitly.
// Optimized: doesn't fill unneeded elements except mass and 3x3 inertia.
void ChVariablesBodySharedMass::Build_M(ChSparseMatrix& storage, int insrow, int inscol, const double c_a) {
storage.SetElement(insrow + 0, inscol + 0, c_a * sharedmass->mass);
storage.SetElement(insrow + 1, inscol + 1, c_a * sharedmass->mass);
storage.SetElement(insrow + 2, inscol + 2, c_a * sharedmass->mass);
ChMatrix33<> scaledJ = sharedmass->inertia * c_a;
storage.PasteMatrix(scaledJ, insrow + 3, inscol + 3);
}
int ChSparseMatrix::DecomposeAndSolve_LDL_forLCP(ChMatrix<>* B, ChMatrix<>* X, double& mdet,
int i_D, int i_C, int n_unilaterals,
ChUnilateralData constr_data[], int from_eq)
{
ChSparseMatrix tempM;
tempM.CopyFromMatrix(this);
// deactivate the non-clamped or not yet considered unilateral constraints
for (int nd = 0; nd < n_unilaterals; nd++)
{
if (constr_data[nd].status != CONSTR_UNILATERAL_ON)
tempM.SetElement(i_D+nd, i_D+nd, INFINITE_PIVOT);
}
tempM.DecomposeAndSolve_LDL(B,X,mdet, from_eq);
return TRUE;
}
// Build the mass matrix (for these variables) scaled by c_a, storing
// it in 'storage' sparse matrix, at given column/row offset.
// Note, most iterative solvers don't need to know mass matrix explicitly.
// Optimized: doesn't fill unneeded elements except mass.
void ChVariablesShaft::Build_M(ChSparseMatrix& storage, int insrow, int inscol, const double c_a) {
storage.SetElement(insrow + 0, inscol + 0, c_a * m_inertia);
}
// Build the mass matrix (for these variables) scaled by c_a, storing
// it in 'storage' sparse matrix, at given column/row offset.
// Note, most iterative solvers don't need to know mass matrix explicitly.
// Optimized: doesn't fill unneeded elements except mass.
void ChVariablesNode::Build_M(ChSparseMatrix& storage, int insrow, int inscol, const double c_a) {
double scaledmass = c_a * mass;
storage.SetElement(insrow + 0, inscol + 0, scaledmass);
storage.SetElement(insrow + 1, inscol + 1, scaledmass);
storage.SetElement(insrow + 2, inscol + 2, scaledmass);
}
