void BaseMultiEdge<D, E>::constructQuadraticForm()
{
const InformationType& omega = _information;
Matrix<double, D, 1> omega_r = - omega * _error;
for (size_t i = 0; i < _vertices.size(); ++i) {
OptimizableGraph::Vertex* from = static_cast<OptimizableGraph::Vertex*>(_vertices[i]);
bool istatus = !(from->fixed());
if (istatus) {
const MatrixXd& A = _jacobianOplus[i];
MatrixXd AtO = A.transpose() * omega;
int fromDim = from->dimension();
Map<MatrixXd> fromMap(from->hessianData(), fromDim, fromDim);
Map<VectorXd> fromB(from->bData(), fromDim);
// ii block in the hessian
#ifdef G2O_OPENMP
from->lockQuadraticForm();
#endif
fromMap.noalias() += AtO * A;
fromB.noalias() += A.transpose() * omega_r;
// compute the off-diagonal blocks ij for all j
for (size_t j = i+1; j < _vertices.size(); ++j) {
OptimizableGraph::Vertex* to = static_cast<OptimizableGraph::Vertex*>(_vertices[j]);
#ifdef G2O_OPENMP
to->lockQuadraticForm();
#endif
bool jstatus = !(to->fixed());
if (jstatus) {
const MatrixXd& B = _jacobianOplus[j];
int idx = computeUpperTriangleIndex(i, j);
assert(idx < (int)_hessian.size());
HessianHelper& hhelper = _hessian[idx];
if (hhelper.transposed) { // we have to write to the block as transposed
hhelper.matrix.noalias() += B.transpose() * AtO.transpose();
} else {
hhelper.matrix.noalias() += AtO * B;
}
}
#ifdef G2O_OPENMP
to->unlockQuadraticForm();
#endif
}
#ifdef G2O_OPENMP
from->unlockQuadraticForm();
#endif
}
}
}
void BaseMultiEdge<D, E>::linearizeOplus()
{
#ifdef G2O_OPENMP
for (size_t i = 0; i < _vertices.size(); ++i) {
OptimizableGraph::Vertex* v = static_cast<OptimizableGraph::Vertex*>(_vertices[i]);
v->lockQuadraticForm();
}
#endif
const double delta = 1e-9;
const double scalar = 1.0 / (2*delta);
ErrorVector errorBak;
ErrorVector errorBeforeNumeric = _error;
for (size_t i = 0; i < _vertices.size(); ++i) {
//Xi - estimate the jacobian numerically
OptimizableGraph::Vertex* vi = static_cast<OptimizableGraph::Vertex*>(_vertices[i]);
if (vi->fixed())
continue;
const int vi_dim = vi->dimension();
#ifdef _MSC_VER
double* add_vi = new double[vi_dim];
#else
double add_vi[vi_dim];
#endif
std::fill(add_vi, add_vi + vi_dim, 0.0);
if (_jacobianOplus[i].rows() != _dimension || _jacobianOplus[i].cols() != vi_dim)
_jacobianOplus[i].resize(_dimension, vi_dim);
// add small step along the unit vector in each dimension
for (int d = 0; d < vi_dim; ++d) {
vi->push();
add_vi[d] = delta;
vi->oplus(add_vi);
computeError();
errorBak = _error;
vi->pop();
vi->push();
add_vi[d] = -delta;
vi->oplus(add_vi);
computeError();
errorBak -= _error;
vi->pop();
add_vi[d] = 0.0;
_jacobianOplus[i].col(d) = scalar * errorBak;
} // end dimension
#ifdef _MSC_VER
delete[] add_vi;
#endif
}
_error = errorBeforeNumeric;
#ifdef G2O_OPENMP
for (int i = (int)(_vertices.size()) - 1; i >= 0; --i) {
OptimizableGraph::Vertex* v = static_cast<OptimizableGraph::Vertex*>(_vertices[i]);
v->unlockQuadraticForm();
}
#endif
}
