Method updateSolver

source/MRMesh/MRLaplacian.cpp:179–254

}

void Laplacian::updateSolver()
{
    if ( solver_ )
        return;

    MR_TIMER;

    const auto sz = freeVerts_.count();
    if ( sz <= 0 )
        return;

    fillVectorWithSeqNums( freeVerts_, freeVert2id_ );

    assert( !fixedSharpVertices_.intersects( freeVerts_ ) );
    firstLayerFixedVerts_ = freeVerts_;
    expand( topology_, firstLayerFixedVerts_ );
    firstLayerFixedVerts_ -= fixedSharpVertices_;
    [[maybe_unused]] const auto numSmoothVerts = firstLayerFixedVerts_.count();
    firstLayerFixedVerts_ -= freeVerts_;

    std::vector< Eigen::Triplet<double> > mTriplets;
    // equations for free vertices
    int n = 0;
    for ( auto v : freeVerts_ )
    {
        assert( n == freeVert2id_[v] );
        int eqN = regionVert2id_[v];
        const auto eq = equations_[eqN];
        mTriplets.emplace_back( n, n, eq.centerCoeff );
        const auto lastElem = equations_[eqN+1].firstElem;
        for ( int ei = eq.firstElem; ei < lastElem; ++ ei )
        {
            const auto el = nonZeroElements_[ei];
            if ( freeVerts_.test( el.neiVert ) )
                mTriplets.emplace_back( n, freeVert2id_[el.neiVert], el.coeff );
        }
        ++n;
    }

    // equations for free neighbors of smooth fixed vertices
    for ( auto v : firstLayerFixedVerts_ )
    {
        int eqN = regionVert2id_[v];
        const auto eq = equations_[eqN];
        const auto lastElem = equations_[eqN+1].firstElem;
        for ( int ei = eq.firstElem; ei < lastElem; ++ ei )
        {
            const auto el = nonZeroElements_[ei];
            if ( freeVerts_.test( el.neiVert ) )
                mTriplets.emplace_back( n, freeVert2id_[el.neiVert], el.coeff );
        }
        ++n;
    }

    // equations for attractors
    for ( const auto & a : attractors_ )
    {
        const auto vs = a.p.getWeightedVerts( topology_ );