Method BuildRedistributeMask

Src/Particle/AMReX_ParticleContainerBase.cpp:332–385

}

void ParticleContainerBase::BuildRedistributeMask (int lev, int nghost) const
{
    BL_PROFILE("ParticleContainer::BuildRedistributeMask");
    AMREX_ASSERT(lev == 0);

    if (redistribute_mask_ptr == nullptr ||
        redistribute_mask_nghost < nghost ||
        ! BoxArray::SameRefs(redistribute_mask_ptr->boxArray(), this->ParticleBoxArray(lev)) ||
        ! DistributionMapping::SameRefs(redistribute_mask_ptr->DistributionMap(), this->ParticleDistributionMap(lev)))
    {
        const Geometry& geom = this->Geom(lev);
        const BoxArray& ba = this->ParticleBoxArray(lev);
        const DistributionMapping& dmap = this->ParticleDistributionMap(lev);

        redistribute_mask_nghost = nghost;
        redistribute_mask_ptr = std::make_unique<iMultiFab>(ba, dmap, 2, nghost);
        redistribute_mask_ptr->setVal(-1, nghost);

        const auto tile_size_do = amrex::ParticleContainerBase::do_tiling ? amrex::ParticleContainerBase::tile_size : IntVect::TheZeroVector();

#ifdef AMREX_USE_OMP
#pragma omp parallel
#endif
        for (MFIter mfi(*redistribute_mask_ptr, tile_size_do); mfi.isValid(); ++mfi)
        {
            const Box& box = mfi.tilebox();
            const int grid_id = mfi.index();
            const int tile_id = mfi.LocalTileIndex();
            (*redistribute_mask_ptr)[mfi].template setVal<RunOn::Host>(grid_id, box, 0, 1);
            (*redistribute_mask_ptr)[mfi].template setVal<RunOn::Host>(tile_id, box, 1, 1);
        }

        redistribute_mask_ptr->FillBoundary(geom.periodicity());

        neighbor_procs.clear();
        for (MFIter mfi(*redistribute_mask_ptr, tile_size_do); mfi.isValid(); ++mfi)
        {
            const Box& box = mfi.growntilebox();
            for (IntVect iv = box.smallEnd(); iv <= box.bigEnd(); box.next(iv))
            {
                const int grid = (*redistribute_mask_ptr)[mfi](iv, 0);
                if (grid >= 0)
                {
                    const int global_rank = this->ParticleDistributionMap(lev)[grid];
                    const int rank = ParallelContext::global_to_local_rank(global_rank);
                    if (rank != ParallelContext::MyProcSub()) {
                        neighbor_procs.push_back(rank);
                    }
                }
            }
        }
        RemoveDuplicates(neighbor_procs);
    }
}

}