cell_linked_list.hpp

#pragma once

#include "base_particles.h"
#include "cell_linked_list.h"

namespace SPH
{
    //=================================================================================================//
    template<typename GetParticleIndex, typename GetSearchDepth, typename GetNeighborRelation>
    void CellLinkedList::searchNeighborsByParticles(size_t total_real_particles, BaseParticles& source_particles, 
        ParticleConfiguration& particle_configuration, GetParticleIndex& get_particle_index, 
        GetSearchDepth& get_search_depth, GetNeighborRelation& get_neighbor_relation)
    {
        parallel_for(blocked_range<size_t>(0, total_real_particles),
            [&](const blocked_range<size_t>& r) {
                StdLargeVec<Vecd>& pos_n = source_particles.pos_;
                for (size_t num = r.begin(); num != r.end(); ++num) {
                    size_t index_i = get_particle_index(num);
                    Vecd& particle_position = pos_n[index_i];
                    int search_depth = get_search_depth(index_i);
                    Vecu target_cell_index = CellIndexFromPosition(particle_position);
                    int i = (int)target_cell_index[0];
                    int j = (int)target_cell_index[1];

                    Neighborhood& neighborhood = particle_configuration[index_i];
                    for (int l = SMAX(i - search_depth, 0); l <= SMIN(i + search_depth, int(number_of_cells_[0]) - 1); ++l)
                        for (int m = SMAX(j - search_depth, 0); m <= SMIN(j + search_depth, int(number_of_cells_[1]) - 1); ++m)
                        {
                            ListDataVector& target_particles = cell_linked_lists_[l][m].cell_list_data_;
                            for (const ListData& list_data : target_particles)
                            {
                                //displacement pointing from neighboring particle to origin particle
                                Vecd displacement = particle_position - list_data.second;
                                get_neighbor_relation(neighborhood, displacement, index_i, list_data.first);
                            }
                        }
                }
            }, ap);
    }
    //=================================================================================================//
}