msh_gmshreader.cc

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/*!
 *
 * Copyright (C) 2015 Technical University of Liberec.  All rights reserved.
 * 
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License version 3 as published by the
 * Free Software Foundation. (http://www.gnu.org/licenses/gpl-3.0.en.html)
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 *
 * 
 * @file    msh_gmshreader.cc
 * @ingroup mesh
 * @brief   
 * @author  dalibor
 */

#include <istream>
#include <string>
#include <limits>

#include "msh_gmshreader.h"

#include "system/system.hh"
#include "system/sys_profiler.hh"
#include "system/tokenizer.hh"
#include "boost/lexical_cast.hpp"

#include "mesh/mesh.h"
#include "mesh/nodes.hh"


using namespace std;


GmshMeshReader::GmshMeshReader(const FilePath &file_name)
: tok_(file_name)
{
    current_cache_ = new ElementDataCacheBase();
    tok_.set_comment_pattern( "#");
    make_header_table();
}



GmshMeshReader::GmshMeshReader(std::istream &in)
: tok_(in)
{
    current_cache_ = new ElementDataCacheBase();
    tok_.set_comment_pattern( "#");
    make_header_table();
}



GmshMeshReader::~GmshMeshReader()   // Tokenizer close the file automatically
{}



void GmshMeshReader::read_mesh(Mesh* mesh) {
    START_TIMER("GMSHReader - read mesh");
    
    OLD_ASSERT( mesh , "Argument mesh is NULL.\n");
    tok_.set_position( Tokenizer::Position() );
    read_nodes(mesh);
    read_elements(mesh);
}



void GmshMeshReader::read_nodes(Mesh* mesh) {
    using namespace boost;
    MessageOut() << "- Reading nodes...";

    if (! tok_.skip_to("$Nodes")) THROW(ExcMissingSection() << EI_Section("$Nodes") << EI_GMSHFile(tok_.f_name()) );
    try {
        tok_.next_line(false);
        unsigned int n_nodes = lexical_cast<unsigned int> (*tok_);;
        INPUT_CHECK( n_nodes > 0, "Zero number of nodes, %s.\n", tok_.position_msg().c_str() );
        ++tok_; // end of line

        mesh->node_vector.reserve(n_nodes);
        for (unsigned int i = 0; i < n_nodes; ++i) {
            tok_.next_line();

            unsigned int id = lexical_cast<unsigned int> (*tok_); ++tok_;
            NodeFullIter node = mesh->node_vector.add_item(id);

            node->point()(0)=lexical_cast<double> (*tok_); ++tok_;
            node->point()(1)=lexical_cast<double> (*tok_); ++tok_;
            node->point()(2)=lexical_cast<double> (*tok_); ++tok_;
            ++tok_; // skip mesh size parameter
        }

    } catch (bad_lexical_cast &) {
        THROW(ExcWrongFormat() << EI_Type("number") << EI_TokenizerMsg(tok_.position_msg()) << EI_GMSHFile(tok_.f_name()) );
    }
    MessageOut().fmt("... {} nodes read. \n", mesh->node_vector.size());
}



void GmshMeshReader::read_elements(Mesh * mesh) {
    using namespace boost;
    MessageOut() << "- Reading elements...";

    if (! tok_.skip_to("$Elements")) THROW(ExcMissingSection() << EI_Section("$Elements") << EI_GMSHFile(tok_.f_name()) );
    try {
        tok_.next_line(false);
        unsigned int n_elements = lexical_cast<unsigned int> (*tok_);
        INPUT_CHECK( n_elements > 0, "Zero number of elements, %s.\n", tok_.position_msg().c_str());
        ++tok_; // end of line

        mesh->element.reserve(n_elements);

        for (unsigned int i = 0; i < n_elements; ++i) {
            tok_.next_line();

            unsigned int id = lexical_cast<unsigned int>(*tok_); ++tok_;


            //get element type: supported:
            //  1 Line (2 nodes)
            //  2 Triangle (3 nodes)
            //  4 Tetrahedron (4 nodes)
            // 15 Point (1 node)
            unsigned int type = lexical_cast<unsigned int>(*tok_); ++tok_;
            unsigned int dim;
            switch (type) {
                case 1:
                    dim = 1;
                    break;
                case 2:
                    dim = 2;
                    break;
                case 4:
                    dim = 3;
                    break;
                case 15:
                    dim = 0;
                    break;
                default:
                    dim = 0;
                    THROW(ExcUnsupportedType() << EI_ElementId(id) << EI_ElementType(type) << EI_GMSHFile(tok_.f_name()) );
                    break;
            }

            //get number of tags (at least 2)
            unsigned int n_tags = lexical_cast<unsigned int>(*tok_);
            INPUT_CHECK(n_tags >= 2, "At least two element tags have to be defined for element with id=%d, %s.\n",
                    id, tok_.position_msg().c_str());
            ++tok_;

            //get tags 1 and 2
            unsigned int region_id = lexical_cast<unsigned int>(*tok_); ++tok_;
            lexical_cast<unsigned int>(*tok_); ++tok_; // GMSH region number, we do not store this
            //get remaining tags
            unsigned int partition_id=0;
            if (n_tags > 2)  { partition_id = lexical_cast<unsigned int>(*tok_); ++tok_; } // save partition number from the new GMSH format
            for (unsigned int ti = 3; ti < n_tags; ti++) ++tok_;         //skip remaining tags

            // allocate element arrays TODO: should be in mesh class
            Element *ele=nullptr;
            RegionIdx region_idx = mesh->region_db_.get_region( region_id, dim );
            if ( !region_idx.is_valid() ) {
                region_idx = mesh->region_db_.add_region( region_id, mesh->region_db_.create_label_from_id(region_id),
                                                          dim, "$Element" );
            }
            mesh->region_db_.mark_used_region(region_idx.idx());

            if (region_idx.is_boundary()) {
                ele = mesh->bc_elements.add_item(id);
            } else {
                if(dim == 0 )
                    WarningOut().fmt("Bulk elements of zero size(dim=0) are not supported. Mesh file: {}, Element ID: {}.\n", tok_.f_name() ,id);
                else
                    ele = mesh->element.add_item(id);
            }
            ele->init(dim, mesh, region_idx);
            ele->pid=partition_id;

            unsigned int ni;
            FOR_ELEMENT_NODES(ele, ni) {
                unsigned int node_id = lexical_cast<unsigned int>(*tok_);
                NodeIter node = mesh->node_vector.find_id( node_id );
                INPUT_CHECK( node!=mesh->node_vector.end() ,
                        "Unknown node id %d in specification of element with id=%d, %s.\n",
                        node_id, id, tok_.position_msg().c_str());
                ele->node[ni] = node;
                ++tok_;
            }
        }

    } catch (bad_lexical_cast &) {
        THROW(ExcWrongFormat() << EI_Type("number") << EI_TokenizerMsg(tok_.position_msg()) << EI_GMSHFile(tok_.f_name()) );
    }

    mesh->n_all_input_elements_=mesh->element.size() + mesh->bc_elements.size();
    MessageOut().fmt("... {} bulk elements, {} boundary elements. \n", mesh->element.size(), mesh->bc_elements.size());
}



void GmshMeshReader::read_physical_names(Mesh * mesh) {
    OLD_ASSERT( mesh , "Argument mesh is NULL.\n");
    using namespace boost;

    if (! tok_.skip_to("$PhysicalNames", "$Nodes") ) return;
    try {
        tok_.next_line(false);
        unsigned int n_physicals = lexical_cast<unsigned int> (*tok_);
        ++tok_; // end of line

        for (unsigned int i = 0; i < n_physicals; ++i) {
            tok_.next_line();
            // format of one line:
            // dim    physical-id    physical-name

            unsigned int dim = lexical_cast<unsigned int>(*tok_); ++tok_;
            unsigned int id = lexical_cast<unsigned int>(*tok_); ++tok_;
            string name = *tok_; ++tok_;

            mesh->region_db_.add_region(id, name, dim, "$PhysicalNames");
        }

    } catch (bad_lexical_cast &) {
        THROW(ExcWrongFormat() << EI_Type("number") << EI_TokenizerMsg(tok_.position_msg()) << EI_GMSHFile(tok_.f_name()) );
    }
}


// Is assumed to be called just after tok.skip_to("..")
// reads the header from the tokenizer @p tok and return it as the second parameter
void GmshMeshReader::read_data_header(GMSH_DataHeader &head) {
    using namespace boost;
    try {
        // string tags
        tok_.next_line(false);
        unsigned int n_str = lexical_cast<unsigned int>(*tok_); ++tok_;
        head.field_name="";
        head.interpolation_scheme = "";
        if (n_str > 0) {
            tok_.next_line(); n_str--;
            head.field_name= *tok_; ++tok_; //  unquoted by tokenizer if needed
        }
        if (n_str > 0) {
            tok_.next_line(); n_str--;
            head.interpolation_scheme = *tok_; ++tok_;
        }
        for(;n_str>0;n_str--) tok_.next_line(false); // skip possible remaining tags

        //real tags
        tok_.next_line();
        unsigned int n_real = lexical_cast<unsigned int>(*tok_); ++tok_;
        head.time=0.0;
        if (n_real>0) {
            tok_.next_line(); n_real--;
            head.time=lexical_cast<double>(*tok_); ++tok_;
        }
        for(;n_real>0;n_real--) tok_.next_line(false);

        // int tags
        tok_.next_line();
        unsigned int n_int = lexical_cast<unsigned int>(*tok_); ++tok_;
        head.time_index=0;
        head.n_components=1;
        head.n_entities=0;
        head.partition_index=0;
        if (n_int>0) {
            tok_.next_line(); n_int--;
            head.time_index=lexical_cast<unsigned int>(*tok_); ++tok_;
        }
        if (n_int>0) {
            tok_.next_line(); n_int--;
            head.n_components=lexical_cast<unsigned int>(*tok_); ++tok_;
        }
        if (n_int>0) {
            tok_.next_line(); n_int--;
            head.n_entities=lexical_cast<unsigned int>(*tok_); ++tok_;
        }
        for(;n_int>0;n_int--) tok_.next_line(false);
        head.position = tok_.get_position();
    } catch (bad_lexical_cast &) {
        THROW(ExcWrongFormat() << EI_Type("$ElementData header") << EI_TokenizerMsg(tok_.position_msg()) << EI_GMSHFile(tok_.f_name()) );
    }
}



template<typename T>
typename ElementDataCache<T>::ComponentDataPtr GmshMeshReader::get_element_data( GMSH_DataHeader &search_header,
        std::vector<int> const & el_ids, unsigned int component_idx)
{
    using namespace boost;

    GMSH_DataHeader actual_header = find_header(search_header.time, search_header.field_name);
    if ( !current_cache_->is_actual(actual_header.time, search_header.field_name) ) {

        unsigned int id, idx, i_row;
        unsigned int n_read = 0;
        unsigned int size_of_cache; // count of vectors stored in cache
        vector<int>::const_iterator id_iter = el_ids.begin();

        // check that the header is valid, try to correct
        if (actual_header.n_entities != search_header.n_entities) {
            WarningOut().fmt("In file '{}', '$ElementData' section for field '{}', time: {}.\nWrong number of entities: {}, using {} instead.\n",
                    tok_.f_name(), search_header.field_name, actual_header.time, actual_header.n_entities, search_header.n_entities);
            // actual_header.n_entities=search_header.n_entities;
        }

        if (search_header.n_components == 1) {
            // read for MultiField to 'n_comp' vectors
            // or for Field if ElementData contains only one value
            size_of_cache = actual_header.n_components;
        }
        else {
            // read for Field if more values is stored to one vector
            size_of_cache = 1;
            if (actual_header.n_components != search_header.n_components) {
                WarningOut().fmt("In file '{}', '$ElementData' section for field '{}', time: {}.\nWrong number of components: {}, using {} instead.\n",
                        tok_.f_name(), search_header.field_name, actual_header.time, actual_header.n_components, search_header.n_components);
                actual_header.n_components=search_header.n_components;
            }
        }

        // create vector of shared_ptr for cache
        typename ElementDataCache<T>::CacheData data_cache(size_of_cache);
        for (unsigned int i=0; i<size_of_cache; ++i) {
            typename ElementDataCache<T>::ComponentDataPtr row_vec = std::make_shared<std::vector<T>>();
            row_vec->resize(search_header.n_components*search_header.n_entities);
            data_cache[i] = row_vec;
        }

        // read @p data buffer as we have correct header with already passed time
        // we assume that @p data buffer is big enough
        tok_.set_position(actual_header.position);

        // read data
        for (i_row = 0; i_row < actual_header.n_entities; ++i_row)
            try {
                tok_.next_line();
                id = lexical_cast<unsigned int>(*tok_); ++tok_;
                //skip_element = false;
                while (id_iter != el_ids.end() && *id_iter < (int)id) {
                    ++id_iter; // skip initialization of some rows in data if ID is missing
                }
                if (id_iter == el_ids.end()) {
                    WarningOut().fmt("In file '{}', '$ElementData' section for field '{}', time: {}.\nData ID {} not found or is not in order. Skipping rest of data.\n",
                            tok_.f_name(), search_header.field_name, actual_header.time, id);
                    break;
                }
                // save data from the line if ID was found
                if (*id_iter == (int)id) {
                    for (unsigned int i_vec=0; i_vec<size_of_cache; ++i_vec) {
                        idx = (id_iter - el_ids.begin()) * search_header.n_components;
                        std::vector<T> &vec = *( data_cache[i_vec].get() );
                        for (unsigned int i_col=0; i_col < search_header.n_components; ++i_col, ++idx) {
                            vec[idx] = lexical_cast<T>(*tok_);
                            ++tok_;
                        }
                    }
                    n_read++;
                }
                // skip the line if ID on the line  < actual ID in the map el_ids
            } catch (bad_lexical_cast &) {
                THROW(ExcWrongFormat() << EI_Type("$ElementData line") << EI_TokenizerMsg(tok_.position_msg())
                        << EI_GMSHFile(tok_.f_name()) );
            }
        // possibly skip remaining lines after break
        while (i_row < actual_header.n_entities) tok_.next_line(false), ++i_row;

        LogOut().fmt("time: {}; {} entities of field {} read.\n",
                actual_header.time, n_read, actual_header.field_name);

        search_header.actual = true; // use input header to indicate modification of @p data buffer

        // set new cache
        delete current_cache_;
        current_cache_ = new ElementDataCache<T>(actual_header.time, actual_header.field_name, data_cache);
    }

    if (component_idx == std::numeric_limits<unsigned int>::max()) component_idx = 0;
    return static_cast< ElementDataCache<T> *>(current_cache_)->get_component_data(component_idx);
}



void GmshMeshReader::make_header_table()
{
    header_table_.clear();
    GMSH_DataHeader header;
    while ( !tok_.eof() ) {
        if ( tok_.skip_to("$ElementData") ) {
            read_data_header(header);
            HeaderTable::iterator it = header_table_.find(header.field_name);

            if (it == header_table_.end()) {  // field doesn't exists, insert new vector to map
                std::vector<GMSH_DataHeader> vec;
                vec.push_back(header);
                header_table_[header.field_name]=vec;
            } else if ( header.time <= it->second.back().time ) { // time is in wrong order. can't be add
                WarningOut().fmt("Wrong time order: field '{}', time '{}', file '{}'. Skipping this '$ElementData' section.\n",
                    header.field_name, header.time, tok_.f_name() );
            } else {  // add new time step
                it->second.push_back(header);
            }
        }
    }

    tok_.set_position( Tokenizer::Position() );
}



GMSH_DataHeader &  GmshMeshReader::find_header(double time, std::string field_name)
{
    HeaderTable::iterator table_it = header_table_.find(field_name);

    if (table_it == header_table_.end()) {
        // no data found
        THROW( ExcFieldNameNotFound() << EI_FieldName(field_name) << EI_GMSHFile(tok_.f_name()));
    }

    auto comp = [](double t, const GMSH_DataHeader &a) {
        return t * (1.0 + 2.0*numeric_limits<double>::epsilon()) < a.time;
    };

    std::vector<GMSH_DataHeader>::iterator headers_it = std::upper_bound(table_it->second.begin(),
            table_it->second.end(),
            time,
            comp);

    if (headers_it == table_it->second.begin()) {
        THROW( ExcFieldNameNotFound() << EI_FieldName(field_name)
                                      << EI_GMSHFile(tok_.f_name()) << EI_Time(time));
    }

    --headers_it;
    return *headers_it;
}


// explicit instantiation of template methods
#define READER_GET_ELEMENT_DATA(TYPE) \
template typename ElementDataCache<TYPE>::ComponentDataPtr GmshMeshReader::get_element_data<TYPE>(GMSH_DataHeader &search_header, \
    std::vector<int> const & el_ids, unsigned int component_idx)

READER_GET_ELEMENT_DATA(int);
READER_GET_ELEMENT_DATA(unsigned int);
READER_GET_ELEMENT_DATA(double);