WReaderMatrixSymVTK.cpp

//---------------------------------------------------------------------------
//
// Project: OpenWalnut ( http://www.openwalnut.org )
//
// Copyright 2009 OpenWalnut Community, BSV@Uni-Leipzig and CNCF@MPI-CBS
// For more information see http://www.openwalnut.org/copying
//
// This file is part of OpenWalnut.
//
// OpenWalnut is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// OpenWalnut 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with OpenWalnut. If not, see <http://www.gnu.org/licenses/>.
//
//---------------------------------------------------------------------------
 
#include <fstream>
#include <memory>
#include <stdexcept>
#include <string>
#include <vector>
 
 
#include "../../common/WAssert.h"
#include "../../common/WIOTools.h"
#include "../../common/WLogger.h"
#include "../../common/WStringUtils.h"
#include "../exceptions/WDHException.h"
#include "../exceptions/WDHIOFailure.h"
#include "WReader.h"
#include "WReaderMatrixSymVTK.h"
 
WReaderMatrixSymVTK::WReaderMatrixSymVTK( std::string fname )
    : WReader( fname )
{
}
 
void WReaderMatrixSymVTK::readTable( std::shared_ptr< std::vector< double > > table ) const
{
    WAssert( table->size() == 0, "Non-zero size indicates an error, since the vector will be filled IN HERE." );
 
    // code mainly taken from WLoaderFibers.cpp, and adjusted since I don't
    // know how to code this DRY. Any suggestions?
    std::ifstream ifs;
    ifs.open( m_fname.c_str(), std::ifstream::in | std::ifstream::binary );
    WAssert( ifs && !ifs.bad(), "" );
 
    std::vector< std::string > header;
    std::string line;
    try
    {
        for( int i = 0; i < 4; ++i )  // strip first four lines
        {
            std::getline( ifs, line );
            if( !ifs.good() )
            {
                throw WDHException( std::string( "Unexpected end of file: " + m_fname ) );
            }
            header.push_back( line );
        }
    }
    catch( const std::ios_base::failure &e )
    {
        throw WDHIOFailure( std::string( "Reading first 4 lines of '" + m_fname + "': " + e.what() ) );
    }
    if( header[0] != "# vtk DataFile Version 3.0" )
    {
        wlog::warn( "WReaderMatrixSymVTK" ) << "Wrong version string in file header found, expected: "
                                               "\"# vtk DataFile Version 3.0\" but got: " << header[0];
    }
    if( header[2] != "BINARY" )
    {
        wlog::error( "WReaderMatrixSymVTK" ) << "Wrong data format: BINARY expected but got: " << header[2];
        throw WDHIOFailure( "Error reading file '" + m_fname + " invalid binary format." );
    }
    if( header[3] != "FIELD WMatrixSym 1" )
    {
        wlog::error( "WReaderMatrixSymVTK" ) << "Wrong field desc in file header found: " << header[3] << " but expected: \"FIELD WMatrixSym 1\"";
        throw WDHIOFailure( "Error reading file '" + m_fname + " invalid VTK field name." );
    }
 
    try
    {
        std::getline( ifs, line ); // something like this: "DISTANCES 15879430 1 float" expected
    }
    catch( const std::ios_base::failure &e )
    {
        throw WDHIOFailure( std::string( "Error reading ELEMENTS field '" + m_fname + "': " + e.what() ) );
    }
    namespace su = string_utils;
    size_t numDistances = 0;
    std::vector< std::string > tokens = su::tokenize( line );
    if( tokens.size() != 4 || su::toLower( tokens.at( 3 ) ) != "float" )
    {
        throw WDHException( std::string( "Invalid ELEMENTS declaration: " + line ) );
    }
    try
    {
        numDistances = string_utils::fromString< size_t >( tokens.at( 1 ) );
    }
    catch( const std::exception &e )
    {
        throw WDHException( std::string( "Invalid number of elements: " + tokens.at( 1 ) ) );
    }
 
    float *data = new float[ numDistances ];
    try
    {
        ifs.read( reinterpret_cast< char* >( data ), sizeof( float ) * numDistances );
    }
    catch( const std::ios_base::failure &e )
    {
        throw WDHIOFailure( std::string( "Error reading elements in VTK ELEMENTS field '" + m_fname + "': " + e.what() ) );
    }
 
    // all 4 bytes of each float are in wrong order we need to reorder them
    switchByteOrderOfArray( data, numDistances );
 
    for( size_t i = 0; i < numDistances; ++i )
    {
        table->push_back( static_cast< double >( data[ i ] ) );
    }
 
    delete[] data;
}