grid_memory.cpp

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//                                                       //
//                         SAGA                          //
//                                                       //
//      System for Automated Geoscientific Analyses      //
//                                                       //
//           Application Programming Interface           //
//                                                       //
//                  Library: SAGA_API                    //
//                                                       //
//-------------------------------------------------------//
//                                                       //
//                   grid_memory.cpp                     //
//                                                       //
//          Copyright (C) 2005 by Olaf Conrad            //
//                                                       //
//-------------------------------------------------------//
//                                                       //
// This file is part of 'SAGA - System for Automated     //
// Geoscientific Analyses'.                              //
//                                                       //
// This library 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 2.1 of the        //
// License, or (at your option) any later version.       //
//                                                       //
// This library 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 this program; if    //
// not, see <http://www.gnu.org/licenses/>.              //
//                                                       //
//-------------------------------------------------------//
//                                                       //
//    contact:    Olaf Conrad                            //
//                Institute of Geography                 //
//                University of Goettingen               //
//                Goldschmidtstr. 5                      //
//                37077 Goettingen                       //
//                Germany                                //
//                                                       //
//    e-mail:     oconrad@saga-gis.org                   //
//                                                       //
 
//---------------------------------------------------------
#include <memory.h>
 
#include "grid.h"
#include "parameters.h"
 

//                                                       //
//                   Caching Options                     //
//                                                       //
 
//---------------------------------------------------------
static CSG_String     gSG_Grid_Cache_Directory;
 
//---------------------------------------------------------
const SG_Char *          SG_Grid_Cache_Get_Directory(void)
{
        return( gSG_Grid_Cache_Directory );
}
 
//---------------------------------------------------------
void                            SG_Grid_Cache_Set_Directory(const SG_Char *Directory)
{
        if( SG_Dir_Exists(Directory) )
        {
                gSG_Grid_Cache_Directory = Directory;
        }
}
 

//                                                       //
 
//---------------------------------------------------------
static int gSG_Grid_Cache_Mode = 0;
 
//---------------------------------------------------------
void                            SG_Grid_Cache_Set_Mode(int Mode)
{
        gSG_Grid_Cache_Mode = Mode;
}
 
//---------------------------------------------------------
int                                     SG_Grid_Cache_Get_Mode(void)
{
        return( gSG_Grid_Cache_Mode );
}
 

//                                                       //
 
//---------------------------------------------------------
static sLong gSG_Grid_Cache_Threshold = 0;
 
//---------------------------------------------------------
void                            SG_Grid_Cache_Set_Threshold(int nBytes)
{
        if( nBytes >= 0 )
        {
                gSG_Grid_Cache_Threshold = nBytes;
        }
}
 
//---------------------------------------------------------
void                            SG_Grid_Cache_Set_Threshold_MB(double nMegabytes)
{
        SG_Grid_Cache_Set_Threshold((int)(nMegabytes * N_MEGABYTE_BYTES));
}
 
//---------------------------------------------------------
sLong                              SG_Grid_Cache_Get_Threshold(void)
{
        return( gSG_Grid_Cache_Threshold );
}
 
//---------------------------------------------------------
double                          SG_Grid_Cache_Get_Threshold_MB(void)
{
        return( (double)gSG_Grid_Cache_Threshold / (double)N_MEGABYTE_BYTES );
}
 

//                                                       //
//                       Memory                          //
//                                                       //
 
//---------------------------------------------------------
bool CSG_Grid::_Memory_Create(bool bCached)
{
        if( !m_System.is_Valid() || m_Type == SG_DATATYPE_Undefined )
        {
                return( false );
        }
 
        _Memory_Destroy();
 
        if(     bCached || _Cache_Check() )
        {
                return( _Cache_Create() );
        }
 
        return( _Array_Create() );
}
 
//---------------------------------------------------------
void CSG_Grid::_Memory_Destroy(void)
{
        SG_FREE_SAFE(m_Index);
 
        if( is_Cached() )
        {
                _Cache_Destroy(false);
        }
 
        _Array_Destroy();
}
 

//                                                       //
//                        Array                          //
//                                                       //
 
//---------------------------------------------------------
bool CSG_Grid::_Array_Create(void)
{
        if( m_System.is_Valid() && m_Type != SG_DATATYPE_Undefined )
        {
                _Array_Destroy();
 
                if( (m_Values = (void **)SG_Malloc(Get_NY() * sizeof(void *))) != NULL )
                {               
                        if( (m_Values[0] = (void  *)SG_Calloc(Get_NY(), Get_nLineBytes())) != NULL )
                        {
                                char *pLine = (char *)m_Values[0];
 
                                for(int y=0; y<Get_NY(); y++, pLine+=Get_nLineBytes())
                                {
                                        m_Values[y]      = pLine;
                                }
 
                                return( true );
                        }
 
                        SG_Free(m_Values);
 
                        m_Values = NULL;
                }
 
                SG_UI_Msg_Add_Error(CSG_String::Format("%s: %s [%.2fmb]", _TL("grid"), _TL("memory allocation failed"), (double)Get_NY() * Get_nLineBytes() / N_MEGABYTE_BYTES));
        }
 
        return( false );
}
 
//---------------------------------------------------------
void CSG_Grid::_Array_Destroy(void)
{
        if( m_Values )
        {
                SG_Free(m_Values[0]);
                SG_Free(m_Values);
 
                m_Values = NULL;
        }
}
 

//                                                       //
//                        Cache                          //
//                                                       //
 
//---------------------------------------------------------
#define CACHE_FILE_POS(x, y) (m_Cache_Offset + (m_Cache_bFlip ? Get_NY() - 1 - y : y) * m_nBytes_Line + x * m_nBytes_Value)
 
//---------------------------------------------------------
#if defined(_SAGA_LINUX)
#define CACHE_FILE_SEEK fseek
#else
#define CACHE_FILE_SEEK _fseeki64
#endif
 
//---------------------------------------------------------
bool CSG_Grid::Set_Cache(bool bOn)
{
        if( bOn )
        {
                return( is_Cached()
                        || _Cache_Create(m_Cache_File                                  , m_Type, m_Cache_Offset, m_Cache_bSwap, m_Cache_bFlip)
                        || _Cache_Create(SG_File_Make_Path("", Get_File_Name(),  "dat"), m_Type, m_Cache_Offset, m_Cache_bSwap, m_Cache_bFlip)
                        || _Cache_Create(SG_File_Make_Path("", Get_File_Name(), "sdat"), m_Type, m_Cache_Offset, m_Cache_bSwap, m_Cache_bFlip)
                        || _Cache_Create()
                );
        }
 
        return( !is_Cached() || _Cache_Destroy(true) );
}
 

//                                                       //
 
//---------------------------------------------------------
bool CSG_Grid::_Cache_Check(void)
{
        sLong nBytes = m_System.Get_NCells() * Get_nValueBytes();
 
        if(     SG_Grid_Cache_Get_Mode() > 0 && nBytes > SG_Grid_Cache_Get_Threshold() )
        {
                if( SG_Grid_Cache_Get_Mode() == 2 )       // confirm
                {
                        CSG_String s;
 
                        s.Printf("%s\n%s\n%s: %.2fMB",
                                _TL("Shall I activate file caching for new grid."),
                                m_System.Get_Name(),
                                _TL("Total memory size"),
                                (double)nBytes / (double)N_MEGABYTE_BYTES
                        );
 
                        return( SG_UI_Dlg_Continue(s, _TL("Activate Grid File Cache?")) );
                }
 
                return( true );
        }
 
        return( false );
}
 

//                                                       //
 
//---------------------------------------------------------
bool CSG_Grid::_Cache_Create(const CSG_String &File, TSG_Data_Type Data_Type, sLong Offset, bool bSwap, bool bFlip) // open existing file for caching
{
        if( !m_System.is_Valid() || m_Type != Data_Type || !SG_File_Exists(File) )
        {
                return( false );
        }
 
        if( (m_Cache_Stream = fopen(File, "r+b")) == NULL       // read and write
        &&  (m_Cache_Stream = fopen(File, "rb" )) == NULL )     // read only
        {
                return( false );
        }
 
        m_Cache_File   = File;
        m_Cache_bTemp  = false;
        m_Cache_Offset = Offset;
        m_Cache_bSwap  = m_Type == SG_DATATYPE_Bit ? false : bSwap;
        m_Cache_bFlip  = bFlip;
 
        _Array_Destroy();
 
        return( true );
}
 
//---------------------------------------------------------
bool CSG_Grid::_Cache_Create(void)      // create temporary cache file
{
        if( !m_System.is_Valid() || (m_Type == SG_DATATYPE_Undefined && is_Cached()) )
        {
                return( false );
        }
 
        CSG_String File = SG_File_Get_Name_Temp("sg_grd", SG_Grid_Cache_Get_Directory());
 
        if( (m_Cache_Stream = fopen(File, "w+b")) == NULL )     // read and write, create empty
        {
                return( false );
        }
 
        m_Cache_File   = File;
        m_Cache_bTemp  = true;
        m_Cache_Offset = 0;
        m_Cache_bSwap  = false;
        m_Cache_bFlip  = false;
 
        CSG_Array Values(1, m_Values ? 0 : Get_nLineBytes()); // dummy
 
        for(int y=0; y<Get_NY() && SG_UI_Process_Set_Progress(y, Get_NY()); y++)
        {
                fwrite(m_Values ? m_Values[y] : Values.Get_Array(), 1, Get_nLineBytes(), m_Cache_Stream);
        }
 
        SG_UI_Process_Set_Ready();
 
        _Array_Destroy();
 
        return( true );
}
 
//---------------------------------------------------------
bool CSG_Grid::_Cache_Destroy(bool bMemory_Restore)
{
        if( is_Cached() )
        {
                if( bMemory_Restore && _Array_Create() && !CACHE_FILE_SEEK(m_Cache_Stream, m_Cache_Offset, SEEK_SET) )
                {
                        for(int y=0; y<Get_NY() && SG_UI_Process_Set_Progress(y, Get_NY()); y++)
                        {
                                size_t nBytes = fread(m_Values[m_Cache_bFlip ? Get_NY() - 1 - y : y], 1, Get_nLineBytes(), m_Cache_Stream);
 
                                if( nBytes && m_Cache_bSwap )
                                {
                                        char *pValue = (char *)m_Values[y];
 
                                        for(int x=0; x<Get_NX(); x++, pValue+=Get_nValueBytes())
                                        {
                                                _Swap_Bytes(pValue, Get_nValueBytes());
                                        }
                                }
                        }
 
                        SG_UI_Process_Set_Ready();
                }
 
                //-------------------------------------------------
                fclose(m_Cache_Stream);
 
                m_Cache_Stream = NULL;
 
                if( m_Cache_bTemp )
                {
                        SG_File_Delete(m_Cache_File);
                }
 
                return( true );
        }
 
        return( false );
}
 

//                                                       //
 
//---------------------------------------------------------
void CSG_Grid::_Cache_Set_Value(int x, int y, double Value)
{
        char Buffer[8];
 
        switch( m_Type )
        {
        case SG_DATATYPE_Float : (*(float  *)Buffer) = (float          )(Value); break;
        case SG_DATATYPE_Double: (*(double *)Buffer) = (double         )(Value); break;
        case SG_DATATYPE_Byte  : (*(BYTE   *)Buffer) = SG_ROUND_TO_BYTE (Value); break;
        case SG_DATATYPE_Char  : (*(char   *)Buffer) = SG_ROUND_TO_CHAR (Value); break;
        case SG_DATATYPE_Word  : (*(WORD   *)Buffer) = SG_ROUND_TO_WORD (Value); break;
        case SG_DATATYPE_Short : (*(short  *)Buffer) = SG_ROUND_TO_SHORT(Value); break;
        case SG_DATATYPE_DWord : (*(DWORD  *)Buffer) = SG_ROUND_TO_DWORD(Value); break;
        case SG_DATATYPE_Int   : (*(int    *)Buffer) = SG_ROUND_TO_INT  (Value); break;
        case SG_DATATYPE_Long  : (*(sLong  *)Buffer) = SG_ROUND_TO_SLONG(Value); break;
 
        default: return;
        }
 
        if( m_Cache_bSwap )
        {
                _Swap_Bytes(Buffer, Get_nValueBytes());
        }
 
        if( !CACHE_FILE_SEEK(m_Cache_Stream, CACHE_FILE_POS(x, y), SEEK_SET) )
        {
                fwrite(Buffer, 1, Get_nValueBytes(), m_Cache_Stream);
        }
}
 
//---------------------------------------------------------
double CSG_Grid::_Cache_Get_Value(int x, int y) const
{
        if( !CACHE_FILE_SEEK(m_Cache_Stream, CACHE_FILE_POS(x, y), SEEK_SET) )
        {
                char Buffer[8];
 
                if( fread(Buffer, 1, Get_nValueBytes(), m_Cache_Stream) == (size_t)Get_nValueBytes() )
                {
                        switch( m_Type )
                        {
                        case SG_DATATYPE_Byte  : return( (double)(*(BYTE   *)Buffer) );
                        case SG_DATATYPE_Char  : return( (double)(*(char   *)Buffer) );
                        case SG_DATATYPE_Word  : return( (double)(*(WORD   *)Buffer) );
                        case SG_DATATYPE_Short : return( (double)(*(short  *)Buffer) );
                        case SG_DATATYPE_DWord : return( (double)(*(DWORD  *)Buffer) );
                        case SG_DATATYPE_Int   : return( (double)(*(int    *)Buffer) );
                        case SG_DATATYPE_Long  : return( (double)(*(sLong  *)Buffer) );
                        case SG_DATATYPE_Float : return( (double)(*(float  *)Buffer) );
                        case SG_DATATYPE_Double: return( (double)(*(double *)Buffer) );
 
                        default: break;
                        }
 
                        if( m_Cache_bSwap )
                        {
                                _Swap_Bytes(Buffer, Get_nValueBytes());
                        }
                }
        }
 
        return( 0. );
}
 

//                                                       //
//                                                       //
//                                                       //
 
//---------------------------------------------------------