ntffilereader.cpp

支持各种栅格图像和矢量图像读取的库

      
        poGeometry = new OGRPoint( dfX, dfY, dfZ );
    }
    
    else if( nGType == 2 )
    {
        OGRLineString      *poLine = new OGRLineString;
        double             dfX, dfY, dfZ, dfXLast=0.0, dfYLast=0.0;
        int                iCoord, nOutCount = 0;

        poGeometry = poLine;
        poLine->setNumPoints( nNumCoord );
        for( iCoord = 0; iCoord < nNumCoord; iCoord++ )
        {
            int            iStart = 14 + iCoord * (GetXYLen()*2+nZWidth+2);

            dfX = atoi(poRecord->GetField(iStart+0,
                                          iStart+GetXYLen()-1)) 
                * GetXYMult() + GetXOrigin();
            dfY = atoi(poRecord->GetField(iStart+GetXYLen(),
                                          iStart+GetXYLen()*2-1)) 
                * GetXYMult() + GetYOrigin();

            dfZ = atoi(poRecord->GetField(iStart+1+2*GetXYLen(),
                                          iStart+1+2*GetXYLen()+nZWidth-1))
                * dfZMult;

            if( iCoord == 0 )
            {
                dfXLast = dfX;
                dfYLast = dfY;
                poLine->setPoint( nOutCount++, dfX, dfY, dfZ );
            }
            else if( dfXLast != dfX || dfYLast != dfY )
            {
                dfXLast = dfX;
                dfYLast = dfY;
                poLine->setPoint( nOutCount++, dfX, dfY, dfZ );
            }
        }
        poLine->setNumPoints( nOutCount );

        CacheAddByGeomId( atoi(poRecord->GetField(3,8)), poLine );
    }

    if( poGeometry != NULL )
        poGeometry->assignSpatialReference( poDS->GetSpatialRef() );
    
    return poGeometry;
}

/************************************************************************/
/*                           ProcessAttDesc()                           */
/************************************************************************/

int NTFFileReader::ProcessAttDesc( NTFRecord * poRecord, NTFAttDesc* psAD )

{
    int      iChar;
    const char *pszData;

    if( poRecord->GetType() != NRT_ADR )
        return FALSE;

    psAD->poCodeList = NULL;
    strcpy( psAD->val_type, poRecord->GetField( 3, 4 ));
    strcpy( psAD->fwidth, poRecord->GetField( 5, 7 ));
    strcpy( psAD->finter, poRecord->GetField( 8, 12 ));
    
    pszData = poRecord->GetData();
    for( iChar = 12; 
         pszData[iChar] != '\0' && pszData[iChar] != '\\';
         iChar++ ) {}

    strcpy( psAD->att_name, poRecord->GetField( 13, iChar ));

    return TRUE;
}

/************************************************************************/
/*                         ProcessAttRecGroup()                         */
/*                                                                      */
/*      Extract attribute values from all attribute records in a        */
/*      record set.                                                     */
/************************************************************************/

int NTFFileReader::ProcessAttRecGroup( NTFRecord **papoRecords,
                                       char ***ppapszTypes,
                                       char ***ppapszValues )

{
    *ppapszTypes = NULL;
    *ppapszValues = NULL;
    
    for( int iRec = 0; papoRecords[iRec] != NULL; iRec++ )
    {
        char    **papszTypes1 = NULL, **papszValues1 = NULL;
        
        if( papoRecords[iRec]->GetType() != NRT_ATTREC )
            continue;

        if( !ProcessAttRec( papoRecords[iRec], NULL,
                            &papszTypes1, &papszValues1 ) )
            return FALSE;

        if( *ppapszTypes == NULL )
        {
            *ppapszTypes = papszTypes1;
            *ppapszValues = papszValues1;
        }
        else
        {
            for( int i=0; papszTypes1[i] != NULL; i++ )
            {
                *ppapszTypes = CSLAddString( *ppapszTypes, papszTypes1[i] );
                *ppapszValues = CSLAddString( *ppapszValues, papszValues1[i] );
            }
            CSLDestroy( papszTypes1 );
            CSLDestroy( papszValues1 );
        }
    }

    return TRUE;
}

/************************************************************************/
/*                           ProcessAttRec()                            */
/************************************************************************/

int NTFFileReader::ProcessAttRec( NTFRecord * poRecord, 
                                  int *pnAttId,
                                  char *** ppapszTypes, 
                                  char *** ppapszValues )

{
    int            iOffset;
    const char     *pszData;

    if( poRecord->GetType() != NRT_ATTREC )
        return FALSE;

/* -------------------------------------------------------------------- */
/*      Extract the attribute id.                                       */
/* -------------------------------------------------------------------- */
    if( pnAttId != NULL )
        *pnAttId = atoi(poRecord->GetField(3,8));

/* ==================================================================== */
/*      Loop handling attribute till we get a '0' indicating the end    */
/*      of the record.                                                  */
/* ==================================================================== */
    *ppapszTypes = NULL;
    *ppapszValues = NULL;

    iOffset = 8;
    pszData = poRecord->GetData();

    while( pszData[iOffset] != '0' && pszData[iOffset] != '\0' )
    {
        NTFAttDesc *psAttDesc;
        int         nEnd;
        int         nFWidth;

/* -------------------------------------------------------------------- */
/*      Extract the two letter code name for the attribute, and use     */
/*      it to find the correct ATTDESC info.                            */
/* -------------------------------------------------------------------- */
        psAttDesc = GetAttDesc(pszData + iOffset );
        if( psAttDesc == NULL )
        {
            CPLDebug( "NTF", "Couldn't translate attrec type `%2.2s'.", 
                      pszData + iOffset );
            return FALSE;
        }

        *ppapszTypes =
            CSLAddString( *ppapszTypes, 
                          poRecord->GetField(iOffset+1,iOffset+2) );

/* -------------------------------------------------------------------- */
/*      Establish the width of the value.  Zero width fields are        */
/*      terminated by a backslash.                                      */
/* -------------------------------------------------------------------- */
        nFWidth = atoi(psAttDesc->fwidth);
        if( nFWidth == 0 )
        {
            const char * pszData = poRecord->GetData();

            for( nEnd = iOffset + 2; 
                 pszData[nEnd] != '\\' && pszData[nEnd] != '\0';
                 nEnd++ ) {}
        }
        else
        {
            nEnd = iOffset + 3 + nFWidth - 1;
        }

/* -------------------------------------------------------------------- */
/*      Extract the value.  If it is formatted as fixed point real      */
/*      we reprocess it to insert the decimal point.                    */
/* -------------------------------------------------------------------- */
        const char * pszRawValue = poRecord->GetField(iOffset+3,nEnd);
        *ppapszValues = CSLAddString( *ppapszValues, pszRawValue );

/* -------------------------------------------------------------------- */
/*      Establish new offset position.                                  */
/* -------------------------------------------------------------------- */
        if( nFWidth == 0 )
        {
            iOffset = nEnd;
            if( pszData[iOffset] == '\\' )
                iOffset++;
        }
        else
            iOffset += 2 + atoi(psAttDesc->fwidth);
    }

    return TRUE;
}

/************************************************************************/
/*                             GetAttDesc()                             */
/************************************************************************/

NTFAttDesc * NTFFileReader::GetAttDesc( const char * pszType )

{
    for( int i = 0; i < nAttCount; i++ )
    {
        if( EQUALN(pszType, pasAttDesc[i].val_type, 2) )
            return pasAttDesc + i;
    }

    return NULL;
}

/************************************************************************/
/*                          ProcessAttValue()                           */
/*                                                                      */
/*      Take an attribute type/value pair and transform into a          */
/*      meaningful attribute name, and value.  The source can be an     */
/*      ATTREC or the VAL_TYPE/VALUE pair of a POINTREC or LINEREC.     */
/*      The name is transformed from the two character short form to    */
/*      the long user name.  The value will be transformed from         */
/*      fixed point (with the decimal implicit) to fixed point with     */
/*      an explicit decimal point if it has a "R" format.               */
/************************************************************************/

int NTFFileReader::ProcessAttValue( const char *pszValType, 
                                    const char *pszRawValue,
                                    char **ppszAttName, 
                                    char **ppszAttValue,
                                    char **ppszCodeDesc )

{
/* -------------------------------------------------------------------- */
/*      Find the ATTDESC for this attribute, and assign return name value.*/
/* -------------------------------------------------------------------- */
    NTFAttDesc      *psAttDesc = GetAttDesc(pszValType);

    if( psAttDesc == NULL )
        return FALSE;

    if( ppszAttName != NULL )
        *ppszAttName = psAttDesc->att_name;

/* -------------------------------------------------------------------- */
/*      Extract the value.  If it is formatted as fixed point real      */
/*      we reprocess it to insert the decimal point.                    */
/* -------------------------------------------------------------------- */
    if( psAttDesc->finter[0] == 'R' )
    {
        static char      szRealString[30];
        const char *pszDecimalPortion;
        int       nWidth, nPrecision;

        for( pszDecimalPortion = psAttDesc->finter; 
             *pszDecimalPortion != ',' && *pszDecimalPortion != '\0';
             pszDecimalPortion++ ) {}

        nWidth = strlen(pszRawValue);
        nPrecision = atoi(pszDecimalPortion+1);

        strncpy( szRealString, pszRawValue, nWidth - nPrecision );
        szRealString[nWidth-nPrecision] = '.';
        strcpy( szRealString+nWidth-nPrecision+1, 
                pszRawValue+nWidth-nPrecision );
        
        *ppszAttValue = szRealString;
    }

/* -------------------------------------------------------------------- */
/*      If it is an integer, we just reformat to get rid of leading     */
/*      zeros.                                                          */
/* -------------------------------------------------------------------- */
    else if( psAttDesc->finter[0] == 'I' )
    {
        static char    szIntString[30];

        sprintf( szIntString, "%d", atoi(pszRawValue) );

        *ppszAttValue = szIntString;
    }

/* -------------------------------------------------------------------- */
/*      Otherwise we take the value directly.                           */
/* -------------------------------------------------------------------- */
    else
    {
        *ppszAttValue = (char *) pszRawValue;
    }

/* -------------------------------------------------------------------- */
/*      Handle processing code values into code descriptions, if        */
/*      applicable.                                                     */
/* -------------------------------------------------------------------- */
    if( ppszCodeDesc == NULL )
    {
    }
    else if( psAttDesc->poCodeList != NULL )
    {
        *ppszCodeDesc = (char *)psAttDesc->poCodeList->Lookup( *ppszAttValue );
    }
    else
    {
        *ppszCodeDesc = NULL;
    }

    return TRUE;
}

/************************************************************************/
/*                        ApplyAttributeValues()                        */
/*                                                                      */
/*      Apply a series of attribute values to a feature from generic    */
/*      attribute records.                                              */
/************************************************************************/

void NTFFileReader::ApplyAttributeValues( OGRFeature * poFeature,
                                          NTFRecord ** papoGroup, ... )

{
    char        **papszTypes = NULL, **papszValues = NULL;

/* -------------------------------------------------------------------- */
/*      Extract attribute values from record group.                     */
/* -------------------------------------------------------------------- */
    if( !ProcessAttRecGroup( papoGroup, &papszTypes, &papszValues ) )
        return;
    
/* -------------------------------------------------------------------- */
/*      Handle attribute pairs                                          */
/* -------------------------------------------------------------------- */
    va_list     hVaArgs;
    const char  *pszAttName;
    
    va_start(hVaArgs, papoGroup);

    while( (pszAttName = va_arg(hVaArgs, const char *)) != NULL )
    {
        int     iField = va_arg(hVaArgs, int);

        ApplyAttributeValue( poFeature, iField, pszAttName,