ntffilereader.cpp

支持各种栅格图像和矢量图像读取的库

/* -------------------------------------------------------------------- */
/*      Loop looking for a group we can translate, and that if          */
/*      needed matches our layer request.                               */
/* -------------------------------------------------------------------- */
    while( TRUE )
    {
        if( GetProductId() == NPC_UNKNOWN && nNTFLevel > 2 )
            papoGroup = GetNextIndexedRecordGroup( apoCGroup + 1 );
        else
            papoGroup = ReadRecordGroup();

        if( papoGroup == NULL )
            break;
        
        poLayer = apoTypeTranslation[papoGroup[0]->GetType()];
        if( poLayer == NULL )
            continue;

        if( poTargetLayer != NULL && poTargetLayer != poLayer )
        {
            CacheLineGeometryInGroup( papoGroup );
            nSavedFeatureId++;
            continue;
        }

        poFeature = poLayer->FeatureTranslate( this, papoGroup );
        if( poFeature == NULL )
        {
            // should this be a real error?
            CPLDebug( "NTF",
                      "FeatureTranslate() failed for a type %d record group\n"
                      "in a %s type file.\n",
                      papoGroup[0]->GetType(),
                      GetProduct() );
        }
        else
            break;
    }

/* -------------------------------------------------------------------- */
/*      If we got a feature, set the TILE_REF on it.                    */
/* -------------------------------------------------------------------- */
    if( poFeature != NULL )
    {
        int             iTileRefField;

        iTileRefField = poLayer->GetLayerDefn()->GetFieldCount()-1;
    
        CPLAssert( EQUAL(poLayer->GetLayerDefn()->GetFieldDefn(iTileRefField)->
                         GetNameRef(), "TILE_REF") );

        poFeature->SetField( iTileRefField, GetTileName() );
        poFeature->SetFID( nSavedFeatureId );

        nSavedFeatureId++;
    }

/* -------------------------------------------------------------------- */
/*      If we got to the end we can establish our feature count for     */
/*      the file.                                                       */
/* -------------------------------------------------------------------- */
    else
    {
        CPLAssert( nFeatureCount == -1
                   || nFeatureCount == nSavedFeatureId - nBaseFeatureId );
        nFeatureCount = nSavedFeatureId - nBaseFeatureId;
    }

    return( poFeature );
}

/************************************************************************/
/*                            TestForLayer()                            */
/*                                                                      */
/*      Return indicator of whether this file contains any features     */
/*      of the indicated layer type.                                    */
/************************************************************************/

int NTFFileReader::TestForLayer( OGRNTFLayer * poLayer )

{
    for( int i = 0; i < 100; i++ )
    {
        if( apoTypeTranslation[i] == poLayer )
            return TRUE;
    }

    return FALSE;
}

/************************************************************************/
/*                            FreshenIndex()                            */
/*                                                                      */
/*      Rebuild the index if it is needed, and currently missing.       */
/************************************************************************/

void NTFFileReader::FreshenIndex()

{
    if( !bIndexBuilt && bIndexNeeded )
        IndexFile();
}

/************************************************************************/
/*                             IndexFile()                              */
/*                                                                      */
/*      Read all records beyond the section header and build an         */
/*      internal index of them.                                         */
/************************************************************************/

void NTFFileReader::IndexFile()

{
    NTFRecord   *poRecord;
    
    Reset();

    DestroyIndex();

    bIndexNeeded = TRUE;
    bIndexBuilt = TRUE;
    bCacheLines = FALSE;

/* -------------------------------------------------------------------- */
/*      Process all records after the section header, and before 99     */
/*      to put them in the index.                                       */
/* -------------------------------------------------------------------- */
    while( (poRecord = ReadRecord()) != NULL && poRecord->GetType() != 99 )
    {
        int     iType = poRecord->GetType();
        int     iId = atoi(poRecord->GetField( 3, 8 ));

        if( iType < 0 || iType >= 100 )
        {
            CPLError( CE_Failure, CPLE_AppDefined, 
                      "Illegal type %d record, skipping.", 
                      iType );
            delete poRecord;
            continue;
        }

/* -------------------------------------------------------------------- */
/*      Grow type specific subindex if needed.                          */
/* -------------------------------------------------------------------- */
        if( anIndexSize[iType] <= iId )
        {
            int nNewSize = MAX(iId+1,anIndexSize[iType] * 2 + 10);

            apapoRecordIndex[iType] = (NTFRecord **)
                CPLRealloc(apapoRecordIndex[iType],
                           sizeof(void *) * nNewSize);

            for( int i = anIndexSize[iType]; i < nNewSize; i++ )
                (apapoRecordIndex[iType])[i] = NULL;

            anIndexSize[iType] = nNewSize;
        }

/* -------------------------------------------------------------------- */
/*      Put record into type specific subindex based on it's id as      */
/*      the key.                                                        */
/* -------------------------------------------------------------------- */
        if( apapoRecordIndex[iType][iId] != NULL )
        {
            CPLDebug( "OGR_NTF", 
                      "Duplicate record with index %d and type %d\n"
                      "in NTFFileReader::IndexFile().",
                      iId, iType );
            delete apapoRecordIndex[iType][iId];
        }
        (apapoRecordIndex[iType])[iId] = poRecord;
    }

    if( poRecord != NULL )
        delete poRecord;
}

/************************************************************************/
/*                            DestroyIndex()                            */
/************************************************************************/

void NTFFileReader::DestroyIndex()

{
    for( int i = 0; i < 100; i++ )
    {
        for( int iId = 0; iId < anIndexSize[i]; iId++ )
        {
            if( (apapoRecordIndex[i])[iId] != NULL )
                delete (apapoRecordIndex[i])[iId];
        }

        CPLFree( apapoRecordIndex[i] );
        apapoRecordIndex[i] = NULL;
        anIndexSize[i] = 0;
    }

    bIndexBuilt = FALSE;
}

/************************************************************************/
/*                          GetIndexedRecord()                          */
/************************************************************************/

NTFRecord * NTFFileReader::GetIndexedRecord( int iType, int iId )

{
    if( (iType < 0 || iType > 99)
        || (iId < 0 || iId >= anIndexSize[iType]) 
        || (apapoRecordIndex[iType])[iId] == NULL )
    {
        /* If NRT_GEOMETRY3D is an acceptable alternative to 2D */
        if( iType == NRT_GEOMETRY )
            return GetIndexedRecord( NRT_GEOMETRY3D, iId );
        else
            return NULL;
    }

    return (apapoRecordIndex[iType])[iId];
}

/************************************************************************/
/*                          AddToIndexGroup()                           */
/************************************************************************/

static void AddToIndexGroup( NTFRecord **papoGroup, NTFRecord * poRecord )

{
    int         i;
    
    for( i = 1; papoGroup[i] != NULL; i++ ) {}

    papoGroup[i] = poRecord;
    papoGroup[i+1] = NULL;
}


/************************************************************************/
/*                     GetNextIndexedRecordGroup()                      */
/************************************************************************/

NTFRecord **NTFFileReader::GetNextIndexedRecordGroup( NTFRecord **
                                                      papoPrevGroup )

{
    int         nPrevType, nPrevId;

/* -------------------------------------------------------------------- */
/*      What was the identify of our previous anchor record?            */
/* -------------------------------------------------------------------- */
    if( papoPrevGroup == NULL || papoPrevGroup[0] == NULL )
    {
        nPrevType = NRT_POINTREC;
        nPrevId = 0;
        FreshenIndex();
    }
    else
    {
        nPrevType = papoPrevGroup[0]->GetType();
        nPrevId = atoi(papoPrevGroup[0]->GetField(3,8));
    }

/* -------------------------------------------------------------------- */
/*      Find the next anchor record.                                    */
/* -------------------------------------------------------------------- */
    NTFRecord   *poAnchor = NULL;
    
    while( nPrevType != 99 && poAnchor == NULL )
    {
        nPrevId++;
        if( nPrevId >= anIndexSize[nPrevType] )
        {
            do
            {
                nPrevType++;
            }
            while( nPrevType != NRT_VTR
                   && nPrevType != NRT_NODEREC
                   && nPrevType != NRT_TEXTREC
                   && nPrevType != NRT_NAMEREC
                   && nPrevType != NRT_COLLECT
                   && nPrevType != NRT_POLYGON
                   && nPrevType != NRT_CPOLY
                   && nPrevType != NRT_POINTREC
                   && nPrevType != NRT_LINEREC );
            
            nPrevId = 0;
        }
        else
        {
            poAnchor = (apapoRecordIndex[nPrevType])[nPrevId];
        }
    }

    if( poAnchor == NULL )
    {
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Build record group depending on type of anchor and what it      */
/*      refers to.                                                      */
/* -------------------------------------------------------------------- */
    apoCGroup[0] = NULL;
    apoCGroup[1] = poAnchor;
    apoCGroup[2] = NULL;

/* -------------------------------------------------------------------- */
/*      Handle POINTREC/LINEREC                                         */
/* -------------------------------------------------------------------- */
    if( poAnchor->GetType() == NRT_POINTREC
         || poAnchor->GetType() == NRT_LINEREC )
    {
        int             nAttCount = 0;
        
        AddToIndexGroup( apoCGroup,
                         GetIndexedRecord( NRT_GEOMETRY,
                                           atoi(poAnchor->GetField(9,14)) ) );

        if( poAnchor->GetLength() >= 16 )
            nAttCount = atoi(poAnchor->GetField(15,16));

        for( int iAtt = 0; iAtt < nAttCount; iAtt++ )
        {
            AddToIndexGroup(
                apoCGroup,
                GetIndexedRecord( NRT_ATTREC,
                                  atoi(poAnchor->GetField(17+6*iAtt,
                                                          22+6*iAtt)) ) );
        }
    }

/* -------------------------------------------------------------------- */
/*      Handle TEXTREC                                                  */
/* -------------------------------------------------------------------- */
    else if( poAnchor->GetType() == NRT_TEXTREC )
    {
        int             nAttCount = 0;
        int             nSelCount = 0;

        // Add all the text position records.
        nSelCount = atoi(poAnchor->GetField(9,10));
        
        for( int iSel = 0; iSel < nSelCount; iSel++ )
        {
            int iStart = 11 + 12*iSel + 6;
            
            AddToIndexGroup(
                apoCGroup,
                GetIndexedRecord( NRT_TEXTPOS,
                                  atoi(poAnchor->GetField(iStart,iStart+5)) ));
        }

        // Add all geometry and TEXR records pointed to by text position
        // records.
        for( int iRec = 1; apoCGroup[iRec] != NULL; iRec++ )
        {
            int         nNumTEXR;
            NTFRecord  *poRecord = apoCGroup[iRec];
            
            if( poRecord->GetType() != NRT_TEXTPOS )