mitab_tabseamless.cpp

mitab,读取MapInfo的地图文件

    return -1;
}

/**********************************************************************
 *                   TABSeamless::GetFeatureRef()
 *
 * Fill and return a TABFeature object for the specified feature id.
 *
 * The returned pointer is a reference to an object owned and maintained
 * by this TABSeamless object.  It should not be altered or freed by the 
 * caller and its contents is guaranteed to be valid only until the next
 * call to GetFeatureRef() or Close().
 *
 * Returns NULL if the specified feature id does not exist of if an
 * error happened.  In any case, CPLError() will have been called to
 * report the reason of the failure.
 **********************************************************************/
TABFeature *TABSeamless::GetFeatureRef(int nFeatureId)
{
    if (m_poIndexTable == NULL)
        return NULL; // File is not opened yet

    if (nFeatureId == m_nCurFeatureId && m_poCurFeature)
        return m_poCurFeature;

    if (m_nCurBaseTableId != ExtractBaseTableId(nFeatureId))
    {
        if (OpenBaseTable(ExtractBaseTableId(nFeatureId)) != 0)
            return NULL;
    }

    if (m_poCurBaseTable)
    {
        if (m_poCurFeature)
            delete m_poCurFeature;

        m_poCurFeature = (TABFeature*)m_poCurBaseTable->GetFeature(ExtractBaseFeatureId(nFeatureId));
        m_nCurFeatureId = nFeatureId;

        m_poCurFeature->SetFID(nFeatureId);

        return m_poCurFeature;
    }

    return NULL;
}


/**********************************************************************
 *                   TABSeamless::GetLayerDefn()
 *
 * Returns a reference to the OGRFeatureDefn that will be used to create
 * features in this dataset.
 *
 * Returns a reference to an object that is maintained by this TABSeamless
 * object (and thus should not be modified or freed by the caller) or
 * NULL if the OGRFeatureDefn has not been initialized yet (i.e. no file
 * opened yet)
 **********************************************************************/
OGRFeatureDefn *TABSeamless::GetLayerDefn()
{
    return m_poFeatureDefnRef;
}

/**********************************************************************
 *                   TABSeamless::GetNativeFieldType()
 *
 * Returns the native MapInfo field type for the specified field.
 *
 * Returns TABFUnknown if file is not opened, or if specified field index is
 * invalid.
 *
 * Note that field ids are positive and start at 0.
 **********************************************************************/
TABFieldType TABSeamless::GetNativeFieldType(int nFieldId)
{
    if (m_poCurBaseTable)
        return m_poCurBaseTable->GetNativeFieldType(nFieldId);

    return TABFUnknown;
}



/**********************************************************************
 *                   TABSeamless::IsFieldIndexed()
 *
 * Returns TRUE if field is indexed, or FALSE otherwise.
 **********************************************************************/
GBool TABSeamless::IsFieldIndexed(int nFieldId)
{
    if (m_poCurBaseTable)
        return m_poCurBaseTable->IsFieldIndexed(nFieldId);

    return FALSE;
}

/**********************************************************************
 *                   TABSeamless::IsFieldUnique()
 *
 * Returns TRUE if field is in the Unique table, or FALSE otherwise.
 **********************************************************************/
GBool TABSeamless::IsFieldUnique(int nFieldId)
{
    if (m_poCurBaseTable)
        return m_poCurBaseTable->IsFieldUnique(nFieldId);

    return FALSE;
}


/**********************************************************************
 *                   TABSeamless::GetBounds()
 *
 * Fetch projection coordinates bounds of a dataset.
 *
 * The bForce flag has no effect on TAB files since the bounds are
 * always in the header.
 *
 * Returns 0 on success, -1 on error.
 **********************************************************************/
int TABSeamless::GetBounds(double &dXMin, double &dYMin, 
                       double &dXMax, double &dYMax,
                       GBool bForce /*= TRUE*/)
{
    if (m_poIndexTable == NULL)
    {
        CPLError(CE_Failure, CPLE_AppDefined,
             "GetBounds() can be called only after dataset has been opened.");
        return -1;
    }

    return m_poIndexTable->GetBounds(dXMin, dYMin, dXMax, dYMax, bForce);
}

/**********************************************************************
 *                   TABSeamless::GetExtent()
 *
 * Fetch extent of the data currently stored in the dataset.
 *
 * The bForce flag has no effect on TAB files since that value is
 * always in the header.
 *
 * Returns OGRERR_NONE/OGRRERR_FAILURE.
 **********************************************************************/
OGRErr TABSeamless::GetExtent (OGREnvelope *psExtent, int bForce)
{
    if (m_poIndexTable == NULL)
    {
        CPLError(CE_Failure, CPLE_AppDefined,
             "GetExtent() can be called only after dataset has been opened.");
        return OGRERR_FAILURE;
    }

    return m_poIndexTable->GetExtent(psExtent, bForce);

}

/**********************************************************************
 *                   TABSeamless::GetFeatureCountByType()
 *
 * Return number of features of each type.
 *
 * Note that the sum of the 4 returned values may be different from
 * the total number of features since features with NONE geometry
 * are not taken into account here.
 *
 * Returns 0 on success, or silently returns -1 (with no error) if this
 * information is not available.
 **********************************************************************/
int TABSeamless::GetFeatureCountByType(int &numPoints, int &numLines,
                                   int &numRegions, int &numTexts,
                                   GBool bForce /*= TRUE*/)
{
    /*-----------------------------------------------------------------
     * __TODO__  This should be implemented to return -1 if force=false,
     * or scan all the base tables if force=true
     *----------------------------------------------------------------*/

    return -1;
}

int TABSeamless::GetFeatureCount(int bForce)
{
    /*-----------------------------------------------------------------
     * __TODO__  This should be implemented to return -1 if force=false,
     * or scan all the base tables if force=true
     *----------------------------------------------------------------*/

    return OGRLayer::GetFeatureCount(bForce);
}


/**********************************************************************
 *                   TABSeamless::GetSpatialRef()
 *
 * Returns a reference to an OGRSpatialReference for this dataset.
 * If the projection parameters have not been parsed yet, then we will
 * parse them before returning.
 *
 * The returned object is owned and maintained by this TABFile and
 * should not be modified or freed by the caller.
 *
 * Returns NULL if the SpatialRef cannot be accessed.
 **********************************************************************/
OGRSpatialReference *TABSeamless::GetSpatialRef()
{
    if (m_poIndexTable == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
                 "GetSpatialRef() failed: file has not been opened yet.");
        return NULL;
    }

    return m_poIndexTable->GetSpatialRef();
}



/**********************************************************************
 *                   IMapInfoFile::SetSpatialFilter()
 *
 * Standard OGR SetSpatialFiltere implementation.  This methode is used
 * to set a SpatialFilter for this OGRLayer
 **********************************************************************/
void TABSeamless::SetSpatialFilter (OGRGeometry * poGeomIn )

{
    IMapInfoFile::SetSpatialFilter( poGeomIn );

    if( m_poIndexTable )
        m_poIndexTable->SetSpatialFilter( poGeomIn );

    if( m_poCurBaseTable )
        m_poCurBaseTable->SetSpatialFilter( poGeomIn );
}



/************************************************************************/
/*                           TestCapability()                           */
/************************************************************************/

int TABSeamless::TestCapability( const char * pszCap )

{
    if( EQUAL(pszCap,OLCRandomRead) )
        return TRUE;

    else if( EQUAL(pszCap,OLCSequentialWrite) 
             || EQUAL(pszCap,OLCRandomWrite) )
        return FALSE;

    else if( EQUAL(pszCap,OLCFastFeatureCount) )
        return FALSE;

    else if( EQUAL(pszCap,OLCFastSpatialFilter) )
        return FALSE;

    else if( EQUAL(pszCap,OLCFastGetExtent) )
        return TRUE;

    else 
        return FALSE;
}



/**********************************************************************
 *                   TABSeamless::Dump()
 *
 * Dump block contents... available only in DEBUG mode.
 **********************************************************************/
#ifdef DEBUG

void TABSeamless::Dump(FILE *fpOut /*=NULL*/)
{
    if (fpOut == NULL)
        fpOut = stdout;

    fprintf(fpOut, "----- TABSeamless::Dump() -----\n");

    if (m_poIndexTable == NULL)
    {
        fprintf(fpOut, "File is not opened.\n");
    }
    else
    {
        fprintf(fpOut, "File is opened: %s\n", m_pszFname);

    }

    fflush(fpOut);
}

#endif // DEBUG