mitab_feature.cpp

mitab,读取MapInfo的地图文件

 *
 * Return the values for the MBR corners for this feature.
 **********************************************************************/
void TABFeature::GetMBR(double &dXMin, double &dYMin, 
                        double &dXMax, double &dYMax)
{
    dXMin = m_dXMin;
    dYMin = m_dYMin;
    dXMax = m_dXMax;
    dYMax = m_dYMax;
}

/**********************************************************************
 *                   TABFeature::SetIntMBR()
 *
 * Set the integer coordinates values of the MBR of this feature.
 **********************************************************************/
void TABFeature::SetIntMBR(GInt32 nXMin, GInt32 nYMin, 
                           GInt32 nXMax, GInt32 nYMax)
{
    m_nXMin = nXMin;
    m_nYMin = nYMin;
    m_nXMax = nXMax;
    m_nYMax = nYMax;
}

/**********************************************************************
 *                   TABFeature::GetIntMBR()
 *
 * Return the integer coordinates values of the MBR of this feature.
 **********************************************************************/
void TABFeature::GetIntMBR(GInt32 &nXMin, GInt32 &nYMin, 
                           GInt32 &nXMax, GInt32 &nYMax)
{
    nXMin = m_nXMin;
    nYMin = m_nYMin;
    nXMax = m_nXMax;
    nYMax = m_nYMax;
}

/**********************************************************************
 *                   TABFeature::ReadRecordFromDATFile()
 *
 * Fill the fields part of the feature from the contents of the 
 * table record pointed to by poDATFile.
 *
 * It is assumed that poDATFile currently points to the beginning of
 * the table record and that this feature's OGRFeatureDefn has been 
 * properly initialized for this table.
 **********************************************************************/
int TABFeature::ReadRecordFromDATFile(TABDATFile *poDATFile)
{
    int         iField, numFields, nValue;
    double      dValue;
    const char *pszValue;

    CPLAssert(poDATFile);

    numFields = poDATFile->GetNumFields();

    for(iField=0; iField<numFields; iField++)
    {
        switch(poDATFile->GetFieldType(iField))
        {
          case TABFChar:
            pszValue = poDATFile->ReadCharField(poDATFile->
                                                GetFieldWidth(iField));
            SetField(iField, pszValue);
            break;
          case TABFDecimal:
            dValue = poDATFile->ReadDecimalField(poDATFile->
                                                 GetFieldWidth(iField));
            SetField(iField, dValue);
            break;
          case TABFInteger:
            nValue = poDATFile->ReadIntegerField(poDATFile->
                                                 GetFieldWidth(iField));
            SetField(iField, nValue);
            break;
          case TABFSmallInt:
            nValue = poDATFile->ReadSmallIntField(poDATFile->
                                                 GetFieldWidth(iField));
            SetField(iField, nValue);
            break;
          case TABFFloat:
            dValue = poDATFile->ReadFloatField(poDATFile->
                                                 GetFieldWidth(iField));
            SetField(iField, dValue);
            break;
          case TABFLogical:
            pszValue = poDATFile->ReadLogicalField(poDATFile->
                                                 GetFieldWidth(iField));
            SetField(iField, pszValue);
            break;
          case TABFDate:
            pszValue = poDATFile->ReadDateField(poDATFile->
                                                 GetFieldWidth(iField));
            SetField(iField, pszValue);
            break;
          case TABFTime:
            pszValue = poDATFile->ReadTimeField(poDATFile->
                                                GetFieldWidth(iField));
            SetField(iField, pszValue);
            break;
          case TABFDateTime:
            pszValue = poDATFile->ReadDateTimeField(poDATFile->
                                                    GetFieldWidth(iField));
            SetField(iField, pszValue);
            break;
          default:
            // Other type???  Impossible!
            CPLError(CE_Failure, CPLE_AssertionFailed,
                     "Unsupported field type!");
        }

    }

    return 0;
}

/**********************************************************************
 *                   TABFeature::WriteRecordToDATFile()
 *
 * Write the attribute part of the feature to the .DAT file.
 *
 * It is assumed that poDATFile currently points to the beginning of
 * the table record and that this feature's OGRFeatureDefn has been 
 * properly initialized for this table.
 *
 * Returns 0 on success, -1 on error.
 **********************************************************************/
int TABFeature::WriteRecordToDATFile(TABDATFile *poDATFile,
                                     TABINDFile *poINDFile, int *panIndexNo)
{
    int         iField, numFields, nStatus=0;

    CPLAssert(poDATFile);
    CPLAssert(panIndexNo || GetDefnRef()->GetFieldCount() == 0);

    numFields = poDATFile->GetNumFields();

    for(iField=0; nStatus == 0 && iField<numFields; iField++)
    {
        // Hack for "extra" introduced field.
        if( iField >= GetDefnRef()->GetFieldCount() )
        {
            CPLAssert( poDATFile->GetFieldType(iField) == TABFInteger 
                       && iField == 0 );
            nStatus = poDATFile->WriteIntegerField( GetFID(), poINDFile, 0 );
            continue;
        }

        switch(poDATFile->GetFieldType(iField))
        {
          case TABFChar:
            nStatus = poDATFile->WriteCharField(GetFieldAsString(iField),
                                      poDATFile->GetFieldWidth(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFDecimal:
            nStatus = poDATFile->WriteDecimalField(GetFieldAsDouble(iField),
                                      poDATFile->GetFieldWidth(iField),
                                      poDATFile->GetFieldPrecision(iField),
                                             poINDFile, panIndexNo[iField]);
            break;
          case TABFInteger:
            nStatus = poDATFile->WriteIntegerField(GetFieldAsInteger(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFSmallInt:
            nStatus = poDATFile->WriteSmallIntField(GetFieldAsInteger(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFFloat:
            nStatus = poDATFile->WriteFloatField(GetFieldAsDouble(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFLogical:
            nStatus = poDATFile->WriteLogicalField(GetFieldAsString(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFDate:
            nStatus = poDATFile->WriteDateField(GetFieldAsString(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFTime:
            nStatus = poDATFile->WriteTimeField(GetFieldAsString(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          case TABFDateTime:
            nStatus = poDATFile->WriteDateTimeField(GetFieldAsString(iField),
                                                poINDFile, panIndexNo[iField]);
            break;
          default:
            // Other type???  Impossible!
            CPLError(CE_Failure, CPLE_AssertionFailed,
                     "Unsupported field type!");
        }

    }

    if (poDATFile->CommitRecordToFile() != 0)
        return -1;

    return 0;
}

/**********************************************************************
 *                   TABFeature::ReadGeometryFromMAPFile()
 *
 * In derived classes, this method should be reimplemented to
 * fill the geometry and representation (color, etc...) part of the
 * feature from the contents of the .MAP object pointed to by poMAPFile.
 *
 * It is assumed that before calling ReadGeometryFromMAPFile(), poMAPFile
 * currently points to the beginning of a map object.
 *
 * bCoordBlockDataOnly=TRUE is used when this method is called to copy only
 * the CoordBlock data during splitting of object blocks. In this case we
 * need to process only the information related to the CoordBlock. One 
 * important thing to avoid is reading/writing pen/brush/symbol definitions
 * as that would screw up their ref counters.
 *
 * ppoCoordBlock is used by TABCollection and by index splitting code
 * to provide a CoordBlock to use instead of the one from the poMAPFile and
 * return the current pointer at the end of the call.
 *
 * The current implementation does nothing since instances of TABFeature
 * objects contain no geometry (i.e. TAB_GEOM_NONE).
 * 
 * Returns 0 on success, -1 on error, in which case CPLError() will have
 * been called.
 **********************************************************************/
int TABFeature::ReadGeometryFromMAPFile(TABMAPFile * /*poMapFile*/,
                                        TABMAPObjHdr * /*poObjHdr*/,
                                        GBool /*bCoordBlockDataOnly=FALSE*/, 
                                        TABMAPCoordBlock ** /*ppoCoordBlock=NULL*/)
{
    /*-----------------------------------------------------------------
     * Nothing to do... instances of TABFeature objects contain no geometry.
     *----------------------------------------------------------------*/

    return 0;
}


/**********************************************************************
 *                   TABFeature::UpdateMBR()
 *
 * Fetch envelope of poGeom and update MBR.
 * Integer coord MBR is updated only if poMapFile is not NULL.
 *
 * Returns 0 on success, or -1 if there is no geometry in object
 **********************************************************************/
int TABFeature::UpdateMBR(TABMAPFile * poMapFile /*=NULL*/)
{
    OGRGeometry *poGeom;

    poGeom = GetGeometryRef();

    if (poGeom)
    {
        OGREnvelope oEnv;
        poGeom->getEnvelope(&oEnv);

        m_dXMin = oEnv.MinX;
        m_dYMin = oEnv.MinY;
        m_dXMax = oEnv.MaxX;
        m_dYMax = oEnv.MaxY;

        if (poMapFile)
        {
            poMapFile->Coordsys2Int(oEnv.MinX, oEnv.MinY, m_nXMin, m_nYMin);
            poMapFile->Coordsys2Int(oEnv.MaxX, oEnv.MaxY, m_nXMax, m_nYMax);
        }

        return 0;
    }

    return -1;
}

/**********************************************************************
 *                   TABFeature::ValidateCoordType()
 *
 * Checks the feature envelope to establish if the feature should be
 * written using Compressed coordinates or not and adjust m_nMapInfoType
 * accordingly. Calling this method also sets (initializes) m_nXMin, m_nYMin, 
 * m_nXMax, m_nYMax
 *
 * This function should be used only by the ValidateMapInfoType() 
 * implementations.
 *
 * Returns TRUE if coord. should be compressed, FALSE otherwise
 **********************************************************************/
GBool TABFeature::ValidateCoordType(TABMAPFile * poMapFile)
{
    GBool bCompr = FALSE;

    /*-------------------------------------------------------------
     * Decide if coordinates should be compressed or not.
     *------------------------------------------------------------*/
    if (UpdateMBR(poMapFile) == 0)
    {
        /* Test for max range < 65535 here instead of < 65536 to avoid
         * compressed coordinate overflows in some boundary situations
         */
        if ((m_nXMax - m_nXMin) < 65535 && (m_nYMax-m_nYMin) < 65535)
        {
            bCompr = TRUE;
        }
        m_nComprOrgX = (m_nXMin + m_nXMax) / 2;
        m_nComprOrgY = (m_nYMin + m_nYMax) / 2;
    }

    /*-------------------------------------------------------------
     * Adjust native type
     *------------------------------------------------------------*/
    if (bCompr && ((m_nMapInfoType%3) == 2))
        m_nMapInfoType--;  // compr = 1, 4, 7, ...
    else if (!bCompr && ((m_nMapInfoType%3) == 1))
        m_nMapInfoType++;  // non-compr = 2, 5, 8, ...

    return bCompr;
}

/**********************************************************************
 *                   TABFeature::ForceCoordTypeAndOrigin()
 *
 * This function is used by TABCollection::ValidateMapInfoType() to force 
 * the coord type and compressed origin of all members of a collection 
 * to be the same. (A replacement for ValidateCoordType() for this 
 * specific case)
 **********************************************************************/
void TABFeature::ForceCoordTypeAndOrigin(int nMapInfoType, GBool bCompr,
                                         GInt32 nComprOrgX, GInt32 nComprOrgY,
                                         GInt32 nXMin, GInt32 nYMin, 
                                         GInt32 nXMax, GInt32 nYMax)
{
    /*-------------------------------------------------------------
     * Set Compressed Origin and adjust native type