mitab_imapinfofile.cpp

用于读取TAB、MIF、SHP文件的类

 * to retreive the next OGRFeature.
 **********************************************************************/
OGRFeature *IMapInfoFile::GetNextFeature()
{
    OGRFeature *poFeatureRef;
    OGRGeometry *poGeom;
    int nFeatureId;

    while( (nFeatureId = GetNextFeatureId(m_nCurFeatureId)) != -1 )
    {
        poFeatureRef = GetFeatureRef(nFeatureId);
        if (poFeatureRef == NULL)
            return NULL;
        else if( (m_poFilterGeom == NULL ||
                  ((poGeom = poFeatureRef->GetGeometryRef()) != NULL &&
                   FilterGeometry( poGeom )))
                 && (m_poAttrQuery == NULL
                     || m_poAttrQuery->Evaluate( poFeatureRef )) )
        {
            // Avoid cloning feature... return the copy owned by the class
            CPLAssert(poFeatureRef == m_poCurFeature);
            m_poCurFeature = NULL;  
            return poFeatureRef;
        }
    }
    return NULL;
}

/**********************************************************************
 *                   IMapInfoFile::CreateFeature()
 *
 * Standard OGR CreateFeature implementation.  This methode is used
 * to create a new feature in current dataset 
 **********************************************************************/
OGRErr     IMapInfoFile::CreateFeature(OGRFeature *poFeature)
{
    TABFeature *poTABFeature;
    OGRGeometry   *poGeom;
    OGRwkbGeometryType eGType;
    OGRErr  eErr;
    TABPoint *poTABPointFeature = NULL;
    TABRegion *poTABRegionFeature = NULL;
    TABPolyline *poTABPolylineFeature = NULL;

    /*-----------------------------------------------------------------
     * MITAB won't accept new features unless they are in a type derived
     * from TABFeature... so we have to do our best to map to the right
     * feature type based on the geometry type.
     *----------------------------------------------------------------*/
    poGeom = poFeature->GetGeometryRef();
    if( poGeom != NULL )
        eGType = poGeom->getGeometryType();
    else
        eGType = wkbNone;

    switch( wkbFlatten(eGType) )
    {
      /*-------------------------------------------------------------
       * POINT
       *------------------------------------------------------------*/
      case wkbPoint:
        poTABFeature = new TABPoint(poFeature->GetDefnRef());
        if(poFeature->GetStyleString())
        {
            poTABPointFeature = (TABPoint*)poTABFeature;
            poTABPointFeature->SetSymbolFromStyleString(
                poFeature->GetStyleString());
        }
        break;
      /*-------------------------------------------------------------
       * REGION
       *------------------------------------------------------------*/
      case wkbPolygon:
      case wkbMultiPolygon:
        poTABFeature = new TABRegion(poFeature->GetDefnRef());
        if(poFeature->GetStyleString())
        {
            poTABRegionFeature = (TABRegion*)poTABFeature;
            poTABRegionFeature->SetPenFromStyleString(
                poFeature->GetStyleString());

            poTABRegionFeature->SetBrushFromStyleString(
                poFeature->GetStyleString());
        }
        break;
      /*-------------------------------------------------------------
       * LINE/PLINE/MULTIPLINE
       *------------------------------------------------------------*/
      case wkbLineString:
      case wkbMultiLineString:
        poTABFeature = new TABPolyline(poFeature->GetDefnRef());
        if(poFeature->GetStyleString())
        {
            poTABPolylineFeature = (TABPolyline*)poTABFeature;
            poTABPolylineFeature->SetPenFromStyleString(
                poFeature->GetStyleString());
        }
        break;
      /*-------------------------------------------------------------
       * Collection types that are not directly supported... convert
       * to multiple features in output file through recursive calls.
       *------------------------------------------------------------*/
      case wkbGeometryCollection:
      case wkbMultiPoint:
      {
          OGRErr eStatus = OGRERR_NONE;
          int i;
          OGRGeometryCollection *poColl = (OGRGeometryCollection*)poGeom;
          OGRFeature *poTmpFeature = poFeature->Clone();

          for (i=0; eStatus==OGRERR_NONE && i<poColl->getNumGeometries(); i++)
          {
              poTmpFeature->SetGeometry(poColl->getGeometryRef(i));
              eStatus = CreateFeature(poTmpFeature);
          }
          delete poTmpFeature;
          return eStatus;
        }
        break;
      /*-------------------------------------------------------------
       * Unsupported type.... convert to MapInfo geometry NONE
       *------------------------------------------------------------*/
      case wkbUnknown:
      default:
         poTABFeature = new TABFeature(poFeature->GetDefnRef()); 
        break;
    }

    if( poGeom != NULL )
        poTABFeature->SetGeometryDirectly(poGeom->clone());
    
    for (int i=0; i< poFeature->GetDefnRef()->GetFieldCount();i++)
    {
        poTABFeature->SetField(i,poFeature->GetRawFieldRef( i ));
    }
    

    if (SetFeature(poTABFeature) > -1)
        eErr = OGRERR_NONE;
    else
        eErr = OGRERR_FAILURE;

    delete poTABFeature;
    
    return eErr;
}

/**********************************************************************
 *                   IMapInfoFile::GetFeature()
 *
 * Standard OGR GetFeature implementation.  This methode is used
 * to get the wanted (nFeatureId) feature, a NULL value will be 
 * returned on error.
 **********************************************************************/
OGRFeature *IMapInfoFile::GetFeature(long nFeatureId)
{
    OGRFeature *poFeatureRef;

    poFeatureRef = GetFeatureRef(nFeatureId);
    if (poFeatureRef)
    {
        // Avoid cloning feature... return the copy owned by the class
        CPLAssert(poFeatureRef == m_poCurFeature);
        m_poCurFeature = NULL;  

        return poFeatureRef;
    }
    else
      return NULL;
}

/************************************************************************/
/*                            CreateField()                             */
/*                                                                      */
/*      Create a native field based on a generic OGR definition.        */
/************************************************************************/

OGRErr IMapInfoFile::CreateField( OGRFieldDefn *poField, int bApproxOK )

{
    TABFieldType        eTABType;
    int                 nWidth = poField->GetWidth();

    if( poField->GetType() == OFTInteger )
    {
        eTABType = TABFInteger;
        if( nWidth == 0 )
            nWidth = 12;
    }
    else if( poField->GetType() == OFTReal )
    {
        eTABType = TABFFloat;
        if( nWidth == 0 )
            nWidth = 32;
    }
    else if( poField->GetType() == OFTString )
    {
        eTABType = TABFChar;
        if( nWidth == 0 )
            nWidth = 254;
        else
            nWidth = MIN(254,nWidth);
    }
    else
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "IMapInfoFile::CreateField() called with unsupported field"
                  " type %d.\n"
                  "Note that Mapinfo files don't support list field types.\n",
                  poField->GetType() );

        return OGRERR_FAILURE;
    }

    if( AddFieldNative( poField->GetNameRef(), eTABType,
                        nWidth, poField->GetPrecision() ) > -1 )
        return OGRERR_NONE;
    else
        return OGRERR_FAILURE;
}