ogrgeometrycollection.cpp

用于读取TAB、MIF、SHP文件的类

}

/************************************************************************/
/*                           importFromWkb()                            */
/*                                                                      */
/*      Initialize from serialized stream in well known binary          */
/*      format.                                                         */
/************************************************************************/

OGRErr OGRGeometryCollection::importFromWkb( unsigned char * pabyData,
                                             int nSize )

{
    OGRwkbByteOrder     eByteOrder;
    int                 nDataOffset;
    
    if( nSize < 9 && nSize != -1 )
        return OGRERR_NOT_ENOUGH_DATA;

/* -------------------------------------------------------------------- */
/*      Get the byte order byte.                                        */
/* -------------------------------------------------------------------- */
    eByteOrder = DB2_V72_FIX_BYTE_ORDER((OGRwkbByteOrder) *pabyData);
    CPLAssert( eByteOrder == wkbXDR || eByteOrder == wkbNDR );

/* -------------------------------------------------------------------- */
/*      Get the geometry feature type.  For now we assume that          */
/*      geometry type is between 0 and 255 so we only have to fetch     */
/*      one byte.                                                       */
/* -------------------------------------------------------------------- */
#ifdef DEBUG
    OGRwkbGeometryType eGeometryType;

    if( eByteOrder == wkbNDR )
    {
        eGeometryType = (OGRwkbGeometryType) pabyData[1];
    }
    else
    {
        eGeometryType = (OGRwkbGeometryType) pabyData[4];
    }

    CPLAssert( eGeometryType == wkbGeometryCollection
               || eGeometryType == wkbMultiPolygon 
               || eGeometryType == wkbMultiLineString 
               || eGeometryType == wkbMultiPoint );
#endif    

/* -------------------------------------------------------------------- */
/*      Do we already have some existing geometry objects?              */
/* -------------------------------------------------------------------- */
    if( nGeomCount != 0 )
    {
        for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
            delete papoGeoms[iGeom];

        OGRFree( papoGeoms );
        papoGeoms = NULL;
    }
    
/* -------------------------------------------------------------------- */
/*      Get the geometry count.                                         */
/* -------------------------------------------------------------------- */
    memcpy( &nGeomCount, pabyData + 5, 4 );
    
    if( OGR_SWAP( eByteOrder ) )
        nGeomCount = CPL_SWAP32(nGeomCount);

    papoGeoms = (OGRGeometry **) OGRMalloc(sizeof(void*) * nGeomCount);

    nDataOffset = 9;
    if( nSize != -1 )
        nSize -= nDataOffset;

    nCoordinateDimension = 0; // unknown

/* -------------------------------------------------------------------- */
/*      Get the Geoms.                                                  */
/* -------------------------------------------------------------------- */
    for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        OGRErr  eErr;

        eErr = OGRGeometryFactory::
            createFromWkb( pabyData + nDataOffset, NULL,
                           papoGeoms + iGeom, nSize );

        if( eErr != OGRERR_NONE )
        {
            nGeomCount = iGeom;
            return eErr;
        }

        if( nSize != -1 )
            nSize -= papoGeoms[iGeom]->WkbSize();

        nDataOffset += papoGeoms[iGeom]->WkbSize();
    }
    
    return OGRERR_NONE;
}

/************************************************************************/
/*                            exportToWkb()                             */
/*                                                                      */
/*      Build a well known binary representation of this object.        */
/************************************************************************/

OGRErr  OGRGeometryCollection::exportToWkb( OGRwkbByteOrder eByteOrder,
                                            unsigned char * pabyData ) const

{
    int         nOffset;
    
/* -------------------------------------------------------------------- */
/*      Set the byte order.                                             */
/* -------------------------------------------------------------------- */
    pabyData[0] = DB2_V72_UNFIX_BYTE_ORDER((unsigned char) eByteOrder);

/* -------------------------------------------------------------------- */
/*      Set the geometry feature type, ensuring that 3D flag is         */
/*      preserved.                                                      */
/* -------------------------------------------------------------------- */
    GUInt32 nGType = getGeometryType();
    
    if( eByteOrder == wkbNDR )
        nGType = CPL_LSBWORD32( nGType );
    else
        nGType = CPL_MSBWORD32( nGType );

    memcpy( pabyData + 1, &nGType, 4 );
    
/* -------------------------------------------------------------------- */
/*      Copy in the raw data.                                           */
/* -------------------------------------------------------------------- */
    if( OGR_SWAP( eByteOrder ) )
    {
        int     nCount;

        nCount = CPL_SWAP32( nGeomCount );
        memcpy( pabyData+5, &nCount, 4 );
    }
    else
    {
        memcpy( pabyData+5, &nGeomCount, 4 );
    }
    
    nOffset = 9;
    
/* ==================================================================== */
/*      Serialize each of the Geoms.                                    */
/* ==================================================================== */
    for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        papoGeoms[iGeom]->exportToWkb( eByteOrder, pabyData + nOffset );

        nOffset += papoGeoms[iGeom]->WkbSize();
    }
    
    return OGRERR_NONE;
}

/************************************************************************/
/*                           importFromWkt()                            */
/************************************************************************/

OGRErr OGRGeometryCollection::importFromWkt( char ** ppszInput )

{

    char        szToken[OGR_WKT_TOKEN_MAX];
    const char  *pszInput = *ppszInput;
    int         iGeom;

/* -------------------------------------------------------------------- */
/*      Clear existing Geoms.                                           */
/* -------------------------------------------------------------------- */
    if( nGeomCount > 0 )
    {
        for( iGeom = 0; iGeom < nGeomCount; iGeom++ )
            delete papoGeoms[iGeom];
        
        nGeomCount = 0;
        CPLFree( papoGeoms );
    }

/* -------------------------------------------------------------------- */
/*      Read and verify the type keyword, and ensure it matches the     */
/*      actual type of this container.                                  */
/* -------------------------------------------------------------------- */
    pszInput = OGRWktReadToken( pszInput, szToken );

    if( !EQUAL(szToken,getGeometryName()) )
        return OGRERR_CORRUPT_DATA;

/* -------------------------------------------------------------------- */
/*      The next character should be a ( indicating the start of the    */
/*      list of objects.                                                */
/* -------------------------------------------------------------------- */
    pszInput = OGRWktReadToken( pszInput, szToken );

    if( EQUAL(szToken,"EMPTY") )
    {
        *ppszInput = (char *) pszInput;
        return OGRERR_NONE;
    }

    if( szToken[0] != '(' )
        return OGRERR_CORRUPT_DATA;

/* -------------------------------------------------------------------- */
/*      If the next token is EMPTY, then verify that we have proper     */
/*      EMPTY format will a trailing closing bracket.                   */
/* -------------------------------------------------------------------- */
    OGRWktReadToken( pszInput, szToken );
    if( EQUAL(szToken,"EMPTY") )
    {
        pszInput = OGRWktReadToken( pszInput, szToken );
        pszInput = OGRWktReadToken( pszInput, szToken );
        
        *ppszInput = (char *) pszInput;

        if( !EQUAL(szToken,")") )
            return OGRERR_CORRUPT_DATA;
        else
            return OGRERR_NONE;
    }

/* ==================================================================== */
/*      Read each subgeometry in turn.                                  */
/* ==================================================================== */
    do
    {
        OGRGeometry *poGeom = NULL;
        OGRErr      eErr;

        eErr = OGRGeometryFactory::createFromWkt( (char **) &pszInput,
                                                  NULL, &poGeom );
        if( eErr != OGRERR_NONE )
            return eErr;

        addGeometryDirectly( poGeom );

/* -------------------------------------------------------------------- */
/*      Read the delimeter following the ring.                          */
/* -------------------------------------------------------------------- */
        
        pszInput = OGRWktReadToken( pszInput, szToken );
        
    } while( szToken[0] == ',' );

/* -------------------------------------------------------------------- */
/*      freak if we don't get a closing bracket.                        */
/* -------------------------------------------------------------------- */
    if( szToken[0] != ')' )
        return OGRERR_CORRUPT_DATA;
    
    *ppszInput = (char *) pszInput;
    
    return OGRERR_NONE;
}

/************************************************************************/
/*                            exportToWkt()                             */
/*                                                                      */
/*      Translate this structure into it's well known text format       */
/*      equivelent.  This could be made alot more CPU efficient!        */
/************************************************************************/

OGRErr OGRGeometryCollection::exportToWkt( char ** ppszDstText ) const

{
    char        **papszGeoms;
    int         iGeom, nCumulativeLength = 0;
    OGRErr      eErr;

    if( getNumGeometries() == 0 )
    {
        *ppszDstText = CPLStrdup("GEOMETRYCOLLECTION EMPTY");
        return OGRERR_NONE;
    }

/* -------------------------------------------------------------------- */
/*      Build a list of strings containing the stuff for each Geom.     */
/* -------------------------------------------------------------------- */
    papszGeoms = (char **) CPLCalloc(sizeof(char *),nGeomCount);

    for( iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        eErr = papoGeoms[iGeom]->exportToWkt( &(papszGeoms[iGeom]) );
        if( eErr != OGRERR_NONE )
            return eErr;

        nCumulativeLength += strlen(papszGeoms[iGeom]);
    }
    
/* -------------------------------------------------------------------- */
/*      Allocate the right amount of space for the aggregated string    */
/* -------------------------------------------------------------------- */
    *ppszDstText = (char *) VSIMalloc(nCumulativeLength + nGeomCount + 23);

    if( *ppszDstText == NULL )
        return OGRERR_NOT_ENOUGH_MEMORY;

/* -------------------------------------------------------------------- */
/*      Build up the string, freeing temporary strings as we go.        */
/* -------------------------------------------------------------------- */
    strcpy( *ppszDstText, getGeometryName() );
    strcat( *ppszDstText, " (" );

    for( iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {                                                           
        if( iGeom > 0 )
            strcat( *ppszDstText, "," );
        
        strcat( *ppszDstText, papszGeoms[iGeom] );
        VSIFree( papszGeoms[iGeom] );
    }

    strcat( *ppszDstText, ")" );

    CPLFree( papszGeoms );

    return OGRERR_NONE;
}

/************************************************************************/
/*                            getEnvelope()                             */
/************************************************************************/

void OGRGeometryCollection::getEnvelope( OGREnvelope * psEnvelope ) const

{
    OGREnvelope         oGeomEnv;
    
    if( nGeomCount == 0 )
        return;

    papoGeoms[0]->getEnvelope( psEnvelope );

    for( int iGeom = 1; iGeom < nGeomCount; iGeom++ )
    {
        papoGeoms[iGeom]->getEnvelope( &oGeomEnv );

        if( psEnvelope->MinX > oGeomEnv.MinX )
            psEnvelope->MinX = oGeomEnv.MinX;
        if( psEnvelope->MinY > oGeomEnv.MinY )
            psEnvelope->MinY = oGeomEnv.MinY;
        if( psEnvelope->MaxX < oGeomEnv.MaxX )
            psEnvelope->MaxX = oGeomEnv.MaxX;
        if( psEnvelope->MaxY < oGeomEnv.MaxY )
            psEnvelope->MaxY = oGeomEnv.MaxY;
    }
}

/************************************************************************/
/*                               Equals()                               */
/************************************************************************/

OGRBoolean OGRGeometryCollection::Equals( OGRGeometry * poOther ) const

{
    OGRGeometryCollection *poOGC = (OGRGeometryCollection *) poOther;

    if( poOGC == this )
        return TRUE;
    
    if( poOther->getGeometryType() != getGeometryType() )
        return FALSE;

    if( getNumGeometries() != poOGC->getNumGeometries() )
        return FALSE;
    
    // we should eventually test the SRS.

    for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        if( !getGeometryRef(iGeom)->Equals(poOGC->getGeometryRef(iGeom)) )
            return FALSE;
    }

    return TRUE;
}

/************************************************************************/
/*                             transform()                              */
/************************************************************************/

OGRErr OGRGeometryCollection::transform( OGRCoordinateTransformation *poCT )

{
#ifdef DISABLE_OGRGEOM_TRANSFORM
    return OGRERR_FAILURE;
#else
    for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        OGRErr  eErr;

        eErr = papoGeoms[iGeom]->transform( poCT );
        if( eErr != OGRERR_NONE )
        {
            if( iGeom != 0 )
            {
                CPLDebug("OGR", 
                         "OGRGeometryCollection::transform() failed for a geometry other\n"
                         "than the first, meaning some geometries are transformed\n"
                         "and some are not!\n" );

                return OGRERR_FAILURE;
            }

            return eErr;
        }
    }

    assignSpatialReference( poCT->GetTargetCS() );

    return OGRERR_NONE;
#endif
}

/************************************************************************/
/*                             closeRings()                             */
/************************************************************************/

void OGRGeometryCollection::closeRings()

{
    for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        if( wkbFlatten(papoGeoms[iGeom]->getGeometryType()) == wkbPolygon )
            ((OGRPolygon *) papoGeoms[iGeom])->closeRings();
    }
}

/************************************************************************/
/*                       setCoordinateDimension()                       */
/************************************************************************/

void OGRGeometryCollection::setCoordinateDimension( int nNewDimension )

{
    for( int iGeom = 0; iGeom < nGeomCount; iGeom++ )
    {
        papoGeoms[iGeom]->setCoordinateDimension( nNewDimension );
    }

    OGRGeometry::setCoordinateDimension( nNewDimension );
}