ogrlinearring.cpp

mitab,读取MapInfo的地图文件

/******************************************************************************
 * $Id: ogrlinearring.cpp 12517 2007-10-23 15:07:35Z mloskot $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  The OGRLinearRing geometry class.
 * Author:   Frank Warmerdam, [e-mail]
 *
 ******************************************************************************
 * Copyright (c) 1999, Frank Warmerdam
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ****************************************************************************/

#include "ogr_geometry.h"
#include "ogr_p.h"

CPL_CVSID("$Id: ogrlinearring.cpp 12517 2007-10-23 15:07:35Z mloskot $");

/************************************************************************/
/*                           OGRLinearRing()                            */
/************************************************************************/

OGRLinearRing::OGRLinearRing()

{
}

/************************************************************************/
/*                          ~OGRLinearRing()                            */
/************************************************************************/
OGRLinearRing::~OGRLinearRing()

{
}

/************************************************************************/
/*                           OGRLinearRing()                            */
/************************************************************************/

OGRLinearRing::OGRLinearRing( OGRLinearRing * poSrcRing )

{
    if( poSrcRing == NULL )
    {
        CPLDebug( "OGR", "OGRLinearRing::OGRLinearRing(OGRLinearRing*poSrcRing) - passed in ring is NULL!" );
        return;
    }

    setNumPoints( poSrcRing->getNumPoints() );

    memcpy( paoPoints, poSrcRing->paoPoints,
            sizeof(OGRRawPoint) * getNumPoints() );

    if( poSrcRing->padfZ )
    {
        Make3D();
        memcpy( padfZ, poSrcRing->padfZ, sizeof(double) * getNumPoints() );
    }
}

/************************************************************************/
/*                          getGeometryName()                           */
/************************************************************************/

const char * OGRLinearRing::getGeometryName() const 

{
    return "LINEARRING";
}

/************************************************************************/
/*                              WkbSize()                               */
/*                                                                      */
/*      Disable this method.                                            */
/************************************************************************/

int OGRLinearRing::WkbSize() const

{
    return 0;
}

/************************************************************************/
/*                           importFromWkb()                            */
/*                                                                      */
/*      Disable method for this class.                                  */
/************************************************************************/

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

{
    (void) pabyData;
    (void) nSize;

    return OGRERR_UNSUPPORTED_OPERATION;
}

/************************************************************************/
/*                            exportToWkb()                             */
/*                                                                      */
/*      Disable method for this class.                                  */
/************************************************************************/

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

{
    (void) eByteOrder;
    (void) pabyData;

    return OGRERR_UNSUPPORTED_OPERATION;
}

/************************************************************************/
/*                           _importFromWkb()                           */
/*                                                                      */
/*      Helper method for OGRPolygon.  NOT A NORMAL importFromWkb()     */
/*      method!                                                         */
/************************************************************************/

OGRErr OGRLinearRing::_importFromWkb( OGRwkbByteOrder eByteOrder, int b3D, 
                                      unsigned char * pabyData,
                                      int nBytesAvailable ) 

{
    if( nBytesAvailable < 4 && nBytesAvailable != -1 )
        return OGRERR_NOT_ENOUGH_DATA;

/* -------------------------------------------------------------------- */
/*      Get the vertex count.                                           */
/* -------------------------------------------------------------------- */
    int         nNewNumPoints;
    
    memcpy( &nNewNumPoints, pabyData, 4 );
    
    if( OGR_SWAP( eByteOrder ) )
        nNewNumPoints = CPL_SWAP32(nNewNumPoints);

    /* Check if the wkb stream buffer is big enough to store
     * fetched number of points.
     * 16 or 24 - size of point structure
     */
    int nPointSize = (b3D ? 24 : 16);
    int nBufferMinSize = nPointSize * nNewNumPoints;
   
    if( nBufferMinSize > nBytesAvailable && nBytesAvailable > 0 )
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "Length of input WKB is too small" );
        return OGRERR_NOT_ENOUGH_DATA;
    }

    /* (Re)Allocation of paoPoints buffer. */
    setNumPoints( nNewNumPoints );

    if( b3D )
        Make3D();
    else
        Make2D();
    
/* -------------------------------------------------------------------- */
/*      Get the vertices                                                */
/* -------------------------------------------------------------------- */
    int i = 0;
    int nBytesToCopy = 0;

    if( !b3D )
    {
        nBytesToCopy = 16 * nPointCount;
        
        if( nBytesToCopy > nBytesAvailable && nBytesAvailable > 0 )
        {
            CPLError( CE_Failure, CPLE_AppDefined,
                      "WKB buffer with OGRLinearRing points is too small! \
                      \n\tWKB stream may be corrupted or it is EWKB stream which is not supported");
            return OGRERR_NOT_ENOUGH_DATA;
        }

        memcpy( paoPoints, pabyData + 4, nBytesToCopy );
    }
    else
    {
        for( int i = 0; i < nPointCount; i++ )
        {
            nBytesToCopy = 24;

            if( nBytesToCopy > nBytesAvailable && nBytesAvailable > 0 )
            {
                CPLError( CE_Failure, CPLE_AppDefined,
                          "WKB buffer with OGRLinearRing points is too small! \
                          \n\tWKB stream may be corrupted or it is EWKB stream which is not supported");
                return OGRERR_NOT_ENOUGH_DATA;
            }
            if ( nBytesAvailable > 0 )
                nBytesAvailable -= nBytesToCopy;

            memcpy( &(paoPoints[i].x), pabyData + 4 + 24 * i, 8 );
            memcpy( &(paoPoints[i].y), pabyData + 4 + 24 * i + 8, 8 );
            memcpy( padfZ + i, pabyData + 4 + 24 * i + 16, 8 );
        }
    }
    
/* -------------------------------------------------------------------- */
/*      Byte swap if needed.                                            */
/* -------------------------------------------------------------------- */
    if( OGR_SWAP( eByteOrder ) )
    {
        for( i = 0; i < nPointCount; i++ )
        {
            CPL_SWAPDOUBLE( &(paoPoints[i].x) );
            CPL_SWAPDOUBLE( &(paoPoints[i].y) );

            if( b3D )
            {
                CPL_SWAPDOUBLE( padfZ + i );
            }
        }
    }

    return OGRERR_NONE;
}

/************************************************************************/
/*                            _exportToWkb()                            */
/*                                                                      */
/*      Helper method for OGRPolygon.  THIS IS NOT THE NORMAL           */
/*      exportToWkb() METHOD!                                           */
/************************************************************************/

OGRErr  OGRLinearRing::_exportToWkb( OGRwkbByteOrder eByteOrder, int b3D,
                                     unsigned char * pabyData ) const

{
    int   i, nWords;