ogrgeometryfactory.cpp

mitab,读取MapInfo的地图文件

/******************************************************************************
 * $Id: ogrgeometryfactory.cpp 10646 2007-01-18 02:38:10Z warmerdam $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  Factory for converting geometry to and from well known binary
 *           format.
 * 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_api.h"
#include "ogr_p.h"
#include <assert.h>
#include "ogr_geos.h"

CPL_CVSID("$Id: ogrgeometryfactory.cpp 10646 2007-01-18 02:38:10Z warmerdam $");

/************************************************************************/
/*                           createFromWkb()                            */
/************************************************************************/

/**
 * Create a geometry object of the appropriate type from it's well known
 * binary representation.
 *
 * Note that if nBytes is passed as zero, no checking can be done on whether
 * the pabyData is sufficient.  This can result in a crash if the input
 * data is corrupt.  This function returns no indication of the number of
 * bytes from the data source actually used to represent the returned
 * geometry object.  Use OGRGeometry::WkbSize() on the returned geometry to
 * establish the number of bytes it required in WKB format.
 *
 * Also note that this is a static method, and that there
 * is no need to instantiate an OGRGeometryFactory object.  
 *
 * The C function OGR_G_CreateFromWkb() is the same as this method.
 *
 * @param pabyData pointer to the input BLOB data.
 * @param poSR pointer to the spatial reference to be assigned to the
 *             created geometry object.  This may be NULL.
 * @param ppoReturn the newly created geometry object will be assigned to the
 *                  indicated pointer on return.  This will be NULL in case
 *                  of failure.
 * @param nBytes the number of bytes available in pabyData, or -1 if it isn't
 *               known.
 *
 * @return OGRERR_NONE if all goes well, otherwise any of
 * OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or
 * OGRERR_CORRUPT_DATA may be returned.
 */

OGRErr OGRGeometryFactory::createFromWkb(unsigned char *pabyData,
                                         OGRSpatialReference * poSR,
                                         OGRGeometry **ppoReturn,
                                         int nBytes )

{
    OGRwkbGeometryType eGeometryType;
    OGRwkbByteOrder eByteOrder;
    OGRErr      eErr;
    OGRGeometry *poGeom;

    *ppoReturn = NULL;

    if( nBytes < 5 && nBytes != -1 )
        return OGRERR_NOT_ENOUGH_DATA;

/* -------------------------------------------------------------------- */
/*      Get the byte order byte.  The extra tests are to work around    */
/*      bug sin the WKB of DB2 v7.2 as identified by Safe Software.     */
/* -------------------------------------------------------------------- */
    eByteOrder = DB2_V72_FIX_BYTE_ORDER((OGRwkbByteOrder) *pabyData);


    if( eByteOrder != wkbXDR && eByteOrder != wkbNDR )
    {
        CPLDebug( "OGR", 
                  "OGRGeometryFactory::createFromWkb() - got corrupt data.\n"
                  "%02X%02X%02X%02X%02X%02X%02X%02X\n", 
                  pabyData[0],
                  pabyData[1],
                  pabyData[2],
                  pabyData[3],
                  pabyData[4],
                  pabyData[5],
                  pabyData[6],
                  pabyData[7],
                  pabyData[8] );
        return OGRERR_CORRUPT_DATA;
    }

/* -------------------------------------------------------------------- */
/*      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.                                                       */
/* -------------------------------------------------------------------- */
    if( eByteOrder == wkbNDR )
        eGeometryType = (OGRwkbGeometryType) pabyData[1];
    else
        eGeometryType = (OGRwkbGeometryType) pabyData[4];

/* -------------------------------------------------------------------- */
/*      Instantiate a geometry of the appropriate type, and             */
/*      initialize from the input stream.                               */
/* -------------------------------------------------------------------- */
    poGeom = createGeometry( eGeometryType );
    
    if( poGeom == NULL )
        return OGRERR_UNSUPPORTED_GEOMETRY_TYPE;

/* -------------------------------------------------------------------- */
/*      Import from binary.                                             */
/* -------------------------------------------------------------------- */
    eErr = poGeom->importFromWkb( pabyData, nBytes );

/* -------------------------------------------------------------------- */
/*      Assign spatial reference system.                                */
/* -------------------------------------------------------------------- */
    if( eErr == OGRERR_NONE )
    {
        poGeom->assignSpatialReference( poSR );
        *ppoReturn = poGeom;
    }
    else
    {
        delete poGeom;
    }

    return eErr;
}

/************************************************************************/
/*                        OGR_G_CreateFromWkb()                         */
/************************************************************************/
/**
 * Create a geometry object of the appropriate type from it's well known
 * binary representation.
 *
 * Note that if nBytes is passed as zero, no checking can be done on whether
 * the pabyData is sufficient.  This can result in a crash if the input
 * data is corrupt.  This function returns no indication of the number of
 * bytes from the data source actually used to represent the returned
 * geometry object.  Use OGR_G_WkbSize() on the returned geometry to
 * establish the number of bytes it required in WKB format.
 *
 * The OGRGeometryFactory::createFromWkb() CPP method  is the same as this
 * function.
 *
 * @param pabyData pointer to the input BLOB data.
 * @param hSRS handle to the spatial reference to be assigned to the
 *             created geometry object.  This may be NULL.
 * @param phGeometry the newly created geometry object will 
 * be assigned to the indicated handle on return.  This will be NULL in case
 * of failure.
 * @param nBytes the number of bytes of data available in pabyData, or -1
 * if it is not known, but assumed to be sufficient.
 *
 * @return OGRERR_NONE if all goes well, otherwise any of
 * OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or
 * OGRERR_CORRUPT_DATA may be returned.
 */

OGRErr CPL_DLL OGR_G_CreateFromWkb( unsigned char *pabyData, 
                                    OGRSpatialReferenceH hSRS,
                                    OGRGeometryH *phGeometry, 
                                    int nBytes )

{
    return OGRGeometryFactory::createFromWkb( pabyData, 
                                              (OGRSpatialReference *) hSRS,
                                              (OGRGeometry **) phGeometry,
                                              nBytes );
}

/************************************************************************/
/*                           createFromWkt()                            */
/************************************************************************/

/**
 * Create a geometry object of the appropriate type from it's well known
 * text representation.
 *
 * The C function OGR_G_CreateFromWkt() is the same as this method.
 *
 * @param ppszData input zero terminated string containing well known text
 *                representation of the geometry to be created.  The pointer
 *                is updated to point just beyond that last character consumed.
 * @param poSR pointer to the spatial reference to be assigned to the
 *             created geometry object.  This may be NULL.
 * @param ppoReturn the newly created geometry object will be assigned to the
 *                  indicated pointer on return.  This will be NULL if the
 *                  method fails. 
 *
 *  <b>Example:</b>
 *
 *  <pre>
 *    const char* wkt= "POINT(0 0)";
 *  
 *    // cast because OGR_G_CreateFromWkt will move the pointer 
 *    char* pszWkt = (char*) wkt.c_str(); 
 *    OGRSpatialReferenceH ref = OSRNewSpatialReference(NULL);
 *    OGRGeometryH new_geom;
 *    OGRErr err = OGR_G_CreateFromWkt(&pszWkt, ref, &new_geom);
 *  </pre>
 *
 *
 *
 * @return OGRERR_NONE if all goes well, otherwise any of
 * OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or
 * OGRERR_CORRUPT_DATA may be returned.
 */

OGRErr OGRGeometryFactory::createFromWkt(char **ppszData,
                                         OGRSpatialReference * poSR,
                                         OGRGeometry **ppoReturn )

{
    OGRErr      eErr;
    char        szToken[OGR_WKT_TOKEN_MAX];
    char        *pszInput = *ppszData;
    OGRGeometry *poGeom;

    *ppoReturn = NULL;

/* -------------------------------------------------------------------- */
/*      Get the first token, which should be the geometry type.         */
/* -------------------------------------------------------------------- */
    if( OGRWktReadToken( pszInput, szToken ) == NULL )
        return OGRERR_CORRUPT_DATA;

/* -------------------------------------------------------------------- */
/*      Instantiate a geometry of the appropriate type.                 */
/* -------------------------------------------------------------------- */
    if( EQUAL(szToken,"POINT") )
    {
        poGeom = new OGRPoint();
    }

    else if( EQUAL(szToken,"LINESTRING") )
    {
        poGeom = new OGRLineString();
    }

    else if( EQUAL(szToken,"POLYGON") )
    {
        poGeom = new OGRPolygon();
    }
    
    else if( EQUAL(szToken,"GEOMETRYCOLLECTION") )
    {
        poGeom = new OGRGeometryCollection();
    }
    
    else if( EQUAL(szToken,"MULTIPOLYGON") )
    {
        poGeom = new OGRMultiPolygon();
    }

    else if( EQUAL(szToken,"MULTIPOINT") )
    {
        poGeom = new OGRMultiPoint();
    }

    else if( EQUAL(szToken,"MULTILINESTRING") )
    {
        poGeom = new OGRMultiLineString();
    }

    else
    {
        return OGRERR_UNSUPPORTED_GEOMETRY_TYPE;
    }

/* -------------------------------------------------------------------- */
/*      Do the import.                                                  */
/* -------------------------------------------------------------------- */
    eErr = poGeom->importFromWkt( &pszInput );
    
/* -------------------------------------------------------------------- */
/*      Assign spatial reference system.                                */
/* -------------------------------------------------------------------- */
    if( eErr == OGRERR_NONE )
    {
        poGeom->assignSpatialReference( poSR );
        *ppoReturn = poGeom;
        *ppszData = pszInput;
    }
    else
    {
        delete poGeom;
    }
    
    return eErr;
}

/************************************************************************/
/*                        OGR_G_CreateFromWkt()                         */
/************************************************************************/
/**
 * Create a geometry object of the appropriate type from it's well known
 * text representation.
 *
 * The OGRGeometryFactory::createFromWkt CPP method is the same as this
 * function.
 *
 * @param ppszData input zero terminated string containing well known text
 *                representation of the geometry to be created.  The pointer
 *                is updated to point just beyond that last character consumed.
 * @param hSRS handle to the spatial reference to be assigned to the
 *             created geometry object.  This may be NULL.
 * @param phGeometry the newly created geometry object will be assigned to the
 *                  indicated handle on return.  This will be NULL if the
 *                  method fails. 
 *
 * @return OGRERR_NONE if all goes well, otherwise any of
 * OGRERR_NOT_ENOUGH_DATA, OGRERR_UNSUPPORTED_GEOMETRY_TYPE, or
 * OGRERR_CORRUPT_DATA may be returned.
 */

OGRErr CPL_DLL OGR_G_CreateFromWkt( char **ppszData, 
                                    OGRSpatialReferenceH hSRS,
                                    OGRGeometryH *phGeometry )

{
    return OGRGeometryFactory::createFromWkt( ppszData,
                                              (OGRSpatialReference *) hSRS,
                                              (OGRGeometry **) phGeometry );
}

/************************************************************************/
/*                           createGeometry()                           */
/************************************************************************/

/** 
 * Create an empty geometry of desired type.
 *
 * This is equivelent to allocating the desired geometry with new, but
 * the allocation is guaranteed to take place in the context of the 
 * GDAL/OGR heap. 
 *
 * This method is the same as the C function OGR_G_CreateGeometry().
 *
 * @param eGeometryType the type code of the geometry class to be instantiated.
 *
 * @return the newly create geometry or NULL on failure.
 */

OGRGeometry *
OGRGeometryFactory::createGeometry( OGRwkbGeometryType eGeometryType )

{
    switch( wkbFlatten(eGeometryType) )
    {
      case wkbPoint:
          return new OGRPoint();

      case wkbLineString:
          return new OGRLineString();

      case wkbPolygon:
          return new OGRPolygon();

      case wkbGeometryCollection:
          return new OGRGeometryCollection();

      case wkbMultiPolygon:
          return new OGRMultiPolygon();

      case wkbMultiPoint:
          return new OGRMultiPoint();

      case wkbMultiLineString:
          return new OGRMultiLineString();

      case wkbLinearRing:
          return new OGRLinearRing();

      default:
          return NULL;
    }

    return NULL;
}

/************************************************************************/
/*                        OGR_G_CreateGeometry()                        */
/************************************************************************/
/** 
 * Create an empty geometry of desired type.