ogrgeometrycollection.cpp

mitab,读取MapInfo的地图文件

/******************************************************************************
 * $Id: ogrgeometrycollection.cpp 10646 2007-01-18 02:38:10Z warmerdam $
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  The OGRGeometryCollection 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: ogrgeometrycollection.cpp 10646 2007-01-18 02:38:10Z warmerdam $");

/************************************************************************/
/*                       OGRGeometryCollection()                        */
/************************************************************************/

/**
 * Create an empty geometry collection.
 */

OGRGeometryCollection::OGRGeometryCollection()

{
    nGeomCount = 0;
    papoGeoms = NULL;
    nCoordinateDimension = 2;
}

/************************************************************************/
/*                       ~OGRGeometryCollection()                       */
/************************************************************************/

OGRGeometryCollection::~OGRGeometryCollection()

{
    empty();
    nCoordinateDimension = 2;
}

/************************************************************************/
/*                               empty()                                */
/************************************************************************/

void OGRGeometryCollection::empty()

{
    if( papoGeoms != NULL )
    {
        for( int i = 0; i < nGeomCount; i++ )
        {
            delete papoGeoms[i];
        }
        OGRFree( papoGeoms );
    }

    nGeomCount = 0;
    papoGeoms = NULL;
}


/************************************************************************/
/*                               clone()                                */
/************************************************************************/

OGRGeometry *OGRGeometryCollection::clone() const

{
    OGRGeometryCollection       *poNewGC;

    poNewGC = new OGRGeometryCollection;
    poNewGC->assignSpatialReference( getSpatialReference() );

    for( int i = 0; i < nGeomCount; i++ )
    {
        poNewGC->addGeometry( papoGeoms[i] );
    }

    return poNewGC;
}

/************************************************************************/
/*                          getGeometryType()                           */
/************************************************************************/

OGRwkbGeometryType OGRGeometryCollection::getGeometryType() const

{
    if( getCoordinateDimension() == 3 )
        return wkbGeometryCollection25D;
    else
        return wkbGeometryCollection;
}

/************************************************************************/
/*                            getDimension()                            */
/************************************************************************/

int OGRGeometryCollection::getDimension() const

{
    return 2; // This isn't strictly correct.  It should be based on members.
}

/************************************************************************/
/*                            flattenTo2D()                             */
/************************************************************************/

void OGRGeometryCollection::flattenTo2D()

{
    for( int i = 0; i < nGeomCount; i++ )
        papoGeoms[i]->flattenTo2D();

    nCoordinateDimension = 2;
}

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

const char * OGRGeometryCollection::getGeometryName() const

{
    return "GEOMETRYCOLLECTION";
}

/************************************************************************/
/*                          getNumGeometries()                          */
/************************************************************************/

/**
 * Fetch number of geometries in container.
 *
 * This method relates to the SFCOM IGeometryCollect::get_NumGeometries()
 * method.
 *
 * @return count of children geometries.  May be zero.
 */

int OGRGeometryCollection::getNumGeometries() const

{
    return nGeomCount;
}

/************************************************************************/
/*                           getGeometryRef()                           */
/************************************************************************/

/**
 * Fetch geometry from container.
 *
 * This method returns a pointer to an geometry within the container.  The
 * returned geometry remains owned by the container, and should not be
 * modified.  The pointer is only valid untill the next change to the
 * geometry container.  Use IGeometry::clone() to make a copy.
 *
 * This method relates to the SFCOM IGeometryCollection::get_Geometry() method.
 *
 * @param i the index of the geometry to fetch, between 0 and
 *          getNumGeometries() - 1.
 * @return pointer to requested geometry.
 */

OGRGeometry * OGRGeometryCollection::getGeometryRef( int i ) 

{
    if( i < 0 || i >= nGeomCount )
        return NULL;
    else
        return papoGeoms[i];
}

const OGRGeometry * OGRGeometryCollection::getGeometryRef( int i ) const

{
    if( i < 0 || i >= nGeomCount )
        return NULL;
    else
        return papoGeoms[i];
}

/************************************************************************/
/*                            addGeometry()                             */
/*                                                                      */
/*      Add a new geometry to a collection.  Subclasses should          */
/*      override this to verify the type of the new geometry, and       */
/*      then call this method to actually add it.                       */
/************************************************************************/

/**
 * Add a geometry to the container.
 *
 * Some subclasses of OGRGeometryCollection restrict the types of geometry
 * that can be added, and may return an error.  The passed geometry is cloned
 * to make an internal copy.
 *
 * There is no SFCOM analog to this method.
 *
 * This method is the same as the C function OGR_G_AddGeometry().
 *
 * @param poNewGeom geometry to add to the container.
 *
 * @return OGRERR_NONE if successful, or OGRERR_UNSUPPORTED_GEOMETRY_TYPE if
 * the geometry type is illegal for the type of geometry container.
 */

OGRErr OGRGeometryCollection::addGeometry( const OGRGeometry * poNewGeom )

{
    OGRGeometry *poClone = poNewGeom->clone();
    OGRErr      eErr;

    eErr = addGeometryDirectly( poClone );
    if( eErr != OGRERR_NONE )
        delete poClone;

    return eErr;
}

/************************************************************************/
/*                        addGeometryDirectly()                         */
/*                                                                      */
/*      Add a new geometry to a collection.  Subclasses should          */
/*      override this to verify the type of the new geometry, and       */
/*      then call this method to actually add it.                       */
/************************************************************************/

/**
 * Add a geometry directly to the container.
 *
 * Some subclasses of OGRGeometryCollection restrict the types of geometry
 * that can be added, and may return an error.  Ownership of the passed
 * geometry is taken by the container rather than cloning as addGeometry()
 * does.
 *
 * This method is the same as the C function OGR_G_AddGeometryDirectly().
 *
 * There is no SFCOM analog to this method.
 *
 * @param poNewGeom geometry to add to the container.
 *
 * @return OGRERR_NONE if successful, or OGRERR_UNSUPPORTED_GEOMETRY_TYPE if
 * the geometry type is illegal for the type of geometry container.
 */

OGRErr OGRGeometryCollection::addGeometryDirectly( OGRGeometry * poNewGeom )

{
    papoGeoms = (OGRGeometry **) OGRRealloc( papoGeoms,
                                             sizeof(void*) * (nGeomCount+1) );

    papoGeoms[nGeomCount] = poNewGeom;

    nGeomCount++;

    if( poNewGeom->getCoordinateDimension() == 3 )
        nCoordinateDimension = 3;

    return OGRERR_NONE;
}

/************************************************************************/
/*                           removeGeometry()                           */
/************************************************************************/

/**
 * Remove a geometry from the container.
 *
 * Removing a geometry will cause the geometry count to drop by one, and all
 * "higher" geometries will shuffle down one in index.
 *
 * There is no SFCOM analog to this method.
 *
 * This method is the same as the C function OGR_G_RemoveGeometry().
 *
 * @param iGeom the index of the geometry to delete.  A value of -1 is a
 * special flag meaning that all geometries should be removed.
 *
 * @param bDelete if TRUE the geometry will be deallocated, otherwise it will
 * not.  The default is TRUE as the container is considered to own the
 * geometries in it. 
 *
 * @return OGRERR_NONE if successful, or OGRERR_FAILURE if the index is
 * out of range.
 */

OGRErr OGRGeometryCollection::removeGeometry( int iGeom, int bDelete )

{
    if( iGeom < -1 || iGeom >= nGeomCount )
        return OGRERR_FAILURE;

    // Special case.
    if( iGeom == -1 )
    {
        while( nGeomCount > 0 )
            removeGeometry( nGeomCount-1, bDelete );
        return OGRERR_NONE;
    }

    if( bDelete )
        delete papoGeoms[iGeom];

    memmove( papoGeoms + iGeom, papoGeoms + iGeom + 1, 
             sizeof(void*) * (nGeomCount-iGeom-1) );

    nGeomCount--;

    return OGRERR_NONE;
}

/************************************************************************/
/*                              WkbSize()                               */
/*                                                                      */
/*      Return the size of this object in well known binary             */
/*      representation including the byte order, and type information.  */
/************************************************************************/

int OGRGeometryCollection::WkbSize() const

{
    int         nSize = 9;

    for( int i = 0; i < nGeomCount; i++ )
    {
        nSize += papoGeoms[i]->WkbSize();
    }

    return nSize;
}

/************************************************************************/
/*                           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?              */