ogr2kmlgeometry.cpp

来自「支持各种栅格图像和矢量图像读取的库」· C++ 代码 · 共 430 行 · 第 1/2 页

        AppendCoordinateList( (OGRLineString *) poGeometry, 
                              ppszText, pnLength, pnMaxLength );
        
        if( bRing )
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</LinearRing>" );
        else
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</LineString>" );
    }

/* -------------------------------------------------------------------- */
/*      Polygon                                                         */
/* -------------------------------------------------------------------- */
    else if( poGeometry->getGeometryType() == wkbPolygon 
             || poGeometry->getGeometryType() == wkbPolygon25D )
    {
        OGRPolygon      *poPolygon = (OGRPolygon *) poGeometry;

        AppendString( ppszText, pnLength, pnMaxLength,
                      "<Polygon>" );

        if( poPolygon->getExteriorRing() != NULL )
        {
            AppendString( ppszText, pnLength, pnMaxLength,
                          "<outerBoundaryIs>" );

            if( !OGR2KMLGeometryAppend( poPolygon->getExteriorRing(), 
                                        ppszText, pnLength, pnMaxLength ) )
                return FALSE;
            
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</outerBoundaryIs>" );
        }

        for( int iRing = 0; iRing < poPolygon->getNumInteriorRings(); iRing++ )
        {
            OGRLinearRing *poRing = poPolygon->getInteriorRing(iRing);

            AppendString( ppszText, pnLength, pnMaxLength,
                          "<innerBoundaryIs>" );
            
            if( !OGR2KMLGeometryAppend( poRing, ppszText, pnLength, 
                                        pnMaxLength ) )
                return FALSE;
            
            AppendString( ppszText, pnLength, pnMaxLength,
                          "</innerBoundaryIs>" );
        }

        AppendString( ppszText, pnLength, pnMaxLength,
                      "</Polygon>" );
    }

/* -------------------------------------------------------------------- */
/*      MultiPolygon                                                    */
/* -------------------------------------------------------------------- */
    else if( wkbFlatten(poGeometry->getGeometryType()) == wkbMultiPolygon 
             || wkbFlatten(poGeometry->getGeometryType()) == wkbMultiLineString
             || wkbFlatten(poGeometry->getGeometryType()) == wkbMultiPoint
             || wkbFlatten(poGeometry->getGeometryType()) == wkbGeometryCollection )
    {
        OGRGeometryCollection *poGC = (OGRGeometryCollection *) poGeometry;
        int             iMember;
        const char *pszElem, *pszMemberElem;

        if( wkbFlatten(poGeometry->getGeometryType()) == wkbMultiPolygon )
        {
            pszElem = "MultiPolygon>";
            pszMemberElem = "polygonMember>";
        }
        else if( wkbFlatten(poGeometry->getGeometryType()) == wkbMultiLineString )
        {
            pszElem = "MultiLineString>";
            pszMemberElem = "lineStringMember>";
        }
        else if( wkbFlatten(poGeometry->getGeometryType()) == wkbMultiPoint )
        {
            pszElem = "MultiPoint>";
            pszMemberElem = "pointMember>";
        }
        else
        {
            pszElem = "GeometryCollection>";
            pszMemberElem = "geometryMember>";
        }

        AppendString( ppszText, pnLength, pnMaxLength, "<" );
        AppendString( ppszText, pnLength, pnMaxLength, pszElem );

        for( iMember = 0; iMember < poGC->getNumGeometries(); iMember++)
        {
            OGRGeometry *poMember = poGC->getGeometryRef( iMember );

            AppendString( ppszText, pnLength, pnMaxLength, "<" );
            AppendString( ppszText, pnLength, pnMaxLength, pszMemberElem );
            
            if( !OGR2KMLGeometryAppend( poMember, 
                                        ppszText, pnLength, pnMaxLength ) )
                return FALSE;
            
            AppendString( ppszText, pnLength, pnMaxLength, "</" );
            AppendString( ppszText, pnLength, pnMaxLength, pszMemberElem );
        }

        AppendString( ppszText, pnLength, pnMaxLength, "</" );
        AppendString( ppszText, pnLength, pnMaxLength, pszElem );
    }

    else
        return FALSE;

    return TRUE;
}

/************************************************************************/
/*                   OGR_G_ExportEnvelopeToKMLTree()                    */
/*                                                                      */
/*      Export the envelope of a geometry as a KML:Box.                 */
/************************************************************************/

CPLXMLNode *OGR_G_ExportEnvelopeToKMLTree( OGRGeometryH hGeometry )
{
    CPLXMLNode *psBox, *psCoord;
    OGREnvelope sEnvelope;
    char        szCoordinate[256];
    char       *pszY;

    memset( &sEnvelope, 0, sizeof(sEnvelope) );
    ((OGRGeometry *) hGeometry)->getEnvelope( &sEnvelope );

    if( sEnvelope.MinX == 0 && sEnvelope.MaxX == 0 
        && sEnvelope.MaxX == 0 && sEnvelope.MaxY == 0 )
    {
        /* there is apparently a special way of representing a null box
           geometry ... we should use it here eventually. */

        return NULL;
    }

    psBox = CPLCreateXMLNode( NULL, CXT_Element, "Box" );

/* -------------------------------------------------------------------- */
/*      Add minxy coordinate.                                           */
/* -------------------------------------------------------------------- */
    psCoord = CPLCreateXMLNode( psBox, CXT_Element, "coord" );
    
    MakeKMLCoordinate( szCoordinate, sEnvelope.MinX, sEnvelope.MinY, 0.0, 
                       FALSE );
    pszY = strstr(szCoordinate,",") + 1;
    pszY[-1] = '\0';

    CPLCreateXMLElementAndValue( psCoord, "X", szCoordinate );
    CPLCreateXMLElementAndValue( psCoord, "Y", pszY );

/* -------------------------------------------------------------------- */
/*      Add maxxy coordinate.                                           */
/* -------------------------------------------------------------------- */
    psCoord = CPLCreateXMLNode( psBox, CXT_Element, "coord" );
    
    MakeKMLCoordinate( szCoordinate, sEnvelope.MaxX, sEnvelope.MaxY, 0.0, 
                       FALSE );
    pszY = strstr(szCoordinate,",") + 1;
    pszY[-1] = '\0';

    CPLCreateXMLElementAndValue( psCoord, "X", szCoordinate );
    CPLCreateXMLElementAndValue( psCoord, "Y", pszY );

    return psBox;
}

/************************************************************************/
/*                         OGR_G_ExportToKML()                          */
/************************************************************************/
char *OGR_G_ExportToKML( OGRGeometryH hGeometry )
{
    char        *pszText;
    int         nLength = 0, nMaxLength = 1;

    if( hGeometry == NULL )
        return CPLStrdup( "" );

    pszText = (char *) CPLMalloc(nMaxLength);
    pszText[0] = '\0';

    if( !OGR2KMLGeometryAppend( (OGRGeometry *) hGeometry, &pszText, 
                                &nLength, &nMaxLength ))
    {
        CPLFree( pszText );
        return NULL;
    }
    else
        return pszText;
}

/************************************************************************/
/*                       OGR_G_ExportToKMLTree()                        */
/************************************************************************/

CPLXMLNode *OGR_G_ExportToKMLTree( OGRGeometryH hGeometry )
{
    char        *pszText;
    CPLXMLNode  *psTree;

    pszText = OGR_G_ExportToKML( hGeometry );
    if( pszText == NULL )
        return NULL;

    psTree = CPLParseXMLString( pszText );

    CPLFree( pszText );

    return psTree;
}