C++ OGRGeometry::getEnvelope方法代码示例

OGRErr OGRLayer::GetExtent(OGREnvelope *psExtent, int bForce )

{
    OGRFeature  *poFeature;
    OGREnvelope oEnv;
    GBool       bExtentSet = FALSE;

    /* -------------------------------------------------------------------- */
    /*      If this layer has a none geometry type, then we can             */
    /*      reasonably assume there are not extents available.              */
    /* -------------------------------------------------------------------- */
    if( GetLayerDefn()->GetGeomType() == wkbNone )
    {
        psExtent->MinX = 0.0;
        psExtent->MaxX = 0.0;
        psExtent->MinY = 0.0;
        psExtent->MaxY = 0.0;

        return OGRERR_FAILURE;
    }

    /* -------------------------------------------------------------------- */
    /*      If not forced, we should avoid having to scan all the           */
    /*      features and just return a failure.                             */
    /* -------------------------------------------------------------------- */
    if( !bForce )
        return OGRERR_FAILURE;

    /* -------------------------------------------------------------------- */
    /*      OK, we hate to do this, but go ahead and read through all       */
    /*      the features to collect geometries and build extents.           */
    /* -------------------------------------------------------------------- */
    ResetReading();
    while( (poFeature = GetNextFeature()) != NULL )
    {
        OGRGeometry *poGeom = poFeature->GetGeometryRef();
        if (poGeom && !bExtentSet)
        {
            poGeom->getEnvelope(psExtent);
            bExtentSet = TRUE;
        }
        else if (poGeom)
        {
            poGeom->getEnvelope(&oEnv);
            if (oEnv.MinX < psExtent->MinX)
                psExtent->MinX = oEnv.MinX;
            if (oEnv.MinY < psExtent->MinY)
                psExtent->MinY = oEnv.MinY;
            if (oEnv.MaxX > psExtent->MaxX)
                psExtent->MaxX = oEnv.MaxX;
            if (oEnv.MaxY > psExtent->MaxY)
                psExtent->MaxY = oEnv.MaxY;
        }
        delete poFeature;
    }
    ResetReading();

    return (bExtentSet ? OGRERR_NONE : OGRERR_FAILURE);
}

OGRErr OGRGeoJSONSeqWriteLayer::ICreateFeature( OGRFeature* poFeature )
{
    VSILFILE* fp = m_poDS->GetOutputFile();

    std::unique_ptr<OGRFeature> poFeatureToWrite;
    if( m_poCT != nullptr )
    {
        poFeatureToWrite.reset(new OGRFeature(m_poFeatureDefn));
        poFeatureToWrite->SetFrom( poFeature );
        poFeatureToWrite->SetFID( poFeature->GetFID() );
        OGRGeometry* poGeometry = poFeatureToWrite->GetGeometryRef();
        if( poGeometry )
        {
            const char* const apszOptions[] = { "WRAPDATELINE=YES", nullptr };
            OGRGeometry* poNewGeom =
                OGRGeometryFactory::transformWithOptions(
                    poGeometry, m_poCT, const_cast<char**>(apszOptions));
            if( poNewGeom == nullptr )
            {
                return OGRERR_FAILURE;
            }

            OGREnvelope sEnvelope;
            poNewGeom->getEnvelope(&sEnvelope);
            if( sEnvelope.MinX < -180.0 || sEnvelope.MaxX > 180.0 ||
                sEnvelope.MinY < -90.0 || sEnvelope.MaxY > 90.0 )
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Geometry extent outside of [-180.0,180.0]x[-90.0,90.0] bounds");
                return OGRERR_FAILURE;
            }

            poFeatureToWrite->SetGeometryDirectly( poNewGeom );
        }
    }

    json_object* poObj =
        OGRGeoJSONWriteFeature(
            poFeatureToWrite.get() ? poFeatureToWrite.get() : poFeature,
            m_oWriteOptions );
    CPLAssert( nullptr != poObj );

    if( m_bRS )
    {
        VSIFPrintfL( fp, "%c", RS);
    }
    VSIFPrintfL( fp, "%s\n", json_object_to_json_string( poObj ) );

    json_object_put( poObj );

    return OGRERR_NONE;
}

OGRErr OGRLayer::GetExtent(OGREnvelope *psExtent, int bForce )

{
    OGRFeature  *poFeature;
    OGREnvelope oEnv;
    GBool       bExtentSet = FALSE;

    if( !bForce )
        return OGRERR_FAILURE;

    ResetReading();
    while( (poFeature = GetNextFeature()) != NULL )
    {
        OGRGeometry *poGeom = poFeature->GetGeometryRef();
        if (poGeom && !bExtentSet)
        {
            poGeom->getEnvelope(psExtent);
            bExtentSet = TRUE;
        }
        else if (poGeom)
        {
            poGeom->getEnvelope(&oEnv);
            if (oEnv.MinX < psExtent->MinX)
                psExtent->MinX = oEnv.MinX;
            if (oEnv.MinY < psExtent->MinY)
                psExtent->MinY = oEnv.MinY;
            if (oEnv.MaxX > psExtent->MaxX)
                psExtent->MaxX = oEnv.MaxX;
            if (oEnv.MaxY > psExtent->MaxY)
                psExtent->MaxY = oEnv.MaxY;
        }
        delete poFeature;
    }
    ResetReading();

    return (bExtentSet ? OGRERR_NONE : OGRERR_FAILURE);
}

void GetFeatureBoundsFunc(const void* hFeature, CPLRectObj* pBounds)
{
    OGRFeature* pFeature = (OGRFeature*)hFeature;
    if(!pFeature)
        return;
    OGRGeometry* pGeom = pFeature->GetGeometryRef();
    if(!pGeom)
        return;
    OGREnvelope Env;
    pGeom->getEnvelope(&Env);
    pBounds->minx = Env.MinX;
    pBounds->maxx = Env.MaxX;
    pBounds->miny = Env.MinY;
    pBounds->maxy = Env.MaxY;
}

OGRErr OGRGeoJSONWriteLayer::ICreateFeature( OGRFeature* poFeature )
{
    VSILFILE* fp = poDS_->GetOutputFile();

    if( NULL == poFeature )
    {
        CPLDebug( "GeoJSON", "Feature is null" );
        return OGRERR_INVALID_HANDLE;
    }

    json_object* poObj = OGRGeoJSONWriteFeature( poFeature, bWriteBBOX, nCoordPrecision );
    CPLAssert( NULL != poObj );

    if( nOutCounter_ > 0 )
    {
        /* Separate "Feature" entries in "FeatureCollection" object. */
        VSIFPrintfL( fp, ",\n" );
    }
    VSIFPrintfL( fp, "%s", json_object_to_json_string( poObj ) );

    json_object_put( poObj );

    ++nOutCounter_;

    OGRGeometry* poGeometry = poFeature->GetGeometryRef();
    if ( bWriteBBOX && !poGeometry->IsEmpty() )
    {
        OGREnvelope3D sEnvelope;
        poGeometry->getEnvelope(&sEnvelope);

        if( poGeometry->getCoordinateDimension() == 3 )
            bBBOX3D = TRUE;

        sEnvelopeLayer.Merge(sEnvelope);
    }

    return OGRERR_NONE;
}

OGRErr OGRGeoJSONWriteLayer::ICreateFeature( OGRFeature* poFeature )
{
    VSILFILE* fp = poDS_->GetOutputFile();

    OGRFeature* poFeatureToWrite;
    if( poCT_ != nullptr || bRFC7946_ )
    {
        poFeatureToWrite = new OGRFeature(poFeatureDefn_);
        poFeatureToWrite->SetFrom( poFeature );
        poFeatureToWrite->SetFID( poFeature->GetFID() );
        OGRGeometry* poGeometry = poFeatureToWrite->GetGeometryRef();
        if( poGeometry )
        {
            const char* const apszOptions[] = { "WRAPDATELINE=YES", nullptr };
            OGRGeometry* poNewGeom =
                OGRGeometryFactory::transformWithOptions(
                    poGeometry, poCT_, const_cast<char**>(apszOptions),
                    oTransformCache_);
            if( poNewGeom == nullptr )
            {
                delete poFeatureToWrite;
                return OGRERR_FAILURE;
            }

            OGREnvelope sEnvelope;
            poNewGeom->getEnvelope(&sEnvelope);
            if( sEnvelope.MinX < -180.0 || sEnvelope.MaxX > 180.0 ||
                sEnvelope.MinY < -90.0 || sEnvelope.MaxY > 90.0 )
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Geometry extent outside of [-180.0,180.0]x[-90.0,90.0] bounds");
                delete poFeatureToWrite;
                return OGRERR_FAILURE;
            }

            poFeatureToWrite->SetGeometryDirectly( poNewGeom );
        }
    }
    else
    {
        poFeatureToWrite = poFeature;
    }

    json_object* poObj =
        OGRGeoJSONWriteFeature( poFeatureToWrite, oWriteOptions_ );
    CPLAssert( nullptr != poObj );

    if( nOutCounter_ > 0 )
    {
        /* Separate "Feature" entries in "FeatureCollection" object. */
        VSIFPrintfL( fp, ",\n" );
    }
    VSIFPrintfL( fp, "%s", json_object_to_json_string( poObj ) );

    json_object_put( poObj );

    ++nOutCounter_;

    OGRGeometry* poGeometry = poFeatureToWrite->GetGeometryRef();
    if( bWriteFC_BBOX && poGeometry != nullptr && !poGeometry->IsEmpty() )
    {
        OGREnvelope3D sEnvelope = OGRGeoJSONGetBBox( poGeometry,
                                                     oWriteOptions_ );
        if( poGeometry->getCoordinateDimension() == 3 )
            bBBOX3D = true;

        if( !sEnvelopeLayer.IsInit() )
        {
            sEnvelopeLayer = sEnvelope;
        }
        else if( oWriteOptions_.bBBOXRFC7946 )
        {
            const bool bEnvelopeCrossAM = ( sEnvelope.MinX > sEnvelope.MaxX );
            const bool bEnvelopeLayerCrossAM =
                                ( sEnvelopeLayer.MinX > sEnvelopeLayer.MaxX );
            if( bEnvelopeCrossAM )
            {
                if( bEnvelopeLayerCrossAM )
                {
                    sEnvelopeLayer.MinX = std::min(sEnvelopeLayer.MinX,
                                                   sEnvelope.MinX);
                    sEnvelopeLayer.MaxX = std::max(sEnvelopeLayer.MaxX,
                                                   sEnvelope.MaxX);
                }
                else
                {
                    if( sEnvelopeLayer.MinX > 0 )
                    {
                        sEnvelopeLayer.MinX = std::min(sEnvelopeLayer.MinX,
                                                       sEnvelope.MinX);
                        sEnvelopeLayer.MaxX = sEnvelope.MaxX;
                    }
                    else if( sEnvelopeLayer.MaxX < 0 )
                    {
                        sEnvelopeLayer.MaxX = std::max(sEnvelopeLayer.MaxX,
                                                       sEnvelope.MaxX);
                        sEnvelopeLayer.MinX = sEnvelope.MinX;
                    }
                    else
                    {
//.........这里部分代码省略.........

//.........这里部分代码省略.........
                        wkbHasZ( poLayer->GetGeomType() ) ? "XYZ" : "XY",
                        nSRSId, static_cast<int>(bCreateSpatialIndex) );
        }
    }
#endif // HAVE_SPATIALITE
    char* pszErrMsg = NULL;
    int rc = sqlite3_exec( hDB, osSQL.c_str(), NULL, NULL, &pszErrMsg );
    if( pszErrMsg != NULL )
    {
        CPLDebug("SQLITE", "%s -> %s", osSQL.c_str(), pszErrMsg);
        sqlite3_free(pszErrMsg);
    }

#ifdef HAVE_SPATIALITE
/* -------------------------------------------------------------------- */
/*      Should we create a spatial index ?.                             */
/* -------------------------------------------------------------------- */
    if( !bSpatialiteDB || !bCreateSpatialIndex )
        return rc == SQLITE_OK;

    CPLDebug("SQLITE", "Create spatial index %s", osIdxNameRaw.c_str());

    /* ENABLE_VIRTUAL_OGR_SPATIAL_INDEX is not defined */
#ifdef ENABLE_VIRTUAL_OGR_SPATIAL_INDEX
    osSQL.Printf("CREATE VIRTUAL TABLE \"%s\" USING "
                    "VirtualOGRSpatialIndex(%d, '%s', pkid, xmin, xmax, ymin, ymax)",
                    osIdxNameEscaped.c_str(),
                    nExtraDS,
                    OGRSQLiteEscape(oLayerDesc.osLayerName).c_str());

    rc = sqlite3_exec( hDB, osSQL.c_str(), NULL, NULL, NULL );
    if( rc != SQLITE_OK )
    {
        CPLDebug( "SQLITE",
                  "Error occurred during spatial index creation : %s",
                  sqlite3_errmsg(hDB));
    }
#else //  ENABLE_VIRTUAL_OGR_SPATIAL_INDEX
    rc = sqlite3_exec( hDB, "BEGIN", NULL, NULL, NULL );

    osSQL.Printf("CREATE VIRTUAL TABLE \"%s\" "
                    "USING rtree(pkid, xmin, xmax, ymin, ymax)",
                    osIdxNameEscaped.c_str());

    if( rc == SQLITE_OK )
        rc = sqlite3_exec( hDB, osSQL.c_str(), NULL, NULL, NULL );

    sqlite3_stmt *hStmt = NULL;
    if( rc == SQLITE_OK )
    {
        const char* pszInsertInto = CPLSPrintf(
            "INSERT INTO \"%s\" (pkid, xmin, xmax, ymin, ymax) "
            "VALUES (?,?,?,?,?)", osIdxNameEscaped.c_str());
        rc = sqlite3_prepare(hDB, pszInsertInto, -1, &hStmt, NULL);
    }

    OGRFeature* poFeature;
    OGREnvelope sEnvelope;
    OGR2SQLITE_IgnoreAllFieldsExceptGeometry(poLayer);
    poLayer->ResetReading();

    while( rc == SQLITE_OK &&
            (poFeature = poLayer->GetNextFeature()) != NULL )
    {
        OGRGeometry* poGeom = poFeature->GetGeometryRef();
        if( poGeom != NULL && !poGeom->IsEmpty() )
        {
            poGeom->getEnvelope(&sEnvelope);
            sqlite3_bind_int64(hStmt, 1,
                                (sqlite3_int64) poFeature->GetFID() );
            sqlite3_bind_double(hStmt, 2, sEnvelope.MinX);
            sqlite3_bind_double(hStmt, 3, sEnvelope.MaxX);
            sqlite3_bind_double(hStmt, 4, sEnvelope.MinY);
            sqlite3_bind_double(hStmt, 5, sEnvelope.MaxY);
            rc = sqlite3_step(hStmt);
            if( rc == SQLITE_OK || rc == SQLITE_DONE )
                rc = sqlite3_reset(hStmt);
        }
        delete poFeature;
    }

    poLayer->SetIgnoredFields(NULL);

    sqlite3_finalize(hStmt);

    if( rc == SQLITE_OK )
        rc = sqlite3_exec( hDB, "COMMIT", NULL, NULL, NULL );
    else
    {
        CPLDebug( "SQLITE",
                  "Error occurred during spatial index creation : %s",
                  sqlite3_errmsg(hDB));
        rc = sqlite3_exec( hDB, "ROLLBACK", NULL, NULL, NULL );
    }
#endif //  ENABLE_VIRTUAL_OGR_SPATIAL_INDEX

#endif // HAVE_SPATIALITE

    return rc == SQLITE_OK;
}

OGRErr OGRDXFWriterLayer::ICreateFeature( OGRFeature *poFeature )

{
    OGRGeometry *poGeom = poFeature->GetGeometryRef();
    OGRwkbGeometryType eGType = wkbNone;

    if( poGeom != nullptr )
    {
        if( !poGeom->IsEmpty() )
        {
            OGREnvelope sEnvelope;
            poGeom->getEnvelope(&sEnvelope);
            poDS->UpdateExtent(&sEnvelope);
        }
        eGType = wkbFlatten(poGeom->getGeometryType());
    }

    if( eGType == wkbPoint )
    {
        const char *pszBlockName = poFeature->GetFieldAsString("BlockName");

        // We don't want to treat as a blocks ref if the block is not defined
        if( pszBlockName
            && poDS->oHeaderDS.LookupBlock(pszBlockName) == nullptr )
        {
            if( poDS->poBlocksLayer == nullptr
                || poDS->poBlocksLayer->FindBlock(pszBlockName) == nullptr )
                pszBlockName = nullptr;
        }

        if( pszBlockName != nullptr )
            return WriteINSERT( poFeature );

        else if( poFeature->GetStyleString() != nullptr
            && STARTS_WITH_CI(poFeature->GetStyleString(), "LABEL") )
            return WriteTEXT( poFeature );
        else
            return WritePOINT( poFeature );
    }
    else if( eGType == wkbLineString
             || eGType == wkbMultiLineString )
        return WritePOLYLINE( poFeature );

    else if( eGType == wkbPolygon
             || eGType == wkbTriangle
             || eGType == wkbMultiPolygon)
    {
        if( bWriteHatch )
            return WriteHATCH( poFeature );
        else
            return WritePOLYLINE( poFeature );
    }

    // Explode geometry collections into multiple entities.
    else if( eGType == wkbGeometryCollection )
    {
        OGRGeometryCollection *poGC =
            poFeature->StealGeometry()->toGeometryCollection();
        for( auto&& poMember: poGC )
        {
            poFeature->SetGeometry( poMember );

            OGRErr eErr = CreateFeature( poFeature );

            if( eErr != OGRERR_NONE )
            {
                delete poGC;
                return eErr;
            }
        }

        poFeature->SetGeometryDirectly( poGC );
        return OGRERR_NONE;
    }
    else
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "No known way to write feature with geometry '%s'.",
                  OGRGeometryTypeToName(eGType) );
        return OGRERR_FAILURE;
    }
}

OGRErr OGRIngresTableLayer::GetExtent(OGREnvelope *psExtent, int bForce )

{
	if( GetLayerDefn()->GetGeomType() == wkbNone )
    {
        psExtent->MinX = 0.0;
        psExtent->MaxX = 0.0;
        psExtent->MinY = 0.0;
        psExtent->MaxY = 0.0;
        
        return OGRERR_FAILURE;
    }

	OGREnvelope oEnv;
	CPLString   osCommand;
	GBool       bExtentSet = FALSE;

	osCommand.Printf( "SELECT Envelope(%s) FROM %s;", pszGeomColumn, pszGeomColumnTable);

	if (ingres_query(poDS->GetConn(), osCommand) == 0)
	{
		INGRES_RES* result = ingres_use_result(poDS->GetConn());
		if ( result == NULL )
        {
            poDS->ReportError( "ingres_use_result() failed on extents query." );
            return OGRERR_FAILURE;
        }

		INGRES_ROW row; 
		unsigned long *panLengths = NULL;
		while ((row = ingres_fetch_row(result)))
		{
			if (panLengths == NULL)
			{
				panLengths = ingres_fetch_lengths( result );
				if ( panLengths == NULL )
				{
					poDS->ReportError( "ingres_fetch_lengths() failed on extents query." );
					return OGRERR_FAILURE;
				}
			}

			OGRGeometry *poGeometry = NULL;
			// Geometry columns will have the first 4 bytes contain the SRID.
			OGRGeometryFactory::createFromWkb(((GByte *)row[0]) + 4, 
											  NULL,
											  &poGeometry,
											  panLengths[0] - 4 );

			if ( poGeometry != NULL )
			{
				if (poGeometry && !bExtentSet)
				{
					poGeometry->getEnvelope(psExtent);
					bExtentSet = TRUE;
				}
				else if (poGeometry)
				{
					poGeometry->getEnvelope(&oEnv);
					if (oEnv.MinX < psExtent->MinX) 
						psExtent->MinX = oEnv.MinX;
					if (oEnv.MinY < psExtent->MinY) 
						psExtent->MinY = oEnv.MinY;
					if (oEnv.MaxX > psExtent->MaxX) 
						psExtent->MaxX = oEnv.MaxX;
					if (oEnv.MaxY > psExtent->MaxY) 
						psExtent->MaxY = oEnv.MaxY;
				}
				delete poGeometry;
			}
		}

		ingres_free_result(result);      
	}

	return (bExtentSet ? OGRERR_NONE : OGRERR_FAILURE);
}

int NASReader::PrescanForSchema( int bGetExtents )

{
    GMLFeature  *poFeature;

    if( m_pszFilename == NULL )
        return FALSE;

    SetClassListLocked( FALSE );

    ClearClasses();
    if( !SetupParser() )
        return FALSE;

    std::string osWork;

    while( (poFeature = NextFeature()) != NULL )
    {
        GMLFeatureClass *poClass = poFeature->GetClass();

        if( poClass->GetFeatureCount() == -1 )
            poClass->SetFeatureCount( 1 );
        else
            poClass->SetFeatureCount( poClass->GetFeatureCount() + 1 );

#ifdef SUPPORT_GEOMETRY
        if( bGetExtents )
        {
            OGRGeometry *poGeometry = NULL;

            const CPLXMLNode* const * papsGeometry = poFeature->GetGeometryList();
            if( papsGeometry[0] != NULL )
            {
                poGeometry = (OGRGeometry*) OGR_G_CreateFromGMLTree(papsGeometry[0]);
            }

            if( poGeometry != NULL )
            {
                double  dfXMin, dfXMax, dfYMin, dfYMax;
                OGREnvelope sEnvelope;
                OGRwkbGeometryType eGType = (OGRwkbGeometryType) 
                    poClass->GetGeometryType();

                // Merge SRSName into layer.
                const char* pszSRSName = GML_ExtractSrsNameFromGeometry(papsGeometry, osWork, FALSE);
//                if (pszSRSName != NULL)
//                    m_bCanUseGlobalSRSName = FALSE;
                poClass->MergeSRSName(pszSRSName);

                // Merge geometry type into layer.
                if( poClass->GetFeatureCount() == 1 && eGType == wkbUnknown )
                    eGType = wkbNone;

                poClass->SetGeometryType( 
                    (int) OGRMergeGeometryTypes(
                        eGType, poGeometry->getGeometryType() ) );

                // merge extents.
                poGeometry->getEnvelope( &sEnvelope );
                delete poGeometry;
                if( poClass->GetExtents(&dfXMin, &dfXMax, &dfYMin, &dfYMax) )
                {
                    dfXMin = MIN(dfXMin,sEnvelope.MinX);
                    dfXMax = MAX(dfXMax,sEnvelope.MaxX);
                    dfYMin = MIN(dfYMin,sEnvelope.MinY);
                    dfYMax = MAX(dfYMax,sEnvelope.MaxY);
                }
                else
                {
                    dfXMin = sEnvelope.MinX;
                    dfXMax = sEnvelope.MaxX;
                    dfYMin = sEnvelope.MinY;
                    dfYMax = sEnvelope.MaxY;
                }

                poClass->SetExtents( dfXMin, dfXMax, dfYMin, dfYMax );
            }
            else 
            {
                if( poClass->GetGeometryType() == (int) wkbUnknown 
                    && poClass->GetFeatureCount() == 1 )
                    poClass->SetGeometryType( wkbNone );
            }
#endif /* def SUPPORT_GEOMETRY */
        }
        
        delete poFeature;
    }

    CleanupParser();

    return GetClassCount() > 0;
}

//.........这里部分代码省略.........
                             poFeatureDefn->GetName(),
                             poFeature->GetFID() );
        }
        else if (nGMLIdIndex >= 0 && poFeature->IsFieldSet( nGMLIdIndex ) )
        {
            poDS->PrintLine( fp, "%s fid=\"%s\">",
                             poFeatureDefn->GetName(),
                             poFeature->GetFieldAsString(nGMLIdIndex) );
        }
        else
        {
            poDS->PrintLine( fp, "%s fid=\"%s." CPL_FRMT_GIB "\">",
                             poFeatureDefn->GetName(),
                             poFeatureDefn->GetName(),
                             poFeature->GetFID() );
        }
    }


    for( int iGeomField = 0; iGeomField < poFeatureDefn->GetGeomFieldCount(); iGeomField++ )
    {
        OGRGeomFieldDefn *poFieldDefn = poFeatureDefn->GetGeomFieldDefn(iGeomField);

        // Write out Geometry - for now it isn't indented properly.
        /* GML geometries don't like very much the concept of empty geometry */
        OGRGeometry* poGeom = poFeature->GetGeomFieldRef(iGeomField);
        if( poGeom != NULL && !poGeom->IsEmpty())
        {
            char    *pszGeometry;
            OGREnvelope3D sGeomBounds;

            int nCoordDimension = poGeom->getCoordinateDimension();

            poGeom->getEnvelope( &sGeomBounds );
            if( bSameSRS )
                poDS->GrowExtents( &sGeomBounds, nCoordDimension );

            if (poGeom->getSpatialReference() == NULL && poFieldDefn->GetSpatialRef() != NULL)
                poGeom->assignSpatialReference(poFieldDefn->GetSpatialRef());

            if (bIsGML3Output && poDS->WriteFeatureBoundedBy())
            {
                bool bCoordSwap;

                char* pszSRSName = GML_GetSRSName(poGeom->getSpatialReference(), poDS->IsLongSRSRequired(), &bCoordSwap);
                char szLowerCorner[75], szUpperCorner[75];
                if (bCoordSwap)
                {
                    OGRMakeWktCoordinate(szLowerCorner, sGeomBounds.MinY, sGeomBounds.MinX, sGeomBounds.MinZ, nCoordDimension);
                    OGRMakeWktCoordinate(szUpperCorner, sGeomBounds.MaxY, sGeomBounds.MaxX, sGeomBounds.MaxZ, nCoordDimension);
                }
                else
                {
                    OGRMakeWktCoordinate(szLowerCorner, sGeomBounds.MinX, sGeomBounds.MinY, sGeomBounds.MinZ, nCoordDimension);
                    OGRMakeWktCoordinate(szUpperCorner, sGeomBounds.MaxX, sGeomBounds.MaxY, sGeomBounds.MaxZ, nCoordDimension);
                }
                if (bWriteSpaceIndentation)
                    VSIFPrintfL(fp, "      ");
                poDS->PrintLine( fp, "<gml:boundedBy><gml:Envelope%s%s><gml:lowerCorner>%s</gml:lowerCorner><gml:upperCorner>%s</gml:upperCorner></gml:Envelope></gml:boundedBy>",
                                (nCoordDimension == 3) ? " srsDimension=\"3\"" : "",pszSRSName, szLowerCorner, szUpperCorner);
                CPLFree(pszSRSName);
            }

            char** papszOptions = (bIsGML3Output) ? CSLAddString(NULL, "FORMAT=GML3") : NULL;
            if (bIsGML3Output && !poDS->IsLongSRSRequired())
                papszOptions = CSLAddString(papszOptions, "GML3_LONGSRS=NO");

OGRErr OGRDXFWriterLayer::ICreateFeature( OGRFeature *poFeature )

{
    OGRGeometry *poGeom = poFeature->GetGeometryRef();
    OGRwkbGeometryType eGType = wkbNone;
    
    if( poGeom != NULL )
    {
        if( !poGeom->IsEmpty() )
        {
            OGREnvelope sEnvelope;
            poGeom->getEnvelope(&sEnvelope);
            poDS->UpdateExtent(&sEnvelope);
        }
        eGType = wkbFlatten(poGeom->getGeometryType());
    }

    if( eGType == wkbPoint )
    {
        const char *pszBlockName = poFeature->GetFieldAsString("BlockName");

        // we don't want to treat as a block ref if we are writing blocks layer
        if( pszBlockName != NULL
            && poDS->poBlocksLayer != NULL 
            && poFeature->GetDefnRef() == poDS->poBlocksLayer->GetLayerDefn())
            pszBlockName = NULL;

        // We don't want to treat as a blocks ref if the block is not defined
        if( pszBlockName 
            && poDS->oHeaderDS.LookupBlock(pszBlockName) == NULL )
        {
            if( poDS->poBlocksLayer == NULL
                || poDS->poBlocksLayer->FindBlock(pszBlockName) == NULL )
                pszBlockName = NULL;
        }
                                  
        if( pszBlockName != NULL )
            return WriteINSERT( poFeature );
            
        else if( poFeature->GetStyleString() != NULL
            && EQUALN(poFeature->GetStyleString(),"LABEL",5) )
            return WriteTEXT( poFeature );
        else
            return WritePOINT( poFeature );
    }
    else if( eGType == wkbLineString 
             || eGType == wkbMultiLineString )
        return WritePOLYLINE( poFeature );

    else if( eGType == wkbPolygon 
             || eGType == wkbMultiPolygon )
    {
        if( bWriteHatch )
            return WriteHATCH( poFeature );
        else
            return WritePOLYLINE( poFeature );
    }

    // Explode geometry collections into multiple entities.
    else if( eGType == wkbGeometryCollection )
    {
        OGRGeometryCollection *poGC = (OGRGeometryCollection *)
            poFeature->StealGeometry();
        int iGeom;

        for( iGeom = 0; iGeom < poGC->getNumGeometries(); iGeom++ )
        {
            poFeature->SetGeometry( poGC->getGeometryRef(iGeom) );
                                    
            OGRErr eErr = CreateFeature( poFeature );
            
            if( eErr != OGRERR_NONE )
                return eErr;

        }
        
        poFeature->SetGeometryDirectly( poGC );
        return OGRERR_NONE;
    }
    else 
    {
        CPLError( CE_Failure, CPLE_AppDefined,
                  "No known way to write feature with geometry '%s'.",
                  OGRGeometryTypeToName(eGType) );
        return OGRERR_FAILURE;
    }
}

//.........这里部分代码省略.........
                     "Error occured during spatial index creation : %s",
                     sqlite3_errmsg(hDB));
        }
#else //  ENABLE_VIRTUAL_OGR_SPATIAL_INDEX
        rc = sqlite3_exec( hDB, "BEGIN", NULL, NULL, NULL );

        osSQL.Printf("CREATE VIRTUAL TABLE \"%s\" "
                     "USING rtree(pkid, xmin, xmax, ymin, ymax)",
                      osIdxNameEscaped.c_str());

        if( rc == SQLITE_OK )
            rc = sqlite3_exec( hDB, osSQL.c_str(), NULL, NULL, NULL );

        sqlite3_stmt *hStmt = NULL;
        if( rc == SQLITE_OK )
        {
            const char* pszInsertInto = CPLSPrintf(
                "INSERT INTO \"%s\" (pkid, xmin, xmax, ymin, ymax) "
                "VALUES (?,?,?,?,?)", osIdxNameEscaped.c_str());
            rc = sqlite3_prepare(hDB, pszInsertInto, -1, &hStmt, NULL);
        }

        OGRFeature* poFeature;
        OGREnvelope sEnvelope;
        OGR2SQLITE_IgnoreAllFieldsExceptGeometry(poLayer);
        poLayer->ResetReading();

        while( rc == SQLITE_OK &&
               (poFeature = poLayer->GetNextFeature()) != NULL )
        {
            OGRGeometry* poGeom = poFeature->GetGeometryRef();
            if( poGeom != NULL && !poGeom->IsEmpty() )
            {
                poGeom->getEnvelope(&sEnvelope);
                sqlite3_bind_int64(hStmt, 1,
                                   (sqlite3_int64) poFeature->GetFID() );
                sqlite3_bind_double(hStmt, 2, sEnvelope.MinX);
                sqlite3_bind_double(hStmt, 3, sEnvelope.MaxX);
                sqlite3_bind_double(hStmt, 4, sEnvelope.MinY);
                sqlite3_bind_double(hStmt, 5, sEnvelope.MaxY);
                rc = sqlite3_step(hStmt);
                if( rc == SQLITE_OK || rc == SQLITE_DONE )
                    rc = sqlite3_reset(hStmt);
            }
            delete poFeature;
        }

        poLayer->SetIgnoredFields(NULL);

        sqlite3_finalize(hStmt);

        if( rc == SQLITE_OK )
            rc = sqlite3_exec( hDB, "COMMIT", NULL, NULL, NULL );
        else
        {
            CPLDebug("SQLITE",
                     "Error occured during spatial index creation : %s",
                     sqlite3_errmsg(hDB));
            rc = sqlite3_exec( hDB, "ROLLBACK", NULL, NULL, NULL );
        }
#endif //  ENABLE_VIRTUAL_OGR_SPATIAL_INDEX

#endif // HAVE_SPATIALITE

    }

CPLString OGRPLScenesLayer::BuildURL(int nFeatures)
{
    CPLString osURL = osBaseURL + CPLSPrintf("?count=%d", nFeatures);

    if( bAcquiredAscending == 1 )
        osURL += "&order_by=acquired%20asc";
    else if( bAcquiredAscending == 0 )
        osURL += "&order_by=acquired%20desc";
    
    if( m_poFilterGeom != NULL || poMainFilter != NULL )
    {
        OGRGeometry* poIntersection = NULL;
        OGRGeometry* poFilterGeom = m_poFilterGeom;
        if( poFilterGeom ) 
        {
            OGREnvelope sEnvelope;
            poFilterGeom->getEnvelope(&sEnvelope);
            if( sEnvelope.MinX <= -180 && sEnvelope.MinY <= -90 &&
                sEnvelope.MaxX >= 180 && sEnvelope.MaxY >= 90 )
                poFilterGeom = NULL;
        }

        if( poFilterGeom && poMainFilter )
            poIntersection = poFilterGeom->Intersection(poMainFilter);
        else if( poFilterGeom )
            poIntersection = poFilterGeom; 
        else if( poMainFilter )
            poIntersection = poMainFilter;
        if( poIntersection )
        {
            char* pszWKT = NULL;
            OGREnvelope sEnvelope;
            poIntersection->getEnvelope(&sEnvelope);
            if( sEnvelope.MinX == sEnvelope.MaxX && sEnvelope.MinY == sEnvelope.MaxY )
            {
                pszWKT = CPLStrdup(CPLSPrintf("POINT(%.18g %.18g)",
                                            sEnvelope.MinX, sEnvelope.MinY));
            }
            else
                poIntersection->exportToWkt(&pszWKT);

            osURL += "&intersects=";
            char* pszWKTEscaped = CPLEscapeString(pszWKT, -1, CPLES_URL);
            osURL += pszWKTEscaped;
            CPLFree(pszWKTEscaped);
            CPLFree(pszWKT);
        }
        if( poIntersection != m_poFilterGeom && poIntersection != poMainFilter  )
            delete poIntersection;
    }

    if( osFilterURLPart.size() )
    {
        if( osFilterURLPart[0] == '&' )
            osURL += osFilterURLPart;
        else
            osURL = osBaseURL + osFilterURLPart;
    }

    return osURL;
}

int NASReader::PrescanForSchema( int bGetExtents )

{
    GMLFeature  *poFeature;

    if( m_pszFilename == NULL )
        return FALSE;

    SetClassListLocked( FALSE );

    ClearClasses();
    if( !SetupParser() )
        return FALSE;

    while( (poFeature = NextFeature()) != NULL )
    {
        GMLFeatureClass *poClass = poFeature->GetClass();

        if( poClass->GetFeatureCount() == -1 )
            poClass->SetFeatureCount( 1 );
        else
            poClass->SetFeatureCount( poClass->GetFeatureCount() + 1 );

#ifdef SUPPORT_GEOMETRY
        if( bGetExtents )
        {
            OGRGeometry *poGeometry = NULL;

            if( poFeature->GetGeometry() != NULL 
                && strlen(poFeature->GetGeometry()) != 0 )
            {
                poGeometry = (OGRGeometry *) OGR_G_CreateFromGML( 
                    poFeature->GetGeometry() );
            }

            if( poGeometry != NULL )
            {
                double  dfXMin, dfXMax, dfYMin, dfYMax;
                OGREnvelope sEnvelope;
                OGRwkbGeometryType eGType = (OGRwkbGeometryType) 
                    poClass->GetGeometryType();

                // Merge geometry type into layer.
                if( poClass->GetFeatureCount() == 1 && eGType == wkbUnknown )
                    eGType = wkbNone;

                poClass->SetGeometryType( 
                    (int) OGRMergeGeometryTypes(
                        eGType, poGeometry->getGeometryType() ) );

                // merge extents.
                poGeometry->getEnvelope( &sEnvelope );
                delete poGeometry;
                if( poClass->GetExtents(&dfXMin, &dfXMax, &dfYMin, &dfYMax) )
                {
                    dfXMin = MIN(dfXMin,sEnvelope.MinX);
                    dfXMax = MAX(dfXMax,sEnvelope.MaxX);
                    dfYMin = MIN(dfYMin,sEnvelope.MinY);
                    dfYMax = MAX(dfYMax,sEnvelope.MaxY);
                }
                else
                {
                    dfXMin = sEnvelope.MinX;
                    dfXMax = sEnvelope.MaxX;
                    dfYMin = sEnvelope.MinY;
                    dfYMax = sEnvelope.MaxY;
                }

                poClass->SetExtents( dfXMin, dfXMax, dfYMin, dfYMax );
            }
            else 
            {
                if( poClass->GetGeometryType() == (int) wkbUnknown 
                    && poClass->GetFeatureCount() == 1 )
                    poClass->SetGeometryType( wkbNone );
            }
#endif /* def SUPPORT_GEOMETRY */
        }
        
        delete poFeature;
    }

    CleanupParser();

    return GetClassCount() > 0;
}