Le vendredi 02 mars 2012 18:26:52, huahu a écrit :
> Hi,
> I try to edit in this way, but it can not work,although it can save
> geometry,but it cannot save feature.
The DXF driver doesn't support update of existing files. It supports reading a
file or writing a new one. So you'll have to iterate over the source file
features and write them in a new DXF file.
> My purpose is alter the previous file,and copy a DataSource to create a
> new file.
>
>
> OGRRegisterAll();
> OGRDataSource *poDS = OGRSFDriverRegistrar::Open( srcname.c_str(), FALSE );
> int layercount=poDS->GetLayerCount();
>
> for(int num=0;num<layercount;num++)
> {
> OGRLayer* poLayer = poDS->GetLayer(num);
> OGRFeature * pFeature;
> poLayer->ResetReading();
>
> while ((pFeature=poLayer->GetNextFeature())!=NULL)
> {
> OGRGeometry* pGeometry = pFeature->GetGeometryRef();
> OGRwkbGeometryType geoType = pGeometry->getGeometryType();
> if (pGeometry != NULL &&wkbPoint==geoType)
> {
> //change the coordinate value
> OGRPoint *poPoint = (OGRPoint *) pGeometry;
> double pointx=poPoint->getX()-X;
> double pointy=poPoint->getY()-Y;
> poPoint->setX((pointx*cos(e)-pointy*sin(e))+X);
> poPoint->setY((pointx*sin(e)+pointy*cos(e))+Y);
> }
> else if(pGeometry != NULL &&wkbLineString==geoType)
> {
> OGRLineString* pLineGeo = (OGRLineString*)pGeometry;
> int linestringsize=pLineGeo->getNumPoints();
> for(int i=0;i<linestringsize;i++)
> {
> double
> pointx=((pLineGeo->getX(i)-X)*cos(e*PI/180.0)-(pLineGeo->getY(i)-Y)*sin(e*P
> I/180.0))+X; double
> pointy=((pLineGeo->getX(i)-X)*sin(e*PI/180.0)+(pLineGeo->getY(i)-Y)*cos(e*P
> I/180.0))+Y; pLineGeo->setPoint(i,pointx,pointy);
> }
> }
> else if( pGeometry != NULL &&wkbPolygon==geoType)
> {
> OGRPolygon *pPolygon=(OGRPolygon*)pGeometry;
> OGRLinearRing *ogrlring=pPolygon->getExteriorRing();
> int lenth=ogrlring->getNumPoints();
> for(int i=0;i<lenth;i++)
> {
> double
> pointx=((ogrlring->getX(i)-X)*cos(e*PI/180.0)-(ogrlring->getY(i)-Y)*sin(e*P
> I/180.0))+X; double
> pointy=((ogrlring->getX(i)-X)*sin(e*PI/180.0)+(ogrlring->getY(i)-Y)*cos(e*P
> I/180.0))+Y; ogrlring->setPoint(i,pointx,pointy);
> }
> }
> else
> {
> }
> poLayer->SetFeature(pFeature); //it can not save feature
>
> }
> }
> OGRSFDriver* poDriver =
> OGRSFDriverRegistrar::GetRegistrar()->GetDriverByName("ESRI Shapefile");
> OGRDataSource* desDS = poDriver->CopyDataSource(poDS,desname.c_str(),0);
> OGRDataSource::DestroyDataSource( desDS );
> OGRDataSource::DestroyDataSource( poDS );
> OGRCleanupAll();
>
>
> Can you help me?
>
> Thank you!
>
> Cheers,
> Huahu
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