Sometimes ExtractSliceFilter does not update, when it should.

example pseudo code:
"
mitk::ExtractSliceFilter::Pointer extractor = mitk::ExtractSliceFilter::New();
extractor->SetInput(image3D);
extractor->SetWorldGeometry(plane1);
extractor->Update();
mitk::Image::Pointer extractedPlane1 = extractor->GetOutput()->Clone();

extractor->SetWorldGeometry(plane2);
extractor->Update();
mitk::Image::Pointer extractedPlane2 = extractor->GetOutput()->Clone();
"
Even if plane1 and plane2 are different,the resulting images extractedPlane1 and extractedPlane2 are equal. This is because the "SetWorldGeometry" function of the filter is not calling "modified".