The `mitkBaseRenderer` listens so several events:
- using `ConnectGeometrySliceEvent` and `ConnectGeometryUpdateEvent` the base renderer reacts on the slice navigation controller
- this results in either `BaseRenderer::SetGeometrySlice` or `BaseRenderer::UpdateGeometry` being called
There seems to be some unnecessary updates inside these two functions so this task should take care of refactoring the different update-functions.
The `mitkBaseRenderer` does not react on the `GeometrySendEvent` of the slice navigation controller.
The corresponding function would be `SetGeometry`, which needs to be inspected as well.