As a post process of creating mould geometry is producing the tooling that creates it. This process normally follows a similar route of deciding were parting line should be for the tooling split as well as any core placements required.
I have assisted tooling that has been produced for blow and injection mouldings on plastic bottles and caps. These are normally complex and require water cooling to allow thermal expansion to be controlled.
Another area is friction tooling, this project below was create to allow two plastic components to be welded together using friction. The process requires surfaces to be created which are referenced to the original geometry. These are then developed into tooling sets for top and bottom.
I had also created resin tools for foam mouldings, these are more normally more relaxed regarding draft angles due to the softness of the foam when ejected from the mould tooling.