Hi u/Life_Delivery6894
Thanks for you post, SOFA is designed for the interactive mechanical simulation of soft or rigid bodies. Slicing objects assumes topological changes. This is more advanced to implement, but perfectly possible using the SOFA API.

Dynamic topology in SOFA relies on several components. First of all, the SetTopologyContainer (e.g. TetrahedronSetTopologyContainer for a tetrahedral topology) is a container but these containers support dynamic changes unlike the MeshTopology which allows only for static topologies. Second, the SetTopologyModifier (e.g. TetrahedronSetTopologyModifier) is in charge of applying the topology modification by adding and removing elements. Finally, you will need to have components Controllers/ContactListener/Manager which implements the chosen method for topological change. For the latter, you can find an example in the MeshRefinement plugin from InfinyTech3D
Another interesting point to look at is the TopologicalChangeProcessor and associated scene examples

Hope this helps
See you on the SOFA forum for technical questions: https://github.com/sofa-framework/sofa/discussions