People who, unlike me, actually know something about programming often talk about design patterns. One common idea is to compose objects out of other objects.
I was able to add four new APT-tool like cutter classes to ocl with about 5-lines of code for each cutter (sans the bugfixing, taking much longer, that also took place simultaneously 🙂 ).
These show CL-points resulting from the vertexDrop() function, which results in a shape that looks like the cutter, but inverted.
Other combinations of the basic shapes (cylinder, sphere, torus, cone) are fairly easy to add now also if someone actually needs them.