Hi Luke,
If I understand correctly, you have different objects/bones in the same triangle mesh and you want to separate some of them?
You can use the TriangleMesh3D.operations for something like that:
val mesh: TriangleMesh[_3D] = ???
val pointFilter: Point[_3D] => Boolean = ???
val reducedMesh = mesh.operations.maskSpatially(pointFilter).transformedMesh
Can you express a function given the mentioned landmarks which decide for every point if it should be retained or not? Otherwise, it would be good if you could describe a bit more your landmarks, shapes, and how you intend to use them.