RBD setups can be packed into a single geometry using an RBD Pack SOP. The RBD Unpack SOP undoes this operation.
If merges have combined multiple simulations, they will be properly collated and merged in the output.
rbd_type string attribute is used to detect this, so should be preserved.
rbd_name string attribute on the packed primitives will be copied into the contents, allowing one to track where the unpacked geometry came from.