now it can work on a variety of cases.
Known bug: due to current design of primitive, some primitives with sharp rounding may not be detected, so that their integrand may not be correct, as well as their output mesh.
TODO: fetch ia_data and ia_indices from .msgpack, and statically write them into inline data files. Then making ia_data and ia_indices fully compile-time variables into the library.
Zhicheng Wang