PK_ERROR_code_t PK_REGION_combine_bodies
(
--- received arguments ---
PK_REGION_t     target_region,         --- a region of the first body
PK_BODY_t       tool_body              --- the second body
)


This function combines two bodies into a single disconnected body.


Specific Errors:
    PK_ERROR_solid_region           target_region is not void
    PK_ERROR_same_tool_and_target   target_region belongs to tool_body


The infinite region of the tool body is deleted and its contents
transferred into the target region (which must belong to a different
body, and must be void); the tool body is then deleted.

This is a purely topological operation; it does not check that the two
bodies do not clash, or that the tool body is wholly contained within
the target region.

If the body types of the given tool and target are the same then the resulting
target body will be of that same type.  If the body types of the tool and
target are different then the resulting target body will be of type
PK_BODY_type_general_c.