5.13.3. Target Part IDs and Source Part IDs

NumTargetPIDs = INT	Defines the number of parts in the target mesh which are considered within the mapping. This option must be followed by TargetPID#i definitions.
TargetPID#i = INT	Defines as many part IDs as given in NumTargetPIDs. These parts are considered for the mapping.
NumSourcePIDs = INT	Defines the number of parts in the source mesh which are considered within the mapping. This option must be followed by SourcePID#i definitions.
SourcePID#i = INT	Defines as many part IDs as given in NumSourcePIDs. These parts are considered for the mapping.

Note: The options above specifically narrow down the scope of the mapping procedure to defined-part IDs. Other parts are ignored on both source and target meshes.