The addon uses several JSON mapping files stored in resources/metahuman/ to define bone-to-bone relationships between the MetaHuman skeleton, the metarig, and the control rig.


Mapping Files Overview

File Purpose Key Fields
metarig_to_source.json Maps metarig bones to source skeleton bones metarig, source
source_to_deform.json Maps source bones to deform bones source, deform
fk_to_source.json Maps FK control bones to source bones source, control
bone_to_vertex.json Maps bone endpoints to mesh vertex indices part, metarig, vertex_index
face_board_bones.json Ordered list of face board bone names (string array)

Template Loading API

All mapping files are loaded through the core/templates.py module:

Function Returns Source File
load_metarig_to_source_mappings(template_name) list[dict[str, str]] metarig_to_source.json
load_source_to_deform_mappings(template_name) list[dict[str, str]] source_to_deform.json
load_fk_to_source_mappings(template_name) list[dict[str, str]] fk_to_source.json
load_bone_to_vertex_mappings(template_name) dict[str, list[dict]] bone_to_vertex.json
load_face_board_bones(template_name) list[str] face_board_bones.json
get_metarig_path(template_name) Path metarig.py
get_template_dir(template_name) Path (directory)

All functions take a template_name parameter (currently always "metahuman") that resolves to a subdirectory under resources/.