Export Face Board Animation

Export face board animations to FBX files for use in Unreal Engine.

Overview

The Export Face Board operator exports animation from the MetaHuman face control board to a binary FBX file. Unlike body animation which uses a hierarchical skeleton, face board animation exports a flat bone hierarchy — all bones are direct children of a single parent node.

Prerequisites

The rig instance must have a face board (face_board property). This is the MHC_FaceROM armature created by the Character DNA addon when importing a MetaHuman with facial controls.

Note

Not all MetaHuman imports include a face board. If the instance doesn't have one, the Export button is disabled in the UI.

How to Export

Select the rig instance in the sidebar panel
Open the Animation sub-panel
Click Export in the Face Board section
Choose a file path and name (default: {instance_name}_face_board.fbx)
Confirm the export

What Happens During Export

Bone list loading — Reads face_board_bones.json to get the ordered list of face board bone names. This file defines exactly which bones to export and in what order.
Document creation — Creates a new FBX document with the scene's frame rate.
Rest data collection — Reads rest transforms for the specified bones only (not the entire armature).
Animation sampling — Samples matrix_basis (raw animation data, not visual transforms) at each frame for each bone.
Flat hierarchy — Builds an FBX node structure where all bones are direct children of a single parent node named Face_ControlBoard_CtrlRig. No nesting.
Animation curves — Writes per-bone animation as Euler XYZ rotation (degrees) and translation. One take named "Unreal Take".
Binary FBX write — Encodes and writes the output file.

Face Board vs Body Export

Aspect	Body Export	Face Board Export
Hierarchy	Full skeleton tree	Flat (all bones under one parent)
Transform source	Visual transforms (`pose_bone.matrix`)	Raw animation (`matrix_basis`)
Scale factor	100× (Unreal cm)	1× (no scaling)
Axis conversion	Z-up right-hand	Default
Bone source	All body rig bones	Only bones listed in `face_board_bones.json`
Parent node	`root`	`Face_ControlBoard_CtrlRig`

The Face Board Bones File

The file resources/metahuman/face_board_bones.json contains an ordered list of bone names to export:

[
    "CTRL_C_eyesAim",
    "CTRL_L_eyeAim",
    "CTRL_R_eyeAim",
    "CTRL_C_eye",
    ...
]

This list matches the bone structure expected by Unreal Engine's MetaHuman face animation system. Only bones in this list are included in the export — other armature bones are ignored.