Metahuman for Maya - Metahuman Pose Editor - Missing drivers: {'calf_l'}...

[Mike_Fudge]

Hi,

I’m unable to load anything in the Metahuman Pose Editor. My workflow is simple and is as follows:

In a fresh thirdperson unreal 5.6.1 project create a new Metahuman Character asset. Select the Aera preset, Create Full Rig, Download Source textures, Assemble the scene for DCC export. Open maya and assemble the character using the menu from the Metahuman for Maya plugin, Open the Pose Editor and Import from DNA, select the body the DNA file exported from Unreal.

The result is nothing, nothing loads in the pose editor. Output log is at the bottom of this post.

How do you correctly load the data into the Metahuman Pose Editor? I’ve used pose wrangler in the past and expect to see similar data in the menu but I’m not seeing anything.

This looks like a cool workflow but I cannot get it to work. Any help is appreciated!

Thank you.

After importing the body dna, nothing is updated in the scene or pose editor window and the outliner shows this:

# Warning: Plug-in, "SwingTwistEvaluatorPlugin.mll", is already loaded.  Skipped.
updatePluginCallback();
// Warning: EpicGames.PoseEditor : Missing drivers: {'calf_l'}
// Warning: EpicGames.PoseEditor : Missing driven: {'thigh_twistCor_02_l', 'thigh_twistCor_01_l', 'calf_twistCor_02_l', 'calf_kneeBack_l', 'calf_knee_l'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'calf_r'}
// Warning: EpicGames.PoseEditor : Missing driven: {'thigh_twistCor_01_r', 'thigh_twistCor_02_r', 'calf_twistCor_02_r', 'calf_kneeBack_r', 'calf_knee_r'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'clavicle_l'}
// Warning: EpicGames.PoseEditor : Missing driven: {'spine_04_latissimus_l', 'clavicle_out_l', 'clavicle_scap_l', 'clavicle_pec_l'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'clavicle_r'}
// Warning: EpicGames.PoseEditor : Missing driven: {'spine_04_latissimus_r', 'clavicle_pec_r', 'clavicle_out_r', 'clavicle_scap_r'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'foot_l'}
// Warning: EpicGames.PoseEditor : Missing driven: {'ankle_fwd_l', 'ankle_bck_l'}

...And so on for every bone...

// Warning: EpicGames.PoseEditor : Missing driven: {'thumb_02_half_r'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'thumb_03_r'}
// Warning: EpicGames.PoseEditor : Missing driven: {'thumb_03_side_out_r', 'thumb_03_side_inn_r', 'thumb_03_bulge_r', 'thumb_03_in_r', 'thumb_03_pip_r', 'thumb_02_bulge_r'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'thumb_03_r'}
// Warning: EpicGames.PoseEditor : Missing driven: {'thumb_03_half_r'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'upperarm_l'}
// Warning: EpicGames.PoseEditor : Missing driven: {'upperarm_fwd_l', 'upperarm_twistCor_01_l', 'upperarm_twistCor_02_l', 'upperarm_in_l', 'upperarm_out_l', 'upperarm_bck_l'}
// Warning: EpicGames.PoseEditor : Missing drivers: {'upperarm_r'}
// Warning: EpicGames.PoseEditor : Missing driven: {'upperarm_in_r', 'upperarm_fwd_r', 'upperarm_out_r', 'upperarm_twistCor_01_r', 'upperarm_twistCor_02_r', 'upperarm_bck_r'}
// EpicGames.PoseEditor : Successfully loaded D:/_3d/Metahuman/MHC_Asian_Preset/body.dna

[Mike_Fudge]

It appears I have to load the DNA through the pose editor from an empty maya scene. But if I already have a maya scene character setup (as done above) how do I access that characters RBF solvers? I was hoping this tool would open RBF solvers on whatever was already open in the maya scene.

Something like Metahuman tool panel Character Assembler > Load character > Pose Editor > Load and edit poses > Export DNA > Import to Unreal with updated RBF’s.

Do I have to work on the body and head separately, export and updates as DNA files, import that into unreal, reassemble and export to maya, assemble the character in maya so check the results on the full character?

I’m hoping someone can come along and correct my expectations of workflow.

[anonymous_user_3dbeb1611 (clamdragon)]

It has been months since you posted this, so I’m sure you either solved it or found some workaround. But in case anyone else finds this thread while wondering this same thing, here is what I have been able to learn from muddling through:

The following applies to version 3.4 of the plugin in Maya 2025 and an unreal 5.7 metahuman environment.

As noted above, the pose editor must load a .dna file from an empty scene. You then use it to edit desired poses, then re-export a .dna file. Then, back in your main scene with the “Assembled” metahuman skeletal mesh, there will be nodes called “body_embeddedNodeRL4” and “head_embeddedNodeRL4” or similar. These are the pose drivers, but the actual poses are not stored on this node. Instead, they have an attribute that wants a path to a .dna file, so it reads the trained pose model from that and does the calculations. I hope and assume this is so you can polish poses as you like once, then use those polished poses across multiple characters. So, you put the path of your re-exported .dna file into this attribute and the mesh should deform as you want.

In an oversight than can only be described as Epic, they decided to not allow environment variables in the .dna file path string. Maybe next release.