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Metahuman Maya transform does not match UE5

Hi all,

I’m having trouble with getting objects from the Metahumans Maya 2020 scene auto-created by Quixel Bridge to line up properly with my Metahuman in UE5:

Both of these objects are at world 0,0,0 in Unreal. As you can see, the box I exported that’s the exact height of the Metahuman in Maya appears be a fair bit taller in UE5.

This is using a new, clean Maya scene created for me by exporting the Metahuman from Bridge. No extra transforms have been applied, no changes to the Metahuman model or rig.

Is it possible the metahuman scene generated by Bridge is offsetting the models somehow? Or is there something on the Unreal side that is scaling or offsetting the Metahuman somehow? I’m trying to make custom grooms and clothing for Metahuman models, and they need to line up pretty precisely for the Maya workflow to be of any use.

For starters I’m pretty sure the left side is orthogonal and the right is perspective. That can cause discrepancies in how the model looks.

Have you tried exporting the MetaHuman from UE4 and importing it into your scene to see if there is any difference between the two?

You are correct: the two images are ortho vs. perspective, so I’m sorry for that being misleading, but I can assure you that the box mesh imports approximately with about a 2cm gap between the top of it and the very top of the skull, whereas in Maya the two are lined up perfectly.

I liked your suggestion of exporting the UE5 mesh into Maya and seeing if the two are any different in the scene. This was what I got:

The dark grey mesh is the metahuman skeletal mesh exported from the engine (asset actions > export). Looks like it transfers back to Maya with the expected offset.

It’s enough to work with to make custom clothing and grooms for the metahuman that line up with the model, but I’d really like to figure out what’s happening with the original scene and why this offset is happening so I don’t have to export things back and forth in the future just to get them to line up.

Oh I wasn’t trying to imply you were misleading with the ortho/persp viewports. I just know that it can cause distortion to a certain degree.

Looks like you’re correct though in the discrepancy between the two models. So it would appear that the in engine metahuman is sitting below the gridline?

My first thought would be that I remember some Epic Paragon assets having slight offsets in their character blueprints. But then, that shouldn’t be translated when exporting a skeletal mesh from the engine as that’s local to the BP.

I’d probably go with the engine version of the character though for the time being as that’s what most people would be using. There seems to be some weird issues with the bridge export process, not just with this but even with certain attributes of the metahuman not being exported properly (the teeth are default when exported, no matter how you modify them).

Unfortunately there hasn’t been much public acknowledgement of these issues but I hope the team is at least reading these so we can get some fixes down the line. =)

Yeah, over the last couple of days my workaround has essentially been to export skeletal mesh content directly from the engine, and work on top of that for anything that needs to actually line up precisely to the character. There’s a convenient head-to-toe preview mesh in the Common Metahuman folders that has the full skeleton that’s useful for skin-wrapping clothes, and the second export from the engine in my last post was useful for making sure hair groom content is perfectly aligned.

I scrubbed through the engine content, the skeletal mesh assets, metahuman BPs, etc. trying to look for any offsets, but couldn’t see anything that should be affecting the models in that way. Maybe something in the rigging/default pose shifts slightly? A bit like trying to find a needle in a haystack.

Really hope the MH team can look into getting the maya source file generated by bridge to be useful as a modelling source file. It would be a fantastic workflow enhancer to be able to work on top of a metahuman and have everything all matched up perfectly for export in the engine. I understand its primary function at the moment is creating animations with the control rig shapes, but I’d love it if everything in the scene (bone heirarchy, transforms, etc) matched up so you could do stuff like create custom blendshapes for the metas.