I am attempting to retarget animation from the UE4 Mannequin to a metahuman character, which has been mostly successful. The problem I’m having though is that my metahuman is around a foot shorter than the mannequin. While the animations do play and seem to look okay for the most part, the IK hands aren’t scaled. They are at the same height as on the original skeleton, this means that on the MetaHuman the hands rest oddly high creating an odd stance where the smaller characters elbows need to be much more bent to get the hands to the target position, also when crouching the hands are so high the MetaHuman almost has their hands over their head.
If I could find a way to scale the UE4 Mannequin down by around 10% before retargetting the animation I think everything would be fine but I have no idea how to do this.
Can anybody advise?
Hey @GreatShatner
Do both characters have the same starting pose?
I believe so.
Can you show a screenshot from your characters in the retargeting window where they stand next to each other
See how they’re different heights. That seems to be the problem. The IK goals are just too high once the animation is retargeted.
Do you have IK goals on both characters at the same position?
I don’t know. Presumably the ue4 mannequin and metahuman skeleton have ikgoals on them, are they in the same position? I don’t know, but I would assume not since the characters are different heights.
I mean if you added them for both in their bone hierarchy. The scale / height should not be a problem:
The problem is that Target Mesh Scale also scales the positions of the ik goals. The strange posture remains, the character is just bigger.
Look at this screenshot, notice how high the right arm is. I’ve scaled the target mesh as you suggested but as you can see it just scaled the whole rig. The reason the arm is so high is because the metahuman is shorter than the mannequin, and the ik goals remain in the same position when retargeted so the arms end up far too high up.
Like I said, if you could scale the mannequin down a little before retargeting the hand iks would be in the correct position, but I don’t know how to do that.
Was there a proper solution discovered yet? Retargeting is an imperfect process but for sure I was hoping Epic had designed the IK goals to scale appropriately when we scale up the intended target mesh. Just as stated above if the target character scale is too different from the source character the IK goals are almost entirely meaningless as they do not proportionately scale with the intended target mesh in a way that more intuitively aligns it with the source Manny/Quinn/UE4 Pawn. When I have tiny characters I want to retarget I up scale them illegally in Maya to make em fit the scale of the Quinn skeletal mesh then I just scale them back down inside of the third person blueprint but this is not ideal at all and affects other assets like physics bodies etc.
Third person template comes with IK rig templates for UE4 and 5 mannequins. Replicate their setups in your IK. Remember to use the Full Body IK. Then the height difference issue should be reduced.
