I created a custom character, imported the ue4 mannequin skeleton into 3ds max and used its bones just adjusted their positions and added some facial bones and breast bones to it, but the naming scheme is the same. did a pretty good skinning job if you ask me, and yet the retargets in UE 5.4 are turning awful.
my character’s proportions are stylized, but nothing major for the result to be so bad. I’ve retargeted third party characters before and always had a good result. I’ve tried several different animation packs and the result is always the same. my character looks like it has a hunchback, more prominently, but some other issues are noticeable, the arms are usually way behind where they should be, the entire back is arched, etc. I tried offseting neck and head bones position in 3ds max to both sides, from a little to extreme offsets, but the result is always the same.
can you be more specific about what is not working. can you show your re target asset with like default_walk anim to get some more specifics about what might be happening.
Max should not be the direct culprit here as Unreal is just reading the 3dmodel data from the file imported; it doesn’t particularly care which program you used to make it as long as it is a file type that Unreal understands so GLT, or FBX for best results (technically Epic in house uses Maya, but even Blender models are supported just watch your export settings).
Maybe check your export settings, maybe an update happened and something went to a default.
For the head the final bone in the chain Unreal kind of expects it to be in line with the spine bones (at least parallel to them) and in most cases pointing directly from the last spine bone through the crown.
for your face rig maybe having it come off of one of the lower bones in the chain (at least like 1 or 2 bones from the “Head” bone)
the re targeting system expects the number of bones, length of chains, and general pose to be “similar” what this generally means that you “should” have the same number of leg, arm, spine, and hand/finger bones, as well be able to almost put the models on top of each other for their rigs.
with that being said the system has gotten “better” like being able to re target A-Pose rigs to T-Pose rigs (I think starting in like ue5.1) though it still works best with rigs that have similar bones in per chain. even after a few adjustments to a Mixamo Model (changing the root bone) being able to retarget that from Manny)
it’s no so much that something isn’t working, but the retargets making the character look hunchback, her head always pointing down, positioned too much forward, her neck tilted forward, her upper back arched, while I don’t see any indications on the unposed model that would lead to this behavior.
Here are the standard animation demos (forgive me for the bare skin)
in the retarget asset make sure that when you do the bone chains for retargeting for the Head make sure you DO NOT select the ones for your face rig. having it be a child of a bone higher in the chain will allow it to be ignored easier, and make things like animation layers easier later, so the model/character can like walk and talk.
make sure that the “breast_bones” are being ignored by the retarget asset for the spine chain; maybe the engine is over-correcting forcing the “shoulder blades” backwards to average out the point between breast bones and the spine at that point, and forcing the midpoint to the location of the spine
in your model in Max the bone Labeled “head” point it directly to the center of the crown (it should have not children), so if that means adding a new child fine there should be only one bone named Head as well. put the face rig as a child to a bone besides “head”.
in Max try to overlay the UE rig’s spine on top of your models spine I have a feeling you shifted the bones backwards in the spine, and forwards in the shoulder, and the lower number of vertices is just exaggerating it.
do a pass on in weight paint mode (search for like “3ds max weight paint rig”) checking all the bones from above the clavicles to ensure they are not influencing the model’s upper back “too much”. it might be that the “breast_bones” have to much influence to the shoulder blade area and it is the model overriding the animation.
in the retarget asset you can fine tune the pose through constraints so that it will generally match better, and is often on an animation by animation, pose by pose basis.
To lessen problems your bone rotations, axis (and thefore roll/pitch) have to match exactly between the two skeletons before being weighted onto the weight paint.
In blender you can hack your way to the right rotations by editing the armature in edit mode and setting things where they should have been.
After that, a simple export/re-import to update the skeleton will likely adjust/fix issues.
However the epic animations are just bad - the reason it’s not immidiately evident on the mannequin is that its split off into parts which are weightpainted differently than you would weightpaint a humanoid skin…
From all the usual templates since UE4 I realized that their animations are bad, but I’ve tried several third party animation packs, and the results are the same. I tried the same animations with third party characters from the market place, and they all seem relatively fine, but my model has this weird neck/back issue.
to me it seems to be a mismatch between my skeleton and ue4 mannequin’s skeleton, and the auto retarget system not liking that mismatch. most animations seem to be based on the epic skeleton, just like most characters on the marketplace are optimized to use, or be compatible with that skeleton.
I’ll try to align all the joint rotations, in max I suppose I can just disable “always deform” and do any adjustments I need to. Thanks!
the automatic part is a first pass “best guess” by the engine. like many “automagic” things you can still go in and fine tune it. for your case they don’t directly expect a face rig and/or breasts, especially going from the UE4 skeleton to the UE5.3 skeleton which added support for things like face rigs from MetaHuman.
the Automatic portion is based on “expected” rigs from specific verndors that are generally consistent in their structure (doing all the things you would end up doing in other tools or in making a retarget asset)
try selecting one of the animations you are interested in, right-click select “retarget Animation” then you will be able to go through the process of the previous retarget system where you get a lot more control. you can also do this from a more blank sleight by in the content browser creating a retarget asset (I don’t have Unreal open right now, but I think it is under animations)
the reason that many animations from the market will give you similar results is one of the expectations is they work with the standard control rig (so Manyy and Quinn) so any “bads” with those rigs will be in those as well.
You can try to change the skeleton settings from skeleton to animation scaled or any of the other options to see if it makes any difference to the final product.
Usually with custom rigs and animations you always do animation scaled - particularly when no retargeting is required.
Alright! So I tried about everything, and with your suggestions I was able to pinpoint the exact thing that was causing the issue.
First of all, I was using the auto retargeter and not creating retarget assets, but exporting the animations directly. So one of the things I tried was creating the ik rig and ik retarget assets and exploring them.
The auto system wasn’t considering breast and facial bones as we suspected to be one of the issues, but it was doing something odd: instead of using the clavicle bones as start for the arm chains, it was starting from the shoulder bone, and creating “clavicle” chains with only the clavicle bones in it. this was causing the arm position issue, and some of the upper back arching.
Similarly, the head chain was composed of the single head bone, and an additional neck chain was created, containing the only neck bone.
I merged the neck and head bones into a single head chain, deleted the clavicle chains and added the clavicle bones as start for the arm chains.
this fixed about 95% of the noticeable issues as you can see from just the base pose:
after that it was just a matter of fine tuning and manually positioning the bones to match the source skeleton pose, and I can’t notice anything wrong.
I hope this helps anyone else having similar issues. Thanks for all your help, folks!
