Combine multiple skinned meshes onto one skeleton

[TorQueMoD2]

I'm trying to bring a set of armor from Unreal into Max. Each piece of the armor is skinned to the identical skeleton, and I want to combine them all into a single max file with only one skeleton in the scene. Is this possible? Every time I've tried to merge a skinned mesh into a scene with the same skeleton, if I don't include the skeleton, it doesn't see the one in the scene as the same. and it just loses the skinning data. I've also tried adding the bones back to the skin, but same thing.

I saw a similar topic where the answer given was to use swin wrap, but this won't work if each piece is bringing in its own skeleton and there's a dozen skeletons in the scene.

[lauri_barnhart]

Hi @infoTJAKN,

I wanted to check in and see if you still needed assistance, or if you found a solution to your question already? Let us know if you need further assistance by providing an update or if you have found a solution, please share it with the community so other members who may have the same question could learn from your experience.

All the best,

Lauri | Community Manager

[TorQueMoD2]

No, I didn't figure out a solution. Was waiting to see if anyone else knew how to do this or if it's even possible.

[MartinBeh]

Can you break down what you already tried into smaller steps along with the results you got?

What keeps you from exporting all the armor pieces with the one skeleton all in one go? 

Or rather: why do you need to merge a skinned mesh?

I don't think you can directly "merge" skin data; you would have to export the weights for each skinned mesh separately, and then assemble a scene with all the meshes and bones in one scene, skin the meshes to those bones (with default weights) and finally import the exported weights for each mesh. 

Take a look at the Save and Load envelopes function in the Skin modifier, and also the Skin Utilities - maybe they have what you need? Also found this script to save/load weights.

Keep in mind that Skin modifier has multiple ways to calculate weights (e.g. normalized vs. non-normalized) so you might have to set it up correctly first in order to properly import data.

This probably will not work "out of the box" and require a fair amount of tinkering.

[TorQueMoD2]

In Unreal each piece of armor is rigged to the same skeleton but they're separate meshes so that you can dress your character with each piece like you would find in a typical RPG. There's no ability to combine the meshes on export. I was trying to combine them in Max because I'm not making an RPG where you can change your character's clothes. If I import a dozen meshes into Max though, there will be a dozen skeletons in the scene and there's no way to tell Max to not import the skeleton, but instead "Update" the scene to only bring in the mesh and use the skeleton that's already there. You can do this with an animation... if the animation FBX contains a skeleton and your scene contains the same skeleton, then you can choose Update and the animation will apply to the scene skeleton, but for some reason this doesn't work with skinned meshes. 
Combining the mesh pieces makes it more performant when I use it inside Unreal because each skeleton has a cost associated with it. 

Thinking about it more, I suppose what I could do is bring each mesh and skeleton into the scene and then use Skin Utilities to transfer the weights to mesh (vertex data) and then delete all of the skeletons save one and then reapply the saved weight data back to each mesh with the single skeleton. That might work actually. I'll try it.

[lauri_barnhart]

Hello, @TorQueMoD2,

Did the information provided by @MartinBeh help you and answer your question?

If yes, please click on the "Accept Solution" button on the post(s) that solved your problem. This will assist other community users in finding and benefiting from this information.

If not, please do not hesitate to give an update in this thread so all community members receive an update on the progression of your question, and can suggest next steps that may be helpful for you to achieve what you're looking for.

All the best,

Lauri | Community Manager

[TorQueMoD2]

Sorry, I don't know why I didn't reply to this comment directly. Transfering Envelopes doesn't work; I tested it and the results were worse than the default skin weighting. I didn't really change any of the settings though, so maybe there's a way I could get better results, but I don't know what the steps would be. 
The script you linked to is a paid plugin, so I don't have any interest in it. 

The Skin Utilities could work as I said in my follow up post via Transfer Weights to Mesh. I'll try that now.

[TorQueMoD2]

And of course, using Max 2026, Skin Utilities is crashing the second I click on "Extract Skin Data To Mesh". Ive tried it twice and it crashed both times. I remember using it in past versions of the editor, so it must be an issue with 2026. Yay!