Im having an issue where if i import an animation from ue4 in to 3ds max everything displays correctly with the bones visable, but after being exported from 3DS Max and reimported in to 3DS Max im left with just the dummys for the bones like in the image below.
Which is making it very difficult to change animations after the first import, has anyone got any ideas whats causing this?
This happens because Max does not consider helper objects as bones.
The first time you import FBX they come in as visual presentations of bones in max but what hey arein fact are just connected point helpers that max recognizes as such and not as bones. So when you are exporting them out again form Max they come back in the same only the visual presentation is more accurate in the veiwport and they get displayed as dummy helper objects that they always were.
To solve the issue you need a script to connect the dots with Max bones and recreate the chain for you, this may cause further problems down the line if the script isn’t customized to your specific bone chain. Plus you need another object to bake the bones with the same keys.
I suggest to take the little extra time and do the following:
1 - import this bone chain FBX from the exported max so they come in as dummies. in T pose.
2 - go through each dummy and connect them by creating a new bone chain and root bone one at a time with Max bones. Link these accordingly so the Hierarchy of the new bones match those of the dummies.
3 - make sure max bone names are the same as corresponding dummy bone names and that the bones are properly aligned and positioned to the pivot of these helpers (use align tool).
4 - after this you will have a clean bone chain with same naming conventions and hierarchy in Max. Next time you can just import your FBX files and use Animation - Save animation tool in max Menu to save out the FBX animations and load them on your new rig.
You will be able to do this for all fbx motions as long as they have the same naming conventions and bone Hierarchy.