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Importing 4.9's SK Mannequin into Blender; weird bone angles

Hey, I’m trying to get 4.9’s SK Mannequin skeleton into Blender so that I can build my characters off it. My workflow:

  1. Make third person template project
  2. Right-click SK Mannequin, Export -> FBX
  3. Blender set scene scale to Metric 0.01
  4. Import FBX in Blender -> Tick “Automatic Bone Orientation” (otherwise the bones would look VERY WRONG)

Seems to look alright for the most part, however, ik_hand_gun, ik_hand_l, ik_hand_r and ik_foot_root seems to be facing in some weird angle… is that normal? Doesn’t look normal to me at all… how do I fix that?

http://i.imgur.com/DQQSlZ1l.png

short answer, you dont really need to fix it. All animations should still work properly.

Thats caused by the difference between joints and bones (so Blender has to point in some direction) The IK bones are only used for point/look at type constraints, so you should be fine to re-orient them any way you like.

Got it, thanks!

Do note: when exporting your skeleton, you will have to delete the top-level IK_* bones. You must have only one top-level bone, or Unreal will not import your character/skeleton. This unfortunately breaks compatibility(AFAIK) with the default Epic Skeleton.

So does this mean that currently you cannot make animations in blender for the default characters, say the Third Person Mannequin?

Actually, disregard that. You will have to delete the IK_ prefixed top-level bones (displayed on the same level as the ‘root’ bone); but the animations should retain skeletal compatibility as long as you don’t delete any other bones or add any in the middle of a chain.

Note that Blender’s coordinate space is different than the skeleton’s, so your animations may not actually be usable. Some playing around with the orientation of your skeleton, blender’s export settings and the animation asset’s import settings may be required to resolve that.

If you can get that resolved, I would greatly appreciate if you would post the settings necessary to ensure coordinate-space compatibility. If not (as I fear may be the case), you will need to import your own skeleton.

Tangentially, there is a very slim possibility that you could retarget meshes based on the default Epic skeleton to your own imported version of the same skeleton, provided the bone structure and naming are the same. I have no idea how to do this, but it seems possible, what with talk of Skeleton Retargeting. Pure conjecture, mind you.

The pipeline works only well in the direction Blender to UE4 (up to Blender 2.75a). If you have some UE4 mannequin compatible skeleton in Blender you could create your animations in Blender and most should work well in UE4 afterwards. However it’s a pain to export something from UE4 with bones backwards to Blender (including the mannequin, animations, …). FBX seems to be not really GPL friendly and this is a huge burden for a solid FBX support for Blender.

I know its an old post…

I know this is kind of an old post… but for people searching in the future, I imagine that the people at Epic Games had designed this character originally with custom shapes for their bones. Animating with custom shapes makes the whole process quite a bit easier. If you go through and make custom shapes for each bone it may make the armature bone structure easier to understand such as a torus shape for most arm, digit, and leg bones. This helps tremendously with the most recent mannequin too.