Attaching+ morphing grooms. Having serious difficulties

Development Character & Animation
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1

Hey all,

I’m trying to add a full hair groom (hair, beard, eyebrows) to my character.

I’ve done this before by just attaching the groom to the head in the object outliner, but now I want the groom to conform to the face as the character changes his expressions. I.e. when he raises his brow, the eyebrow groom lifts.

I found this old post that seems to address thisissue. Can you attach hair strands to blendshapes? - #10 by falconking1111

However, it looks like I need to create a binding asset for my groom, and when I go to create one and select my skeletal mesh, I get these errors.

LogHairStrands: Error: [Groom] Binding asset could not be built. The target skeletal mesh could be missing UVs.
LogHairStrands: Error: [Groom] Binding asset could not be built. Some strand roots are not close enough to the target mesh to be projected onto it.
LogHairStrands: Error: [Groom] The binding asset (testavatarhair_test_cover_avatar_Binding) couldn’t be built. This binding asset won’t be used.

Any idea what’s happening?

I imported my character straight from Character Creator 4, if that makes any difference.

2

So, update. I WAS able to create a binding asset. I just had to reimport my groom. I have no idea why, but there it is.

It still didn’t work, but then I went into project settings and changed Default Skin Cache Behavior from exclusive to inclusive.

And it works beautifully! When unreal works, I absolutely love it. :grin: :laughing:

3

Adding to the knowledge base…

I ran into this issue as well (unable to create Binding asset).
Using UE5.1 and XGen Hair from Maya 2022.

My fix was to import the Hair again so it lines up with my Skeletal Mesh I was targeting.
:point_right: Had to do the rotations in the Groom import dialog:
Rotation: x = -90, y = 0, z = 180
Scale: x = -1, y = 1, z = 1 (scale negative in X because hair is flipped).

Then I was able to right-click Groom and Create Binding with no problem. Even sticks to the mesh on morph target blends. Works great!