Page 1 of 1

Rig inside of rig is being affected by parent actions

Posted: Fri Jan 30, 2026 9:58 am
by stephenthomas0
Stumbled across this today and have verified with everyone else working on the project. This is using 14.4, the bug doesn't appear in 14.3.

Nest one rig inside of another rig. Both rigs have Actions of the same name (e.g. 'blink'). The bone controlling the action for the parent also drives the action for the child rig inside.

Here's a screen recording of the bug with an ultra simple example: https://www.dropbox.com/scl/fi/ctkibmfb ... yh51v&dl=0

I'm going to submit an official bug report, but wanted to post this here too incase someone else stumbled across the same issue, took a good couple of hours to problem solve and finally figure out it was the software and not a rigging issue.

Re: Rig inside of rig is being affected by parent actions

Posted: Fri Jan 30, 2026 11:44 am
by Greenlaw
That's interesting. I don't think I've ever placed a full character rig inside another character rig, but I can see how this happens because Smart Bone Actions in a Parent's Bone layer can, by design, affect the actions/bones of a Child's Bone layer. I believe the system looks at the bone/action names, not the item's ID, so it might get confused. FYI, reading the item name in Moho is preferred in many situations, but it can cause issues in others. (Same with Layer names, which is why it's important to give layers unique, identifiable names when using Layered PSDs or Switch Layers. With PSDs, at least, Moho will default to using layer ID if it can't find a helpful layer name.)

I'm surprised to hear nested duplicate Smart Bone Actions worked in 14.3, but not in 14.4. Let me know if you get a reply from LM about this. I'll try some testing here on my own.

In the meantime, try giving the nested rig unique bone/action names. I think there are scripts available that can facilitate the renaming process. Check mohoscripts.com. I've used one to append and change bone names in a skeleton, and maybe there's one for Actions, too.

Hope this helps.

Re: Rig inside of rig is being affected by parent actions

Posted: Sat Jan 31, 2026 7:03 am
by Lukas
You could try nesting the sub-rig in a grouplayer that does not have the action. It might stop the action from influencing the sub-rig.

Be aware ‘entering’ the action from the top rig layer, will probably create the action on the mid-group. Which would enable the influence again.

(Not tested, but I’d assume this would work)

Re: Rig inside of rig is being affected by parent actions

Posted: Sat Jan 31, 2026 12:19 pm
by SimplSam
I think you are tremendously lucky that it ever worked 'OK'.

Actions are assigned per layer and then also per animation channel, and actions can have actions. Such that each Point width, Shape fill color, Layer position, Bone rotation, etc., etc., references its associated Action(s) independently, which can result in many thousands of Action references per project, all based solely on name.

As already mentioned, your best solution is to rename one or other action, ideally whilst the character rigs are in separate documents.

Re: Rig inside of rig is being affected by parent actions

Posted: Mon Feb 02, 2026 2:37 am
by stephenthomas0
Thanks for the replies everyone :)

Hey Greenlaw, yes, renaming bones & actions did fix it, but it was odd because this used to work fine without having unique names per rig. Someone on our team suggested the same about IDs, a bit crazy that it just looks at names which don't have to be unique... I did get a reply from LM and it wasn't great. The person looking at my ticket claimed that I'd sent them the wrong test file (I didn't). I tried to send them a reply with more details in the hope that it would help figure out what went wrong, but when I clicked 'submit' it kicked me out to the login screen and I can no longer log back in. All I wanted to do was provide information to try and help the devs figure out what's going wrong and make Moho more stable, but it felt very much like "This isn't a bug! Go away!" 😮‍💨

The really weird thing about this issue is that it stopped happening for everyone on the team at about the same time. Maybe Moho has some kind of cacheing system meant to speed things up that somehow temporarily stored this issue 🤷 Really weird.

Thanks for the suggestion Lukas, we did try putting the child rig into a group, but that didn't make a difference.

Thanks SimplSam... Something I'm learning more and more about Moho is that just because you 'can' do something, doesn't mean that it will work/is stable 😮‍💨 I went down a rabbit hole a couple of months ago trying to build an FK/IK switch into limbs. You 'can' set a parent to change in an action, but it always resulted in bones jumping/rotating randomly... The logic of what I was trying to do was sound and the workflow is there in the software to do it, it's just broken when you try to...