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Is there a way to Lock Bone Rotation to prevent influence by IK?

Is there a way to lock Bone Rotation to prevent influence by IK? It appears Daz3d Genesis 8 Limb Twist Bones midway that are being influenced by IK. The Limb Twist Bone { lrThighTwist, lrForearmTwist, lrShldrTwist } are bending and distorting the Mesh with IK handling. I want to lock these bones in place so there is no bending. However, I’m having difficult time finding the Skeletal Control Node to do this. Open to recommendations. Video Attached. Thanks in advance.

https://youtube.com/watch?v=uEmgY8CF648

what if. After the animation IK nodes you reset their position with a transform modify?

I’ve considered this. I also considered taking a snapshot of the transform on initialization, then calculate and apply the difference. However, i anticipate this will alter the IK influence where its needed. Hoping that theres means already to lock the bone.

So, by the looks of it (your vid). The skeleton is not “epic” friendly.
thats fine ofc. however I would suggest modifying the rig since the issue is likely to be just parenting. Not positioning. I’d have to play with it to be sure, but the point is, the bones are connected yet should not be.

The IK node takes in the chain. If the bones are part of the chain they get calculated. If they arent then you wouldn’t get any issue.

So the real answer is change the skeleton.

The “I wanna stick with the default because I need to work on it a lot and I’m lazy af, noob and have no idea what that chain bit you mentioned is, or daz is always right so you are wrong” answer is:
Try to expand the bones in the chain.
obviously 2 bone IK won’t work right on 4 bones.

You have Leg IK node, or Fabric as alternatives.

Ps: thats a pretty funky walk isn’t it??
your vid stutters, but the IK is causing all sorts of bends that shouldn’t be happening at a glance.glance from the obvious one you see.

Pps: bones definitely do not bend. Not IRL nor in engine… they don’t flex either. They pivot/swivel That they do.
the hands are likely affected by the same issue. The chain is 4 bones instead of 2.

Its True, *I wanna stick with the default because I need to work on it a lot and I’m lazy af, * However, I’m desperate and did make an attempt to remove the twist bones in blender and ended up braking the morphtargets. I appreciate your insight on the IK effect on bone chain. This gives me some ideas on possible changes to IK. I appreciate you taking time to answer.

I don’t see how “disconnecting” a connected bone would change a morph target, but all IS possible.

The baseline idea is. Disconnect the twist bone leaving its offset.
in fact. Screw connected bones. Disconnect them all so that its similar to the mannequin. You just need to change the parenting afterwards to best match the ue4 hierarchy.

The skeleton itself relies on bone parenting, not their connection settings (but you can’t change parent if connected in blender).

So yea, disconnect the bones by unchecking the checkbox, and mimic the ue4 parenting while preserving all positions.
That should put it back in working order and provide compatibility with the epic skeleton for retargeting.

I’ve elected to not modify the skeleton in DCC. I’ll play with the IK, VBs, and Skeletal Controls til find a solution. I truly appreciate you taking time to provide your insight and recommendations.

I know it’s been a while in this thread, but just for anyone else that had this issue, especially for the genesis8 from daz.

I haven’t tried it with the legIK specifically, but for armIK (and the hiarchy-problems there are the same) you can fix it by creating a custom hiarchy with virtual bones.

from the collar you create shldr->forearm->hand virtual bones. Then where you use the IK you use the virtual-bones as the effector and targets. After the IK is calculated you can then copy-delta (copy works too, but delta with the copy-option gave me better results) only the rotation from the virtual bones over to the bend-bones from the daz-hiarchy.
This way i had fine-working ik without twist-bone interference, but also the twistbones did not cause any issues onto the mesh.

Hope this helps someone. Cheers o/