So, for some reason DEF-spine.003 is picking up rotation from ORG-spine.004. If I rotate the neck control, vertices on the chest rotate. It’s the vertices assigned to DEF-spine.003. If I delete the DEF-spine.003 vertex group, the vertices return to their home position, so that influence is the problem.
I’ve tried deleting all constraints and relations on DEF-spine.003. Nothing seems to separate it from ORG-spine.004, which is getting its rotation from tweak_spine.004. The only way to fix the problem is to turn off the Copy Transforms constraint on ORG-spine.004. This seems to work OK, but it also disables the tweak_spine.004 control.
Turning off or deleting both bone constraints doesn’t seem to have any effect whatsoever, nor turning off everything in relations, nor even unparenting DEF-spine.003.
Any ideas on why ORG-spine.004 has any influence on DEF-spine.003 so I can sever it?
You can see in the video exactly which vertex groups the vertex is assigned to. You can also see when I set the vertex group weight for DEF-spine.003 to zero, the vertices go to the rest position.
There is no neck influence. There are no non-DEF vertex groups. This problem just started with 4.0. And it’s weird because there’s some hidden connection between ORG-spine.004 (neck) and DEF-spine.003 (chest).
Nope. That one is freshly regenerated. It’s a problem in the Rigify Generate Rig construction script. There should be no backward hierarchy relationship between DEF-spine.003 (chest) and ORG-spine.004 (neck). But when I turn off the ORG…Copy Transforms constraint, the problem goes away. But then tweek_spine.004 no longer works for rotation. Can still use it for stretching.
I’m wondering if it’s a driver somewhere that I can’t see.
Edit: if I unparent the DEF-spine.004 bone from DEF-spine.003, it also appears to address the problem. Maybe solves it. I can just disconnect the bone, and that works. It stays connected to the body through its copy transform constraint.
Yeah. Only problem with that is it disables the tweak control. Which isn’t that useful. But it does serve a purpose.
The DEF-spine.004 bone seems to be the problem. It’s connected to DEF-spine.003 and for some reason, rotating .004 rotates .003 when connected.
I discovered last night that if I use unparent and use the disconnect option on DEF-spine.004, it solves the problem and the tweek_spine.004 control still works on the neck.
Because DEF-spine.004 has a Copy Transform constraint, it doesn’t need to be connected to …spine.003.
Weird. I guess I should call this solved?
I’m planning on writing a fix-it script for regenerate rig. I’ll have to add unparenting/disconnecting DEF-spi e.004 from DEF-spine.003 to the list of operations.
I got the same issue these days and find a simple way to solve it. Get back to metarig , select spine.004 in pose mode ,switch to bone properties , unfold rigify type , uncheck connect chain , regenerate rig.
I think the issue is caused by B-bones instead of weight.Because in my case ,the weight of chest was painted evenly from neck to belly,but when i rotate neck bone,chest rotates smoothly,which is not matched to the weight.
