Problems with looping in bone constraints

E.g, Bone A has a constraint α to copy the transformation of bone B, and bone B has a constraint β to copy the transformation of bone A, and then set the driver so that α and β will not be valid at the same time.

I think it’s ok in theory, but in practice it still throws some looping errors.

May I ask if this is a bug (the constraint cannot be effectively disabled?)
If not how should it be solved?

Hi Rb2CO3,

This is something that Blender cannot support right now. The evaluation of transforms has to happen in some order, and this is determined by, among other things, the drivers and their relations to other bones. Here the driver variables count; whether or not they’re actually used in the driver expression, or whether the expression is even valid, doesn’t matter.

I hope this answers your question.


ok, thanks for your answer.