Oftentimes I encounter a situation where I need to disable the Child of Constraint, adjust position of the 'parent' without moving its 'child' and then enable the constraint back in such way that the child stays in the place it was before its parent was moved. I cannot 'set origin' in the middle of the animation because if I do so everything that was animated prior to that will be spoiled. I just need to temporary disable the constraint so I could adjust position of the parent.
I'm animating a weapon reload. Left hand is constrained with the Child Of constraint to the magazine of the weapon from the beginning of the animation. That way the left arm follows the magazine which in turn is a child of the weapon. Now, in the middle of the action(animation) I need to drop the magazine, move it to the left hand outside from the view of the camera and insert it with the left hand back to the weapon so it would look like player reloads the weapon. The problem is that I cannot grab the magazine with the left hand. With the constraint enabled the hand moves along with the magazine (as expected). If I disable the constraint to move the magazine to the left hand and enable it back the hand moves away from it. I think there should be a way to calculate the offset with Python and adjust position of the hand from script?