Operating system: Windows 7 64-bit SP1
Broken: any 2.80 beta build
Worked: Only in 2.79 (which is obviously the stable version)
Short description of error
It appears that the coding for the copy rotation constraint is not complete. its also missing some useful features for making animations.
The following bug I noticed is the fact that copy rotation constraint (and probably the other copy constraints) don't seem to do their job while the animation is being rendered only if the bone has a child as target instead of a parent. If target is a parent then everything is working fine
Exact steps for others to reproduce the error
- create a bone armature, and extrude a number of bones (not too many)
- give it a copy rotation constraint (or the other two)
- make sure the target is the child bone, and not the parent
- make a simple animation test for it by transforming the bone that uses the constraint.
As you can see the constraint seems to be doing its job completely fine on viewport, but when you will render the animation, only the bone with the constraint will rotate, the target will do nothing.
And btw, about the "useful features". If you choose the make a child bone as target in the bone constraint, the behaviour will be different. Instead of the constraint transforming the bone in linear style, it transforms it dynamically. And by that I mean that the bone with the constraint will copy the target's transformation more dynamically.
So, I was thinking if there would be a possibility if there was a option that could change the constraints behaviour to control the bone more smoothly/dynamically.