I've added IK constraints to the leg bones. The question is do I need to add constraints to the other bones(head,neck,tail...) ? and if yes how ? like for the head where should the IK target be positioned? Thanks in advance.
Hey Oth, I'd recommend setting up IK only for areas that you need to remain steady regardless of the movement of the other bones. The head of an animal might be another good place to IK since it often stays fairly steady during a run cycle. The tail, however, follows along with the body and not the other way around, so there's no need to IK it. only the bones at the end of ligaments need to be IK'd, so the neck won't need it since it'll be controlled by the head's IK anyway and it's right in the middle of the chain.
Thank Jonathan so much for replying. sorry to bother again, but I have another question. I extruded the IK target from the tail of the head bone and IK pole from the head of the bone as you can see in the picture. Is that correct ? And must the IK constraint have a pole target ? I tried to move the pole target and it almost did the same job as the IK target. Is it redundant in this case ?
Thank you
IK constraints do not require a pole target, but they can be useful in some situations. For a head target, I would not use one unless there were quite a few bones in the neck also under the influence of the IK constraint.
The target bone cannot be parented to any bone that the IK constraint is acting on (this is determined by the chain length of IK constraint) or it will go crazy. Extruding the target bone from the head bone is OK as long as the target bone is reparented to another bone like the chest, hip or root bone.
Good luck!
Thank you Dan. Is it OK if I don't parent the target bone to any bone?
In the tutorial Kent did "clear parent" to the target bone after extruding it and didn't reparent it.