4 replies to this topic

[danparkes]

We have a fully rigged skeleton (R12) which is working really well but have discovered we need to change the length of some of the bones within the rig (rather than the entire rig itself).

Can anyone point us in the right direction of how to do this without destroying the rig, as presently seems to happen when you start to alter the shape/size of any of the bones within it?  Is this because changes in length may alter the position of the joint?

Many thanks for any assistance!

[Horganovski]

It depends on the kind of rig you are working with really, is it an IK rig with controllers or a mocap-type file where there's just joints with animation on them on every frame? If the latter then you may need to delete position keys on the joints before adjusting the skeleton. Generally with mocap files you only need translation animation on the root (base of the spine usually) joint.


As a general rule to adjust the position of joints in an already bound character you do the following :

1- return the rig to it's bind pose.
2- select the skin deformer and switch it off (using the checkmark beside it in the OM) (the mesh should not move when you do this if you have returned the rig to the bind pose correctly)
3- move/rotate the joints to the new position.
4- select the Weight tag on the mesh and click the 'Set Pose' button.
5- now you can switch the skin deformer on again and the character is ready to animate.

HTH,
Cheers,
Brian

[danparkes]

Thanks Brian!

The rig has FK for the limbs and IK spline for spine, neck and tail, with FK local/world slider controllers.

I am not at all familiar with character rigging so appreciate your advice.

Many thanks

Dan

[atarigraffx]

I think if you delete the ik spine, readjust the size of the joints, and then re-do the ik spine. you shouldnt have any problems. just gotta get rid of any ik's first and then put them back in.

[Horganovski]

Technically you shouldn't have to delete the spline IK (with CD Tools rigs you can change the length of the chain and use the 'Set Length' function to set that as the new default length), but yeah, sometimes with Mocca rigs it's the simplest way forward, mainly if you are using the stretch option (Equal mode) in it.

Cheers,
Brian