How to rig eye pupils?

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Vanya_K
Posts: 4
Joined: Tue Jun 12, 2018 2:19 am

How to rig eye pupils?

Post by Vanya_K »

I am trying to make a bone that would be controler for the eye pupils so it can float around and be used to move pupils. I saw tutorials that suggested I put bone on each pupil layer and not parent them to anything. Than make a controler bone (also not parented) . All pf these bones 0 strength. So than in pupil bones BONE CONSTRAINTS i make that controler bone the one the controls both. So i got weird results. Like it works fine until i move character than my pupils fly out of his head. Obviously expected to happen as pupil bones are not parented to anything. So if i do parent them than my control bone gies crazy and moving it left right doesnt move pupils.left right it messes directions up because its controling parantes bones. So all of these tutorials are useless in a real life application. They work if you have only eyes in the shot. So dose anyone know legit way to do this or should I just animate pupil layers and not even rig them?
Thanks
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Greenlaw
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Re: How to rig eye pupils?

Post by Greenlaw »

There are many pupil rigging variations that work well.

In general, I like to create a Face bone to which I parent all the face elements, including the Pupil bones. This Face bone should have no Strength and it should be parented to the Head bone. This way, if I need to slide the face from side to side or up and down, like in head turns or up/down tilts, I only need to move the single Face bone to move everything. Because the Pupil bones are parented to the Face bone, they will always move relative the rest of the face, and you can animate each pupil relative to each eye.

For Pupils, I normally like to take this a little farther. I usually have all the eyes elements (white, eyelids, lashes, iris,) except the pupils, bound to separate left and right Eye bones. Then I have these parented to a common Eyes bone (no strength), which is parented to the Face bone. The two Pupil bones are then parented to the Eyes bone. This way, all the eye elements can move together and, of course, you can still animate the position of each pupil relative to the eye it belongs to. This bone structure also allows you to move parts of the face, like each eye, with a single bone...much easier than managing keyframes in multiple layers.

The number of bones in the face can quickly get cluttered, so I might use the Shy option for the bones less likely to be animated manually. In my setups, the Face and Eyes bone is usually animated in Head turn and tilt SBDs, so it's rare that I need to animate those bones directly. But if I do need to animate those Shy-ed out bones, the property can be easily toggled on and off using the Hide/Show Shy Bones command.

I worked with Victor Paredes on a couple of jobs last year, and noticed he does an interesting thing for pupil bones that I started incorporating in some of my rigs. Victor likes to position the pupil bones outside of the head. This helps minimize the face clutter problem, and it also offers common control for other pupil layers that may be in a different location, like in the profile view in a Switch layer. It takes a little practice to animate with the offset but it works well once you get used to it. In this setup, you may still want to parent these 'remote' pupil bones to the common Eyes bone or the Face mover bone, because you want to avoid having a different orientation for the parent bones.

If you want to keep these pupil bones 'unparented' from the rig, make a parent bone for each pupil bone that has the same starting orientation as the Eyes (or Face) bone. You can Shy this parent so it doesn't get accidentally animated.

You might parent this 'orientation' parent bone to an Anchor bone. I usually parent all my SBDs and control bones to a common SBD Anchor bone, that I may or may not attach to the character's root. This Anchor allows me to move the controls anywhere on the screen to avoid overlapping locations that make them difficult to read. If I do attach it to the character's root bone to make it move with the character, I like to enable the Anchor's Independent Rotation so it's not affected by the character's orientation changes. (Trust me, you really don't want your SBDs tumbling around with the character while you're animating it.)

The more I think about it, there are actually many, many ways to handle this, but maybe these suggestions will help get you started.

(Hope the above makes sense. I'm typing quickly because I'm zipping off to work soon.)
Vanya_K
Posts: 4
Joined: Tue Jun 12, 2018 2:19 am

Re: How to rig eye pupils?

Post by Vanya_K »

Thank you very very much for you thorough reply.
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