Problem with position control bone.

[burans]

Hey!
I'm attempting to create my first rig and am running into some issues.

I'm working on characters eyes and wanted to create a simple pupil position control.
I was planning to use position control bone under bone constraints to move a set of two pin bones by moving a controller bone.
The problem - this does not seem to work as expected if the pin bones I want to control are parented to a bone thats at an angle.
In my case they are parented to a bone thats at 90deg - when I move the controller up, the controlled bones move left etc.

Is there a way to make this kind of simple parenting/rigging work?
In most videos I've seen people use two smart bones to control pupil X and Y positions but that to me seems overly complicated. Not to mention creating a joystic using target bones.

Thanks!

[Daxel]

You can just parent both of the pupils bones to the control bone. Then moving the control will move its children, no constrains needed.

[burans]

You can just parent both of the pupils bones to the control bone. Then moving the control will move its children, no constrains needed.

Thanks!

I guess thats partly a solution. In this case I would need to parent the pupil control to the head bone also.
I was hoping to have all the controls separate from the character so they don't move around and can be positioned independently.

[Daxel]

I was hoping to have all the controls separate from the character so they don't move around and can be positioned independently.

Ah, now I get what you mean. One solution would be to create an additional bone starting from the head bone but looking straight to the right (you can hold shift while creating it to make it straight), call that bone AngleCorrector, parent the iris bones to the AngleCorrector and then make the AngleCorrector invisible or shy and forget about it. Make the Iris bones position controlled by the control bone and it should work like you want.

The only problem is that now you can't control each iris bone independently. To achieve that you'll need one more bone, an IrisMaster bone, controlled by the control bone, and parent of the two Iris bones. You could make the iris bones shy or invisible until you need to move them independently, to reduce clutter.

Another problem is that now if you flip your character main bone or your character's head, the control bone won't automatically flip so the control will be reversed (left is right).

Personally, I think that the simpler the better, and I don't see any reason to complicate things when two iris bones parented to the head bone work well. When I need to move both of them, I just select both and move them together. And it doesn't matter how much I move the bones of my character I never have to find where my iris controllers are, the iris bones are always where the head is and that's it.

[Greenlaw]

Personally, I think that the simpler the better...

I agree, simpler is better...especially when you have a lot of work to get done in a short time.

IMO, using a Smart Bone Dial or multiple Smart Bone Dials to simply reposition the eyes is cumbersome to work with. Using a Smart Bone Dials for this also limits you only what the control is capable of. This can result in somewhat 'robotic' looking movements.

I've been using Moho in production for many years, and I never bother with Smart Bones to control eye position. I prefer to add a Face bone and parent that to the Head bone, and then parent all the face-related bones, including eye bones, to this Face bone. This gives me a handle to move the entire face or any subset of face bones (like eyes) individually. This is a more direct and precise way to animate any part of the face quickly. Tip: If I want to animate both eyes together, I just add a shared parent and animate that...though I don't usually bother with this either because I rarely find I want to move both eyes in equal distance.

Of course, having all these bones in the face can get cluttered in that region, so for eyes I like to create external bones to 'remote control' their position from outside the head region, and then I shy the actual eye bones to reduce the face clutter. Use Position Constraint to do this. Some old Moho content, like the Gorilla rig, use a similar setup.

Update to this post: Using remote control bones also easily solves the problem with offset eye bone positions during a head turn. With remote bones, since I'm working with bones that are offset much farther by design, the offset problem at the actual face region isn't noticeable.

Smart Bone Dials are very useful but I try to reserve them for complex motions that are truly tedious to animate over and over again, like head and body turns. In the case of eyes, I use Smart Bones to control blinking and pupil size. Sometimes I may set one up of for changing the shape of the eye (like upward or downward angles.)

But for eye position? Its easier for me to just drag a bone to exactly where I want it to be.

Hope this helps.

[burans]

One solution would be to create an additional bone starting from the head bone but looking straight to the right (you can hold shift while creating it to make it straight), call that bone AngleCorrector, parent the iris bones to the AngleCorrector and then make the AngleCorrector invisible or shy and forget about it. Make the Iris bones position controlled by the control bone and it should work like you want.

Thank you! This workaround worked great!
I'm not planing to flip the character so that's not an issue for me.

Thank you!