Anchoring feet

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gdeadtoo
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Joined: Thu Feb 23, 2023 4:51 pm

Anchoring feet

Post by gdeadtoo »

I created targeted Pin Bones on the shoes of my character, with each leg targeting the correct pin bone. But it's not behaving as expected. While the leg will move correctly when selecting the pin bone and moving it up and sideways, the pin bone is not anchored to the bottom of the leg bone. If I move it down, it separates from the bottom of the leg joint. I wish there was a way to attach a screenshot.

Any ideas on why?
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Hoptoad
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Re: Anchoring feet

Post by Hoptoad »

It sounds to me like you set things up correctly.

This may your problem: unlike other bones, target bones act differently on frame 0.

So do not test your target bones on frame 0. Set everything up on frame 0, but test your bone rig with target bones on frame 12 or whatever.
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Greenlaw
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Re: Anchoring feet

Post by Greenlaw »

There are two ways to deal with this.

1. Use Lock Bones.

2. Use Independent Angle on the foot bones.

Independent Angle is my preferred method. This method requires me to animate the rotation angle of the foot separately from IK, but this offers me a lot more control and it's less fiddly than working with Lock Bones. For example...

Image

Hope this helps.
Last edited by Greenlaw on Mon Dec 18, 2023 5:42 pm, edited 1 time in total.
gdeadtoo
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Re: Anchoring feet

Post by gdeadtoo »

Thanks!
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Greenlaw
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Re: Anchoring feet

Post by Greenlaw »

Another tip: You may have noticed that I use Regular bones for Target bones, not Pin bones. There's nothing wrong with using Pin bones but I prefer Regular bones because they're easier to grab and move in this situation.

Whichever bone type you use, make sure bone Strength is dialed down to 0 for the target bones. (Unless you have a reason to use bone strength there, of course.)
gdeadtoo
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Re: Anchoring feet

Post by gdeadtoo »

Thanks again
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Greenlaw
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Re: Anchoring feet

Post by Greenlaw »

For anyone still interested in this topic, I mentioned Lock Bone as another option for locking feet. This is the 'official' way to lock feet, and using it is straightforward. To use Lock Bone...

1. If you have Independent Angle activated for the feet, deactivate it.
2. Go to an animation frame and select a foot bone.
3. Click on Lock Bone in the tool options bar. The foot bone's position and rotation is now locked in place. Notice in the timeline that Moho has inserted a Lock keyframe.

You can test the lock state using IK by moving the character's root bone. The foot should stay locked in place. Now, skip to a later frame and unlock the bone. To unlock the bone...

4. Select the bone and deactivate Lock Bone in the tool options bar. Another keyframe is inserted but this one unlocks the bone.

The bone should now move freely.

The reason to use Lock Bone is when there is a need to keyframe the lock state of the bone. By contrast, Independent Angle is not keyframeable. Also, the Lock Bone approach doesn't require a target bone to lock the position of the bone.

So, why don't I like to use the Lock Bone method for locking feet? Because it's a pain to keep locking and unlocking the bone during animation. Also, I need to be sure to keyframe the bone position/rotation before unlocking the bone, or there will be a pop in the bone's rotation that needs to be fixed. This is what I meant earlier by "it's more fiddly."

So, yeah, for locking feet anyway, I think using Independent Angle with a target bone is a smarter way to animate because I only need to position the target and click once on the foot to 'lock' the rotation. No need to keep locking and unlocking anything.
gdeadtoo
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Joined: Thu Feb 23, 2023 4:51 pm

Re: Anchoring feet

Post by gdeadtoo »

Makes sense, thanks
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