Bone and X/Y scaling problem.

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Kiiryu
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Bone and X/Y scaling problem.

Post by Kiiryu »

This requires a little explanation

Basically, I'm trying to make a head rig capable of easy head turns via layers and scaling.
https://i.gyazo.com/1dab1b98cf1ef286244 ... e7e4c4.mp4

First I tried with a lot of manual vertices shifting, but it's a little too time consuming, and all the keyframes end up being on different layers, so it's not really practical.

At the very least, I'd like the moving and scaling of major parts to be done with bones, so that I can have all the major rotation stuff done on a single set of keyframes before doing minor corrections if I need to.
https://i.gyazo.com/68a9d5107119946579c ... 9b8c85.mp4

However, to do looking up and looking down, I also need to be able to scale things vertically, which is where I hit a problem.
https://i.gyazo.com/a2a6eca629178e21fe2 ... 0abea2.mp4

If I assign a layer to the two bones for flexi-binding, the bones begin to affect each other even though they arent parented to each other. If I don't use flexi binding,
then I run into problems because all the parts are in the same bone group. (for example they start affecting each other)

So what I need to know is, how can I have a vector layer height/width/position control via bones? Keeping in mind that anything that causes each part to have a different set of key-frames is not an option.
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Greenlaw
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Re: Bone and X/Y scaling problem.

Post by Greenlaw »

That looks like a very complicated setup. IMO, it could be better to do this sort of thing using a couple of Smart Bone Dials.

For example, a single Smart Bone Dial using only two actions can be used to turn the head left or right, and a second SBD with two actions can be used to tilt the head up and down. The actions for each dial can include all the keyframes for the layer/shape animations and, this way, the keyframes for the actual Mainline animation only need to be on the bone layer, along with all the rest of your character animation.

When tilting the head up and down, try using only y-movements. Any x-movements on the same layer or points can conflict with the head turns. To avoid problems, I might use only layer animation for tilts, and point animations for turns, or vice versa. Another trick to avoid conflicting motion is to use nested groups with different axis animation for each group.

Another trick that works well is to bind certain features to face bones, so you can 'slide' the facial features in the Bones layer instead of transforming the artwork layers. For example, create a Face bone parented to the Head bone, and then bind the facial features to this bone. You will also want to parent your 'iris' bones to the head bone, so the eyes move with the other facial features, even as you animate the 'iris' bones independently.

Sometimes, I may break down this hierarchy farther by adding a Mouth, Nose and Eyes bones parented to the Face bone. This way, for example, I can move or stretch the mouth Switch group in the bones layer and never touch the actual mouth group itself. With independent bones for different face parts, it's easy to achieve credible 3D-like movements in the head this way.

For some face bones, I may wish to have them controlled only by the SBD, so I'll use the Shy Bone option to hide them from the animator. If the animator really needs the animate these bones, he can use the Shy Bone command to toggle the visibility of these 'hidden' bones. Then, after he's done animating these bones, he can Shy them again to clear the clutter.

Hope this helps.
Last edited by Greenlaw on Mon Dec 04, 2017 8:08 am, edited 2 times in total.
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Greenlaw
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Re: Bone and X/Y scaling problem.

Post by Greenlaw »

For scaling, I like to transform a group directly. No need to use bones for this. You can nest multiple groups, each with its own origin if you wish to scale or rotate the contained art from different points. Moho can let you control independent X/Y scaling/rotations of these groups inside Smart Bone actions.

That doesn't mean you shouldn't use bones to transform layers--it's actually a valid and useful technique. But from what I'm seeing in the examples, I think this approach may be creating more work to animate this character than necessary.
Kiiryu
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Re: Bone and X/Y scaling problem.

Post by Kiiryu »

Thanks for the replies,

Long story short, look into smart bones. First thing's first, I'll take a look at a tutorial, and then if it turns out there's problem with that method, I'll take another look at your posts, abeit knowing how smart bones work.

Thanks for the help.
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