A few comments about the rest...
Hoptoad wrote: ↑Sun Jun 20, 2021 4:48 am
Note that the arm in the above picture is in a Bone Group layer by itself; it is not affiliated with the Bone Group layer containing the torso and neck. They are two different puppets for a reason.
I made these puppets as a learning exercise involving exporting actions and importing actions. This is my objective: I want to create a library of arms where each arm is a micro-puppet that has been constructed with a Smart Bone Action to bend at the elbow...
To me, this sounds like a complicated animation workflow because the bones animation will have to be done in multiple layers. Trust me, it's easier to animate a character when all of its bones are in a single Bones layer.
IMO, the way you can do this is to copy and paste the arm bones into the Person Bones layer. Then you can use Copy Layer/Paste Layer to move the arm artwork into the Person group. (If you're arm has multiple layers, you should have it inside an arm group. This way, you only need to select and CL/PL the group, not every layer inside the group.) When you do this, the Smart Bone Actions will also copy into the Person group.
I looked at what's going on inside your arm setup, and here are some tips:
1. Use Linear keys inside a Smart Bone Action. If you use Smooth keys inside an SBA, that might not animate smoothly on the Mainline. Also, if you have multiple animations occurring in the SBA, using Linear keys will keep them in sync more easily and predictably. Keys inside an Action don't have to be set to Linear, but it's usually a good idea. (FWIW, it's what I use inside an SBA 99.9% of the time.)
2. Making a key at frame 1 inside the SBA is a good idea. Set this key as Linear but set the key at frame 0 to Smooth (or whichever mode you wish to be the default mode for the Mainline.)
3. If you haven't already done so, set the default Interpolation mode to Copy Previous Key.
4. I wouldn't bother setting angle constraint on limbs because you're restricting the posing possibilities of the character this way. FWIW, I almost never use angle constraints on a character's skeleton--I think these limits will make it it difficult hit strong key poses for the character.
5. If you rig the limbs properly, you shouldn't have to animate very many points inside an SBA to correct deformation. Normally, I'm only correcting two points inside the elbow. To see an example, look at the arm joint example I posted here:
Elbow Joint Example. This setup only takes only a few minutes to do with minimal editing.
One more question. Is there a way to copy and flip a left arm with a SBA, so that it can be used as a puppet's right arm with a pre-configured SBA? That would cut my SBA-time in half.
What I usually do is I save a copy of the character, then strip out everything but the limb and the bone it's parented to. Then I change the names of the bones and the relevant Actions. finally, I flip the root bone. Now we have the mirrored version of the arm with unique bones and action names, which can be inserted in the character without conflicts.
BTW, the reason you want to keep the root bone...without it, it's possible to break the Smart Bone Action. (I'd have to intentionally break one to remember and explain what I mean. Maybe if I have time later.)
Regarding the modular approach, I've created some modular setups at work for complex 'sub-rigs' like my hands setups that have a lot of SB controls, but it can be tricky. Sometimes I'll 'Frankenstein' characters from the parts of other characters but most of the time the characters I'm asked to build are so uniquely designed (meaning, very different from each other,) that I find it easier to just build them from scratch.
I'm hoping that some day we'll get a native system for designing and building modular rig parts but that doesn't really exist at this time.
All that said, please don't let anything I've written above discourage you from trying. I know what I've described is not as easy as what you're looking for, but don't give up trying to find an easier way to make a modular character setup. My comments are based on my experience but there are endless ways to work with Moho, and I'm always open to hearing about new/better ways to do something in the program.
Hope this helps.
