Difficult problems in skinning

#1

It’s easy to skin each seperate bone,but put several bones together it will be very hard to get it right,
take DAZ’s Victoria8 for example,the following image shows the result of moving the bone “lowerFaceRig”,

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In the image as I pointed out,some parts become bumpy,although it’s smooth when move each child bone which has no children,but to move the parent bone “lowerFaceRig” the mesh becomes bumpy,I believe it’s possible to adjust each bone weight of each vertex to solve the problem,but because of the interaction of different bones,change one weight will mess up others,so the adjust may end up in an infinite cycle,think about rigging a character with 50 facial bones properly(in my opinion the DAZ one isn’t proper) will be a nightmare,so is there any tool or method to simplify the work?

#2

Rigging a face with bones is a very tedious subject in most software, It’s not clear what you were trying to accomplish with this screenshot. Provide bones setup, what you were to create. Right now it’s something beyond a scope of what a human can do with its muscles in real life.
Several bones would have a limited overlapping effect in this scenario. Also you should have a jaw bone to move it, so facial bones would create more subtle nuances.
Maybe it’s possiblre with autorig in Houdini, but anyway it’s not an easy endeavour.

#3

I will give another try to explain the requirement,this image shows the moving of outer brow,mid brow,inner brow,center brow by exactly the same distance,

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you can see the edges deformed become bumpy,my ruquirement is to make these edges keep even and smooth after deformation,because base mesh’s edges is even and smooth,and all the brow bones move exactly the same distance.This can be accomplished by refine bone weights,but how? say to refine outter brow first,make edges even and smooth after moving outter brow,then proceed to the neighbour bone mid brow, again make edges even and smooth after moving mid brow,but you may find you have to refine outter brow again,because change weight of mid bone will change weight of outter bone at the same time,and in many parts there will be 4 or more bones interact each other,the refine will end up in extremely long cycle,so I think some tools or methods are quite necessary,but is there any?

#4

If it’s a basic setup, then bones should have separate areas of skinning, i.e not having 3 bones affecting the same vertices. So first you make a rough blocking of skinning, with 100% weights. And then, depending on finessing, you create blended vetices, sometimes adjusting each vertex weights, entering weights ratio between two bones. You’d want 2 bones having an adjacent effect simply for soft tissue effect, not 3 or more.
Even with blendshapes (morph targets) you want to isolate those affections, otherwise you will get those unwanted interlinks.
And if you want to create bones, which affect adjacent bones (not via skinning, but via bones setup), that’s what you probably want, but it’s tricky to setup. By that I mean you move one bone, it moves two adjacent slightly.
It depends, of course, on how bones are implemented in a particular software. If they have a robust stretch setup, it might be easier. But once again, you don’t want to create this effect with skinning solely.
You could create parent objects for groups of those bones, for example one for 3 brow bones to move them all. It’s a simpler setup, but not as easy to animate. Then some connecting to the lower jaw.
Creating stretchy interconnected bones is not easy to setup. If you can get by with blendshapes, go for it.

#5

Start with blocking skinning then refine to soft tissue effect,but the refine is extremely tricky,because in my case it’s impossible to limit overlapped bones to 2,most of the time there will be 4 or more,I think the effort needed is unaffordable,so I want to find some tools to save my life.If what I want is only an acceptable result,like daz victoria8,it’s possible with some reasonable work,but I want to be nearly perfect.
As of adjacent bones, I don’t think it will solve the problem.blender shapes can get the desired result,but I want to have a nice skinng,becasue I will use this model as a template,I want it to be nealy perfect.
I googled a lot,seems no tool avaliable currently.Think about a vertex affected by 4 bones,for the best deformation,each of the 4 weights should be set to a specific value,but how to get these 4 values?the work needed maybe unaffordable for a 20000+ vertices character.