How to skin characters with lots of overlapping stuff and complex surface structures?

rollin

Hey I looked into our Wiki regarding this (btw @Eric Chadwick  I think it's not ideal to mix it into the Rigging topic as it deserves it's own spot imo)

But I'm wondering if there is any new or updated tips and tricks (also focused towards blender a bit) how this can be done in the most efficient and practical way. 

For now I think this is my best bet but I don't have a lot of experience with those complex topology structures and not much knowledge about new technology used in films and vfx for these cases.

Cheers!

carvuliero

Do you have reference of what you want to skin ?

In general you will skin and paint weights on the bottom most layer nude body if you have one and work your way up transferring weight to the cloths[if they are form fitting and have similar topology is pretty simple ] and fixing artefacts and collapsing geometry

Eric Chadwick

About the wiki, I'm cool with you adding another section. PM me and I'll get you setup as a wiki editor, it's pretty easy to learn.

rollin

@carvuliero

For example the cyberpunk chars
https://3images.cgames.de/images/gamestar/287/cyberpunk-2077-gangs_6113512.jpg

There you have layered stuff and also rigid pieces like metal braces which should ideally not deform in itself.
Of course you can go the manual way but this becomes very time consuming.

FourtyNights

This is also something I've been trying to figure out, since my character projects also consist from multiple separate meshes, instead of a fused watertight low poly (which is more an old workflow from early 2000s).

Arrimus 3D explains how simple proxy mesh can deform multiple complex meshes. Weights can also be transferred to the complex meshes once the deformation is working with the proxy mesh, and the target mesh. It's for 3ds Max, but I think it can be done in Blender too. It's something I'm trying to figure out as a workflow at some point, but don't know how, yet.

https://www.youtube.com/watch?v=hDXp03Cvie8

But if you wish to to deform individual more or less rigid meshes, which correct the certain pose of a character, you'll need more control bones/joints. For example with pouches moving with physics and gravity, or when a character moves its upper leg towards its chest, an edge of a shirt, jacket or armor moves away to avoid clipping. Something to do with bones driving other bones with constraints and so on. For this kind of workflow, I don't know any artist-friendly way, and I'm not a professional rigger either. I'm just a character artist learning rigging.

But I think proxy mesh skinning is at least making something easier. Hope this helps.

Ghogiel

So you are wanting to skin layered things without much tedium in a non best case scenario automagically? So does everyone else XD.

If the topology decently thought out, and it'll have to be to make the skinning less problemmatic, like loops and verts on all the layered bits matching up, at least roughly, I'd guess some voxel skinning would get you a good start. For overlapping bits there are skin wrapping/copying tools that can transfer weights about.  There are probably ways to take a main reference well weighted humanoid model and use the weights on that  on everything else so everything is very close if there is some modularity with meshes. Then the ol manual cleanup. You might find there are bones for some hard parts on characters, like shoulder pad bones or something, but you might also find some clipping or blend weights on things that you would normally not deform and be rigid, like hard plates on arms.

carvuliero

rollin said:

There you have layered stuff and also rigid pieces like metal braces which should ideally not deform in itself.

Of course you can go the manual way but this becomes very time consuming.

Yes thats the ideal case but unfortunately if rigid object is close to a joint it has to bend I am sure you have seen plenty of games where

metal armor stretch like a rubber especially around the shoulders

I have to repeat myself about possible workflow for rigging this type of character or any other 

If there is a base mesh [nude body] you bind that to the skeleton and paint the best weight you can if there is no such base mesh

you got the first layer of clothing and do the same step .Once you have good weight you can start binding one by one  second layer of cloths and accessories transferring weights from bottom to top layer ,fixing any possible issues if there are any .This is your workflow for "glue on" objects like bags belts straps jacket and so on if object has individual control and extra joint you have to paint custom weight

Thats pretty much is not that different from binding a plain 1 layer character its just more time consuming and prone to issues and artefacts

due to not compatible topology between layers

To recap you paint weights once on the most bottom layer transfer to top layers [working smart not hard right] fixing any problem[usually weight transfer on thick pieces is not perfect ] and finally custom pieces [if some belt or bag has to bounce or follow through]

DavidCruz

For not using blender i at least have (i think) somewhat helpful mentions if nothing else:
This
https://www.youtube.com/watch?v=HSp3fNDzb74 check latest videos on it, seems very handy.

Might be what you want since it seems straight forward but you have to dish out a bit of cash for it, which in the grand skeem(is this not a word?) of things seems minuscule to the amount of work one has to do for multiple characters.
Hope it helps.

pior

"For example the cyberpunk chars
https://3images.cgames.de/images/gamestar/287/cyberpunk-2077-gangs_6113512.jpg"

Well ... what precisely do you think would cause problems there ? Most everything on these characters would probably behave nicely by simply transferring the weights directly from a base naked body and smoothing a few places here and there. Just because a leather strap sits "on top" of a pair of paints doesn't mean that it isn't welded to it on the actual model.

Also, anything (or rather, nothing) can be assumed about the behavior of these models from a static image. What do these characters look like in motion ?

Also, do you have a practical model that you are testing these things with ?