I'm worried I worked myself into a corner in regards to shoulder rigging

I’m not entirely sure how I’m supposed to weight paint this thing to make it look right. I’m worried that I may have to redo the skeleton or, worse, the mesh.

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hey hey, don’t worry be happy)
you have a good model so lets make something)
here is shot solution: un-attache vertex where I wrote “clear” - it may help.
IN any case the main rule is (not the clear but effective) - if you in trouble with joints - ADD another loop there (e.est add more vertexes there) for example add loops where green dotted lines i wrote.
maybe it helps)

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Well… I am always updating both, so maybe I shouldn’t reply here… but…

For one thing, you have a huge advantage because there is no right way for your character to deform. You get some slack that someone trying to emulate a human shoulder wouldn’t.

This was a very valuable resource for me: http://hippydrome.com

And here is his suggested weight painting:



He uses a very simple setup: Collar bone, bicep, and forearm. That’s it…

I tried clearing the weights ne_mo suggested. The ones around the shoulder only moved right, when what I really need them to do is move up.

I wasn’t actually making the collar bone deform anything, since I didn’t intend to animate it. I was just going to have the upper arm and the rib cage bones affecting the weights. Maybe I should weight and animate the collar bone though.

I’ve also attached what the weighting for the rib cage bone looks like.

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so you don’t want the little hump in the upper arm? From the looks of it you modeled it in to your arm (the left arm is the non-posed arm, right? That’s how you modeled it?). Try removing the weights for those bones, move the shoulder joint in closer to the center of your character, then weight painting.

Also look @ the arms from the front view. See how the chest kind of angles out towards the shoulders until it gets to just below the neck line & then does a sharp turn towards the arm? Try making that more gradual.

Well, even if you aren’t moving the collar bone, you might need it to hold the existing shape as the shoulder rotates.

It’s hard to say without looking at the Blend file, and seeing what you are trying to do…

So, using the rib cage bone wouldn’t be enough?
I guess I’ll weight the collar bone to see what that does in any case.

I’d attach my blend file but it is 1.2 MB, which apparently exceeds the attachment size limit. I also can’t attach a zip file.

It can be, if you add all of the vertices to it… but it probably makes more sense to attach it to the collar bone. Sometimes, you will want to move the collar bone, and you will want the mesh to move with it. (For a shoulder shrug, for example. )

OK, that’s weird. Unless you have a lot more in the scene, your blend file shouldn’t be that big… But, it’s OK. I don’t need to see it… it’s just sometimes things are easier to determine with the actual blend file in front of you…

Hm. Well, I’ve decided to put my blend file up on FileSmelt to get around the attachment size limit.

http://filesmelt.com/dl/zard.blend

Hopefully this will make it easier for you to help me out. Maybe you can also figure out why the file size is this big.

I guess it’s the textures that are giving you the file size…

You had a bunch of extraneous deformations in here. Something I am seeing a lot. Seems when you un-parent and re-parent a mesh, Blender sometimes keeps both.

I deleted all of those, as well as a host of extra vertex groups.

As for the rotation… Not sure what you want, so I’m not sure what to do. I reworked it a little, but if you want a smooth “gumby-like” bend, I think you’re going to need more bones in the joint. If you look at the FeelGoodComic rig in my shoulder thread, you can see what he does to get the shoulder moving. (http://blenderartists.org/forum/showthread.php?t=178120)

The other alternative – and what I find easier - is to correct the deformation with a shapekey. Then you either create a driver for the shape key so it brings itself into the mix whenever the bone is rotated, or you manually key the shapes along with your rotations.

Anyway… I put the small changes I made here:

Zard 3 If you want to look at it…

Thanks. What do you mean by “extraneous deformations” though?

If it helps, I’ll say that I didn’t actually parent the mesh to the skeleton and use any automatic weights. I simply created the armature modifier then manually painted some initial weights.

Yes, I do want a smooth “gumby” bend, but kept getting that dent on top of the shoulder. It’s as though the upper arm stays curved instead of straightening out. I guess what I’ll have to do is split the upper arm bone in two so that I can force the upper arm to be straight.

I looked through your shoulder thread. While some of the stuff seems a bit advanced for me, I noticed that a b-bone is placed between the collar bone and the upper arm bone a lot. Perhaps this is something I could try.

Also, for future reference, is it better to model the arms angled down like I have or to model them in a T-pose? While the T-pose seems to be more common, I’ve heard that modelling the arms angled down could lead to better results.

MisterMan,

After the stoopidd post I made last night, I’m hestiant to offer advice…but here it is…

I reworked the topology of the mesh on the left side a bit. I selected edge loops with Alt+RMB, used the Ctrl+E menu, and selected ‘Edge Slide’ and slide the edges around a bit. The attached pic shows in blue what edges I moved, and in red are other ones I would move.

I relaxed the weight painting on the ribcage bone, weight painted the clavicle bone, and relaxed the weight painting on the upperarm bone. You can vary the amounts of weight painting thru the ‘Paint’ panel in weight painting mode, adding, subtracting, mixing, etc. You can control the amounts and the size of the brush… a strong amount of control is available to you there…

Hope this helps…

Randy

I only did the left side of the mesh, and could refine it a bit further…but it’s not my project. Sorry…

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zard-2.blend (312 KB)

In the blend file, when you look at the object’s modifiers, there were more than one armature. This happens sometimes when you are working and reworking something. Nothing you did deliberately, or anything… but it is a residue that happens, so you have to be careful of it.

Well, there are a few ways of accomplishing it. Seriously, you ought to consider shape keys… it’s pretty simple to do.

You should model the arm in the more common pose – typically that is arm down. Actually, putting the arm in the pose you are talking about – straight out – is a fairly uncommon occurrence in most animations.

Arms usually swing front and back. Not straight up to the side…

Anyway, I’ve worked some more on the shoulder. Turns out that rigging the collar bone leads to relatively improved deformations. I’m still getting the shoulder dent when just moving the arm though. Maybe shape keys are the only way.

I did create and delete several armature modifiers when learning how they worked. How did you find the extra armatures?

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Looking good I think!

Select the mesh in the object mode. Click on the deformations panel (looks like a small wrench). They were listed there. But, to be honest,before I did that I did an unparent and reparent – so maybe I even created one? Not sure. The blend file I sent back had them all gone, though.

Also, make sure you check the vertex group (looks like a V shaped dot patten). Sometimes vertex groups hang around too, when you are adding and deleting things… parenting and unparenting…