Adding facial bones to existing body armature without changing all weight paint

Hello
Please help, i have a makehuman rigged model, the body armature works fine.So i added facial rig bones mouths,eyebrows,etc.I added facial rig by the ""add single bones menu " in edit mode.Once the facial bones setup ready,i
entered parenting mode. The parenting works fine, the new facial bones are nicely deforming the face of the model, the big problem is that all of the rest of the bones weight paint have been slightly modified so the body bones deformations
are a bit (or totally for perfectionnists) broken, so i will need to tweak all the weight paints to get the basic nice working deformation.So My question is how to add new bones to an existing armature then parenting them to the mesh without modifying all the existing bones deformation.
Thanks

Did you do automatic weighting when you added the facial bones? I’m trying to understand how you got into this mess. :slight_smile:

The easiest way to avoid Re-Weight Painting is to not redo any Ctrl-P > use automajic weights proceedure that you have already performed on your mesh…
instead you can simply add extra bones into your armature (for what ever reason) then simply go to the Mesh and under the ‘mesh data’ properties menu (the triangle icon) just create a new vertex groups… name these new vertex groups the same as your newly created bones… you will then have to weight paint or weight assign vertices to those vertex groups (as they will be un-asigned to any vertices when you create them this way) but all your previous vertex groups will be untouched…

the problem is that i added at least 40 bones for the facial expressions so painting weight one by one is pretty hard.The initial model was rigged from makehuman with nice deformations (the blender skinning process is not very good for the model) but I’ve found that the blender’s automatic weight option is very good for facial rigging, i can get nice deformations.I’m lost…

I could be wrong because I’m not an expert of rigging, but I would proceed this way:
After you have your separate armature properly assigned to the figure, I would lock all the related vertex groups, and then add the 40 bones to the original armature (as children of the head, I guess).
After that you should be able to normalize the head vertex group without affecting the weights of the new added bones.

paolo

Sourvinos>>>if locking vertex group means clicking on the locker small icon near to the vertex group name, i 've already tried but didn’t work, did i miss something or it’s not the proper way to do it? Anyway i’ve found an another solution

  1. from the initial rigged model i selected the head then separated it to the body (edit mode>press P) ,
  2. then parent the armature with auto weight option to the head mesh
    3.now the facial bones are working nicely, rejoin the head and the body mesh by Ctrl+J
    4.entering edit mode them merge the vertex one by one (alt+M>center) pretty easy because the vertex are already aligned with same number , no more tweaking needed
    5.Now You have a nicely deformed speaking character.

If you have an another solution i’m open :slight_smile:

No other solutions apart from what formerly proposed, the lock icon on the right in vertex group list always worked for me.
Your solution cannot be the right one in general, because it can break many things, first of all shape keys.
But if it worked for you, good.
BTW, to rejoin the meshes you can simply select the border loops and remove doubles.

paolo

@ sourvinos I’m intregued…

I could be wrong because I’m not an expert of rigging, but I would proceed this way:
After you have your separate armature properly assigned to the figure, I would lock all the related vertex groups, and then add the 40 bones to the original armature (as children of the head, I guess).
After that you should be able to normalize the head vertex group without affecting the weights of the new added bones.

your saying… and bear with me so I’m making sure I get this strait… (cause this is news to me)… that I can go hit the “lock all” button in the pull down bar (under the down arrow key) in the vertex groups … to lock all the vertex groups and that will effectively lock off the weight painting that has been done on them… (or the autoweighting or what ever) such that … now I could go into the Armature and add and delete bones and then use something like the “W > assign automatic from bones” and it should protect all the other vertex weights…

norvman,
I think yes, not sure about assign automatic, but it should at least permit the adding and painting of new bones without affecting the old groups, and unlocking just the proper groups, to allow normalizing of the wanted bones only.

paolo

thanks for the share on this… I have spent the past few hours messing with this and it works great!..

I’m glad it works!

paolo