mirror weight-painting and rigging a tube with constraint?

Hey there

I’m working on rigging a character, and this is the first time I’ve really used weight-painting. That part is working fine, but I had to paint each finger and each hand separately–is there a way to copy/paste or mirror the weight painting? it doesn’t seem likely to me since you have to click on the specific bone before painting it’s vertex group’s weight-map or whatever you call it.

Secondly, I want to rig a tube attached from the character’s jet-pack to the back of the left arm, so that it will bend on its own when I move the arm. I figured I could do a simple string of bones for the tube and then just constrain the end bone to the arm bone. But it doesn’t seem to be that easy. Any help or ideas on how to do that?

Here’s a video to give you some visual:


The weight paint tool itself has an x-mirror button which will mirror the painting across the X axis so long as:

  • The character is aligned along the X-axis (numpad 1 should be the front view of the character)
  • The mesh is symmetrical
  • The bones are named identically with ‘L/R’ suffixes

If you forgot to turn it on you can mirror the weights from one side to the other using this script.

As for the hose, hopefully the simple B-Bone IK chain based example I’ve attached will be sufficient :slight_smile:


hose_follow.blend (180 KB)

Thanks so much! Blenderartists is great =]

The tube works great so far…your example really helped. What’s the deal with the curved b-bones? Is there a purpose to that? I wasn’t able to replicate that in my file.

B-Bones can help ‘feather’ a deformation easier. Rather than having 4 or 5 bones that really don’t need to be manipulated individually, B-bones ‘subdivide’ one bone.

To get it in your file - goto 'Armature Bones > Segm > Add a few numbers to that.

I really don’t know why your IK constraint isn’t working though.

My IK constraint is working fine, I just didn’t know that was the one I needed =P

Thanks for the tip! Got the b-bones working too. (btw in 2.5 it’s in the Bone tab, inside the Deform drop-down.) Pretty cool feature.

Hmm sorry to bump this but the IK constraint is causing a problem.

With it activated, it screws around with the whole armature and makes it impossible to animate. Without it activated, everything works as I would expect (the only problem being, of course, that I’m back where I started).

Here’s the screencast to show you what’s happening:

It looks like you just need to set your chain length in the IK constraint to something other than 0. 0 means infinite, so it is effecting beyond the tube and into the rest of the rig.

Haha wow thanks. Glad you know all these little things.
I was just gonna get rid of the tube altogether…now I can start doing some animation tests. =]