Problem Fixing Weights

[t_smith5]

I'm currently trying to pose a low-poly character model. I've assigned all of the weights, but with a particular pose, I need to make a slight adjustment to the weights on the arm. When the arm bends at the elbow, I want to add a bit of a crease on the forearm.

However, if I decrease the amount of weights, this stupidity happens...

I'm not sure why or how to fix it. I can't help but think it's a bug. If the weight is currently at .75 and I set it to 0, it's fine. If I set it to 1 and *then* go to 0, that happens. Any ideas?

Thanks

[10DSpace · Accepted solution]

@t_smith5 

It looks like maybe you have "Normalize" unchecked and in messing around with the different weights of whatever bones are influencing the selected vertices, you are creating values that do not add to 1 or exceed 1.  See image below.   For your low poly  mesh there should only be 2 bones influencing the elbow vertices (Upper arm and lower arm) , so another issue could be that you have other bones with inappropriate weights on the elbow vertices.  But assuming you just have the Left Upper arm and Left forearm influencing the elbow vertices, make sure normalize is checked and then start with .5 for each bone and tweak from there to get the best result you can.  With such low poly geometry, you will only be able to take it so far.   

The Weight tool is very helpful in seeing what bones are affecting the selected vertices and if you open that and include it in your screenshot it will help anyone here diagnose your issue if the above does not solve it for you.

[t_smith5]

Thanks for the response and advice. I'll check the Normals now. After that, I'll see if the vertices are being affected by other bones and then report back. 🙂

[t_smith5]

So Normalise is checked, so that's not the issue, but it looks like the Spine bones are also affecting the Forearm. Not sure why or how that's happened. As well as just putting those to 0, is there no way of being able to delete them from the list? They keep being affected again and again even after putting them to 0. 😕

[10DSpace · Accepted solution]

@t_smith5 

As well as just putting those to 0, is there no way of being able to delete them from the list?

Yes, very easy to delete them from list once the weights are set to 0.  In the Advance Parameters tab of the Skin rollout click on the button "Remove Zero Weights".  It is good practice to do this so they don't bother you further while tweaking weights. 

[t_smith5]

Awesome! Thank you. 😄

[t_smith5]

I have noticed once they've been removed, that any bones that have vertices at 1, I can no longer reduce their weight.

[domo.spaji]

Isn't that normal and logical?

Normalized vert must have total weight = 1. You can't  reduce that.

But you can share that to multiple bones.

So assign part of that to other bone.

[t_smith5]

I just figured, like I've been able to with every other bone whilst Normalise has been enabled, that I can vary the amount of weight applied to a specific area.