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Bone Heat weighting: failed
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Win 10 64. gtx 970

Blender 2.75a Hash c27589e

Bone Heat weighting: failed to find solution for one or more bones

I attach the blend file and two prints..

Also the same broblems apper when i try to "assign automatic from bones" by individual bones in Weight Paint. Like one by one. Please see print2.



Event Timeline

pistol ioan (pistoltoto) set Type to Bug.
pistol ioan (pistoltoto) created this task.
pistol ioan (pistoltoto) raised the priority of this task from to Needs Triage by Developer.
Bastien Montagne (mont29) triaged this task as Normal priority.

Not sure we’d consider that a bug, bone heating process is rather complex and not guaranteed to success afaik.

@Lukas Toenne (lukastoenne), @Sergey Sharybin (sergey), @Campbell Barton (campbellbarton), maybe you know more about it?

Is very nasty to paint every bone.
Please consider to solve this problem.


Bastien Montagne (mont29) renamed this task from Bone Hear weighting: failed to Bone Heat weighting: failed.Jul 19 2015, 3:47 PM

A workaround is to split the mesh and then bind the weights. Enter editmode on the mesh, L linked select the body, P to separate into a separate mesh, compute the weights for the two meshes separately, and Ctrl + J join them again.

It seems there is some issue with the teeth where they are not visible to any bone, which is somehow messing things up.

I think the problem is that the algorithm does not explicitly handle connected components separately. They are all handled in a single matrix, and that's usually fine. But if none of the vertices in a connected component are visible to any bones, then the matrix will not be invertible, and the solve will fail for all components.

The solution would be to detect such cases, and then disable visibility tests for such components, or somehow get the weights from nearby components. Switching the code to use BMesh instead of Mesh would make that easier.

Wow, the guy who created Cycles is still with us.
The cycles is the main reason why i love Bender.

You are awesome Brecht Van Lommel !!

As I wrote at the other report, that got merged to this one now:
Auto weights was a guaranteed process with 2.70 for humanoid characters, but it doesn't work at all since 2.75. And that is only with specifically Rigify generated rigs.
Most Rigify Video Tutorials including payed once are even mostly based on that process to distribute weights.

It's not just some bones failing but all of them.

gregus (gregus) added a comment.EditedApr 25 2017, 9:18 AM


I can't succeed in parenting a character to a rig with the "automatic weights" function. "Bone Heat Weighting: failed to find solution
for one or more bones" is always returned.
Character mesh seems okay, there are no separated parts and no non-manifolds vertex/edges.

  1. select the character
  2. select the rig
  3. CTRL +P with "automatic weights"



System Information
win 7 SP1, GTX 670M

Blender Version
Broken: 2.78a and 2.78.4{F572514}

Right now "automatic weights" just leaves you with an error message.

Suggestions :

  1. When the script has an issue in solving the assignation of a weightmap to a specific bone,it should leave this bone and jump to the next one so that the process can go on on the rest of the mesh which is correct.

Then, there can be an error message at the end of the process, but maybe 80-90 % of weightmaps are created and that's a big improvement.
The remaining "bad parts " can later be manually assigned.

  1. the parts of the mesh with poly/vertex problems should be shown selected so that we know WHERE is the problem.

Huh, this is interesting. I have tested both cat.blend and automatic weights.blend and it seems that I was able to successfully use automatic weights by simply scaling models up about three times. For example, I can open automatic weights.blend, scale the model to its natural height of 1.65 m (2.5 scale), apply the scale, scale the Armature in Edit Mode to the same size (I used 3D Cursor as a base for scaling), Ctrl+P - Automatic Weight and after a while it successfully did what it supposed to. Cat.blend is harder to work with but if I scale the Armature about 3 times it seems to be working as well; there are still problems with very small details but weights were assigned without errors. All in all, it looks like there is a problem with small sizes and precision and scaling to bigger size worked for both cases.

You can also consider acquire this plug-in and use atop of blender automatic weight painting:

It saved me a lot of trouble.