ART tool can't adjust skeleton and keep weights

hi there,

I got a strange problem with the ART tool, which currently really hinders my progress unfortunately

I have a mesh which I created a skeleton for… a few hours into painting the skin weights I realized that I’d really like to move one of the bones, because I just can’t get a good deformation with the current placement.
when I go back to skeleton placement everything works fine, but when I return to deformation setup I get the following error after trying to import the previously painted skin weights:

"problems occurred with dependency graph setup. Aborting operation. please correct naming conflict and try again:

so my painted weights are lost;
but not only that, when I click on a mesh and on the paint tool I get the following error in the script editor

Error: TypeError: file C:/Users/xyz/Documents/maya/scripts/MayaTools/General/Scripts\ line 19559: argument of type ‘NoneType’ is not iterable

and some of the meshes are not even bound anymore

“Mesh has no skinCluster assigned.”

would anyone happen to know what I can do about that?

none of my meshes are just named ‘head’ or something like that by the way.

thanks a lot in advance,

a little update on that:

I updated to the latest version of the ART tool. it did fix a little problem I had with non-resizable windows in maya 2015/windows 8.1, but now I can’t go back to skeleton adjustment at all.
I get the following error message:

Error: IOError: file C:/Users/xyz/Documents/maya/scripts/MayaTools/General/Scripts\ line 10874: 2


as far as i know maya 2015 is not jet completely supported.

Also I encountered similar problems when using heat map skinning and/or had non-manifold geometry (the plugin telling me that no skinClusster is assigned even though there is and I can use the maya tools to weightpaint).

Im not from epic so these are just thoughts what could be the problem, I dont know any fixes.

Maybe exporting the skin weights by hand and reimporting them the same way once youre done adjusting your skeleton?

Hey Chris!

Sorry for the delay, I just got back from Holiday break.

One thing that would help a lot if is you can post the stack trace of the error, which you can turn on in the script editor history menu. It just helps track down where the problem originated.

From what I can tell though, it is erroring out when it is trying to cache your weights to disk.
line 10865: path = self.mayaToolsDir + “\General\ART\system\” + geo + “.txt”

it’s failing to find the above path, meaning either the geometry name is something that is not compatible with path names or your system folder doesn’t exist. Check to make sure you have the MayaTools\General\ART\system folder.

Hopefully, that’s the issue.

hey jeremy !
thanks a lot for getting back to me.
man, I have to say that’s a pretty impressive tool you wrote there! thanks for offering it to the community.

I just started learning rigging a short while ago, and I didn’t really what’s going on… like… generally speaking. I think the tool is definitely not for total beginners lol.
having said that:
now I got a better idea of the whole process and the tool is definitely a great time saver!
I did some testing in maya 2015 and on 2014/linux and it’s like said, it’s not really working in 2015; and on linux it shows (understandably) the same problems as on osx. however, it is working fine in maya 2014 + win.

I did want to ask you a quick question, though.

I did use the tool to create my character rig and then at the end I published the whole thing.
I opened up (and here is the problem) A file (I think it was the anim file) and kept working on that.
it’s the file with the sweeeet IK/FK rig + controls.

the problem is when I noticed bad stretching here and there which I hadn’t seen before, and I adjusted the skin weights some more, kept saving over it…
also I would like to move some joints just a few millimeters to get better deformation…

ok so the problem is that now when I open the file it says ‘no character found’, and if I try to run the ART it just starts from the very beginning, skeleton placement.
I could go to ‘edit character’ and load in my character, but I would basically lose all the changes I made to the ‘anim file’ in the meantime.
so my questions are:

  1. is there a way to tell the scene that my mesh in there is the ‘character’ so that it’s recognized correctly by ART?

  2. there doesnt seem to be any way to adjust joint position after the rig controls are created, is that correct?
    I went into the hypergraph and temporarily disconnected some of the constraints/drivers to move my joints, but as soon as I re-connect my geometry ends up somewhere else.
    theoretically I could just disconnect the whole rig and edit the skeleton, but then there’s no way to get the neat IK rig back without doing it manually all over again, is that correct?

would you happen to know how I could approach that?

I know that might be a bit of a weird question and unfortunately I seem to have broken the tool pipeline after publishing, so I’m just wondering if there’s a painless solution to this :slight_smile:

thanks a lot in advance and happy new year! better late than never :wink:


hello! :slight_smile:
yes, you’re totally right; it’s not working properly in 2015; I tested some more in 2014 and that was fine.
thanks for replying!

Hey Chris!

Thanks for the kind words. I’m glad you’re finding it somewhat useful!
It’s my bad for probably not laying out the workflow as good as I could have. The concept is basically, the tool creates two files, an export file, and a rig file. The export file houses your mesh, bones, and skin weights. The rig file uses that file to build the rig on top of.

So, you open your rig file and you notice some deformation issues that maybe you want to address right then and there. The idea was that all deformation and placement changes are done in your export file (the edit character option), and if those changes involved moving joints, you would then rebuild the rig file. If you’ve done weighting changes in your rig file, fret not! We can save those out! If you open the rig file for the character (using edit existing character->edit rig file), your bones should still be named correctly (no namespace). If so, you can export out your skin weights here so that we can load them back into the export file :slight_smile: Under Epic Games menu, go to Projects->Misc Tools and choose export skin weights. Then back in your export file, choose import skin weights and bring them back on, make your joint position adjustments, and rebuild!

Sorry for not having that clearer. Let me know if that works out for you!

hey jeremy!
you rock man, thank you very much!
actually I broke the mesh up into two objects in the rig file (just couldn’t get good skin weights with two overlapping meshes which I had previously combined) and then fixed up the skin weights information…
that’s why I thought ‘How am I going to get this back into the export file’
I thought skin weights are based on vertex number, kinda like blendshapes;

thanks for pointing out that they’re based on bones;
that’s great news, because like you said the bones have the same names in the export file.
so in theory I should be able to just separate the mesh out into the same two pieces in the export file, re-bind the skeleton and then import the previously exported weight files… and then re-build the rig.
I’ll try that first thing when I get home.

thanks a lot, really appreciate it that you took the time to reply so in-depth :slight_smile:


hmm… somehow my reply has disappeared :slight_smile:
anyway, just wanted to say thank you very much and I’m sure that solved the problem; I’ll check it out first thing when I get home.