Body mesh twisting on intermediate weight settings

[AlpineYJ]

Hey there!

Long time listener, first time caller (Bob & Tom reference).

I made this recently: http://www.nexusmods.com/skyrim/mods/56463

Basically, all I did was form the lower parts of a UNP BBP mesh around a SeveNBase Bombshell body. It didn't take long, and it came out extremely well. A couple of days later, a helpful Nexus user pointed out that the offset of the body was off -vs- the hands, etc. I looked at it using the mod he was referencing, and sure enough - it's off.

Anyway, I had a fix done within a couple of hours, except that I used a TBBP body this time. TBBP bodies (in the past) have given me fits for some odd reason, and this one is no exception. The body shows up in-game and looks fantastic at either the 0 or 100 weight settings. When I move the weight slider in RaceMenu to *any* intermediate weight, the vertices twist and distort themselves really badly - almost looks like a transporter accident (think Star Trek I). When I move the slider all the way to the 0 or 100 side, the vertices "snap" back to position as if nothing was wrong.

I use Blender 2.49a, NifTools, etc, etc. I've converted gobs of armor meshes (non-bouncy) with no issues. The only oddities I run into are when I try to do something with TBBP bodies. I've made the modification within nif_common.py to change the max bones per partition from 18 to 60. Before that modification, the result was an exploded mess.

To summarize: non-bouncy bodies work fine, BBP bodies work fine, TBBP bodies melt at intermediate weights.

I am at work, so I can't post some melty nifs. I will be happy to do it when I get home if needed. If anybody happens to know off the top of their head what is wrong (or what could be wrong), I am open for ideas.

Thanks for any help anybody can give me!

Edited August 1, 2014 by AlpineYJ

[Hanaisse]

My guess would be the extra breast bones and weight painting in a TBBP body causing the issue. There are many vertices around the chest area and if they start to cross over because of the conversion from _0 to _1 weights, it would cause that explosion.

 

I haven't looked into these type of body meshes closely, but would Caliente's BodySlide / Outfit Studio help? (you'll have to look it up on Nexus, I can't link it here due to it's content)

[AlpineYJ]

I've used Bodyslide & Outfit Studio extensively.  I used CBBE for ages prior to digging into making a new body type.  I still use Outfit Studio to make minor armor adjustments after an initial conversion.  I don't think it would help me much with this particular issue.  :/

 

I gathered some more information that I am hoping will be helpful.  I made and uploaded a 7zip that contains the "before" meshes, "after" meshes, along with two videos.  One video shows my workflow for importing & exporting a mesh into and out of Blender, and the other shows the resulting mess using the RaceMenu body slider.  I used a pre-weighted TBBP UNP body for this demo.  All I did was import it into Blender, then export it again - no other adjustments.  There is obviously something I am missing - or there is a trick that I am missing.    As I've mentioned, I've used Blender to convert gobs of armors (for my own use), and this is the very first time I've encountered anything like this.

 

https://drive.google.com/file/d/0B2rUWJmi6w3DbVlKTVdNTG56ZzA/edit?usp=sharing

 

If the content in the archive is too much for the general viewing public, please let me know and I will pull the link.

[AlpineYJ]

Ok, I have this one fixed.

 

I ended up using the Mesh Rigger (will want to Google it, as it lives on a less than SFW site).  I selected one of the pre-imported meshes & copied all of the bones & weights over to the post-imported mesh.  It worked beautifully.    If anybody wants me to video a workflow for it, let me know.  It's pretty easy to use.