Deformed Mesh.

[GManB]

Posted this in the Animesh forum and it was suggested that I cross post here.

----------------------------------------

I am trying to animate a star-shaped, very thin, mesh. Shhhh.. it's a present...

 

First, though, I was recently successful in re-arranging 62 joints of the default SL skeleton from the  fbx file here, http://wiki.secondlife.com/wiki/Project_Bento_Resources_and_Information,  into a long single line for a 13-meter snake and successfully imported it to SL and created an animation for it which worked as expected. So, I thought I understood, at least somewhat, how to carefully re-arrange the joints and make things work. 

I wanted to animate a piece of paper to fold itself into some pleasing shape, a self-creating Origami, if you will. After some animation experiments in Maya I ended up with a thin 10-point start. I used joints to the head, two arms, two wings, four legs, and the tail. Piled, mPelvis, mChest, mTorso, mWIngsRoot, mHindLegsRoot in the center with from joints from the each appendage radiating out toward the points. Pics below.

I think the problem is in the skin weights.. If I flood the mesh with a weight of 1.0 from mPelvis the shape uploads and rezzes properly in SL. Of course, this was just a test since I could not animate anything. When applying skin weights for each joint, both automatically with different options and manually, the upload is ok but when Animated Mesh is checked the resulting mesh is deformed.

Since the test with all verts given a weight of 1.0 on mPelvis resulted in a properly formed mesh my assumption is that the issue is with skin weights and not due to rearranging the joints and the resulting joint locations.

Things I had tried:

• Making it thick to potentially avoid the 'too thin mesh' issue. Doesn't seem to make a difference.
• Hand painting all the skin weights.
• Many different options to the automatic process for binding a mesh to joints available in Maya.
• Re re-arranging the joints into the same pattern but more closely aligned with skeleton.
• Using only the 40 joints of each point in the skinning process
• I am sure there have been others

 

Any ideas, suggestions, caveats, insights, or criticisms welcome.

 

Thanks,

G

 

P.S. One thing I noticed is that even in the test with a well-formed the joints don't seem to be in the proper place. This might lead one to think that joint location is an issue but note that with different distributions of skin weights I get differently deformed versions. This doesn't necessarily rule out joint position as a contributing factor but thought it worth mentioning. 

 

Mesh and joints in Maya

 

Test with all verts having a weight of 1.0 from mPelvis. Good shape.

 

Mangled versions:

Edited March 19, 2021 by GManB
Forgot explanation

[Pixels Sideways]

hi Gman:

You may find this three part tutorial (link below) on SL armature rigging in Blender helpful - it's a rather complex process that involves using various resources to fix the armature because of volume collision bones vs the m-bones and certain body templates missing stuff but it is very thorough and also provides resource links for the sl bodies/armatures and other files. 

I have run into the same deformation issues when importing a rigged body I had altered from a basic rigged sl body template in Blender.  We discovered this issue early on with animesh when we tried to shrink the SL avatar in Blender and import in SL then switch on the animesh feature.  The body deformed.  However, I had some all rigged mesh avatars i had found on MP (Dr. Who, Spock) which were imported with the standard rigging and they worked with animesh.  This is a test Artee and I did on the animesh sim.  I dropped an animation into the Dr. Who avatar then attached to my avatar center.   

You can see toward the end of the vid Artee's deformed avatar that was altered in Blender to be a small human basic avatar but got borked after importing into SL when Artee turned on the animesh feature.

 

In a perfect world, Linden Lab would make perfectly complete and properly rigged Bento male and female body templates / armatures available for Blender that could easily be altered and correctly imported into SL because Blender is free vs Maya which is subscription based at around $1600.year.  

I was going to mention you might be able to fix the issue using Avastar which is a SL add-on for Blender for rigging clothing, etc., but it seems there may be issues there regarding all of this as mentioned in the tutorial but it may be worth looking into.

 

Here is the link for the tutorials.

https://adaradius.com/2020/01/16/blender2-81-dae-export-part1/

Here is a link to Avastar:

https://blog.machinimatrix.org

 

Good luck.

Edited May 19, 2021 by Pixels Sideways