mhx rig dfmhead and head

[phantomias]

Hi all,

I exported my makehuman avatar to blender (mhx) and from there to fbx. For animation I use Motionbuilder. So far everythings works fine. In Motionbuilder I want to set up the character. Therefor I have to connect the makehuman bones to the internal motionbuilder bone structure.

The problem now is the hierarchy. The bones head and dfmhead are both children of dfmneck. For Motionbuilder this is a problem, because it requires one bone for the head. Actual you have two bones (one for the upper head, one for jaw and face things).

To solve the problem in Motionbuilder you just need to change the hierarchy. Now the head is a child of dfmhead.

When I create new Avatars I don't want to change the structure everytime, so my question is, what is the best way for creating this behavior (hierarchy). I couldn't find a mhxrig file in the makehumanfolder and I don't want to create a new rig, because the mhx rig is fine.

Thanks in advance

[ThomasL]

Hm. Not so easy.

There is no rig file for the mhx rig; it is hard-coded in python and uses a lot of features not available in rig files. Once I did start to invent a more complete rig format and migrate the mhx rig there, but this project is put on hold at the moment.

The reason to parent Head to DfmNeck is that there are in fact two different control spines: the normal up spine that pivots around the pelvis, and the inverse down spine that pivots around the shoulder, useful e.g. for hand-walking. The spines end (or start) at the neck. Depending on a property, DfmNeck copies the rotation of either the up neck or the down neck. Head is a child of DfmNeck because we want it to always be on top of the active neck control.

One thing that could be done is to introduce an option to disable the inverse spine, and make Head the child of Neck. Contrary to what I thought when I started to write this post, I now think that it should be easy. Will look into it.

[phantomias]

Hi,

I saw similar problems at the legs. Maybe you can there also change the hierarchy?

[ThomasL]

A new export option was introduced a couple of days ago: Advanced Spine.

If true, there are two control spines and the limbs (Head, Clavicle_L/_R, Hip_L/R) attach to the deform spine to always be correctly positioned.

If false (the default), there is only a single control spine, and the limbs connect directly to it.

This should solve your problem. Export the character with Advanced Spine deselected and try again. I'm interesting in hearing if things work now.

[phantomias]

Hi,

I checked the new nightly builds and found the new option. Actual this still doesn't solve the problem. Now I've two skeletons/rigs in motionbuilder. One is the root and one is deformer pelvis. I put a screenshot of the results when rotating the head in motionbuilder

.

I suggest, that the dfm bones are children of the "real" bones e.g. (look at the hierarchy at the lower left)

Similar things I suggest for the legs

with option would be great.