avatar_skeleton.xml (female system armature)

[AdaRadius]

What I've been doing with the avatar_skeleton.xml to Blender armature conversion. This can be a useful armature to use for vertex weighting, as it replicates, as well as possible, the viewer system female armature in Blender.

• Corrected errors in Blender bone settings. "Inherit Scale" should be "none", but local and inherit rotation should be checked.
• Corrected bone group and layer assignments; more or less follow group structure in the xml file.
• Corrected bone and tail x,y,z positions. I thought that the version I uploaded earlier was the one built directly from avatar_skeleton.xml data, but I apparently had made an attempt at rebuilding the "broken" SLWiki bento download - at some point and some of those numbers were in there instead of the xml file data. Enough of a difference that I could see it in the Blender file, and it affects auto-vertex-weighting for the hand and face bones, where the thresholds are smaller. Dunno why SL provided an armature different than the system armature.
  NOTES:
• Whether or not bones are connected in the armature hierarchy is defined in avatar_skeleton.xml, but bone tail to subsequent bone head numbers don't always match. I copy-pasted from the xml file to Blender in hierarchy order, which is best effort I think. The mismatches are color coded in the spreadsheet.
• I did not replicate the avatar_skeleton.xml left-right symmetry errors; I input the left values and mirrored to the right, as the xml file usually (not always) lists the left bones before the right bones. I color coded the mismatches in the spreadsheet. The differences are probably not significant and Blender tools are easier to use with a symmetrical build.
• There are some inworld armature settings inworld we can't replicate in Blender, or at least not perfectly. The Appearance sliders for the system avatar inworld are driven by morphs (see avatar_lad.xml), but for attachments, such as mesh bodies and clothing, we have to define how the sliders will work with vertex weighting.
• When we export dae files from the Blender file, the rounding changes, as it does with dae imports. I don't know how Blender calculates them; how Blender handles dae importing and exporting is a subject of much complaint at some forums.

TO DO:
When I have time I'll add control bones and figure out better bone roll (now all set to zero) to make this a more useful tool.

[AdaRadius]

I replaced the armatures and spreadsheet - I changed my mind on the best ways to convert the viewer Character xml files from old Maya to current Blender.

• I unchecked "connected" in bone settings, so Blender wouldn't change the bone length on the bones where avatar_skeleton.xml has a head to tail mismatch. Doesn't seem to affect importing to the viewer with a mesh attachment
• There are two sets of parameters for the mBones - pivot and pos. I clarified that this armature uses the pivot numbers for the mBones. Only pos settings are available for the collision bones, which also need custom settings to work on exporting and importing. I included fairly ancient custom settings that work for now (Blender 2.92) but may not in future. I don't know enough Python right now to do needed upgrades, if they're needed.
• I did not correct the left to right asymmetries in avatar_skeleton.xml for this version.
• I removed the Blender conversion calculation sheets from the spreadsheet. I've revised them extensively and haven't tested the changes enough. I've changed my mind on the right way to this quite a few times, and that's just today. The very small number of people who are actually interested in working on this know how to contact me :)

Yes, I'm working on Blender versions that use the pos values for mBones, preparing to add armature morph values for Appearance > Female to Male, and the other armature morphs used in the Appearance sliders. See avatar_lad.xml. I think those versions will be cleaner for adding IK and other control bones for animating, but I haven't finished testing. A pos value version theoretically should be better for replicating the inworld armature, and to create a versions that could be used to convert the avatar_lad.xml morphs for the R3 project. I won't upload any of that here anytime soon. I wouldn't be able to field questions for what will be an experimental long term off-and-on project and for which I'll need a lot of programming help. C++ and Python.
:)