[X3D-Ecosystem] Does this AI program generally look correct?

[Joe D Williams]

> bone tail should not be child joint center.  

Of course it should.
A bone tail is the child of the bone head,
and the bone head is the same as the
parent joint of the bone.
The hierarchy is produced when a child bone tail
is the same as the parent Joint of a child bone head.
   
A bone is a typical connection device to make a skeleton.
The skeleton consists of a realistic set of bones
set in a realistic hierarchy designed to
reproduce human poses and motions. 
  
A bone has a head which is either the skeleton root 
or a child anchor location that allows setting
the bone orientation and thus the bone tail location 
by rotation of the x, y, and z axes pivot point
at the bone head. 
    
Since animation is produced by rotation of one or a
certain set of bone heads, we want to go ahead and
just call the head of a bone a Joint. 
Then, a Joint is connected to another Joint, or
an end-effector by a bone, which because
there may be other styles of attachment, 
we call a bone a Segment. 

While the viewer observes skeletal poses
as changes in bone position and orientation,
that motion is actually produced by the character
using equivalent rotation of an appropriate Joint. 

Thanks for the fun with HAnim, 
Joe

-----Original Message-----
From: John Carlson <yottzumm at gmail.com>
Sent: Jan 16, 2025 10:55 PM
To: X3D Ecosystem public discussion <x3d-ecosystem at web3d.org>, Katy Schildmeyer KS APPAREL DESIGN <katy at ksappareldesign.com>, Joe D Williams <joedwil at earthlink.net>, Michalis Kamburelis <michalis.kambi at gmail.com>, Vincent Marchetti <vmarchetti at kshell.com>, Carol McDonald <cemd2 at comcast.net>, GPU Group <gpugroup at gmail.com>
Subject: Re: Does this AI program generally look correct?

Here’s another option:
 
https://claude.site/artifacts/fa241e9b-1755-4ae6-8bcf-ea4841248b9a

What these two seem to indicate is that bone tail should not be child joint center.  What do you think?  Also, since it’s not only the bone head influencing the skin, perhaps we should change the length of the bones I’m loading?
 
I’m puzzled, because I see a difference in how Claude seems to indicate how bone influences the skin than what you guys have been telling me, but perhaps you guys assumed short bone length?
 
John 

On Fri, Jan 17, 2025 at 12:42 AM John Carlson <yottzumm at gmail.com (mailto:yottzumm at gmail.com)> wrote:
If we can agree that this generally looks ok, I will try to implement this in the Blender importer:  https://claude.site/artifacts/7c4c15f2-1bde-4da5-9503-f4f25b09016a
 
I realize the bone.tail should probably be the child joint center.
 
I do not yet know what i am doing wrong, but my focus will be shifting to animation import after export is done to my satisfaction.




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