[x3d-public] FW: BVH to X3D Conversion bug

[Joseph D Williams]

Brought out to public

From: Joseph D Williams
Sent: Friday, October 28, 2022 5:49 PM
To: John Carlson; Norbraten, Terry (CIV); X3D Graphics public mailing list
Cc: Brutzman, Donald (Don) (CIV)
Subject: RE: BVH to X3D Conversion bug

➢ The Pirouette.x3d has
➢ <component level='1' name='HAnim’/>

An error.
Hanim has basically two levels – 
skeleton with segment geometry and 
skeleton with skin. 
Check me on this. 
However the piro example is Not Level 1, or any level because the skeleton is Not a legal level of articulation. 
This skeleton may be typical in bvh archives because it is a legacy artifact from before we had a world standard realistic skeleton. Just look at it. Is that the way your back works? But, it is simple for simple stuffs.

If you play with this loa non-conformer, like for instance hook the animation up to any of the more or less standard and proven stand walk run jump twist etc. animations in the archive, then I am fairly sure you will see unexpected gestures. And, when one or some of these work in a ‘standard’ hierarchy skeleton, then add it to the “Standard” examples. 

Certainly, as you progress with authored hanim animation style, then you will wish you had started with current vs legacy skeleton, same as possible regret if you started with anything else than an loa4. 

However, this example certainly shows that out of any bvh collections, the native production is probably only a very rough starting point with lots of work left to adapt the captured motion to a usable playback character. 

So (from the Peanut Gallery), please do not run that non-conforming skeleton as a conforming hanim character anymore unless, If you really can’t get conforming x3d hanim skeleton as playback, then please don’t archive as hanim without proper bvh skeleton Disclaimer. 
Again, just convert to use the ‘standard’ loa4 as the target playback, at humanoid scale. Then, if interesting, the animations can be extracted for use in a legal skeleton and coded for realtime rather than videotime. Please don’t just simply recreate the bvh-encoded skeleton – convert directly to loa4 at human scale and then you can see what you really have.  

Please note one advantage of the typical video frame rate seen in these animation thingees, is that to make a video from these your player does not need to use interpolators since you give it the exact keyframe interval data. 

More fun with realtime hanim. 

Best regards,
Joe

From: John Carlson
Sent: Friday, October 28, 2022 2:53 PM
To: Joe D Williams; Norbraten, Terry (CIV)
Cc: Brutzman, Donald (Don) (CIV)
Subject: Re: BVH to X3D Conversion bug

Last i heard, HAnim is acceptable.  Joe can confirm, cced.

On Fri, Oct 28, 2022 at 10:00 AM Norbraten, Terry (CIV) <tdnorbra at nps.edu> wrote:
One issue is that the BVH converter is not translating the correct level for H-Anim. 

The Pirouette.x3d has

<component level='1' name='HAnim’/>

Should be

<component level='1' name=‘H-Anim’/>   <<< require the hyphen 

On Oct 28, 2022, at 05:59, Brutzman, Donald (Don) (CIV) <brutzman at nps.edu> wrote:

Thank you John for excellent logs and sleuthing.
 
Terry, the error immediately jumping out at me is the following.  At least one library is not getting bundled properly.
 
• java.lang.ClassNotFoundException: javax.vecmath.Vector3d
 
Great discussion yesterday Terry, thanks.  I have created the pre-release file site at
 
• https://sourceforge.net/projects/x3d/files/X3D-Edit%20Pre-Release%20Testing/
 
all the best, Don
-- 
Don Brutzman  Naval Postgraduate School, Code USW/Br        brutzman at nps.edu
Watkins 270,  MOVES Institute, Monterey CA 93943-5000 USA    +1.831.656.2149
X3D graphics, virtual worlds, Navy robotics https:// faculty.nps.edu/brutzman
 
From: John Carlson <yottzumm at gmail.com> 
Sent: Thursday, October 27, 2022 12:09 PM
To: Brutzman, Donald (Don) (CIV) <brutzman at nps.edu>; Norbraten, Terry (CIV) <tdnorbra at nps.edu>
Subject: Re: Trying new download--X3D-Edit 4
 
NPS WARNING: *external sender* verify before acting.
 
I have confirmed the Pirouette.bvh in archives and pirouette.bvh are the same, essentially, just different whitespace.   I will now try to see if X3D-Edit will load the archive version. 
 
Attached are the logs that are showing up in Windows 10 X3D-Edit dev/var/log.
 
I haven't looked into them yet, I will now move to Linux.
 
If you could send me the X3d-Edit steps how to convert BVH to X_ITE and X3DOM, that would be great.
 
Forward old email if necessary.


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