[x3d-public] Mantis 1530: Avoiding exhaustive EXPORT statements within HAnimHumanoid skeleton

Mon Apr 27 08:43:42 PDT 2026

Thanks for looking at this.  Topic certainly requires careful thought.

DEF identifiers are definitely needed for event ROUTEs, particularly for
PositionInterpolator and OrientationInterpolator.  This is not something
that can be removed without breaking legacy content and backwards
compatibility.

Writing a specialty node that does name lookup is an appealing concept.
I'd suggest the following approach:

   - X3D Script node that walks HAnimHumanoid tree(s) and creates ROUTE
   connections at run time,
   - inputs would be an input PositionInterpolator, an input MFNode array
   of OrientationInterpolator nodes, and a target HAnimHumanoid,
   - if single case works, can wrap it in a prototype definition and re-use
   it as an external prototype,
   - requires careful author testing, as ever, and
   - requires javascript support at run time

Interestingly, construction of such ROUTE connections might also be a
modeling task for authoring environments such as X3D-Edit, X3DJSAIL in
Java, X3DPSAIL x3d.py in Python, and other tools.

HAnimMotion node is a completely different approach and requires different
handling.  I'd like to build more examples (at some point) before
considering alterations to that implementation pattern.  It seems prudent
to avoid defining a new node until we have fully explored modeling and
extensibility options with the current architectures.

Have fun building HAnimHumanoid event graphs!  😁

all the best, Don
-- 
X3D Graphics, Maritime Robotics, Distributed Simulation
Relative Motion Consulting  https://RelativeMotion.info

On Mon, Apr 27, 2026 at 5:00 AM GPU Group <gpugroup at gmail.com> wrote:

> Q. does anyone need DEFs for joints?
> - HAnimMotion nodes can lookup the name field
> - when animating with interpolators, there can be a new node type
> HAnimMotionInterpolator and the interpolators route to the
> HAnimMotionInterpolator which can do the name lookup. like HAnimMotion node
> does.
> -Doug
>
> On Sun, Apr 26, 2026 at 10:49 PM Don Brutzman <don.brutzman at gmail.com>
> wrote:
>
>> This is a request for X3D browser implementers.
>>
>> Joe and I are making good progress on building models that add additional
>> bones/teeth/cartilage, providing a new LOA-5 for HAnim.  LOA-5 keeps
>> building on progressive Level of Articulation (LOA) 0..4 ranging from
>> simple to sophisticated HAnim models.
>>
>> We will soon be able to test EXPORT and IMPORT of HAnimHumanoid models in
>> full detail for use with multiple interpolator sets.  Our goal is to
>> demonstrate simplified sharing and composition of HAnim models in X3D.
>>
>> A recent improvement to X3D4 v4.1 draft was to deprecate USE nodes at the
>> top level of an HAnimHumanoid since they are superfluous, verbose, and
>> potentially error prone if defined incorrectly.
>>
>> Based on current efforts, we'd like to recommend something similar.  If a
>> HAnimHumanoid model is EXPORTed and then IMPORTed, the corresponding EXPORT
>> and IMPORT of every contained joint, segment and site is similarly
>> superfluous since such nodes are detectable automatically without
>> ambiguity.  HAnim naming conventions for matching prefixed DEF labels with
>> the corresponding name field in each given node are quite strict.  Thus
>> manually redefining hundreds of predictable EXPORT and IMPORT statements
>> for each re-use seems unnecessary.
>>
>> Thanks for considering this coding task.  It will have a notable
>> improvement on authoring simplicity, humanoid portability and model
>> robustness.
>>
>> The Mantis issue describing this proposal follows.
>>
>>    - Mantis 1530: Avoiding exhaustive EXPORT statements within
>>    HAnimHumanoid skeleton
>>    - https://mantis.web3d.org/view.php?id=1530
>>
>> Description Any HAnimHumanoid skeleton can have a lot of HAnimJoint and
>> HAnimSegment and HAnimSite children. For LOA-5, it is hundreds of such
>> children.
>>
>> These child nodes are always carefully identified, with pairwise DEF and
>> name fields that match exactly according to HAnim requirements.
>>
>> If an X3D model with an HAnimHumanoid includes an EXPORT statement
>> allowing re-use by other X3D scenes, then browsers need to automatically
>> EXPORT all of the subordinate HAnim nodes.
>>
>> Similarly, if a HAnimHumanoid is IMPORTed for animation re-use in a
>> different X3D scene, browsers need to automatically IMPORT all of the
>> subordinate HAnim nodes.
>> Additional Information Example:
>> - X3D Example Archives: Humanoid Animation, Bones, All Bones LOA 5
>> Skeletons
>> -
>> https://www.web3d.org/x3d/content/examples/HumanoidAnimation/Bones/AllBonesLOA5SkeletonsIndex.html
>>
>> see the EXPORT statements beginning at line 3286:
>>
>> https://www.web3d.org/x3d/content/examples/HumanoidAnimation/Bones/AllBonesLOA5Skeletons.html#3286
>>
>> 3286 <!-- right-side HAnimHumanoid -->
>> 3287 <EXPORT localDEF='hanimMesh_AllBonesSkeleton'
>> AS='AllBonesSkeletonMesh'/>
>>
>> 3288 <!-- left-side HAnimHumanoid -->
>> 3289 <EXPORT localDEF='hanim_AllBonesSkeleton' AS='AllBonesSkeleton'/>
>>
>> 3290 <!-- propose eliminating requirement for EXPORT statements
>> corresponding to child HAnimJoint HAnimSegment HAnimSite nodes, similar to
>> removing requirement for definition of USE nodes for HAnimHumanoid children
>> -->
>>
>> 3291 <EXPORT localDEF='hanim_c1' AS='AllBonesSkeletonMesh_hanim_c1'/>
>> 3292 <EXPORT localDEF='hanim_c1disc'
>> AS='AllBonesSkeletonMesh_hanim_c1disc'/>
>> 3293 <EXPORT localDEF='hanim_c2' AS='AllBonesSkeletonMesh_hanim_c2'/>
>> 3294 <EXPORT localDEF='hanim_c2disc'
>> AS='AllBonesSkeletonMesh_hanim_c2disc'/>
>> (etc. etc. approximately 400 EXPORT statements follow which exactly match
>> the skeleton example)
>> Tags  HAnim v2.1,  ,X3D v4.1
>> Attach Tags (Separate by ",")    Existing tags1356apacheCD Ballot commentDocument
>> styleExamplesfileHTML5JSONMantisMetaverseSAISchemasecurityserverspam
>> uploadV3.3 CommentV4.0V4.0 ResolutionValidationWebsiteWebXRX3DUOM
>>  Activities
>> <https://mantis.web3d.org/view.php?id=1530#>
>>
>>  brutzman <https://mantis.web3d.org/view_user_page.php?id=10>
>>
>>  2026-04-23 10:55
>>
>> administrator    ~0003889
>> <https://mantis.web3d.org/view.php?id=1530#c3889>
>> This issue is similar to the USE nodes in HAnimHumanoid - duplication by
>> authors is tedious, error prone, and a superfluous task that a browser can s
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>> Have fun with HAnim and X3D! 😁
>>
>> all the best, Don
>> --
>> X3D Graphics, Maritime Robotics, Distributed Simulation
>> Relative Motion Consulting  https://RelativeMotion.info
>>
>
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