[x3d-public] X3D minutes 20 SEP 2019: X3DMetadataObject/X3DUOM, specs diagram update, annotations, field naming

Brutzman, Donald (Don) (CIV) brutzman at nps.edu
Fri Sep 20 09:33:12 PDT 2019

Here are minutes for X3D Working Group meeting Friday 20 SEP, 08-0930 pacific.  (Connection information below.)

Attendees:  Anita Havele, Vince Marchetti, Nicholas Polys, Dick Puk, and Don Brutzman.

Participation eligibility: Web3D Consortium members + invited experts. (Are you ready to volunteer? We are moving out smartly.)

Recent meeting minutes:

* [x3d-public] X3D minutes 6 SEP 2019: DICOM discussion, overview diagram review, ISO meeting highlights, API progress, defer STL/OBJ support

* [x3d-public] X3D Working Group minutes 21 AUG 2019: glTF X3D specification Plan Of Action Milestones (POAM)



0. Progress and problem reports.  What else is new?!  8)

a. Anita led a good discussion of active discussion by Web3D leadership.


1. (from prior meeting) *X3Dv4 DICOM Profile* with OBJ support proposed on medical working group mailing list, discussed in CAD Design Printing Scanning meeting.
> *Resolution* - we agreed to clearly focus our X3Dv4 efforts: confirmed yes to glTF, but no to STL and OBJ unless someone outside the core implementers takes the time to provide commonly usable converters and specification prose.
Subsequent discussions in Design Printing Scanning call indicate that some kind of DICOM alignment remains a desirable capability, and a possibility that can be considered in the future.  Creating a Javascript-based X3D prototype for loading OBJ, and for showing how such 3D compatibility for OBJ files can work in X3DOM and X_ITE is a good way to proceed.
- TODO check X3DOM, Castle Game Engine, other X3D tools for possible OBJ loading support already.
- STL, PLY, and similar simple mesh formats might be trivial to map model data into an X3D geometry (e.g. prototype mesh -> IndexedFaceSet).
- Avoiding JavaScript file loading in the browser still allows testing, a prototype can just be given the polygonal data.

For a putative DICOM profile, essentially what are the narrow requirements for an X3D scene to map to proposed DICOM OBJ components.  It would not include unnecessary aspects like glTF, physically based rendering (PBR), or other advanced techniques. Certainly helpful might be some example scenes - perhaps from 3DMD or DICOM itself?

There are multiple ways to put the puzzle pieces... divide and conquer, getting clear on what might occur is useful.  No current commitment in X3Dv4, we are focusing on priorities.  Others are welcome to progress such capabilities further and bring them back to the group in the future, if desired.

Still TODO: Don will update Mantis regarding STL/OBJ and Dick will review on next editors call.

Upcoming: Michalis will likely have an update on advanced lighting, PBR and glTF in a few weeks.


2. *Email report on X3DUOM*

	[x3d-public] X3DMetadataObject refactoring for X3D XML Schema, X3DUOM, X3DJSAIL and X3D Ontology progress

A significant and subtle twist was unraveled in that X3DMedataObject is simply an interface and should not inherit from abstract node type X3DNode.

	X3Dv4 XML Schema documentation: X3DMetadataObject

This simplifies several constructs in X3DUOM, XML Schema, and derived APIs.  There may be some further positive impacts on Shader and Layout nodes, further analysis to follow.

Hopefully unremarkable, no changes to content are expected.  Review discussion showed how this is maturing our implementations, confirming X3D specification design, and not changing any X3D content.


3. (from prior meeting) Takamatsu meeting quicklook.

> - Humanoid Animation (HAnim) approvals by ISO editors, defenestration of hyphenization for enumeration *HAnim*.
> - Medical progress: representing human organs using HAnim, big strategy is possible, HL7 collaboration.
> - Smart Cities opportunities abound in future: X3D as connection and presentation layer for many things.
> - ISO requested to go open on Mixed Augmented Reality (MAR) specifications.  Bodes well for X3Dv4.1.
> - Khronos cooperative dialog and activity continues well.
> - Reopened issue: Vince and Don are following up on JTC1 joint group on 3D printing and scanning.
> Expect to distribute a number of meeting materials following discussion and review by Web3D Board of Directors.  Membership has value! 8)

Release of meeting reports is pending following BoD review.  We will first send to Web3D members - membership has value!


4. Standards Relationships diagram - proposed update review, see attached comparison in last weeks agenda.

Just refinements, no major changes.  Flipping in full-screen mode makes differences easy to compare.

 From prior meeting minutes, attachment:


Summary of changes:
a. MAR specifications need to go open, otherwise no Web3D feedback
b. WebXR appears to be progressing (TODO note current timeline)
c. HAnim facial modeling fairly mature, no updates
d. Internal organ visualizations deserve further consideration, could map directly to
- HAnimJoint, HAnimSegment for centerline/skin,
- HAnimSite for feature points and for organ connections, showing overall systems,
- HAnimDisplacer HAnimMotion for animation of organs.
e. Work in progress, figure out how to best specify:  X3DUOM and X3D Ontology
f. Medical content: all draft and varied work in progress (make lines dotted).

Good discussion and some improvements - thanks! Will update and publish.


5. /Field name changes/ for improved consistency, affects child SF/MFNode field naming for ~10 nodes.

	Potential future changes for improved consistency of field names

These proposed changes grow out of the exhaustive listing (and strong validation typing) of the cases where XML containerField (i.e. field name) variations might occur.

These changes appear to bo necessary variations on X3Dv4 syntax proposed to avoid unintended mismatches by authors and also  achieve unified field representations in X3Dv4 codebase APIs.

Considering /aliases/ for forward/backwards compatibility might be a good way to ensure that prior-version content can coexist without changes.  It would also give tools a chance to catch up.
- TODO: worth looking at how aliases can work.
- TODO: did HTML5/DOM use this rationale in any of their changes from HTML4?

Primary discussion topic this week - good review, further refinement to follow.


6. *glTF X3D Features Comparison*. Would anyone like to lead this review update?

> * Attachment [3]: glTF X3D Features Comparison (3 NOV 2017)
>    https://www.web3d.org/sites/default/files/page/X3D%20Version%204%20Strategy/glTfX3dFeaturesComparison.pdf
> * source at
>    https://docs.google.com/spreadsheets/d/12ebxqfQoFPuNhaz8wZkNE6G-w_bqt98iy6p5F9IazVM/edit#gid=0

This is useful, and the comparison task still available for a serious glTF-X3D user.

Don has done a preliminary table review, will offer an improved table layout.

We will look at this again following next review of Michalis' work on glTF and PBR and advanced lighting in X3Dv4.


7. *Annotations component*.  Node refactoring for clarity and conciseness proposed, spec prose changes posted.

This draft was written 10 years ago so all improvements are welcome.  Request feedback, good discussion today.

	[x3d-public] X3Dv4 Annotation Component revision, request review

Refinement of key questions:

a. What is the scope of an annotation?  Does it affect it's parent, i.e. peers and their childen?  For example, how would you annotate an IFS if the annotation can only get inserted into scene graph as a peer of the containing Shape node?

b. Can we move url field to 42.3.1 X3DAnnotationNode and then omit 42.4.6 URLAnnotation?  This refactoring would simply overall design, and allow any annotation to be either local (children) or external (via url).

c. Text annotation might be plain text, styled text (HTML fragment or possibly markdown), XML, etc.

d. Can we better rename 42.4.3 GroupAnnotation node as InlineAnnotation or ModelAnnotation?  (The name GroupAnnotation is ambiguous and seems to imply that it is grouping annotations themselves.)  Note this is directly related to scoping question.

e. Can we better rename 42.4.4 IconAnnotation as ImageAnnotation? (The term "icon" implies characteristics such as small size or mostly square, but the node had no such restriction.)

f. Examples are definitely needed.  Prototypes are certainly possible here to show node design working coherently.

g. Conceivably this might be legitimately deferred to X3Dv4.1 because correct use of annotations is quite important in XR and MAR contexts.  But it seems close and if done right, the annotations would work satisfactorily with any user-interface modality.


8. *X3Dv4 topics*

	X3Dv4 Implementations Status

a. /API Progress Review/ with special thanks to Masaki Aono and Myeong Won Lee.

> Status of Web3D drafts and submissions to ISO:
> * We do have NWIPs and prior draft documents at
>    https://github.com/Web3DConsortium/X3D/tree/master/ISO-IEC19777
> * Specification timeline spreadsheet
>    https://docs.google.com/spreadsheets/d/1GdVcjQIid0Hohc_ajmepVOESy2sLtHSVvbvsFni89w8/edit#gid=1641828106
> We have sent a query to Dr. Myeong Won Lee to see if she is already working on updating the existing drafts.

We noted the presence of prior drafts in github for C/C++/C#.  Update status is still unknown.

We are still working on Python design but making excellent progress, want to mature that further before writing draft spec prose.

> This was covered well at meetings of Web3D Korea Chapter last January and at SIGGRAPH last July.  TODO: get those slides online in a good place.

Standing by for slides: MWL please provide.

b. /Longer-term plan/: we hope to update 8-10 specs at approximately 1-month intervals next year.  The first will require very close scrutiny, the rest should be able to follow that basic pattern without too much difficulty.

b. Topic for next meeting: among the many emerging X3Dv4 capabilities that we are getting ready, can we identify a smaller set of topics that deserve broad marketing and outreach by Web3D Consortium as relevant to current market and business interests?


9. *Getting Connected*

Recently Web3D meetings have switched to Zoom channels, to good effect.  Zoom allows use of internet audio, screen sharing, and chat with links.

We meet regularly on Fridays 0800-0930 pacific.  Connection information is available for members on the following page.

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We got a lot done today.  No member-only topics discussed today.

Have fun with X3D!  8)

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 http://faculty.nps.edu/brutzman

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