[x3d-public] X3D minutes 14 May 2021: Web3D 2021, CAD STEP presentations, X3D-Edit, id attribute, XML SFString in MFString

[Don Brutzman]

Attendees: Vince Marchetti, Dick Puk, Don Brutzman

1. News and Progress Updates.

a. Web3D 2021 Conference meeting occurs every 2 weeks

Currently archiving Web3D 2020 as static pages, soon transitioning Web3D 2021 site.

[1.1] https://web3d.siggraph.org

[1.2] Web3D 2021 8 - 12 November 2021
       https://web3d2021.isti.cnr.it
       https://web3d2021.isti.cnr.it/submissions/

Due date for submission of papers, tutorials, Industrial Use Cases and Workshops is *30 July*.

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b. CAD presentations by Joint Working Group (JWG) 16 to SC4 STEP

This work has been long ongoing, focused on presentation and geometry services for CAD models.  X3D is one part of the solution space.

Tremendous slides and video presented by Jean Brange, Soonhung Han and Christophe Mouton with contributions by Vince Marchetti also.

We are looking to share these impressive assets publicly, hopefully next week.

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c. Continuing progress with X3D-Edit and X3D Validator

Several fixes applied, X3D-Edit beta testing continues...

X3D Validator we debugged an issue, so revisions of that software are expected next week.

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d. Propose upcoming meeting to discuss Blender export/import improvements

Team effort needed to improve Blender, several people have skills, can we get deliberate about it?

What is a good Friday, we could schedule 0800-0900 pacific (one hour before regular X3D meeting)

* Michalis Kamburelis, Andreas Plesch, Nicholas Polys, what day works for you?

Available dates: 21 May, 28 May, 11 June.

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e. X3D4 Architecture Committee Draft (CD) ballot comments not yet received, we are tracking that progress.  Once received we can plan on editors meetings.  Wondering if there will be a way for ISO participants to look at Mantis issues, perhaps through a guest account.

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2. Allowing id attribute on X3D nodes to facilitate usage with HTML

[2.0] allowing presence of /id/ attribute on X3D nodes to encourage model usage with HTML
       https://web3d.org/pipermail/x3d-public_web3d.org/2021-May/015181.html

We discussed the email.  The sense of things is that this is an option for models and not a requirement, no functional collisions intended or expected.

Open issue to be considered is whether it will be permitted in ClassicVRML encoding and SAI, to be reviewed when those specifications are being reviewed.

We'll allow a week or two consideration on the mailing list to play out.

Following that, we can then decide on XML encoding supporting /id/ similar to /style/ attribute.  The goal is not to require new or different functionality, rather simply allow this option to be included without provoking warnings/errors.

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3. Allowing unquoted SFString values in MFString array

Long-standing issue for X3D XML encoding, goal is hopefully to match functionality of parsing string payloads that is found in BNF grammar rules in ClassicVRML encoding.

Recent conceptual breakthrough in consolidating our shared understanding was that, after XML parsing rules are performed, we want values expressed in the X3D XML Encoding to be functionally equivalent to ClassicVRML encoding parsing.

If we can get to agreement, it seems to be a significant improvement in clarity and reliability of XML parsing of X3D models.  Intent is not break any existing model content that is following the rules.

[3.0] Mantis 1320: relax requirement for quoted single-string value in MFString array
       https://www.web3d.org/member-only/mantis/view.php?id=1320

We went through several curious examples illustrating relationships.  We should do more (perhaps in a table illustration or spreadsheet?) to illustrate further, since it is a tricky business to express these things unambiguously.

We will also need a number of X3D example scenes to illustrate these relationships already, we seem to have these already in X3D Examples Archives, deserves close checking.

Can we have some tricky examples for further exploration next week?

This is fundamental and thus deserves careful consideration to achieve common understanding and implementation.

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[deferred, follow-on issue]

4. XML encoding containerField default for MetadataSet in X3D4

TODO once prior issue resolved, hopefully next week...

[4.0] Mantis 1283: XML encoding: change X3D4 MetadataSet default containerField='value' ?
       https://www.web3d.org/member-only/mantis/view.php?id=1283

There are a number of other simple MetadataSet mantis issues which might be quickly resolved when we look at this.

Especially noticeable for MetadataSet structures containing multiple MetadataString values and containerField.

[3.1] X3D Example Archives: X3D4WA, X3D for Web Authors, Chapter 15 Metadata
       XmpMetadataEmbedded.x3d model
       https://x3dgraphics.com/examples/X3dForWebAuthors/Chapter15Metadata/XmpMetadataEmbeddedIndex.html

Intend to show that verbose containerField approach is always correct, meaning it always matches the X3D4 Architecture.  The objective for XML encoding of X3D4 is to acceptably handle terse/omitted containerField usage.

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Next week Dick and Don will begin preparing preliminary-draft Proposed Disposition of Comments document for X3D4 CD ballot, facilitating the future editors editing.

Have fun with X3D4!  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