[x3d-public] [x3d] Spec Comment by on 19775-1: X3D Architecture - V4.0:component support needed for glTF inline loading conversion

[Michalis Kamburelis]

Note that we already edited that statement in
https://www.web3d.org/documents/specifications/19775-1/V4.0/Part01/components/networking.html
--  it's "Lighting component level 3" (not 4 as in spec comment) and
we list "Minimum required glTF support".

Looking at that "Minimum required glTF support" it implies the need to support:

- Shape:2, Lighting:3 as already stated there
- Grouping:1 (already mentioned as "Prerequisites" for Networking:2 though)
- Rendering:3 or Geometry3D:2 (you need *some* way to render meshes
composed from any triangles, obviously)

This does not cover "what do you need to convert 100% of glTF into
X3D", because we do not know the answer to that yet.

The best attempt at mapping glTF->X3D is on
https://github.com/michaliskambi/x3d-tests/wiki/Converting-glTF-to-X3D
that I linked om this list before. It lists my knowledge (and thus
CGE/view3dscene implementation) and has bits of knowledge about what
X3DOM is doing. I welcome other implementors to review it and modify
-- what are *you* doing, and if you're doing something else -- write
*why*. Edit wiki, or just write email to me.

But that wiki page does not cover everything from glTF, we're not
there yet. Some things require research. Some things are more obvious
how to do (we could probably get consensus about them easily), but
still require adding it to spec at some point (like Tangent node or
X3DColorNode.mode). I hope to work on them after X3D 4.0 (it takes
ages to finalize X3D 4.0, so at this point I very don't want to add
anything to X3D 4.0 :) ).

We'll get to a "nicely written and complete" mapping glTF->X3D at some
point, but this is still a work in progress. X3D 4.0 is in nice
position (with PhysicalMaterial and many other things matching glTF)
but we still have way to go. Both implementations (including my own)
and the spec.

Regards,
Michalis

pon., 2 maj 2022 o 00:06 Joseph D Williams <joedwil at earthlink.net> napisał(a):
>
> Maybe this needs a nice graph that links standard gltf data asset fields to certain x3d native data fields and those that are ‘compiled’ containers of data derived from certain x3d fields.
>
> Thanks
>
> Joe
>
>
>
> From: Brutzman, Donald (Don) (CIV)
> Sent: Monday, April 25, 2022 8:15 AM
> To: Andreas Plesch
> Cc: Spec Feedback; X3D Public Mailing List (x3d-public at web3d.org); x3d at web3d.org
> Subject: Re: [x3d] Spec Comment by on 19775-1: X3D Architecture - V4.0:component support needed for glTF inline loading conversion
>
>
>
> [cc: x3d-public]
>
>
>
> Thanks for insightful comment.  Happy to modify this statement to list all
>
> appropriate components, possibly Immersive profile.
>
>
>
> Michalis, do you have any opinions from writing your glTF->X3D conversion
>
> code?
>
>
>
> It helps to know full coverage.  If there is a glTF test file that includes
>
> all constructs, that would also be helpful to convert and add to our
>
> architecture.
>
>
>
> 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
>
>
>
> -----Original Message-----
>
> From: x3d <x3d-bounces at web3d.org> On Behalf Of Spec Feedback
>
> Sent: Thursday, April 21, 2022 12:47 PM
>
> To: x3d at web3d.org
>
> Subject: [x3d] Spec Comment by on 19775-1: X3D Architecture - V4.0
>
>
>
> -- Submitter indicates that this comment may be public: *Yes* --
>
>
>
> Comment on 19775-1: X3D Architecture - V4.0
>
>
>
> https://www.web3d.org/documents/specifications/19775-1/V4.0/Part01/component
>
> s/networking.html#X3DUrlObject
>
>
>
> -----------------
>
> "Support for loading glTF assets (see 2.[GLTF]) also requires support for
>
> Shape component level 2 and Lighting component level 4."
>
>
>
> Many different data fragments may be contained in the current standard gltf
>
> asset structure, even animation data, so maybe also more general statement?
>
>
>
>
>
>
>
> -----------------
>
>
>
> Submitted on Thursday, 2022,  April 21 - 12:47pm by  (Joe D Williams )
>
> IP: 12.206.82.58
>
>
>
> See: https://www.web3d.org/node/1694/submission/5663
>
>
>
>
>
> _______________________________________________
>
> x3d mailing list
>
> x3d at web3d.org
>
> http://web3d.org/mailman/listinfo/x3d_web3d.org
>
>
>
> _______________________________________________
> x3d-public mailing list
> x3d-public at web3d.org
> http://web3d.org/mailman/listinfo/x3d-public_web3d.org