[x3d-public] thinking about X3DJSONLD/X3DOM/glTF interoperability - immutability, emitting events

[Don Brutzman]

Thanks for these earlier explorations and insights Andreas, very helpful.

Of especial note is #724 below.  Interesting alternative to extended Inline: perhaps using Shape node (or ExternalShape/ExternalGeometry/ExternalGroup, whatever best matches) to hold glTF content that is internally dynamic, externally immutable.

Conceptual question: can such a glTF node-group emit events?


On 7/6/2017 7:14 AM, Andreas Plesch wrote:
> 
>     Date: Thu, 6 Jul 2017 00:33:16 -0400
>     From: John Carlson <yottzumm at gmail.com <mailto:yottzumm at gmail.com>>
>     To: X3D Graphics public mailing list <x3d-public at web3d.org <mailto:x3d-public at web3d.org>>
>     Subject: [x3d-public] Fwd: thinking about X3DJSONLD/X3DOM/glTF
>              interoperability
> 
>     XSeen is taking the approach of treating glTF as a model.   What are others
>     doing?  Is anyone considering the whole scenegraph?  Why or why not?  Is
>     glTF as a model done because Three.js treats glTF as a mesh (I don't know
>     if three.js does this or not)?
> 
>     What do people think of the low level nature of glTF as opposed to X3D?
>     While it makes it less understandable, I can see how keeping glTF low level
>     would improve performance at the expense of file size.   Has anyone
>     compared and contrasted the two standards?
> 
>     Are there glTF importer/exporters for blender yet? If not, why not?
> 
>     John
> 
>     I'm thinking about glTF and X3DJSONLD interoperability since X3DOM is
>     starting to support glTF (I think).  What do you think the synergies might
>     be?
> 
> Yeah, I started to look into it:
> 
> https://github.com/x3dom/x3dom/pull/723
> https://github.com/x3dom/x3dom/issues/724
> 
> A-frame just uses Three which treats gltf more like a subscene, eg. very completely.
> 
> glTF is supposed to be more like JPG for complete 3d content. Dynamic but not mutable.
> 
> glTF can be binary, with a small file size.
> 
> The main difference to X3D is (lack of) events, eg. the kind of scene graph.
> 
> I would guess there is a blender gltf exporter, not necessarily importer.
> 
> It will be quite a job to produce a x3dom gltf2 external group/shape node.
> Perhaps the Three loader can be reused to some extent.
> 
> -Andreas
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