Generalized Resources in XML3D

Hello,

no discussion on the mailing list for some time. Thus I would like to 
raise a topic that seems to become more important and is strongly 
related to the discussion on transmission formats.

We recently published a paper at SEARIS 2013 [1] that explains the 
architecture of xml3d.js. It's not directly related to the general 
Polyfill architecture that we propose in the CG but rather explains the 
concrete implementation of xml3d.js. It's very technical. But an 
interesting topic for our Dec3D discussion is the _generalized resource 
concept_, that we (finally) introduced in xml3d.js and that is 
interesting for our initiative. I think, the general tendency in XML3D 
as well as in X3DOM is to mix DOM representation with external data. IGD 
has developed some interesting transmission formats and we have a simple 
but powerful concept to use these (and other) formats in a generic way. 
Here a very simple example:

1. Intra-document references:
<mesh type="triangles" src="#teapot-data"/>

The data is really in the DOM and freely accessible using the DOM API or 
libraries such as jQuery

2. External references to a single entity:
<mesh type="triangles" src="teapot.json"/>

The whole mesh data set in a document, the document has no other 
information than the mesh data

3. External references to a structured document:
<mesh type="triangles" src="primitives.xml#teapot"/>

The concept is recursive, i.e. a structured document can itself contain 
references again. In XML3D, the concept not only works for meshes, but 
also for material descriptions, transformations, light parameters etc. 
In combination with Xflow, it allows for dynamic attributes. We have 
shown, that this concept can even work with more complex mesh encodings 
such as SIG (using smart shader compositing).

This might not be too relevant for hand-crafted scenes, but is very 
powerful in client-server architectures, especially in a REST context. 
For instance, it allows to adapt the data transmission during runtime. 
On the other hand, if you need specialized nodes for each transmission 
format (IndexedFaceSet, ImageGeometry etc), one moves this logic to 
application level (adding/removing node instances at runtime).

It fits very well to other W3C initiatives, where the composition of 
HTML documents from several source is becoming increasingly important. 
Maybe this could also be a concept for X3D 4.0?

Best regards,
Kristian

[1] http://www.searis.net/index.php5/Main_Page

--
________________________________________________________

Kristian Sons
Deutsches Forschungszentrum für Künstliche Intelligenz GmbH, DFKI
Agenten und Simulierte Realität
Campus, Geb. D 3 2, Raum 0.77
66123 Saarbrücken, Germany

Phone: +49 681 85775-3833
Phone: +49 681 302-3833
Fax:   +49 681 85775–2235
kristian.sons@dfki.de
http://www.xml3d.org

Geschäftsführung: Prof. Dr. Dr. h.c. mult. Wolfgang Wahlster (Vorsitzender)
Dr. Walter Olthoff

Vorsitzender des Aufsichtsrats: Prof. Dr. h.c. Hans A. Aukes
Amtsgericht Kaiserslautern, HRB 2313
________________________________________________________

Received on Monday, 22 April 2013 13:16:26 UTC