[X3D-Public] HTML5 Recommendation Additions for Integrating X3DGraphics

[Don Brutzman]

Thanks for your in-depth review and multiple comments Joe.

Joe D Williams wrote:
> Add a new line as follows:
> 
>   The X3D namespace is: http://www.web3d.org/specifications/x3d

We have been using schema-specific namespaces for each version of X3D.
Somewhat differently than HTML, because X3D has continued to evolve
and gain new extensions, our vocabulary keeps growing.

Details regarding X3D namespace definitions can be found in
X3D Extensible Markup Language (XML) encoding specification,
Section 4 Concepts
http://www.web3d.org/x3d/specifications/ISO-IEC-19776-1.2-X3DEncodings-XML/Part01/concepts.html

Three legal examples:

<X3D profile='Immersive' version='3.2'
xmlns:xsd='http://www.w3.org/2001/XMLSchema-instance'
xsd:noNamespaceSchemaLocation='http://www.web3d.org/specifications/x3d-3.2.xsd'>

<X3D profile='Immersive' version='3.1'
xmlns:xsd='http://www.w3.org/2001/XMLSchema-instance'
xsd:noNamespaceSchemaLocation='http://www.web3d.org/specifications/x3d-3.1.xsd'>

<X3D profile='Immersive' version='3.0'
xmlns:xsd='http://www.w3.org/2001/XMLSchema-instance'
xsd:noNamespaceSchemaLocation='http://www.web3d.org/specifications/x3d-3.0.xsd'>

Overloading a URI label for the namespace with the actual URL address for the
schema is considered an acceptable and not-uncommon practice in schema design.
Certainly it reduces ambiguity for authors and some tools.  Nevertheless some
people in the XML world use a different approach.  Further discussion is likely
needed.  Some has occurred on HTML bug 8238, see end of comment #4 and after.
http://www.w3.org/Bugs/Public/show_bug.cgi?id=8238#c4

Raising this as a spec issue gives us a chance to reach consensus with the HTML5
group regarding the best practice for our case.  It is possible we might want
to change the current namespaces defined above - but will have to ensure that
tools will use the right schema to validate scenes appropriate to each version.
As a starting point, the proposal gives an unused url as a common namespace
identifier:

	The X3D namespace is: http://www.web3d.org/specifications/x3d
http://www.web3d.org/x3d/content/html5/HTML5RecommendationAdditionsForX3D.html#issue-q

I hope this explains the background details of the issue, hopefully more work
will follow.

>   I thought we had a nice landing page for that.

the References section lists:

X3D Specifications
	page provides the full set of of approved specification documents.
	http://www.web3d.org/x3d/specifications

X3D DTDs and Schemas
	formally define X3D syntax for use by any XML tool.
	http://www.web3d.org/specifications
	(this directory links to a manually updated index.html page)

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  work +1.831.656.2149
X3D, virtual worlds, underwater robots, XMSF  http://web.nps.navy.mil/~brutzman