[x3d-public] several #'s in the same URI (we know about several URIs in a url attribute).

[John Carlson]

What’s the status on updating .x3d examples with 2 #’s in a single URI (not url, I know that)?  Also, there is an example with spaces in the URI (for a filename).  I could create a format which matches several URIs for the url field, if needed.

I’ll try to find the email with the example data.  brb

John
> On Feb 3, 2016, at 6:08 AM, Don Brutzman <brutzman at nps.edu> wrote:
> 
> [cc: community for general authoring interest]
> 
> On 2/2/2016 6:49 PM, John Carlson wrote:
>> JSON looks fine now. What’s the purpose of mentioning each URI twice for ScalarDamper? Something to do with ExternProtos?
> 
> Four times actually: local then remote url for .x3d version, followed by local then remote url for .wrl version.
> 
> - local for efficiency/speed on local client or web server when using a collection.
> - remote for interoperability when inspected in isolation (such as an email attachment).
> - preferential retrieval of .x3d but .wrl also available for backwards compatibility with older players.
> 
> This is why _X3D url lists are better than html url values_. Linked content becomes portable.
> 
> More details on url best practices for X3D at
> 
> 	X3D Scene Authoring Hints: URL Links
> 	http://www.web3d.org/x3d/content/examples/X3dSceneAuthoringHints.html#urls
> 
> "Eat your spinach" factor:  the X3D Validator will nag if your scene only has one url value.  If content is king, then good content is good to have.
> 
> 	https://savage.nps.edu/X3dValidator
> 
> 
> [...]
>>> Also
>>> http://www.web3d.org/x3d/content/examples/Basic/Followers/FollowerExternalPrototypeDeclarations.x3d
>>> 
>>> <ExternProtoDeclare name='PositionDamper' url='"urn:inet:hersto.net:node:PositionDamper" "Dampers.wrl#PositionDamper" "http://www.hersto.net/Followers/Dampers.wrl#PositionDamper"'>
>> 
>>> The URNs are questionable but they are defined by IETF and endorsed by W3C and included in VRML/X3D specifications.  Not sure if anyone uses them anymore.
>>> 
>>> RFC 2141: URN Syntax
>>> https://www.ietf.org/rfc/rfc2141.txt
>>> URIs, URLs, and URNs: Clarifications and Recommendations 1.0
>> 
>>> Report from the joint W3C/IETF URI Planning Interest Group
>>> W3C Note 21 September 2001
>>> https://www.w3.org/TR/uri-clarification
>> 
>>> Roy and I got started on an X3D Regexes page.  We will return to that when other X3D Schema work in progress is complete.  Skeleton at
>> 
>>> http://www.web3d.org/specifications/X3dRegularExpressions.html
>> 
>>> If you look inside the X3D Schema, you will find a number of regexes for X3D datatypes in there already.  XML Schema does let you define a regex to validate special types, so this is a worthwhile future task.
> 
> 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