[x3d-public] url MFString handling

Mon Apr 25 08:26:12 PDT 2022

On Sun, Apr 24, 2022 at 11:40 PM Brutzman, Donald (Don) (CIV)
<brutzman at nps.edu> wrote:
>
> Since case A is erroneous content, and X3D is mostly silent about specifying
> precisely how reactions to errors are performed, case B would be preferred
> robust behavior.

The question is if consistent browser behaviour should be required.
The idea is that url semantics (X3DUrlObject) are confined to the
ability of the browser to resolve, access and download urls. Content
viability and error handling is separate and managed in a later step
by the node (Inline, ImageTexture, ExternProto), just as any other
erroneous content. This is how authors and implementers would tend to
see it.

For Inline, x3dom would check if the downloaded file is valid xml or
json and has a Scene node. If not, it is considered an url failure and
treated the same as not resolvable urls. If it has a Scene node but is
not valid x3d, it is not considered an url failure and will generate a
parsing error and possibly exceptions but not try other urls.

For ImageTexture, x3dom would check if the url can be successfully
loaded by the HTML Image element, or is a .dds file.

> The author remains responsible for refresh periodicity, e.g. here is 10
> minutes
>
>    <Inline url = ' "./localDirectory/content.x3d"
> "https://SomeKindOfWeatherReport.com/content.x3d' autoRefresh="600"/>
>
> This issue is a little more involved since sequential handling of multiple
> url values might have security implications too.  Not sure if it possible to
> detect a retrieval from something like the following, but perhaps an
> additional autoRefresh precaution might limit exposure?  Not sure we can do
> anything about this, but worth a mention.
>
>    <Inline url = ' "./localDirectory/content.x3d"
> "https://man_in_middle_compromised_server/content.x3d' />

The main question I had is the scenario when initially
localDirectory/content.x3d was available but at some later point
became corrupt or removed. Should autorefresh enable then the second
url ? I think currently the spec. answer is yes. Sticking with the
initial url selection would be more predictable to a user (Why is
there suddenly a texture ? but perhaps then an author should just
provide a single url). Perhaps there should be a recommendation that a
browser should communicate any resource changes in the ui.

The cross-origin resource security policy (CORS) of HTML browsers is
an attempt to mitigate such security concerns. It establishes a method
where both client and server have to explicitly agree that it is ok to
request, serve and accept network data. One option may be to adopt
CORS for X3D. For X3D browsers on a web page CORS is automatically
enforced (unless willfully circumvented with proxy servers).

-Andreas

> Dick and I will examine prose closely when reviewing resolution wording.
> Meanwhile thanks for all helpful comments.
>
> 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: Andreas Plesch <andreasplesch at gmail.com>
> Sent: Sunday, April 24, 2022 8:21 PM
> To: Brutzman, Donald (Don) (CIV) <brutzman at nps.edu>
> Cc: Joseph D Williams <joedwil at earthlink.net>; X3D Graphics public mailing
> list <x3d-public at web3d.org>
> Subject: Re: [x3d-public] url MFString handling
>
>
> Here is a simple example to illustrate the question:
>
> <Inline url = ' "existing_Image.jpg"
> "https://accessible_server/content.x3d" ' />
>
> Should content.x3d be loaded and added to the scene or should
> existing_Image.jpg be downloaded, interpreted and found to be not a legal
> x3d document by the browser, and therefore nothing be loaded ?
>
> In other words, should option
>
> A) <Inline url = ' "existing_Image.jpg" ' /> (leading to an error which a
> Loadsensor can pick up) or
> B) <Inline url = ' "https://accessible_server/content.x3d" ' />
>
> be considered equivalent ?
>
> My initial answer was mostly option B) (except for some corner cases), Joe
> suggested option A) since url semantics are mostly about downloadability,
> not correct content, and I then welcomed Joe's suggestion. Probably most
> browsers implement A).
>
> If B) is the targeted answer, then the current spec. language is ok.
> However, if A) is the targeted answer, then spec. language should avoid the
> word "interpretable" and add 'accessible' or 'resolvable' as often used with
> urls, in my view.
>
> -Andreas
>
> On Sun, Apr 24, 2022 at 9:58 PM Brutzman, Donald (Don) (CIV)
> <brutzman at nps.edu> wrote:
> >
> > I think that any failure is a failure.  Can't proceed with half-baked
> content.
> >
> >
> >
> > Since this is an object interface, it is written in an attempt to be
> content-neutral, which means suitable for run-time interpretation of
> multiple content types: X3D VRML images sounds movies etc.
> >
> >
> exis> 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
> >
> >
> >
> > From: Joseph D Williams <joedwil at earthlink.net>
> > Sent: Sunday, April 24, 2022 5:34 PM
> > To: Brutzman, Donald (Don) (CIV) <brutzman at nps.edu>; Andreas Plesch
> > <andreasplesch at gmail.com>
> > Cc: X3D Graphics public mailing list <x3d-public at web3d.org>; Brutzman,
> > Donald (Don) (CIV) <brutzman at nps.edu>
> > Subject: RE: [x3d-public] url MFString handling
> >
> >
> >
> > Hi Don and All.
> >
> > I was thinking the problem was determining how much checking the browser
> needs to do when it first laads the file, then when 'interprets' the user
> code for loading into the scene. For loadsensor it seems like all it has to
> do is make sure the profile is covered, then a failure in further loading is
> a different problem. Again, if the profile is ok but the file has other
> problems leading to error, does the next file get attempted? Is this
> different if loadsensor is not present?
> >
> > Thanks,
> >
> > Joe
> >
> >
> >
> >
> >
> >
> >
> > From: Brutzman, Donald (Don) (CIV)
> > Sent: Sunday, April 24, 2022 4:44 PM
> > To: Andreas Plesch; Joseph D Williams
> > Cc: X3D Graphics public mailing list; Brutzman, Donald (Don) (CIV)
> > Subject: RE: [x3d-public] url MFString handling
> >
> >
> >
> > Thanks for looking hard at this.
> >
> >
> >
> > Am thinking we might simply remove "X3D browsers only have to
> > interpret a
> >
> > single string." ...
> >
> >
> >
> > Or perhaps to rephrase it better as intended, that once a single
> > success is
> >
> > encountered, there is no need to retrieve further content.
> >
> >
> >
> > "X3D browsers only need  to satisfactorily interpret content
> > corresponding
> >
> > to a single string in the url list.  Retrieving all versions of url
> > content
> >
> > is not necessary."
> >
> >
> >
> > 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-public <x3d-public-bounces at web3d.org> On Behalf Of Andreas
> > Plesch
> >
> > Sent: Friday, April 22, 2022 8:32 AM
> >
> > To: Joseph D Williams <joedwil at earthlink.net>
> >
> > Cc: X3D Graphics public mailing list <x3d-public at web3d.org>
> >
> > Subject: Re: [x3d-public] url MFString handling
> >
> >
> >
> > For future reference:
> >
> >
> >
> > On Thu, Apr 21, 2022 at 4:43 PM Andreas Plesch
> > <andreasplesch at gmail.com>
> >
> > wrote:
> >
> > >
> >
> > > On Thu, Apr 21, 2022 at 4:04 PM Joseph D Williams
> > > <joedwil at earthlink.net>
> >
> > wrote:
> >
> > > >
> >
> > > >> Let me propose that getting rid of "interpret" would suffice:
> >
> > > >
> >
> > > > Maybe 'resolve"?
> >
> > >
> >
> > > Some tweaks:
> >
> > >
> >
> > > "All url fields can hold multiple string values. The strings in
> > > these
> >
> > > fields indicate multiple locations to search for data in the order
> >
> > > listed. If the browser cannot locate the data specified by the first
> >
> > > string, it shall try the second and subsequent locations in order
> >
> > > until a resolvable location containing data is encountered. X3D
> >
> > > browsers only have to load a single location. If no loadable
> > > locations
> >
> > > are found, the node type defines the resultant default behaviour."
> >
> > >
> >
> > > > Meaning the file name has been found and delivered to the browser
> > > > and
> >
> > ready to be loaded into the calling context?
> >
> > > >
> >
> > > > Autorefresh sort of complicates things a bit, so now I am looking
> > > > for
> >
> > something "file found and loaded" Autorefresh must not try to reload
> > if the
> >
> > loaded file content fails.
> >
> > >
> >
> > > Good point. I am not familiar with the motivation behind introducing
> >
> > > autorefresh. I think the expectation would be that only the
> > > initially
> >
> > > selected url would autorefresh, eg. that browsers would not be
> >
> > > required to test all supplied locations to determine if a higher
> >
> > > priority one became available after each refresh.
> >
> >
> >
> > It appears that retrying all urls on refresh was deemed preferable:
> >
> >
> >
> > https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4-CD1/P
> > art01/
> >
> > components/networking.html#X3DUrlObject
> >
> >
> >
> > That means, on refresh:
> >
> >
> >
> > 1) Use currently selected url
> >
> > 2) If that fails, try all urls in order
> >
> > 3) If that fails, do nothing
> >
> >
> >
> > This is a bit more complicated than A)
> >
> >
> >
> > 1) Use currently selected url
> >
> > 2) If that fails, do nothing
> >
> >
> >
> > or, alternatively B)
> >
> >
> >
> > 1) do the same as when initially loaded: try all urls in order
> >
> >
> >
> > Since autorefresh probably targets regular updates of an existing
> > resource
> >
> > (say an image of a weather forecast), option A) seemed sufficient and
> > also
> >
> > more predictable. Let's see how it goes when there is time.
> >
> >
> >
> > Andreas
> >
> >
> >
> > > -Andreas
> >
> > >
> >
> > > > Thanks,
> >
> > > >
> >
> > > > Joe
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > From: Andreas Plesch
> >
> > > > Sent: Thursday, April 21, 2022 12:46 PM
> >
> > > > To: Joseph D Williams
> >
> > > > Cc: X3D Graphics public mailing list
> >
> > > > Subject: Re: [x3d-public] url MFString handling
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > Hi Joe,
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > Thank you for your response which makes a lot of sense to me.
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > This urls feature really only handles problems with finding the
> > > > > file
> >
> > and delivering contents, not dealing with the validity of actual
> > contents of
> >
> > the file.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > Yes, I agree. This role should be clearly pointed out. The first
> >
> > > > file
> >
> > > >
> >
> > > > which can be found and accessed should be considered selected for
> >
> > > >
> >
> > > > further processing which then may lead to failure.  Unfortunately,
> > > > I
> >
> > > >
> >
> > > > think currently the spec. language is more vague.
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > https://www.web3d.org/documents/specifications/19775-1/V3.3/Part01
> > > > /c
> >
> > > > omponents/networking.html#X3DUrlObject
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > says:
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > "All url fields can hold multiple string values. The strings in
> >
> > > > these
> >
> > > >
> >
> > > > fields indicate multiple locations to search for data in the order
> >
> > > >
> >
> > > > listed. If the browser cannot locate or interpret the data
> > > > specified
> >
> > > >
> >
> > > > by the first location, it shall try the second and subsequent
> >
> > > >
> >
> > > > locations in order until a location containing interpretable data
> > > > is
> >
> > > >
> >
> > > > encountered. X3D browsers only have to interpret a single string.
> > > > If
> >
> > > >
> >
> > > > no interpretable locations are found, the node type defines the
> >
> > > >
> >
> > > > resultant default behaviour."
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > Let me propose that getting rid of "interpret" would suffice:
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > "All url fields can hold multiple string values. The strings in
> >
> > > > these
> >
> > > >
> >
> > > > fields indicate multiple locations to search for data in the order
> >
> > > >
> >
> > > > listed. If the browser cannot locate the data specified by the
> > > > first
> >
> > > >
> >
> > > > string, it shall try the second and subsequent locations in order
> >
> > > >
> >
> > > > until a location containing data is encountered. X3D browsers only
> >
> > > >
> >
> > > > have to load a single location. If no accessible locations are
> >
> > > > found,
> >
> > > >
> >
> > > > the node type defines the resultant default behaviour."
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > Happy to iterate if desired,
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > Andreas
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > As for json and gltf, same thing. Runtime expects the delivered
> > > > > data
> >
> > to  be legal contents as defined by the author. If the data is wrong,
> > like
> >
> > some stuff not matching, then, something else fails, not the loading
> >
> > process.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Thanks for all on this, Andreas,
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Joe
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > From: Andreas Plesch
> >
> > > >
> >
> > > > > Sent: Thursday, April 21, 2022 10:06 AM
> >
> > > >
> >
> > > > > To: X3D Graphics public mailing list
> >
> > > >
> >
> > > > > Subject: Re: [x3d-public] url MFString handling
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Are there suggestions on how to handle back-up "#viewpoint"
> > > > > style
> >
> > > > > urls
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > for Anchor in case Viewpoints with matching def names do not exist ?
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > https://www.web3d.org/documents/specifications/19775-1/V3.3/Part
> > > > > 01
> >
> > > > > /components/networking.html#Anchor
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > paragraph nine explains that in this case:
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > "In this case, if the node derived from X3DViewpointNode is not
> >
> > > > > found,
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > no action occurs on activation."
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > This seems to mean that back-up #viewpoint urls should not be
> >
> > > > > tried so
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > that no action can occur. Would that make the most sense ?
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > I actually cannot think of a use case for back-up #viewpoint
> > > > > urls,
> >
> > > > > so
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > that case may be intentionally left ill defined and open to
> >
> > > > > browser
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > implementations.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Any feedback welcome,
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Andreas
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > On Tue, Apr 19, 2022 at 9:34 PM Andreas Plesch
> >
> > <andreasplesch at gmail.com> wrote:
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > x3dom currently lacks support for back-up urls to use if the
> >
> > > > > > first
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > urls do not work. I am trying to add support and wonder how to
> >
> > > > > > deal
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > with corner cases.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > The spirit of the spec. here is pretty clear:
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > https://www.web3d.org/documents/specifications/19775-1/V3.3/Pa
> > > > > > rt
> >
> > > > > > 01/components/networking.html#X3DUrlObject
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > says that a url which cannot be located or if the retrieved
> > > > > > data
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > cannot be All url fields can hold multiple string values. The
> >
> > > > > > strings in these fields indicate multiple locations to search
> >
> > > > > > for data in the order listed. If the browser cannot locate or
> >
> > > > > > interpret the data specified by the first location, it shall
> > > > > > try
> >
> > > > > > the second and subsequent locations in order until a location
> >
> > > > > > containing interpretable data is encountered. X3D browsers
> > > > > > only
> >
> > > > > > have to interpret a single string. If no interpretable
> > > > > > locations
> >
> > > > > > are found, the node type defines the resultant default
> >
> > > > > > behaviour.interpreted should be skipped. Subsequent urls are
> >
> > > > > > then used
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > as back-ups.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > Currently, x3dom checks if an inline x3d url can be parsed as
> >
> > > > > > xml and
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > if so if it has a Scene element.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > The first corner case happens if there is a X3D element but it
> >
> > > > > > does
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > not contain a Scene element. This could be interpreted to mean
> >
> > > > > > an
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > empty X3D document with an empty Scene, or that it perhaps
> >
> > > > > > should be
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > skipped as not interpretable. I would probably favor skipping
> > > > > > as
> >
> > > > > > this
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > would normally happen by mistake.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > The second corner case is a Scene element without content.
> >
> > > > > > Should such
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > X3D be considered interpretable ?  I think x3dom is currently
> >
> > > > > > set up
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > to parse it without error resulting in an empty Scene,
> > > > > > probably
> >
> > > > > > with
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > default NavigationInfo and Viewpoint. So this could be
> >
> > > > > > considered
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > interpretable and not be skipped.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > https://www.web3d.org/x3d/content/examples/X3dSceneAuthoringHi
> > > > > > nt
> >
> > > > > > s.html#urls
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > says a result needs to be "legal". But legal is by definition
> >
> > > > > > what is
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > provided in the spec., eg. comes down to being interpretable.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > The tooltip at
> >
> > > > > > https://www.web3d.org/x3d/content/X3dTooltips.html#Inline.url
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > does not seem to further clarify.
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > Any feedback appreciated,
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > Andreas
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > --
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > Andreas Plesch
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > > Waltham, MA 02453
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > --
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Andreas Plesch
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > Waltham, MA 02453
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > _______________________________________________
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > x3d-public mailing list
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > x3d-public at web3d.org
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > > http://web3d.org/mailman/listinfo/x3d-public_web3d.org
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > >
> >
> > > > --
> >
> > > >
> >
> > > > Andreas Plesch
> >
> > > >
> >
> > > > Waltham, MA 02453
> >
> > > >
> >
> > > >
> >
> > >
> >
> > >
> >
> > >
> >
> > > --
> >
> > > Andreas Plesch
> >
> > > Waltham, MA 02453
> >
> >
> >
> >
> >
> >
> >
> > --
> >
> > Andreas Plesch
> >
> > Waltham, MA 02453
> >
> >
> >
> > _______________________________________________
> >
> > x3d-public mailing list
> >
> > x3d-public at web3d.org
> >
> > http://web3d.org/mailman/listinfo/x3d-public_web3d.org
> >
> >
>
>
>
> --
> Andreas Plesch
> Waltham, MA 02453

--
Andreas Plesch
Waltham, MA 02453