[x3d-public] DOM2JSONSerializer.js (and X3DJSONLD.js)

[Andreas Plesch]

Hm, I do not see it.

http://www.web3d.org/specifications/X3dJsonSchemaDocumentation3.3/x3d-3.3-JSONSchema_MetadataSet.html

There does not seem to be a need to link the child as a value
explicitly back to a parent field since the values are already part of
a key/property-value pair ?

-Andreas




On Tue, Mar 6, 2018 at 12:24 PM, John Carlson <yottzumm at gmail.com> wrote:
> It's not that JSON doesn't have container fields.   It's just that they're
> probably called field labels and start with a -.
>
> John
>
> On Mar 6, 2018 12:09 PM, "Andreas Plesch" <andreasplesch at gmail.com> wrote:
>>
>> On Tue, Mar 6, 2018 at 10:46 AM, Andreas Plesch <andreasplesch at gmail.com>
>> wrote:
>> > On Mon, Mar 5, 2018 at 5:25 PM, John Carlson <yottzumm at gmail.com> wrote:
>> >> I have at least one more task on DOM2JSONSerializer.js.  I need to
>> >> identify
>> >> ...
>> >> Time for me to think on this.   What cases should containerField get
>> >> filled
>> >> in in the DOM?  I have been trying to minimize them, but it shot me in
>> >> the
>> >> foot, so now I’m tending to maximize it.
>> >
>> > Here is what I understand about containerfield, probably incompletely:
>> >
>> > From looking at the JSON schema, it appears that json encoding does
>> > not need a containerfield property for any node.
>> > This means that it is generally impossible to have an exact roundtrip
>> > XML/DOM-JSON-XML/DOM if XML/DOM has unnecessary containerfield
>> > attributes since those will not be preserved in the json structure.
>> > It is possible to have functional roundtrips, however.
>> >
>> > For JSON -> XML/DOM it should be ok to just always provide a
>> > containerfield. It may slow down DOM parsing in some X3D browsers, and
>> > leads to verbose XML when serialized.
>> > Perhaps the only comprehensive way to then omit unnecessary
>> > containerfield atttributes is to use the XML schema to assemble a list
>> > of default containerfield values for each x3d node which would take
>> > some time to learn how to do but is a one time effort. x_ite has a
>> > .getContainerField() method for each node which returns the default
>> > containerField.
>> > It should also be possible to generate the limited set of nodes which
>> > can have children which potentially need containerField, or the set of
>> > nodes which never need containerfield in their children. Perhaps such
>> > a list already exists ?
>>
>> Digging found this list of nodes:
>>
>>
>> http://www.web3d.org/x3d/content/examples/X3dSceneAuthoringHints.html#containerField
>>
>> which is what I had in mind.
>>
>> I think grouping nodes may also need to be listed since their xml
>> children may either be values of their children field (the default) or
>> the value of their SFNode metadata field.
>>
>> -Andreas
>>
>>
>> >
>> > -Andreas
>> >
>> >
>> >
>> >>
>> >>
>> >>
>> >> John
>> >>
>> >>
>> >>
>> >> Sent from Mail for Windows 10
>> >>
>> >>
>> >>
>> >> From: John Carlson
>> >> Sent: Monday, March 5, 2018 1:22 PM
>> >> To: Andreas Plesch
>> >> Cc: Holger Seelig; X3D Graphics public mailing list; Don Brutzman
>> >> Subject: Re: Effects of scrunching all VRMLscript in a Script into a
>> >> singleline, X_ITE.
>> >>
>> >>
>> >>
>> >> Thanks for your explanation, Andreas.  It looks like I should proceed
>> >> with
>> >> good speed at coming up with a replacement for X3dToJson.xslt.    which
>> >> is
>> >> almost complete, if someone wants to help...
>> >>
>> >>
>> >>
>> >>
>> >> https://github.com/coderextreme/X3DJSONLD/blob/master/src/main/node/DOM2JSONSerializer.js
>> >>
>> >>
>> >>
>> >> One of the last tasks is identifying which arrays should be objects.
>> >>
>> >>
>> >>
>> >> John
>> >>
>> >>
>> >>
>> >> On Mar 5, 2018 12:57 PM, "Andreas Plesch" <andreasplesch at gmail.com>
>> >> wrote:
>> >>
>> >> One (fatal) issue with just merging all lines into a single line are
>> >> caused by ecmascript single line comments:
>> >>
>> >> // helpful explanation
>> >> var radius1 = outerRadius - toothDepth / 2;
>> >> ...
>> >>
>> >> versus
>> >>
>> >> // helpful explanation var radius1 = outerRadius - toothDepth / 2; ...
>> >>
>> >> which never evaluates radius1.
>> >>
>> >> If all comments would be replaced by multiline commenting  as in /*
>> >> helpful explanation */ , the single script line may work (if all lines
>> >> are carefully terminated by semicolons which is not required in many
>> >> situations in ecmascript:
>> >>
>> >> https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#Automatic_semicolon_insertion
>> >> ,
>> >>
>> >> https://www.theregister.co.uk/2018/01/12/javascript_technical_group_semicolons/).
>> >>
>> >> It is definitely safest (and probably unavoidable) to preserve line
>> >> breaks in the json.
>> >>
>> >> X_ITE itself cannot really do much more than eval the provided script
>> >> as is.
>> >>
>> >> -Andreas
>> >>
>> >>
>> >>
>> >>
>> >> On Mon, Mar 5, 2018 at 11:23 AM, John Carlson <yottzumm at gmail.com>
>> >> wrote:
>> >>> Holger, can you look at X_ITE to see the effect of scrunching all the
>> >>> VRMLScript in a Script into a single line?  I’m having issues with
>> >>> that
>> >>> right now, with JSON.  Thanks!
>> >>>
>> >>>
>> >>>
>> >>> John
>> >>
>> >>
>> >>
>> >> --
>> >> Andreas Plesch
>> >> Waltham, MA 02453
>> >>
>> >>
>> >
>> >
>> >
>> > --
>> > Andreas Plesch
>> > Waltham, MA 02453
>>
>>
>>
>> --
>> Andreas Plesch
>> Waltham, MA 02453



-- 
Andreas Plesch
Waltham, MA 02453