[x3d-public] JSON Script encoding [was announce: updated encoding, X3D to JSON Stylesheet Converter: string arrays, whitespace, UTF-8, Script #source]
Leonard Daly
web3d at realism.com
Fri Nov 20 07:07:18 PST 2015
I think trying to figure out the encoding of a Script node is getting a
little ahead of things.
JSON code is typically executed to create the data structure(s). In this
case it appears that the result will be to put the script code into a
variable that needs to be executed again. Unless JSON is to be used as
another encoding for storage and transport, I think the use within HTML
needs to be settled first.
Leonard Daly
> The 3-way option for Script #source is now deployed in the examples,
> described on the X3dToJson stylesheet page, and implemented in
> X3D-Edit to facilitate testing. Conversion parameters panel
> screenshot attached.
>
> http://www.web3d.org/x3d/stylesheets/X3dToJson.html#Options
> https://savage.nps.edu/X3D-Edit/#new
> https://savage.nps.edu/X3D-Edit/images/X3dToJsonConversionPanel.png
>
> On 11/18/2015 4:43 PM, Don Brutzman wrote:
>> OK and now for the next level for Script source code in JSON form...
>>
>> "When you come to a fork in the road, take it." Yogi Berra
>>
>> John: let's make the #source content a string array, and then
>> authors/tools/files can use any of the three forms equivalently.
>> first 2 out of 3 pass jslint, likely 3 out of 3 just plain work.
>>
>> as before, but in consistent ["string-array"] form:
>>
>> - array of one plaintext block string.
>> - array of one single-line string with all linefeeds and tabs escaped
>> as \n and \t.
>> - array of multiple one-line strings as shown below.
>>
>> A commonly acceptable solution for each of the alternatives takes all
>> the sting out of any choice, we don't have to worry about tradeoff
>> advantages/disadvantages.
>>
>> Pretty exciting that a no-lose approach might exist to cope with this
>> situation! 8)
>>
>> So I will change stylesheet support for the three alternatives to all
>> be string _array_ and rebuild the examples.
>>
>> I hope this fine tuning doesn't interrupt your loader efforts.
>>
>> p.s. cosmetic: maybe we should rename #source to #sourceText or
>> somesuch - a more descriptive key name might also be preferable.
>>
>>
>> On 11/17/2015 10:17 PM, Don Brutzman wrote:
>>> [summary: from plaintext block to total escapism and now to string
>>> array for #source block]
>>>
>>> On 11/17/2015 7:21 AM, John Carlson wrote:
>>>> Why isn't an array of strings acceptable?
>>>
>>> On 11/17/2015 7:23 AM, John Carlson wrote:
>>>> It's a typical javascript pattern to create arrays of strings and
>>>> then join them.
>>>
>>> glad to hear it!
>>>
>>> If arrays of json strings are typical and acceptable and not an
>>> undue complication for plain old javascript programmers, then it is
>>> certainly fine with me. I strongly believe that human readability
>>> is important. Quoted strings are surely better than garble.
>>>
>>> It is no trouble for me to export .x3d to .json #source that way as
>>> well. I have added another option to the stylesheet switch tonight
>>> to produce that alternative.
>>>
>>> Example attached, excerpt follows. Hmmm, not too bad, and certainly
>>> not confusable.
>>>
>>> I will again regenerate all examples in that form if opinions are
>>> leaning that way.
>>>
>>> ==========================================
>>> "-children":[
>>> { "Script":
>>> [...snip...]
>>> "#source":[
>>> "ecmascript:",
>>> "function initialize ()",
>>> "{",
>>> " checkCoordinatePoints ();",
>>> "}",
>>> "function checkCoordinatePoints ()",
>>> "{",
>>> " // A parallelepiped has three sets of four parallel edges; the
>>> edges within each set are of equal length.",
>>> " // Quality assurance: check that lengths of corresponding sides
>>> match.",
>>> " ",
>>> " edge01 = length2(point[0], point[1]); // top",
>>> " edge12 = length2(point[1], point[2]);",
>>> " edge23 = length2(point[2], point[3]);",
>>> " edge30 = length2(point[3], point[0]);",
>>> " edge45 = length2(point[4], point[5]); // bottom",
>>> " edge56 = length2(point[5], point[6]);",
>>> " edge67 = length2(point[6], point[7]);",
>>> " edge74 = length2(point[7], point[4]);",
>>> " edge04 = length2(point[0], point[4]); // sides",
>>> " edge15 = length2(point[1], point[5]);",
>>> " edge26 = length2(point[2], point[6]);",
>>> " edge37 = length2(point[3], point[7]);",
>>> " ",
>>> " epsilon = edge01 * 0.001;",
>>> " ",
>>> " if ((Math.abs(edge01 - edge23) > epsilon) ||",
>>> " (Math.abs(edge23 - edge67) > epsilon) ||",
>>> " (Math.abs(edge67 - edge45) > epsilon) ||",
>>> " (Math.abs(edge45 - edge01) > epsilon))",
>>> " Browser.println ('Warning, mismatched parallelopiped sides
>>> 02/33/45/67');",
>>> " else if ((Math.abs(edge30 - edge12) > epsilon) ||",
>>> " (Math.abs(edge12 - edge56) > epsilon) ||",
>>> " (Math.abs(edge56 - edge74) > epsilon) ||",
>>> " (Math.abs(edge74 - edge30) > epsilon))",
>>> " Browser.println ('Warning, mismatched parallelopiped sides
>>> 30/12/56/74');",
>>> " else if ((Math.abs(edge04 - edge15) > epsilon) ||",
>>> " (Math.abs(edge15 - edge26) > epsilon) ||",
>>> " (Math.abs(edge26 - edge37) > epsilon) ||",
>>> " (Math.abs(edge37 - edge04) > epsilon))",
>>> " Browser.println ('Warning, mismatched parallelopiped sides
>>> 04/15/26/37');",
>>> "}",
>>> "function length2 (pointA, pointB)",
>>> "{ ",
>>> " return Math.sqrt((pointA.x - pointB.x)*(pointA.x - pointB.x) +",
>>> " (pointA.y - pointB.y)*(pointA.y - pointB.y) +",
>>> " (pointA.z - pointB.z)*(pointA.z - pointB.z));",
>>> "}",
>>> "function set_point (eventValue)",
>>> "{",
>>> " // input eventValue received for inputOutput field",
>>> " point = eventValue;",
>>> " checkCoordinatePoints ();",
>>> "}"
>>> ]
>>> }
>>> }
>>> ]
>>> ==========================================
>>>
>>> Example reassembly to join strings back together in javascript:
>>>
>>> http://stackoverflow.com/questions/2392766/multiline-strings-in-json
>>>> Once parsed, I just use myData.modify_head.join('\n') or
>>>> myData.modify_head.join(),
>>>> depending upon whether I want a line break after each string or not.
>>>
>>> Wondering, what would that join() code specifically look like for an
>>> X3D JSON loader?
>>>
>>> Looking forward: seems like a group/community decision if we want to
>>> specify a string array as X3D JSON default for #source blocks.
>
> all the best, Don
>
>
> _______________________________________________
> x3d-public mailing list
> x3d-public at web3d.org
> http://web3d.org/mailman/listinfo/x3d-public_web3d.org
--
*Leonard Daly*
X3D Co-Chair
Cloud Consultant
President, Daly Realism - /Creating the Future/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://web3d.org/pipermail/x3d-public_web3d.org/attachments/20151120/6149dea2/attachment-0001.html>
More information about the x3d-public
mailing list