[x3d-public] Request for X3D encoding comment output from X3DPSAIL

[John Carlson]

My current plan for replacing multiple line comments with single lines
comments where the comment content are preserved on separate lines is as
follows:

1.  Write a Java SAX parser to replace newlines with —>\n<!— inside XML
comments.

2.  Compile with GraalVM native-image into rnl.exe, if not taken.

Write a script to apply to all original .x3d files in my examples.  This
will call vim or ex (vim command-line), with the command, %!rnl.exe, then
save and exit.

If needed, I will include carriage return.

Others would try to make this a stylesheet, but I don’t know if comment()
can be split on newlines in XSLT.   So I’ll ask claude.ai again!

<xsl:stylesheet version="2.0" xmlns:xsl="
http://www.w3.org/1999/XSL/Transform">

<xsl:template match="@*|node()">
<xsl:copy>
<xsl:apply-templates select="@*|node()"/>
</xsl:copy>
</xsl:template>

<xsl:template match="comment()">
<xsl:for-each select="tokenize(., '&#xA;')">
<xsl:if test="normalize-space(.) != ''">
<xsl:comment><xsl:value-of select="normalize-space(.)"/></xsl:comment>
</xsl:if>
</xsl:for-each>
</xsl:template>

</xsl:stylesheet>

Gobbledegook to me, but maybe someone can use it.

John

On Sun, Jan 4, 2026 at 3:32 PM John Carlson <yottzumm at gmail.com> wrote:

> For example, it nearly requires program to do this in Python or Perl.
>
> Claude.ai reports:
>
> perl -i -0pe 's/<!--(.*?)-->/join("\n", map {"<!-- $_ -->"} grep
> {s|^\s*||; s|\s*$||; $_} split("\n", $1))/gse' file.xml
>
> Obviously I can put this in a shell script, but I like stuff I can
> understand!
>
> Something in Java would be great!  Maybe I’ll write and contribute if it
> doesn’t already exist?
>
> Seems like a simple SAX parser, frankly!
>
> John
>
> On Sun, Jan 4, 2026 at 3:10 PM John Carlson <yottzumm at gmail.com> wrote:
>
>> Thanks, it wasn’t clear to me that multi-line comments were not supported
>> in X3D XML encoding.  That clears up most of my questions!
>>
>> I will replace multi-line comments with single-line comments in my
>> examples.   Does X3D-Edit support this feature?  This would be great, and
>> encourage me to use it!
>>
>> John
>>
>> On Sun, Jan 4, 2026 at 2:46 PM Don Brutzman <don.brutzman at gmail.com>
>> wrote:
>>
>>> For clarity, here is a recap of key points that can be found in prior
>>> responses and ticket issues:
>>>
>>>    - Persistent single-line comments are an important feature for X3D
>>>    model conversions and interoperability.
>>>    - You are welcome to use all Python features, including multi-line
>>>    comments, whenever programming with Python and x3d.py.
>>>    - Individual multi-line comments are not supported in a number of
>>>    file encodings and programming languages.  Nor are they defined by X3D
>>>    Architecture, nor are they supported by several X3D encodings (such as XML
>>>    and ClassicVRML).  Thus multi-line comments are not a required feature.
>>>    - Persistent comments in x3d.py Python are already supported via a
>>>    Comment class.
>>>    - Persistent single-line comments are now partially supported by
>>>    X3dToPython.xslt converter, if present as children of Scene head and
>>>    grouping nodes.  Further future work on content-model representations in
>>>    the Python class hierarchy may be able to add them elsewhere (e.g. inside
>>>    Shape Appearance Material geometry etc.
>>>    - Tickets are closed after careful review if they are unrepeatable
>>>    or unactionable.  Suggestions and questions about a clearer ticket are
>>>    usually included.
>>>
>>> Hope this helps.
>>>
>>> all the best, Don
>>> --
>>> X3D Graphics, Maritime Robotics, Distributed Simulation
>>> Relative Motion Consulting  https://RelativeMotion.info
>>>
>>>
>>> On Sun, Jan 4, 2026 at 5:57 AM John Carlson <yottzumm at gmail.com> wrote:
>>>
>>>> Blowing off some steam.  Apologies, I probably should work out instead.
>>>>
>>>> I am unsure if it’s easier to output straight line code instead of
>>>> hierarchical code in Python; multi-line non-persistent comments might
>>>> become easier in straight line code.  I don’t know about comments() in
>>>> XSLT.  In straight line code, wrapping a multi or single line comment in
>>>> “””…””” is a cinch.  Even if newlines need to be added for the Python
>>>> interpreter.
>>>> AFAIK, I’ve already mentioned that straight line code is easier to debug,
>>>> in my mind.  I think the Java large file discussion is still open; I
>>>> know hierarchical code is more succinct, and less likely to stack
>>>> overflow.  I think the choices between code structure in Python and Java
>>>> might be different.
>>>>
>>>> Persistent multi-line comments are desirable, even if they aren’t
>>>> present in the archive.  We will probably make different choices between
>>>> hierarchical and straight line code when this feature is available.
>>>>
>>>> Short term hacks like single line comments work until features are
>>>> introduced.  That doesn’t mean tickets should be closed prematurely, or
>>>> examples outside the archives are invalid.
>>>>
>>>> John
>>>>
>>>> On Tue, Dec 30, 2025 at 3:42 AM John Carlson <yottzumm at gmail.com>
>>>> wrote:
>>>>
>>>>> Don, thanks for your comment on this ticket that naively adding
>>>>> Comment to a children field might not work.  That was one of my intentions
>>>>> on expressing myself so vocally.  I apologize for using your time to do
>>>>> this, but I think it revealed a possible design consideration.  I think if
>>>>> I had discovered it, it would have gone over like a wet balloon.
>>>>>
>>>>> Thank you again, I will not put comments arbitrarily in the scenegraph
>>>>> for now with my PythonSerializer.js, until you indicate it’s ready!   I
>>>>> will leave them out of the scenegraph, as they are now.   Since I handle
>>>>> comments generically, I will have to research the nodes you’ve accomplished.
>>>>>
>>>>> Now, can we have other multi-line comments, not in the persistent
>>>>> scenegraph, in Python translated from .x3d, in the short term, like:
>>>>>
>>>>> #
>>>>> # This is comment line 2
>>>>> # This is comment line 3
>>>>> #
>>>>>
>>>>> ?
>>>>>
>>>>> John
>>>>>
>>>>> From the ticket:
>>>>>
>>>>> “
>>>>>
>>>>> This is not an easy fix for converting files because Comment is not
>>>>> part of the content model for all nodes. Solving this will probably require
>>>>> extending class _ X3DNode in x3d.py and sorting out possible subclass
>>>>> collisions. It will also be difficult to retain the original order of child
>>>>> nodes and child comments within a parent node.
>>>>>
>>>>> This might be fixable someday - after some effort I got it working for
>>>>> head, Scene, field, fieldValue.. Deferred as future work.
>>>>>  ”
>>>>>
>>>>> On Mon, Dec 29, 2025 at 12:52 PM Don Brutzman <don.brutzman at gmail.com>
>>>>> wrote:
>>>>>
>>>>>>
>>>>>> I have posted a new ticket to capture this point.  Perhaps a useful
>>>>>> exemplar, as well.
>>>>>>
>>>>>>    - X3D SourceForge ticket #82 creating persistent comments in
>>>>>>    python when converting from XML
>>>>>>    - https://sourceforge.net/p/x3d/tickets/82/
>>>>>>
>>>>>> Hope this helps.  Again thanks for your many efforts.  Have fun
>>>>>> improving X3D!  🤔 👍
>>>>>>
>>>>>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://web3d.org/pipermail/x3d-public_web3d.org/attachments/20260104/c4222413/attachment-0001.html>