[tei-council] [TEI-DIR-WG] Outcome of TEI Council discussion on Text Directionality

[Kevin Hawkins]

I hereby offer my general approval of the idea!  --Kevin

On 9/6/2013 12:37 PM, Martin Holmes wrote:
> Hi everyone,
>
> This message is going both to the TEI Council and to the Text
> Directionality Working Group.
>
> Following the discussion below in April and my presentation at the TEI
> Council meeting, nothing has happened partly because I've been very
> busy, but partly because I've been waiting for changes in the CSS
> Writing Modes specification to settle down a bit, and for an answer to
> the question of why bottom-to-top writing modes are not included in CSS
> Writing Modes. I haven't had any luck with the latter so far, although
> I'm waiting for a message to the W3C Style mailing list on the topic to
> be approved.
>
> Meanwhile, I've been revisiting the proposal for new @rotate*
> attributes, and I wonder if there might be a better solution in CSS
> Transforms:
>
> <http://www.w3.org/TR/css3-transforms/>
>
> There are a number of reasons why I think this is a better approach:
>
> 1. It's an existing standard. Using an existing standard is always
> better than rolling your own, especially when we have already bought
> into CSS in the directionality part of the equation.
>
> 2. It's much richer than what we could achieve with our rotation
> attributes; in addition to simple 2D and 3D rotation, it allows (for
> instance) translation (moving an element relative to its base position),
> skewing, rotation around different origin points, and many other useful
> features.
>
> 3. It doesn't involve creation of any new attributes in TEI, so there's
> no need for argument about what elements should carry them.
>
> 4. User agents already have some support for 2D transforms and that
> support will increase over time. Where documents are being rendered in
> web browsers, it will be simpler for rendering pipelines to pass through
> CSS code where appropriate than to generate it based on TEI attributes.
> (This is a pragmatic point rather than a point of principle, of course.)
>
> If we do recommend an approach to layout description based on CSS
> Transforms rather than on new TEI attributes, we'll be presenting a
> unified approach to the two separate but related problems (true text
> directionality and rotational features).
>
> I'd be grateful to get feedback on this. If there's general approval for
> the idea, I'll update the workgroup Wiki page and the ticket:
>
> <http://wiki.tei-c.org/index.php/Text_Directionality_Workgroup>
> <https://sourceforge.net/p/tei/feature-requests/342/>
>
> Cheers,
> Martin
>
> On 13-04-26 01:17 PM, Martin Holmes wrote:
>> Doh!
>>
>> SHOULD BE:
>>
>> The existing one is for rotate-z, so we could say that where there is a
>> single value, it applies to the z axis, and where there are multiple
>> values, they are x, y, z (two values would presumably not be allowed).
>>
>> Cheers,
>> Martin
>>
>> On 13-04-26 12:48 PM, Martin Holmes wrote:
>>> HI Marcus,
>>>
>>> I'm replying to this through the mailing list, so that it gets archived
>>> appropriately.
>>>
>>> I really like your idea of a single @rotate (rather than @rotation) with
>>> three values, especially because it holds out the promise of
>>> backward-compatibility with the existing @rotate attribute. The existing
>>> one is for rotate-x, so we could say that where there is a single value,
>>> it applies to the x axis, and where there are multiple values, they are
>>> x, y, z (two values would presumably not be allowed). This would be even
>>> more perfect if the current @rotate were x (the first of the three), but
>>> I guess we can't have everything.
>>>
>>> On the other hand, if we create a new @rotation attribute, we can do
>>> what we like with it, and perhaps deprecate the old @rotate after a
>>> specified length of time.
>>>
>>> Regarding bottom-to-top, I appreciate the simplicity of going with pure
>>> CSS for the moment, but I would like to find out why it's not in there,
>>> and if there are plans to add it. If there's a principled objection to
>>> it, we might well want to suggest alternatives.
>>>
>>> Cheers,
>>> Martin
>>>
>>> On 13-04-26 11:51 AM, Marcus Bingenheimer wrote:
>>>> Dear Martin,
>>>>
>>>> Thanks for that clear presentation and summary. I think we can be
>>>> satisfied
>>>> with the outcome.
>>>>
>>>> 1. As for the bottom-to-top issue I want to argue the following:
>>>> CSS is likely to include bottom-to-top writing at one point, if not for
>>>> Batak, Hanuno'o and Ancient Berber, then for the sheer ornamental
>>>> purposes.
>>>> This might come in tandem with a solution for writing along paths /
>>>> Bézier curves.
>>>> Instead of adding complexity to our recommendation we might be better
>>>> off
>>>> admitting incompleteness. In case someone is working on one of the
>>>> extremely rare bottom-top scripts in TEI, the writing direction and its
>>>> implementation is going to be a major issue in any case and has to be
>>>> addressed specifically, probably somewhere in the header. I suggest
>>>> we do
>>>> not offer additional functionality for bottom-top, which might become
>>>> obsolete as CSS evolves, but rather say @style should follow CSS to its
>>>> present capabilities and recommend to record information on writing
>>>> systems
>>>> and direction that goes beyond that in the header for now.
>>>>
>>>>
>>>> 2. Regarding the scoping of the @rotation-x-y-z:
>>>> I am for the most "liberal" scoping as I want to rotate not only inline
>>>> text but also images.
>>>> By the way, have we considered to have only one @rotation which takes
>>>> three
>>>> values (x, y, z)? Something like @rotation="0 180 0" (180 along
>>>> y), @rotation="50 0 90" (50 along x and 90 along z)
>>>>
>>>> all the best
>>>>
>>>> marcus
>>>>
>>>> On Thu, Apr 25, 2013 at 12:26 PM, Martin Holmes<mholmes at uvic.ca>  wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>> This is a joint message to the TEI Council list and to the Text
>>>>> Directionality Working Group list.
>>>>>
>>>>> We had a TEI Council meeting in Providence a couple of weeks ago, and I
>>>>> made a presentation on the work we've done so far on text
>>>>> directionality.
>>>>> The slides of the presentation are here:
>>>>>
>>>>> <http://wiki.tei-c.org/images/**4/48/Text_directionality.pdf<http://wiki.tei-c.org/images/4/48/Text_directionality.pdf>
>>>>>
>>>>>
>>>>>>
>>>>>
>>>>> and the minutes from the Council meeting are here:
>>>>>
>>>>> <http://www.tei-c.org/**Activities/Council/Meetings/**
>>>>> tcm54.xml#body.1_div.1_div.3_**div.1<http://www.tei-c.org/Activities/Council/Meetings/tcm54.xml#body.1_div.1_div.3_div.1>
>>>>>
>>>>>
>>>>>>
>>>>>
>>>>> At the meeting, I made the following three proposals:
>>>>>
>>>>> 1. That we ignore Unicode for the moment, mainly because it's not
>>>>> relevant
>>>>> for us (UTR #20 Unicode in XML and other Markup Languages
>>>>> advises that bidi embedding (and presumably isolate) control characters
>>>>> NOT be used in XML markup), and because it's moving VERY slowly on
>>>>> vertical
>>>>> orientation anyway (recent UTR #50 revisions have considerably
>>>>> reduced its
>>>>> scope in this regard).
>>>>>
>>>>> 2. That we formally adopt CSS Writing Modes, and provide examples of
>>>>> how
>>>>> to use it through the @style attribute.
>>>>>
>>>>> 3. That we create @rotate-x, @rotate-y and @rotate-z attributes to
>>>>> capture
>>>>> all manner of rotation (which can also help to handle edge-cases of
>>>>> directionality such as boustrophedon).
>>>>>
>>>>> There was a generally favourable reaction to all three proposals, and I
>>>>> was tasked with summarizing them to the Council list and to the working
>>>>> group, which I'm now doing.
>>>>>
>>>>> These were some issues that Council would like to see addressed:
>>>>>
>>>>> 1. CSS WRITING MODES AND BOTTOM-TO-TOP SCRIPTS:
>>>>>
>>>>> It's notable that the CSS Writing Modes draft explicitly excludes
>>>>> bottom-to-top vertical text: "Inherently bottom-to-top scripts are not
>>>>> handled in this version. See [UTN22] for an explanation of relevant
>>>>> issues." I personally don't see anything in UTN22 that justifies this
>>>>> exclusion, and indeed very recent changes to CSS Writing Modes seem
>>>>> to be
>>>>> designed to fudge some accommodation for bottom-to-top into the system:
>>>>> "The ‘sideways-left’, ‘sideways-right’, and ‘sideways’ values of
>>>>> ‘text-orientation’ are provided for decorative layout effects and to
>>>>> work
>>>>> around limitations in CSS support for bottom-to-top scripts."
>>>>>
>>>>> Council asked me to contact the W3C working group and clarify the
>>>>> exclusion of bottom-to-top scripts. Before I do that, I've been
>>>>> trying to
>>>>> figure out if there's any existing discussion of it on their public
>>>>> discussion list:
>>>>> <http://lists.w3.org/Archives/**Public/www-style/<http://lists.w3.org/Archives/Public/www-style/>>.
>>>>>
>>>>>
>>>>> I'd appreciate any help with this that you have time to give.
>>>>>
>>>>> If the specification is leaving out bottom-to-top because of the
>>>>> lack of
>>>>> sufficient scripts in Unicode that are oriented that way, then maybe
>>>>> Debbie
>>>>> can let us know whether there are more bottom-to-top scripts on the
>>>>> road
>>>>> for inclusion in Unicode; we might be able to use that as an argument
>>>>> for
>>>>> more robust support for it in CSS Writing Modes.
>>>>>
>>>>> 2. PROPOSAL #3: WHAT ELEMENTS SHOULD HAVE THESE NEW ATTRIBUTES
>>>>>
>>>>> Currently, the TEI @rotate attribute (which really means rotate-z,
>>>>> rotation around the z axis) is available only on<zone>. The three
>>>>> attributes we propose, one of which would replace it, would be
>>>>> provided as
>>>>> a class. The question is what elements should be members of that class.
>>>>>
>>>>>    - The most conservative approach would be to keep it only to
>>>>> <zone>, so
>>>>> you could only use rotation if you're using the Facsimile module.
>>>>>
>>>>>    - Another would be to say that rotational features are inherently
>>>>> topographical, and therefore all suitable elements in the genetic
>>>>> editing
>>>>> set (<line>  etc.) might also bear them.
>>>>>
>>>>>    - Most liberally, we might say that these rotational attributes
>>>>> may be
>>>>> essential in any kind of transcription, so they should be available
>>>>> on any
>>>>> transcription-bearing element in<text>  or<sourceDoc>.
>>>>>
>>>>> I'd be grateful for your feedback on this, and any insights anyone can
>>>>> glean from the W3C style list archives regarding bottom-to-top text.
>>>>>
>>>>> Cheers,
>>>>> Martin
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Martin Holmes
>>>>> University of Victoria Humanities Computing and Media Centre
>>>>> (mholmes at uvic.ca)
>>>>>
>>>>
>>>>
>>>>
>>>
>>
>