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 Workshop: A new icon for linked paragraphs
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In sources books with translation it might come in handy to have the text of the original and a translation linked together. The book might be so constructed that there is first the original part, a transcription, and after that a translation with additional comments and footnotes. In that case, this is more than a side by side layout, but something that is two parts of consecutive text, but with references to each other.

Situation
=========

The print version
-----------------

For the print version the decision was made to have a chapter-to-chapter link instead of linking to the paragraphs, so a text was inserted after the heading that points to the parallel chapter.

Since the original source keeps all the information of linking from paragraph to paragraph, the online version should profit from that.

Starting at the end
-------------------

Looking at the publication platform, it was rather obvious that an icon margin could be used for that purpose: If a paragraph was linked to another, an icon beside it would notify the reader, and if he clicked on it, a popup, similar to those of the bookmark icons, would provide a link to the parallel part.

On the side of the publication platform it would require the following changes:

- adding an icon to the webdesign
- extending the javascript to provide functionality
- adding a rule to the template to display the icon
- extending the model for a field for the link

Looking at the beginning
------------------------

TEI
~~~

Looking at the source text and its conversions the question was what scripts were to be extended to include the functionality. In the TEI source, the paragraphs were equipped with ``@corresp`` and ``@xml:id`` attributes, required for the linking. Through the various steps (``tei2imxml``, ``imxml2django``), these attributes were retained. So the functionality could be inserted into the last step, ``imxml2django``. The ``@corresp`` attribute was resolved to an ``@href`` attribute with a concrete link that would work on the platform (by linking to chapter and paragraph).

EOATeX
~~~~~~

This feature was also implemented for the EOATeX track. A new command was added to the `pre_xml.tex`::

   % \EOApararef{id=hypertarget}{corresp=hyperlink}
   \newcommand*{\EOApararef}[2]{
     \begin{xmlelement}{EOApararef}\end{xmlelement}
     \AddAttToLast{xml:id}{#1}
     \AddAttToLast{corresp}{\##2}
     }

Which creates a new element whose attributes are written to the parent paragraph tag in the postprocessing in `eoatex2imxml`.

Meeting in the middle
---------------------

Finally, the publication import script would need to pick up the ``@href`` and write it into the new field in the model.


Extending the webdesign
-----------------------

The webdesign can easily be modified to feature new icons in the sidebar. An icon needs to be created, as well as added functionality in the javascript and instructions in the css file.


Implementation
==============

Changes in the EOATeX XML preambel: https://github.molgen.mpg.de/EditionOpenAccess/eoa-publication-model/commit/6e69515b6399d8dc045c05b670c18f991144c360

Changes in EOASkripts

- ``imxml2django``: https://github.molgen.mpg.de/EditionOpenAccess/EOASkripts/commit/09ddd5218ce11e1963ee96fa837bd0f60e2d1075
- ``eoatex2imxml``: https://github.molgen.mpg.de/EditionOpenAccess/EOASkripts/commit/84b7026e354d035be2062f83f338c145bc8ad6d3

Changes in ``django-eoapublications`` are collected in this commit: https://github.molgen.mpg.de/EditionOpenAccess/django-eoapublications/commit/030e6f2bac1b7413fd4d5c2baeebd6871cd639a3

The webdesign requires some changes that are collected in this commit: https://github.molgen.mpg.de/EditionOpenAccess/webdesign_platform/commit/c995a9e38a67efecd2831c558ea279d6396d7d00