Author: Günter Milde
Date: 2014-12-25

# greek-fontenc

## Greek font encoding definition files

Author
  Günter Milde
Date
  2014-12-25
Copyright
  © 2013 Günter Milde <milde@users.sf.net>
Licence

  This work may be distributed and/or modified under the conditions of the LaTeX Project Public License, either version 1.3 of this license or any later version.

Abstract

LaTeX internal character representation (LICR) macros are a verbose but failsafe 7-bit ASCII encoding that works unaltered under both, 8-bit TeX and XeTeX/LuaTeX. Use cases are macro definitions and generated text

This package provides Greek LICR macro definitions and encoding definition files for Greek text font encodings for use with fontenc.

Note

The LICR macro names for Greek symbols are chosen pending endorsement by the TeX community and related packages.

Names for archaic characters, accents/diacritics, and punctuation may change in future versions.

# News

0.9 | 2013-07-03 | greek-fontenc.def “outsourced” from lgrxenc.def
|  | experimental files xunicode-greek.sty and greek-euenc.def: LICRs for XeTeX/LuaTeX.
0.9.1 | 2013-07-18 | Bugfix: wrong breathings psilioxia -> dasiaoxia.
0.9.2 | 2013-07-19 | Bugfix: Disable composite defs starting with char macro,
|  | fix “hiatus” handling.
0.9.3 | 2013-07-24 | Fix “input” path in xunicode-greek and greek-euenc.def.
0.9.4 | 2013-09-10 | greek-fontenc.sty: Greek text font encoding setup package,
|  | remove xunicode-greek.sty.
0.10 | 2013-09-13 | textalpha.sty and alphabeta.sty moved here from lgrx and updated to work with XeTeX/LuaTeX.
|  | greek-fontenc.sty removed (obsoleted by textalpha.sty).
0.10.1 | 2013-10-01 | Bugfix in greek-euenc.def and alphabeta-euenc.def.
0.11 | 2013-11-28 | Compatibility with Xe/LuaTeX in 8-bit mode,
|  | `\greekscript` TextCommand.
0.11.1 | 2013-12-01 | Fix identification of `greek-euenc.def`.
0.11.2 | 2014-09-04 | Documentation update, remove duplicate code.
0.12 | 2014-12-25 | Fix auxiliary macro names in textalpha.
|  | Conservative naming: move definition of `\<` and `\>` from `greek-fontenc.def` to `textalpha.sty` (Bugreport David Kastrup). Documentation update.

# TeX files

greek-fontenc.def

  Common Greek font encoding definitions.

lgrenc.def

  LGR Greek font encoding definitions.

  This file is the successor of the basic LGR encoding definition file which comes with babel’s Greek support and `lgrxenc.def` from the lgrx bundle.

textalpha.sty

  Greek symbols in text independent of font encoding and TeX engine.

alphabeta.sty

  Generic macros for Greek symbols in text and math.

alphabeta-euenc.def

  Composite defintions for alphabeta.sty_ with XeTeX/LuaTeX.

greek-euenc.def

  Greek LICR definitions for XeTeX and LuaTeX. Requires euenc.

Literate source files were converted with PyLit to reStructuredText and with Docutils to the HTML documentation.

# Documentation and test documents

textalpha-doc.tex, textalpha-doc.pdf

  The textalpha package.

alphabeta-doc.tex alphabeta-doc.pdf

  The alphabeta package.

lgrenc-test.tex, lgrenc-test.pdf

  Test and usage example.

greek-euenc-doc.tex, greek-euenc-doc.pdf

  Example for use of the experimental Greek LICR definitions with XeTeX or LuaTeX.

greekhyperref.tex, greekhyperref.pdf

  Greek script in PDF metadata.

  The package hyperref defines the PU font encoding which also supports (monotonic) Greek.

# Experimental files

These files are still in development and will eventually be moved to/merged with other packages or removed in future versions:

lgr2licr.lua

  LGR Transcription to Greek LICR transformation

# Installation

If possible, get this package from your distribution using its installation manager.

Otherwise, make sure LaTeX can find the package and definition files:

- Download and unpack `greek-fontenc.zip`.

- Copy/Move/Link files ending in `.def` or `.sty` to a suitable place in the TDS and run `texhash`, or place them in the current working directory (e.g. for testing).

# Usage

There are many alternatives to use the Greek font encoding setup provided by this package/bundle, e.g.:

- Ensure Greek support in text mode with textalpha:

      \usepackage{textalpha}

  For details see textalpha-doc.tex and textalpha-doc.pdf (8-bit TeX) as well as greek-euenc-doc.tex and greek-euenc-doc.pdf (XeTeX/LuaTeX).

- To use the short macro names (`\alpha` … `\Omega`) known from math mode in both, text and math mode, write

      \usepackage{alphabeta}

  For details see alphabeta-doc.tex and alphabeta-doc.pdf.

- Use the `greek` option with Babel (requires babel-greek):

      \usepackage[greek]{babel}

- Declare LGR via fontenc. For example, specify T1 (8-bit Latin) as default font encoding and LGR for Greek with

      \usepackage[LGR,T1]{fontenc}

  Note that without `textalpha` or `alphabeta`, Greek text macros work only if the current font encoding supports Greek. See [fntguide] for details and lgrenc-test.tex for an example.

- LGR encoded fonts can also be used alongside Unicode fonts with XeTeX/LuaTeX to enable the input of Greek letters via the Latin transcription provided by this font encoding. See greek-euenc-doc.tex -> greek-euenc-doc.pdf and lgrenc-test.tex -> lgrenc-test.pdf.

# Greek text font encodings

Greek TeX font encodings are the envisaged T7, LGR, and LGI. Greek letters and symbols are also defined in the Unicode-based font encodings EU1 (XeTeX), EU2 (LuaTeX) and PU (hyperref).

## T7

The [encguide] reserves the name T7 for a Greek standard font encoding. However, up to now, there is no agreement on an implementation because the restrictions for general text encodings are too severe for typesetting polytonic Greek.

## LGR

The LGR font encoding is the de-facto standard for typesetting Greek with (8-bit) LaTeX. Fonts in this encoding include the CB fonts (matching CM), grtimes (Greek Times), Kerkis (matching URW Bookman), and the GFS font collection. Setup of these fonts as Greek variant to matching Latin fonts is facilitated by the substitutefont package.

The LGR font encoding allows to access Greek characters via an ASCII transliteration. This enables simple input with a Latin keyboard. Characters with diacritics can be selected by ligature definitions in the font (see [greek-usage], [teubner-doc], [cbfonts]).

A major drawback of the transliteration is, that you cannot access Latin letters if LGR is the active font encoding (e.g. in documents or parts of documents given the Babel language `greek` or `polutionikogreek`). This means that for every Latin-written word or acronym an explicit language-switch is required. This problem can only be solved via a font-encoding comprising Latin and Greek like the envisaged T7 or Unicode (with XeTeX or LuaTeX).

## LGI

The ‘Ibycus’ fonts from the package ibygrk implement an alternative transliteration scheme (also explained in [babel-patch]). It is currently not supported by greek-fontenc.

The font encoding file `lgienc.def` from ibycus-babel provides a basic setup (without any LICR macros or composite definitions).

# Greek LICR macro names

This package provides LaTeX internal character representations (LICR macros) for Greek letters and diacritics. Macro names were selected based on the following considerations:

The fntguide (section 6.4 Naming conventions) recommends:

> Where possible, text symbols should be named as `\text` followed by the Adobe glyph name: for example `\textonequarter` or `\textsterling`. Similarly, math symbols should be named as `\math` followed by the glyph name, for example `\mathonequarter` or `\mathsterling`.

The Adobe Glyph List For New Fonts has names for many glyphs in the Greek and Coptic Unicode block, but not for Greek extended. The Adobe Glyph List (for existing fonts) lists additional glyph names used in older fonts. As these are not intened for further active use, the latter are not considered in the name choice.

## Proposals

- If there exists a math-mode macro for a symbol, form the corresponding text macro by prepending `text`?

  Example:

    The glyph name for the GREEK SMALL LETTER FINAL SIGMA is `sigma1`, the corresponding math-macro is `\varsigma`. The text symbol could be made available as `\textvarsigma`.

  Problems:

    `\varepsilon` and `\varphi` math macros map to characters named “GREEK SMALL LETTER …”, while `\\vartheta`, `\\varkappa`, `\\varrho`, and `\\varpi` math macros map to “GREEK … SYMBOL” Unicode characters.

    In Greek text, these variants are interchangeable. The LGR font encoding does not contain slots for “symbol” glyph variants. In some Greek fonts, GREEK SMALL LETTERS use glyph variants resembling the corresponding GREEK SYMBOL Unicode character’s reference glyph.

- Derive macro names from Unicode names?

  The Unicode names list provides standardized descriptive names for all Unicode characters that use only capital letters of the Latin alphabet. While not suited for direct use in a LICR macros, they can be either

  1. used as inspiration for new LICR macro names or

  2. converted to LICR macro names via a defined set of transformation rules.

  Example:

    `\textfinalsigma` or just `\finalsigma` as a more descriptive name for GREEK SMALL LETTER FINAL SIGMA derived via the rules:

    - drop “LETTER” if the name remains unique,

    - drop “GREEK” if the name remains unique,

    - use capitalized name for capital letters, lowercase for “SMALL” letters and drop “SMALL”,

    - concatenate

- Omit the “text” prefix for macros that do not have a math counterpart?

  Pro:

    - Simpler,

    - ease of use (less typing, better readability of source text),

    - many established text macro names without “text”,

    - there are examples of encoding-specific macros without the `text`-prefix, especially for letters,

      T1

        `\AE \DH \DJ \L \NG \OE \O \SS \TH \ae \dh \dj \guillemotleft` `\guillemotright \guilsinglleft \guilsinglright \i \j \l \ng` `\oe \o \quotedblbase \quotesinglbase \ss \th` (also in OT1)

      T2*

        `\CYR*` and `\cyr*`

      HE8

        `\heb*` or no prefix

      PU

        short descriptive names in the arabic part (`puarenc.def`)

    - `text` prefix does not mark a macro as encoding-specific or “inserting a glyph”. There are e.g. font-changing macros (`\textbf`, `\textit`) and encoding-changing macros (`\textgreek`, `\textcyr`).

  Contra:

    - Less consistent.

    - `text` prefix marks a macro as confined to text (as opposed to math) mode.

  Conclusion:

    To avoid name clashes, the font encoding definition files use the `text` prefix for symbols. Aliases (short forms, compatibility defs, etc.) can be defined locally or in additional packages (see alphabeta.sty, babel-greek, or teubner)

## How to name accent macros?

- standard accent macros (`\DeclareTextAccent` definitions in `latex/base/...`) are one-symbol macros (`\' \" ... \u \v ...`) .

- `tipa.sty`, xunicode, and ucs use the “text” prefix also for accents.

  However, the Adobe Glyph List For New Fonts maps, e.g., “tonos” and “dieresistonos” to 0384 GREEK TONOS and 0385 GREEK DIALYTIKA TONOS, hence texttonos and textdiaresistonos should be spacing characters.

- textcomp (ts1enc.def) defines `\capital...` accents (i.e. without `text` prefix).

- Use a common prefix `\textaccent...`, `\accent...`, or just `\acc...` (cf. `\@tabacckludge`)?

Currently, greek-fontenc uses for diacritics:

- Greek names like in Unicode, and ucsencs.def

- The prefix “acc” to distinguish the macros as TextAaccent and reduce the risc of name clashes.

- For the end-user “symbol macros” (`\~ \' \` \" \< \>`) are provided. (The non-standard macros `\<` and `\>` only with textalpha.sty.)

## References

An alternative, more complete set of short mnemonic character names is the XML Entity Definitions for Characters W3C Recommendation from 01 April 2010.

For glyph names of the LGR encoding see e.g. `CB.enc` by Apostolos Syropoulos and `xl-lgr.enc` from the libertine (legacy) package. `lgr.cmap` provides a mapping to Unicode characters.

A full set of `\text*` symbol macros is defined in `ucsencs.def` from the ucs package.

Aliases from `puenc.def` ensure that the hyperref package can convert Greek text in “LICR encoding” to a PDF-string (utf-8 encoded input is used as-is).

[fntguide]

  LaTeX3 Project Team, LaTeX2ε font selection, 2005. http://mirror.ctan.org/macros/latex/doc/fntguide.pdf

[encguide]

  Frank Mittelbach, Robin Fairbairns, Werner Lemberg, LaTeX3 Project Team, LaTeX font encodings, 2006. http://mirror.ctan.org/macros/latex/doc/encguide.pdf

[greek-usage]

  Apostolos Syropoulos, Writing Greek with the greek option of the babel package, 1997. http://www.tug.org/texlive/Contents/live/texmf-dist/doc/generic/babel/greek-usage.pdf

[cbfonts]

  Claudio Beccari, The CB Greek fonts, Εὔτυπον, τεῦχος № 21, 2008. http://www.eutypon.gr/eutypon/pdf/e2008-21/e21-a01.pdf

[teubner-doc]

  Claudio Beccari, `teubner.sty` An extension to the greek option of the babel package, 2011. http://mirror.ctan.org/macros/latex/contrib/teubner/teubner-doc.pdf

[babel-patch]

  Werner Lemberg, Unicode support for the Greek LGR encoding Εὔτυπον, τεῦχος № 20, 2008. http://www.eutypon.gr/eutypon/pdf/e2008-20/e20-a03.pdf