Arabic transliteration macros

[Idris Samawi Hamid <ishamid@lamar.colostate.edu>]

Dear syndicate,

I have been using some ugly/naive macros for scientific transliteration of 
Arabic up to now. I recently overhauled these after studying the enco-def.tex 
method. These might be useful for others who have to transliterate Arabic. (I 
have written my own scientific transliteration by the way, based on the German 
ZDMG system:)

http://www.gsp-online.org/journals/journaldocs/shi/transliteration.pdf

imacron occurs very frequently in Arabic transliteration, in virtually every 
system. In Latin Modern the macron on the `i' is too large and looks really 
bad when used frequently. I've redefined it, and would suggest that, for lmr 
anyway, that something like the imacron definition below works much better 
than the default.

On the other hand, I need to make the imacron definition more general to 
include the bold case (which needs a thicker macron). How can I add a 
conditional to the macro definition of \itextmacron so that it selects its 
argument based on whether \tf (and the like) or \bf (and the like) is in 
effect?

I wish that TeX had a simple \iffont test but maybe there is an easy way to do 
that?

If there are any other suggestions or comments to improve or streamline this, 
please let me know.

Best
Idris

===================arabic-trans.tex===================
\setupoutput[pdftex]

%%%=====================low-level====================
\def\SHIFT#1{\dimen0=.00#1ex \multiply\dimen0 by\fontdimen1\font
    \kern-.0156\dimen0} 
% compensate for slant/italic in lower accents

\def\USHIFT#1{\dimen0=.00#1ex \multiply\dimen0 by\fontdimen1\font
              \kern.0156\dimen0} 
% compensate for slant/italic in upper accents

\def\buildtextbottombreve{\bottomaccent{.25ex}{0}{19}{\textbreve}}

%%%=====================basic transliteration====================

\def\Al{\~a\~l}
\unexpanded\def\h#1{{\buildtextbottombreve #1}}
\unexpanded\def\.#1{{\buildtextbottomdot #1}}
\unexpanded\def\:#1{{\buildtextaccent\textdotaccent #1}}

%%%=====================ayn-hamzah====================
\def\cupd{\leavevmode%
          \USHIFT{14}\rotate[rotation=180,location=high]{\txx c}%
          \SHIFT{14}}

\definecharacter AYN    {\leavevmode\raise.9ex\hbox{\txx \USHIFT{1} 
c\SHIFT{0}}{}}
\definecharacter HAMZAH {\leavevmode\kern.07em\raise.9ex\hbox{\cupd}{}}

\def\'{\HAMZAH}
\def\`{\AYN}

%% replace grave and acute
\unexpanded\def\Grave#1{{\accent"12 #1}}
\unexpanded\def\Acute#1{{\accent"13 #1}}

%%%=====================imacron====================

\unexpanded\def\itextmacron{\leavevmode\rlap{\USHIFT{14}\kern.033em\raise1.375
ex%
                            \hbox to .21243em{\leaders\hrule height 
.067ex\hfill}}}

\definecharacter imacron   {\buildtextaccent\itextmacron \dotlessi}

\starttext

Long vowels:

\blank[small]

\=Adam \ kit\=ab \ {\it \=Adam \ kit\=ab }

\=Im\=an \ M\=irz\=a \ {\it \=Im\=an \ M\=irz\=a}

\=Ul\=a \ n\=un \ {\it \=Ul\=a \ n\=un}

\blank

Consonants:

\blank[small]

\b T\=ar \ \b ma\b tal \ {\it \b T\=ar \ \b ma\b tal}

\.Husayn \ ma\.hall \ {\it \.Husayn \ ma\.hall}

\h H\=alid \ ma\h hzan \ {\it \h H\=alid \ ma\h hzan}

\b Dh\=at \ h\=a\b d\=a \ {\it \b Dh\=at \ h\=a\b d\=a}

\.S\=ali\.h \ ma\.sdar \ {\it \.S\=ali\.h \ ma\.sdar}

\.D\=amin \ mu\.dill \ {\it \.D\=amin \ mu\.dill}

\.T\=ariq \ ma\.tar \ {\it \.T\=ariq \ ma\.tar}

\.Z\=ahir \ ma\.zhar \ {\it \.Z\=ahir \ ma\.zhar}

\:G\=afir \ \:gufr\=an \ {\it \:G\=afir \ \:gufr\=an}

\blank

Glottal stops:

\blank[small]

\`Al\=i \ ba\`du \ {\it \`Al\=i \ ba\`du}

\'Alif \ Qur\'\=an \ {\it \'Alif \ Qur\'\=an}

\blank

Assimilation:

\blank[medium]

a. definite article

\blank[small]

Ibnu \~al-F\=aris {\it Ibnu \~al-F\=aris}

Kit\=abu \Al-S\=ibawayh {\it Kit\=abu \Al-S\=ibawayh}

\blank[medium]

b. t\=a\' marb\=u\.ta\~h

\blank[small]

\h hal\=ifa\~h {\it \h hal\=ifa\~h}

\h hal\=ifa\~tu \Al-nabiyy {\it \h hal\=ifa\~tu \Al-nabiyy}

\stoptext
======================================================

============================
Professor Idris Samawi Hamid
Department of Philosophy
Colorado State University
Fort Collins, CO 80523