[XeTeX] color some Hebrew vowels

[Jonathan Kew]

On 19 Sep 2009, at 07:53, Lorenz Haas wrote:

> Hi Tilman,
>
> I've tried your suggestion in all possible variations, but the dont  
> have any
> effects. Unfortunately.
>
> As soon i use any kind of a command (e.g \textit{#1}) inside my "hem"
> definition the vowels get shifted.

Yes; this is a limitation of how xetex interacts with opentype fonts.  
When you insert \special{}s to change the color, or anything else that  
breaks up the "run" of consecutive characters being typeset from the  
same font, opentype features such as diacritic positioning will not  
apply across that boundary. The same thing would apply if you tried to  
color the "i" of an "fi" ligature: the presence of the color-changing  
command would prevent the ligature forming.

One solution would be to use luatex, which should allow you to color  
the vowels independently and still apply the proper positioning rules;  
however, you might have to do some fairly technical setup in order to  
get there.

A possible workaround in xetex would be to typeset the complete word  
(including vowels) in red, and then overlay this with a vowel-less  
copy typeset in black. (Use boxes, \llap, or whatever to overprint the  
second version.) Writing a handy macro to encapsulate this is left as  
an exercise....

JK


> That the coloring works fine (only for the
> enclosed vowels/letters) I currently use:
>
> \usepackage{bidi}
> \newfontface\HebFont[Mapping=tex-text,Script=Hebrew]{SBL Hebrew}
> %\newfontface\HebFont[Mapping=tex-text,Script=Hebrew]{Ezra SIL} %  
> both fonts
> dont work
> \definecolor{hebcol}{rgb}{1,.1,.1}
> \newcommand{\he}[1]{{\RL\HebFont #1}}
> \newcommand{\hem}[1]{\LR{\textcolor{hebcol}{#1}}}
>
> \he{ל\hem{וֹ}מ\hem{ֵ}ד} % this is "lomed" with וֹ and ֵ  
> colored.
>
>
>
> Thanks,
> Lorenz
>