[XeTeX] Polytonic greek and XeLaTeX

[Jonathan Kew]

On 2 Jan 2008, at 4:46 pm, John Was wrote:

> Hi
>
>> U+1FBF GREEK PSILI is a different matter; this is a "spacing" version
>> of the mark, and should not normally be used in text, as far as I
>> know. I suppose it could be useful when writing about the diacritic
>> itself, rather than using it in combination with a vowel.
>>
>> JK
>>
>
> The Greek asper and lenis (as classicists normally refer to them) are
> actually very useful in roman-alphabet contexts for transliteration of
> Arabic (etc.) names.

Hmm... yes, I suppose that's a possibility. But I think the  
characters that are expected to be used for Arabic transliteration  
are U+02BE MODIFIER LETTER RIGHT HALF RING and U+02BE MODIFIER LETTER  
LEFT HALF RING, rather than the "comma" forms. (See their annotations  
in the Unicode standard.)

And if you do specifically need a more "comma-like" character, the  
appropriate choices would be U+02BC MODIFIER LETTER APOSTROPHE and U 
+02BD MODIFIER LETTER REVERSED COMMA. So I still don't think U+1FBF  
is the right choice!

> I mentioned in a different thread that this is one
> case where it would be useful to have the ability to add my own  
> kerns to a
> font, just in case the asper and lenis did not look well adjacent  
> to a roman
> capital letter.  (There's no particular reason why a font designer  
> working
> out the best kerns for the Greek area of Unicode should think to  
> supply
> kerns between Greek characters and roman-alphabet characters, but it's
> typical of academic work that this kind of odd and unpredicted  
> requirement
> may arise.)

The case for asking font designers to include appropriate kerns in  
the font becomes a bit stronger, at least, if you use the appropriate  
characters from the U+02xx block, as these can reasonably be expected  
to be used in conjunction with Latin letters. But I can certainly  
understand that you may have "odd" requirements, especially in  
academic/technical contexts, and want additional kerns to improve the  
result.

JK