[XeTeX] fonts and diacritics

[Ulrike Fischer]

Am Sat, 13 Jun 2015 10:23:01 +0200 schrieb
hanneder at staff.uni-marburg.de:


> The problem is that I need diacritics for Indian languages. In  
> pdflatex I use ucs for the
> utf-input, which is not perfect, but works with a few tweaks.  Of  
> course there can be no serious
> problem in normal TeX, where you can in the worst case just type  
> things like \.n \d{t} and the
> like, which gives you the diacritics with any font (and mostly looks  
> quite good).
> 
> In XeTeX a considerable number of otf-fonts does not yield the  
> expected result. In the ADF fonts,
> for instance, regardless whether you use ṅ or \.n, it does not work.  
> Usually the macron \=a works,
> but not the underdot ṭ (\d{t}) or the dot above the ṅ (\.n).
> 
> 1. Did I miss anything (a trick in XeTeX)? Since other fonts (for  
> instance all TeXGyre fonts) work just fine, I thought not.
 
> 2. Or is it the case that some (actually many) fonts supposed to work  
> with XeTeX are weak in diacritics?

Yes, it can happen that the default definition of e.g. \d  leads to
a non existing glyh. xunicode maps \d{t} to 

  \DeclareUTFcomposite[\UTFencname]{x1E6D}{\d}{t}

but if your font doesn't have U+1E6D it doesn't work. 

You can then try

  \UndeclareUTFcomposite[\UTFencname]{x1E6D}{\d}{t}

then xelatex will fall back to the default "dot below accent":

\DeclareEncodedCompositeCharacter{\UTFencname}{\d}{0323}{0323}  %
Combining dot below

But if the font doesn't have U+0323 than it doesn't work either.
Then one could fall back to some older definition adn put a dot
below the t like pdflatex would do in OT1 encoding.

But it is better to choose your font so that it has the glyphs you
need. 


-- 
Ulrike Fischer 
http://www.troubleshooting-tex.de/