I am writing a document with XeLaTeX in which I use IPA characters in italicized text. After trying a few fonts with extensive IPA support like Gentium Plus, Brill or Charis SIL, I encounter the same problem: the vowels
ɑ are given the same character in italics, even though they are differentiated in plain text.
While not a tragedy, this is both quite shocking and a little troubling. I assume that a number of people will also have come across this issue.
Is there a straightforward way in TeX to get actually different italic shapes for the two characters?
-- Edit for clarification:
One would think that losing the distinction between two characters is grave enough in and of itself. Still, it does have actual implications: you become completely unable to capture the distinction between words like 'Sam'
/sam/ and 'psalm'
/sɑm/ (in some English varieties).
Let's see it in action in a French gloss to realize that this can indeed be a big issue:
Le chien a mis sa patte dans ma pâte. /lə ʃjɛ̃ a mi sa pat dã ma pɑt/ the dog has put its paw in my dough "The dog put its paw in my dough."
In italicized text (for many reasons: an italicized line in glosses, a transcribed word quoted in italics, etc.), because of the problem reported in this post the
/pɑt/ distinction is completely lost.