[XeTeX] Incorrect rendering of Vedic Sanskrit accents

[maxwell]

On 2015-05-22 14:24, Bobby de Vos wrote:
> Some minority languages (that is, not the dominate language using a
> particular script) often use combining marks in ways not envisioned in
> order to extend the script to cover all the sounds in the minority
> language. So for those minority languages, having a dotted circle show
> up is not very helpful.

Yes, but most font providers don't have such minority languages in mind. 
  (SIL would be an exception.)

That said, I've worked with such minority languages (including ones that 
are just in the process of defining their writing systems), and I don't 
recall a case where it was necessary to use a combining character 
without a base character.  Also, the original version of xetex was 
developed by SIL (SIL also has some useful fonts), and SIL works with 
such minority languages exclusively.  So while it may be possible for 
the *tex engine or fonts to omit the dotted circle, it doesn't seem to 
be a very high priority.

That's of course not the same as saying it's never necessary, and the 
OP's need to show it in tables is one valid (IMO) use case.  If it can 
be done with the method I mentioned, then that's probably good enough, 
at least for that use case.

    Mike Maxwell