[Harfbuzz-indic] Unicode vs OpenType: nukta after vowel

[Shriramana Sharma]

On 06/29/2011 02:29 AM, Jonathan Kew wrote:
> Users think of this as being "the same nukta sign" as they use to
> modify consonants; they're just using the script's well-known
> "modifier" symbol in new ways to express additional modifications.

Users think it is "the same nukta" because as was pointed out, "nukta" 
in common language just means "dot". However, in Unicode, the term 
"nukta" has a specific meaning, a consonant modifier, with the 
implication of CCC=7.

Therefore, IMHO the appropriate behaviour is to use the encoded Nukta 
characters 093C etc only immediately after consonant characters and for 
all other cases to use MODIFIER LETTER characters or COMBINING 
characters. Note that Devanagari also uses MODIFIER LETTER APOSTROPHE 
for Dogri etc -- and those are placed after the vowel sign (if any). 
Similarly, if there is a diacritic that doesn't modify the consonant but 
the vowel/syllable, it would only be appropriate to place it after the 
vowel sign if present.

-- 
Shriramana Sharma