[HarfBuzz] Question on converting UTF-8 codepoints to complex glyphs

[Richard Wordingham]

On Thu, 11 Apr 2019 18:03:10 +0000
Paul Daughetee <Daughetee at finaldraft.com> wrote:

>  டு  [...] 
> is the ligature formed by the codepoints corresponding to the glyphs
> ட and உ.

No!  You already have been told by Jonathan Kew.

டு is the codepoint sequence <U+0B9F TAMIL LETTER TTA, U+0BC1 TAMIL
VOWEL SIGN U>; it is **not** the ligature of ட <U+0B9F TAMIL LETTER
TTA> and உ <u+0B89 TAMIL LETTER U> .  If you don't believe me, paste
them into Word and use alt/X to convert the characters to their
codepoints.

Richard.