Choosing the Set of Renderable Strings

[James Kass via Unicode]

In response to Richard Wordingham,

Sorry I can't answer many of your questions.  Hoping someone who can
does.  Note that although the proposal gave canonical combining class
zero to both the tone marks and the vowel signs, the on-line Unicode
data gives canonical combining class 230 to the tone marks.

> **The placement may be different to that of MAI KANG
> in /bɔː waː/ ᨷᩴ᩠᩵ᩅᩣ <BA, MAI KANG, TONE-1, SAKOT, WA,
> SIGN AA> or ᨷᩴ᩠ᩅ᩵ᩣ <BA, MAI KANG, SAKOT, WA, TONE-1,
> SIGN AA> - I don't know whether the first or the second
> tone mark is dropped.

FWIW, neither is dropped in the display here, although they don't
display identically.  The first string shows TONE-1 positioned to the
right of MAI KANG, the second string superimposes them.  (Windows 7
running LibreOffice in order to enable the USE from HarfBuzz.)

> (Getting the tone and MAI KANG to interact after <NA, tone,
> SIGN AA, MAI KANG> has formed the NAA ligature from
> <NA, SIGN AA> seems impossible.

Substituting U+1A36 TAI THAM LETTER NA for BA in the above strings,
ᨶᩴ᩠᩵ᩅᩣ  ᨶᩴ᩠ᩅ᩵ᩣ, and trying to get the ligature are in the attached
*.PNG file. Here's the four strings for the PNG:

\u1A36\u1A74\u1A75\u1A60\u1A45\u1A63
\u1A36\u1A74\u1A60\u1A45\u1A75\u1A63
\u1A36\u1A75\u1A63\u1A74
\u1A36\u1A63\u1A74\u1A75
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