[HarfBuzz] Order of combining diacriticals

[Khaled Hosny]

On Fri, Jun 14, 2019 at 9:06 PM Eli Zaretskii <eliz at gnu.org> wrote:
>
> > From: Behdad Esfahbod <behdad at behdad.org>
> > Date: Fri, 14 Jun 2019 11:34:17 -0700
> > Cc: Khaled Hosny <dr.khaled.hosny at gmail.com>,
> >       "harfbuzz at lists.freedesktop.org" <harfbuzz at lists.freedesktop.org>
> >
> > On Thu, Jun 13, 2019 at 2:18 AM Eli Zaretskii <eliz at gnu.org> wrote:
> >
> >    . For fonts that have no 'hebr' features, Emacs performs
> >      substitution of known precomposed characters before it invokes the
> >      shaping engine.  In this case, it substituted U+FB31 for the
> >      sequence U+05D1,U+05BC, and passed the sequence U+FB31,U+05B0 to
> >      HarfBuzz.
> >
> > You should remove all such hacks.
>
> I understand that for HarfBuzz they are probably not needed, if the
> necessary functions for accessing the glyphs are provided (something
> that might not be true on Windows, where we don't use Freetype
> directly).

This functionality either depends on Unicode decompositions (or in
case of Hebrew hard-coded tables in HarfBuzz), so the font functions
used make no difference.

Regards,
Khaled