[HarfBuzz] Itemising Japanese scripts

[Khaled Hosny]

On Sun, Apr 24, 2016 at 05:36:22PM +0200, Adam Twardoch (List) wrote:
> I think they should always be merged. They were emcoded as three
> scripts in Unicode in the early days when it was not at all obvious
> how the script property is to be used. Certainly the notion of script
> itemisation in OpenType came much later and the fact that OpenType
> unifies them under one "kana" tag clearly indicating the preferred
> usage in OT context. 

Right, I totally forgot about Hiragana and Katakana having the same
OpenType tag.

This leaves Han which has its own OpenType tag and that is what I have
been seeing most. So I wounder what other application do, should I try
something clever like see what scripts/features/lookups are in the font
and decide to merge the scripts if it is safe (i.e. merging or not should
have no effect on features applied), or should I just leave the current
behaviour and not worry about it?

Regards,
Khaled