[HarfBuzz] unsafe to break

[Khaled Hosny]

On Sat, Nov 11, 2017 at 08:39:09AM +0700, Martin Hosken wrote:
> Dear Behdad,
> 
> Please could you explain the purpose and function of
> HB_GLYPH_FLAG_UNSAFE_TO_BREAK. Is this about line breaking? grapheme
> clustering?

It is about shaping after line breaking. IIUC, unsafe to break means you must
reshape if you break here (up to the next/previous safe to break point),
but actual break points have to be identified by the client as usual.

IMHO, that is an optimization for the clients that want to do the right
thing after breaking but don’t want to re-shape text needlessly.

Regards,
Khaled