On Sat, 2 Jun 2018 11:06:43 +0200 Otto Stolz via Unicode <unicode@unicode.org> wrote:
> Am 2018-06-02 um 06:44 schrieb Richard Wordingham via Unicode: > > In Latin text, one can indicate permissible line break opportunities > > between grapheme clusters by inserting U+00AD SOFT HYPHEN. What > > low-end schemes, if any, exist for such mark-up within grapheme > > clusters? > > What about U+200B ZWSP? > > this character is intended for invisible word > > separation and for line break control; it has no > > width, but its presence between two characters > > does not prevent increased letter spacing in > > justification Thanks for the suggestion, but it's not likely to work: Within a word and with a proper layout implementation, using ZWSP would be worse than using backing store <character-1, SHY, character-2>. 1) In the sequence <letter-0, character-1, ZWSP, character-2, letter-1> realisation of the break should definitely result in <letter-0, character-1> on one line and in <character-2, letter-1> on the next line, whereas in visual order, character-2 should precede character-1. 2) Use of ZWSP will usually result in a dotted circle even when the break does not occur. 3) ZWSP will result in a mandatory word boundary. That will cause problems with the spell checker. I've experimented (http://wrdingham.co.uk/lanna/renderer_test.htm#test_and_tell) with the combination <letter, right matra> where there is a default grapheme cluster boundary between the two characters. I get generally better results with SHY than ZWSP. The downside was that the rendering systems I tried seemed to insist on inserting the glyph of U+002D or U+2010, rather than the glyph of U+00AD. Incidentally, does CLDR define the rendering of soft hyphen, or is one entirely at the mercy of the application? Richard.
