Hi, Can you please tell me what the desired rendering of that sequence with malgun is? With Uniscribe I get three disjoint glyphs. Is *that* the desired rendering?
behdad On 13-03-20 11:03 PM, Dohyun Kim wrote: > Hi, > > When a sample input string, say "U+1100 U+1161 U+11F0", is processed > by current version of harfbuzz with some fonts, eg. malgun.ttf bundled > with windows 8, we get something like "U+AC00 U+11F0", which is not > good in its visual result. > > The reason is that there is discrepancy between Korean industrial > standad (KS X 1026-1: 2007) and Unicode normalization rule. > Malgun.ttf observes Korean standard only and does not care about > international unicode standard for normalizaiton. FYI, an English > translation of KS X 1026-1 is available at > ftp://std.dkuug.dk/ftp.anonymous/JTC1/SC2/WG2/docs/n3422.pdf. > > Normalization done by current harfbuzz is of course compliant with > unicode standard. "U+AC00 U+11F0", ie. precomposed character in > Hangul syllable block followed by trailing consonant Jamo letter, is > perfectly legal and is canonically identical to "U+1100 U+1161 > U+11F0". According to KS X 1026-1, however, this should not occur. > Section 5.3 of the Korean standard says: "A Wanseong syllable > block(U+AC00..U+D7A3) cannot be recomposed with Johab Hangul > letters(U+1100..U+11FF U+A960..U+A97C U+D7B0..U+D7FB) to represent > another Hangul syllable block." See also section 6.4 of this > standard. > > I have hesitated about posting this issue as harfbuzz is observing > unicode normalization rule. We cannot say it is a bug, and many other > libraries including glib and icu is doing the same as harfbuzz. I > believe that font developers should care about unicode standard as > well, which some fonts (jieupsida and hcr-lvt) are already supporting. > But as there are other fonts (malgun.ttf and unbatang.ttf) which do > not give us good result with current harfbuzz, I am now raising this > issue. Above all, malgun.ttf is now the default Hangul font for the > most widely used OS here in Korea. I have little knowledge about > programming languages, but the Korean standard mentioned above has > some sample code in its appendix. > > Best, > -- > Dohyun Kim > College of Law, Dongguk University > Seoul, Republic of Korea > _______________________________________________ > HarfBuzz mailing list > HarfBuzz@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/harfbuzz > -- behdad http://behdad.org/ _______________________________________________ HarfBuzz mailing list HarfBuzz@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/harfbuzz