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 [email protected] http://lists.freedesktop.org/mailman/listinfo/harfbuzz
