Hi Philippe, thanks for your reply. I was confused by http://www.unicode.org/faq/unsup_char.html , which states > All default-ignorable characters should be rendered as completely invisible > (and non advancing, i.e. "zero width"), if not explicitly supported in > rendering. Do I understand correctly that, if the choseong filler is used when there's no leading consonnent before a medial vowel, it should be rendered as visible; otherwise become non-advancing (similarly, if the jungseong filler is used to replace a missing medial or final vowel, it should be rendered as visible; otherwise become non-advancing) ? i.e. <U+115F>, or <U+1161, U+1160>, or <U+115F, U+112B> -- should the fillers be rendered as non-advancing?
regards, Konstantin 2013/3/18 Philippe Verdy <[email protected]>: > The "Default ignorable" property has nothing to do with rendering or > being zero-width, it's just a matter of collation (comparing strings > for similarity, for plain-text searches, or sorting them), it does not > necesarily mean that the character is zero-width (that's a rendering > property). > > Characters that are "default ignorable" may still have an effect on > cluster boundaries used when editing texts, if you count manually the > number of zero-width characters (by pressng the left or right arrow > fnction keys.) As long as the rendering is correct, editors may allow > you to place insertion points between them. > > U+115F is the choseong filler (used when there's no leading consonnent > to place before a medial vowel), U+1160 is the jungseong filler (used > to replace a missing medial or final vowel). > > You're right when saying that there should be two clusters in > <U+115F, U+1161>, <U+112B, U+1160> > - The first one is a isolated vowel A, it should become spacing but > U+115F is just used as an invisible holder for the vowel, > - The second one is an isolated consonnant KAPYEOUNPIEUP, and the > U+1160 filler will remain invisible except that it iis used here so > that it explicitly terminates the cluster if it was followed by a > leading consonnant or dirctly by a "defective" vovel. > > But the U+115F and U+1160 Hangul fillfers remain default ignorable in > collation. And there's no bug about this. > > 2013/3/18 Konstantin Ritt <[email protected]>: >> 2013/3/18 Konstantin Ritt <[email protected]>: >>> The user reports Korean text rendering issue with any modern Hangul >>> font when U+115F and U+1160 are handled like default_ignorable code >>> points. >>> [quote]With input string "U+115F U+1161 U+112B U+1160", we get three >>> zero-width glyphs instead of two; this is wrong.[/quote] >>> I did check some Hangul font and found that either U+115F or U+1160 >>> zero-advances, not both. When handling them like default ignorable, >>> the rendered text seems to lack some advancing. >>> Since I know nothing about Korean typography, I'd like to ask here: >>> what is the reason for U+115F and U+1160 to be default ignorables and >>> shouldn't that be revised?
