Den 2011-09-11 18:53, skrev "Peter Constable" <peter...@microsoft.com>:
> There's no requirement that the width of glyphs in a monospaced font be 1 em. > I would agree, though, that if a monospaced font forms a ligature of a pair > like <0066, 0069>, then it should be twice the width (not necessarily 2em) of > single-character glyphs. That's fine (assuming the ligature is well designed, in the case of a monospace font connecting the bar of the f to the top serif of the i and only that). > In a monospace font, nothing prevents the glyph for FB01 being a ligature, and > some monospaced fonts do have a ligature glyph for that character. Fine too. But see below. > Of course, in a monospaced font, the glyph for that character should be the > same width as all other glyphs. So if it's not a ligature, then the "f" and > "i" elements still need to be narrower than the glyphs for 0066 and 0069. > > Hence, in a monospaced font, FB01 certainly should look different from <0066, > 0069>, regardless of whether ligature glyphs are used in either case. If "monospace" is interpreted that rigidly, then it is much better *not* to have any glyph at all for FB01 (and other characters like it) in a "monospace" font. /Kent K > > Peter > > -----Original Message----- > From: unicode-bou...@unicode.org [mailto:unicode-bou...@unicode.org] On Behalf > Of Philippe Verdy > Sent: Saturday, September 10, 2011 10:33 PM > To: Michael Everson > Cc: unicode Unicode Discussion > Subject: Re: ligature usage - WAS: How do we find out what assigned code > points aren't normally used in text? > > 2011/9/11 Michael Everson <ever...@evertype.com>: >> On 11 Sep 2011, at 00:23, Richard Wordingham wrote: >> >>> A font need not support such ligation, but a glyph for U+FB01 must >>> ligate the letters - otherwise it's not U+FB01! >> >> Not in monowidth, it doesn't. > > I also agree, a monospaced font can perfectly show the dot and ligate the > letters, using a "double-width" (2em) ligature without any problem, or simply > not map it at all, or choose to just map a composite glyph made of the > 1em-width glyphs assigned to the two letters f and (dotted) i without showing > any visible ligation between those glyphs (this being consistant with > monospaced fonts that remove all ligations, variable advances and kernings > between letters). > > You could as well have a font design in which all pairs or Latin letters are > joined, including in a monospaced font, in which case you should not see any > difference between FB01 and the pair or Basic Latin letters. Joining letters > is fully independant of the fact that the upper part of letter f may or may > not interact graphically with the presence of a dot. If the style of letter > glyphs does not cause any interaction, there's no reason to remove the dot > over i or j in the "ligature" or joining letters. > > You should not be limited by the common style used in modern Times-like fonts > (notably in italic styles, where the letter f is overhanging over the nearby > letters). Other font styles also exist that do not require adjustment to > remove the dot, or merge it with a graphic feature of the preceding letter f > which is specific to some fonts. > > As the pair of letters f and (dotted) i is perfectly valid in Turkish, there's > absolutely no reason why the fi ligature would be invalid in Turkish. But > given that this character is just provided for compatibility with legacy > encodings, I would still not recommand it for Turkish or for any other > language, including English. This FB01 character is not necessary to any > orthography and if possible, should be replaced by the pair of Basic Latin > letters (and in fact I don't see any reason why a font would not choose to do > this everywhere) > > -- Philippe. > > > >