Re: Arabic Presentation Forms A vs. B
Sorry, stale mail alert. A./
Re: Arabic Presentation Forms A vs. B
At 10:19 PM 2/19/2004, [EMAIL PROTECTED] wrote: The Arabic data in question is for place names in a mapping product. So far, we have only received one complaint and it was a missed two element ligature from Arabic Presentation Forms B. Does this mean that the ligatures in Arabic Presentation Forms A do not apply to place names? Or did I just luck out? The Presentation forms are (with very few exceptions) simply ballast. There are some ligatures that do occur as single code point in some codesets, usually in places where the language is not Arabic, but ligatures of special Arabic words are needed (and used almost like symbols). In other words, nobody has attempted to verify the contents of these blocks and you are on your own. A./
Re: Arabic Presentation Forms-A
Philippe asked: > The "Arial Unicode MS" font does not have a glyph for the Rial currency sign > so I won't comment lots about it, even if it's a special ligature of its > component letters: > it's just regrettable that it's > not found in Arial Unicode MS (unless this Rial sign is traditional and no > more in actual use today). The Rial currency sign was recently added to the standard, so many fonts still don't have it. It was added for compatibility with an Iranian standard. > I'm not sure that the compatibility decomposition gives the accurate form > for rendering the traditional glyph coded for the currency symbol... It isn't supposed to. Compatibility decompositions are approximations, not necessarily the basis for building an Arabic ligation, especially for special cases like this currency sign. > FDFA;ARABIC LIGATURE SALLALLAHOU ALAYHE WASALLAM;0; > FDFA; 0635 0644 0649 0020 0627 0644 0644 0647 0020 0639 > 0644 064a 0647 0020 0648 0633 0644 0645; > FDFB;ARABIC LIGATURE JALLAJALALOUHOU;0; > FDFB; 062c 0644 0020 062c 0644 0627 0644 0647; > but the current presentation of > the alternate glyph chosen in Arial Unicode MS does not seems intuitive. That's an issue for Microsoft customers and testers of Microsoft fonts to determine. > Isn't there some requirement in Unicode to not change the common layout > which is part of the character identity and structural for the script? Such > interpretation problem does not occur in the presentation of U+FDFB (which > also has two rows in the representative glyph of Arabic Presentation Forms-A > charts). Is there an error here? Nope. Glyph shapes are not normative or prescriptive. As long as the identity of the character is clear, there might be an aesthetic faux pas, but not an error or a failure of conformance to the standard. > More generally, my question is related to the allowed modification of > layouts for ligature glyphs in fonts: are they allowed, Yes. > and how could they > be acceptably be represented when the plain-text character is not > compatibility-decomposed but rendered with a single glyph... By the code points in question, of course. For these word ligatures, which are really used as complete symbols, one would ordinarily not expect to enter the whole compatibility sequence of characters, anyway. Normal rendering engines don't produce these highly elaborated ligatures automatically from such sequences. > I was just wondering if their rendering in Arial Unicode MS is correct and > conforming to the required need to keep the interpretation, As long as the identity of the character is correct, which it seems to be, since you identified it, then one can say the font is "correct". > and in what measure the beautiful ligatures found in Unicode > charts are normative, In no measure. > as there's a very large difference with what Arial Unicde MS does There are large differences between Arabic fonts for *all* of the Arabic characters in the standard -- not just these word ligature symbols. --Ken
RE: Arabic Presentation Forms-A
> Philippe Verdy wrote: > > > #code;cc;nfd;nfkdFolded; # CHAR?; NFD?; NFKDFOLDED?; > > > # RIAL SIGN > > > fdfc;;; 0631 06cc 0627 0644; # ??; ?; ?; I should have disabled temporarily my email filter to send this one. All UTF-8 codes were replaced by ISO-8859-1 characters, substituing '?' instead of Arabic characters... I hope that the codepoints that I gave explicitly will still make my message readable... Well in your message you comment on the form shown in the charts, and I don't criticize them. I was just wondering if their rendering in Arial Unicode MS is correct and conforming to the required need to keep the interpretation, and in what measure the beautiful ligatures found in Unicode charts are normative, as there's a very large difference with what Arial Unicde MS does, with a distinct character layout, and no ligature, no kerning kashidas, and in some cases not even the contextual shaping of its embedded letters, so that the "Arial Unicode MS" font render these ligatures as their NFKD decomposition rendered in a single square. This may be valid if this was just a ligature, but in that case, why aren' those decomposition canonical like the ffi ligature ? __ << ella for Spam Control >> has removed Spam messages and set aside Newsletters for me You can use it too - and it's FREE! http://www.ellaforspam.com <>
RE: Arabic Presentation Forms-A
Philippe Verdy wrote: > > #code;cc;nfd;nfkdFolded; # CHAR?; NFD?; NFKDFOLDED?; > > # RIAL SIGN > > fdfc;;; 0631 06cc 0627 0644; # ??; ?; ?; > > > > The "Arial Unicode MS" font does not have a glyph for the > Rial currency sign so I won't comment lots about it, even if > it's a special ligature of its component letters: > > - where the medial form of U+06CC ARABIC LETTER FARSI YEH > (?) is shown on charts only as two dots (and not with its > "Arabic letter alef maksura" base form, as the comment in > Arabic chart suggests for Arabic letter yeh), which is I am not sure I understand what you are asking, but it is quite normal that the initial and medial form of letters Beh, Teh, Theh, Noon and Yeh loose their "tooth" and are thus recognizable only by their dots. Similarly, Seen and Sheen often loose their three "teeth". I find this particularly puzzling with the initial and medial forms of Seen, which becomes a simple straight line in most calligraphic styles. > > - located on below-left of the medial form of U+0627 (?) , U+627 is Alif, so it has no medial form. > > - and where the initial form of U+0631 (?) kerns below its > next two characters (sometimes with an aditional kashida > below its next three characters). This too is quite normal: the "tail" of Reh, Zain and Waw often kerns below the next letter. Compare it to Latin lowercase "j", which has a similar behavior. _ Marco
