The matter of ligatures arises fairly often in this discussion forum, often in relation to German Fraktur, but also in relation to English printing of the 18th Century and the use of fj in Norwegian.
In relation to regular Unicode the policy is that no more ligatures are to be encoded. My own view is that this should change. However, that is unlikely to do so. Earlier this year, following from a posting about Fraktur ligatures, I produced some encodings for ligatures using the Private Use Area. I have published them on the web at the following place. http://www.users.globalnet.co.uk/~ngo/golden.htm These are my own Private Use Area code point allocations for various ligatures. They are not in any way a standard yet they are a consistent set which may be useful to those who wish to use them. The only use I know of any of them in a published font is in the Code2000 font, produced by James Kass. James uses the code points of this set for ct, fj and ffj in his Code2000 font. I feel that it might well be of interest to you, for your background knowledge, to have a look at the encodings which I have produced, yet I mention that these Private Use Area encodings are a matter of some controversy. Using them could lead to documents existing which could not be text sorted alphabetically, or spellchecked. However, if someone is just wishing to produce a print out of some text with some ligatures in the text, then the golden ligatures collection can be useful. There seems to be a lot of theoretical possibilities for doing ligatures with Unicode fonts using advanced font technology using the latest computers, yet if, say, someone wants to set and print out a page of Fraktur, that possibility does not seem, as far as I know, to be a practically achievable result at the present time using a piece of text encoded in regular Unicode using a font which uses only regular Unicode encoding. Indeed, it seems more likely that one would need to use a Fraktur font with ligatures encoded with a code number below 255, that is, a font which is not Unicode compatible. The golden ligatures collection is Unicode compatible, though, as I say, it is not a standard. It is just one person's self-published writing. I like to think of it as an artform, much as if I had produced a painting and placed a copy of the painting on the web. That is, it exists, it may be interesting to people, yet it does not in any way prevent anyone else from doing something different and it does not require anyone else to take any notice of it, yet it is a cultural item in the world of art. So, it depends what one is wanting to do. If your enquiry is solely in relation to formal encoding of ligatures in regular Unicode, then the golden ligatures collection will be of no use to you. However, if you are producing a black letter font as part of your studies and would like to encode ligatures, then the golden ligatures collection might perhaps be of interest to you. For example, if such a font were encoded using advanced font technology, then the golden ligatures collection code points would not be the way to approach the problem, though they could, if you so chose, be used to provide an additional way of accessing the glyphs for people who were trying to produce printouts using, say, a Windows 95 or a Windows 98 system. If, however, such a font were produced as an ordinary TrueType font, then in order to access the ligature glyphs you would need code points in order to access the glyphs, one code point for each glyph. In order to be Unicode compatible, those code points would need to be in the Private Use Area range of U+E000 to U+F8FF. There is essentially complete freedom of choice as to which code points to use, though the lower part is perhaps best due to the suggestions about Private Use Area usage in the Unicode specification. However, the golden ligatures collection of code points is there for your consideration if you wish. Within my collection of code point allocations, ct is U+E707, fj is U+E70B, ch is U+E708, ck is U+E709, tz is U+E70F. These are all in the following document. http://www.users.globalnet.co.uk/~ngo/ligature.htm The ffj is encoded at U+E773 in the following document. http://www.users.globalnet.co.uk/~ngo/ligatur2.htm There are some black letter ligature encodings including pp at U+E76C and ppe at U+E77E in the following document. http://www.users.globalnet.co.uk/~ngo/ligatur5.htm The Private Use Area is described in Chapter 13, section 13.5 of the Unicode specification. There is a file named ch13.pdf available from one of the pages in the http://www.unicode.org website. The main index page of our family web site is as follows. http://www.users.globalnet.co.uk/~ngo William Overington 2 November 2002 -----Original Message----- From: Thomas Lotze <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] <[EMAIL PROTECTED]> Date: Friday, November 01, 2002 12:28 PM Subject: ct, fj and blackletter ligatures >Hi, > >the alphabetic presentation forms starting at UFB00 contain a number of >ligatures for latin scripts, among them the more common ones like fi and >fl, but also rather exotic ones like st. > >However, I find there are a couple of other ligatures in use, namely the >ct ligature (for instance to be found in Adobe Garamond), the fj >ligature, and a couple of ligatures common in blackletter typesetting: >among them ch, ck and tz. Would it be a good idea to propose these >ligatures for inclusion in Unicode? > >Cheers, Thomas > >-- >Thomas Lotze > >thomas.lotze at gmx.net http://www.thomas-lotze.de/ > >
