In other words, that circumflex is an epigraphic notation. This means three distinct levels of analysis of the text: one for Chi, one for the small letter above it noting something about the Chi, and another for the circumflex noting something about the Chi itself.
This causes a major problem : how to separate cleanly those levels of representation when diacritics are NOT supposed to modify a letter orthographically ? 1) use an upper layer protocol (this is the position constantly adopted, but it has its limits). 2) use a special invisible combining character used as prefixes (with combining class 0 to avoid reorderings and other ambiguous combined forms caused ny normalizations) to separate and provide an unspecified additional semantic to the standard diacritics encoded after them. 3) Or possibly several of such special invisible combining characters in a coherent set (we could have 16 of them, encoded at once in one column in the special plane, each one with a numeric property which does not designate how it will be used in actual texts, in a way similar to the multiple variant selectors or multiple PUAs that are not very well fitted for combining characters), it if is needed to make semantic distinctions between these multiple (but optional) epigraphic levels. Le 11 mars 2012 14:06, Michael Everson <[email protected]> a écrit : > On 11 Mar 2012, at 12:05, Denis Jacquerye wrote: > >> Stacked letters are also found in some Greek manuscripts. >> See the page >> http://www.archive.org/stream/revuearchologi27pariuoft#page/156/mode/1up >> with some examples: Nu, omicron, omicron and Greek circumflex (tilde), >> chi and Greek circumflex. >> Would these also have to be represented by combining characters? > > Yes, but in this case I don't think that circumflex is part of the > superscript letter per se. It's a base letter with a combining letter, and > the whole thing has a mark over it to show it's an abbreviation. (There is > obviously no chi-circumflex in Greek orthography.) > > Michael Everson * http://www.evertype.com/ > > >
