Ancient Egyptian Hieroglyphs give possibly the clearest exposition of what is involved here. Glyph direction (almost) always followed the text direction. RTL was the standard, but LTR sometimes where the purpose suited. TTB commonplace. A monumental inscription may use all permutations. This basic behaviour is compatible with the Unicode treatment of 'Old Italic'. Modern expositions of texts usually write LTR for pragmatic or pedagogical reasons. Mirroring of individual signs was used, for example, to produce a more visually pleasing symmetry in the writing of the names of certain kings and deities. Occasionally glyphs were rotated from their conventional pose.
Incidentally Hieroglyphs have been talked about in conjunction with Unicode since the beginning but difficulties, such as the character repertoire appropriate to a form in use for over 3000 years, seem to have held back making any progress. A situation that some of us hope will change over the next year or two. The wrong time to delve into a detailed discussion of this subject and issues related to plain text representation. It is certainly the case that a full treatment of the Hieroglyphic script involves considerations such as XML mark-up that are outside of the Unicode domain. Nevertheless there is a case (however strong or weak) for Unicode admitting mirroring and simple rotation transformations. The phenomenon not only occurs in some ancient scripts but also in modern Latin usage, most notably in advertising. The fact that Old Latin already requests a glyph transformation according to bidi context supports the view this is not entirely inconsistent with Unicode philosophy. Because such mechanisms are more general than a specific script such as Archaic Greek, a specific Unicode proposal may want to raise the points but no need for an ARCHAIC_GREEK_MIRROR qualifier. IMO this functionality would be better introduced as a generic feature if appropriate and UTC are amenable, not on a script by script basis. Bob Richmond Saqqara Technology From: "Dean Snyder" May 25, 2004 8:19 PM > > Archaic Greek exhibits variable glyph stance, that is, glyphs can be > flipped horizontally or even vertically, usually dependent upon the > direction of the writing stream. > > How should variable glyph stance for the same characters in the same > script be dealt with in Unicode and in a Unicode proposal? >
