Are you telling to crate different style for Latin usage Unicode Inc just copied some letters/symbols from Greek script assigned new code-point to each copied letter/symbol and assigned "Latin" name?
Tulasi From: Philippe Verdy <[email protected]> Date: Sun, Aug 14, 2011 at 2:57 PM Subject: Re: Greek Characters Duplicated as Latin (was: Sanskrit nasalized L) To: Richard Wordingham <[email protected]> Cc: unicode Unicode Discussion <[email protected]> 2011/8/14 Richard Wordingham <[email protected]>: > On Sat, 6 Aug 2011 17:25:11 -0700 > tulasi <[email protected]> wrote: > >> - Why did Unicode Inc copies some letters/symbols from Greek-script >> irresponsibly and renamed as Latin-script? >> - Why din't it (Unicode Inc) use same Greek letters/symbols? > > U+00B5 MICRO SIGN is an ISO-8859-1 character, and was therefore > included as U+00B5. It normally precedes a Latin-script letter, and > therefore it actually makes sense to treat it as a Latin-script > character, and possibly give it a different shape in these contexts to > the shape of the Greek letter in Greek text. > [...] > U+0216 OHM SIGN is similar to U+00B5 MICRO SIGN, except that it is used > on its own. Whether it should be merged with U+03A9 GREEK CAPITAL > LETTER OMEGA is debatable, but that is what has been done. My opinion is that you could retain the same argument for the OHM SIGN and the MICRO SIGN, because they are *both* used along with Latin letters to create SI unit abbreviations: the units in kiloohms and megaohms are not exceptional and most often abbreviated, and in fact much more frequently used than units in ohms alone (especially in electronic). So it's natural that Latin fonts will want to line up the style of the ohm unit symbol with the style of by Latin letters ('k' and 'M') used for noting the standard multiples, and adopt a typographic style that will be more coherent with Latin typography than Greek typography (for example, sans-serif styles are much less preferable to serif styles in Greek than in Latin, and variable weights of strokes and rounded strokes are much more frequent and prefered in Greek typography; additionally Greek typography is often nearer from the handwritten cursive style, and so exposes a small slant on glyphs, even in non-italic styles, just like what happens in the cursive style of Latin). If users want fine typography that will work best for Latin and Greek, including in technical publications, they will want also a contrast between the ohm sign and the Greek capital omega letter (there's also a perception of the separation of scripts between technical SI units, perceived all as Latin, and native Greek texts, even in monolingual texts in Greek). So I don't see the "dual" encoding of the Ohm sign and the Greek capital Omega as a problem, even if there are compatibility mappings between them. And I'm not even speaking here about the usage in mathematic formulas, or in IPA which is not relevant here, but has similar consideration about their perceived separation of scripts for distinct usages (they actually don't speak the same language: technical notations are more international and language-neutral, whereas there remains a strong tradition for typesetting humane languages differently). This also reminds me of the differences that occur between languages about how to best typeset many Latin letters or diacritics according to the language (see the case of German capital letters, which should avoid the heavy contrast of variable stroke weights, because these capitals are much more frequent in German; see also the case of the acute accent or the hacek which should look very differently in Czech). But these cases can be handled by language-specific glyph substitutions in OpenType fonts. This is not the case of technical symbols like the ohm sign and the micro sign, for which there is no relevant language code selectable in source documents: for this, all we can do is to use separate code points (But you could argue that an OpenType feature could also allow selecting the technical symbols in technical documents, if there's support in word processors for selecting such typographic feature; this is probably overkill because technical documents will anyway select separate fonts and styles for technical notations; in which case the separation of codepoints is unnecessary, except in plain-text documents if one wants to preserve the semantic distinction, translated in glyphic distinctions when the document is rendered). Anyway, all fonts that only provide a glyph for a single version of these letters should probably also map the other one, even if they don't display the expected distinction (and may be this is not needed for the specific font design), but text renderers will also be able to provide fallbacks from one style to the other if one codepoint in the pair is not mapped (possibly by using another fallback font). But given that most Greek fonts also contain Latin letters, they should really map both characters (the Greek letter, designed specifically for the Greek alphabetic usage in humane Greek texts, and the technical symbol, possibly with a separate style matching with the Latin letters also mapped the same font). -- Philippe.
