Re: New version of UTF-8 on Linux

[Christopher Fynn <cfynn@xxxxxxx>]

Arne Götje (高盛華) wrote:

> 3. Varient selectors: OTF includes a feature in the GSUB table to 
> specify which glyphs should be used for which codepoint in a specific 
> region (simplified chinese, trad. chinese, japanese, etc.). Currently 
> OO.o is the only application supposed to support this feature.
> I will have to study the Unicode spec how the varient selectors in 
> Unicode are supposed to work. However, I don't know any application to 
> support this feature, and if we would want to use it, we would have to 
> 'define' a standard, *which* of the varient selectors represents which 
> presentation form.

The OpenType spec allows you to define language specific lookups. Generally 
all lookups are placed under the 'dflt' (default) language tag for each 
script - however you can add additional language tags and place lookups 
under these and so display different glyph variants based on language. In 
the case of CJK you could e.g. display different forms for a character 
dependent on whether the text is tagged or formatted as Traditional Chinese, 
Simplified Chinese or Japanese. This does not require the use of variant 
selector tags  - though the language of the text needs to be specified using 
some high level markup.

Variations using Unicode variant selectors have to be defined in the Unicode 
Standard itself.

- Chris


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Linux-UTF8:   i18n of Linux on all levels
Archive:      http://mail.nl.linux.org/linux-utf8/