Re: Language Tagging And Unicode

From: Peter Constable (
Date: Wed Jan 19 2000 - 12:54:38 EST

>Does this mean that Windows' OpenType layout services does
       support language system (even if MS are not currently making
       use of this in Office etc. applications)?


>The OpenType spec says e.g. for GSUB (glyph substitution)

>1 Locate the current script in the GSUB ScriptList table.
>2 If the language system is known, search the script for the
          correct LangSys table; otherwise, use the script's default
          language system (DefaultLangSys table).
>3 The LangSys table provides index numbers into the GSUB
          FeatureList table to access a required feature and a number
          of additional features.

>Do MS applications that use OT currently bypass (2) and just
       go straight to the default language system for any given

       My understanding is that Uniscribe *currently* does this (but I
       expect that will change).

>(Text in word Word at least has a language attribute so
       presumably that application "knows" the language system.)

       Currently, Word only uses this for selecting proofing tools.

>I've been trying to build OT fonts based on the assumption
       that applications will use the LangSys table. Am I wasting my

       No, I pray not! I doubt you're alone on this.


This archive was generated by hypermail 2.1.2 : Tue Jul 10 2001 - 17:20:58 EDT