RE: Prepending vowel exception in Lontara/Buginese script ?

From: Peter Constable <>
Date: Mon, 25 Jul 2011 20:30:15 +0000

From: [] On Behalf Of Philippe Verdy

>>> What would be the behavior of a font that would use GSUB entries (or
>>> ligatures) in a feature to implement the reordering that NO renderer
>>> currently implements for Buginese ? What will happen later if the
>>> renderer does implement it ?
>> Your question is no coherent: OpenType features cannot be used to trigger re-ordering.
> Hmmm... Your reply is also incoherent:
> (1) There are lots of OpenType features registered that actually perform
> contextual reordering in Indic scripts

No, there are not. There is no way in OpenType Layout table to describe reordering. There are features to select alternate glyphs in cases where re-ordering may also be involved, but no features that trigger a reordering.

> (3) Some of them are for pre-base reordering

No, they do no trigger re-ordering; they allow for selection of alternate glyphs.

> It's strange : many new international fonts have been added after the release
> of Windows 7. And the CPL explorer extension still detects that the fonts support
> some scripts.

You'll have to clarify (give me specific repro details) for me to comment.

> OK, is it possible to have the Saweri and Code2000 fonts recognized

Unfortunately no. But that really has no impact on any functionality in applications, so I don't see that as a big concern.

> This brought me to the question of testing other South-East Asian
> Brahmic scripts, like Hanunoo, Buhid, Javanese, or Balinese. It seem
> that they have the same rendering problem in a few cases for prepended
> vowels (plus other problems remaining in Khmer and Burmese for some
> contextual forms).

Those insular SE Asian scripts are also not supported in Win7, so the re-ordering issues are exactly the same as for Buginese. Burmese also was not supported in Win7. Khmer has been supported since Vista, though; if you have issues for Khmer, please clarify the details.

> The rendering problem will be recurring with all other pending Brahmic scripts
> (still not encoded) that feature prepended diacritics. Why can't we have now a
> registered OpenType feature for handling those mandatory contextual
> reorderings (at least for the most frequent cases), waiting for a full support of
> the script in text renderers?

I will repeat yet again -- please take note: OpenType Layout does not provide any means for describing re-orderings in a font. No such feature is feasible.

Received on Mon Jul 25 2011 - 15:44:00 CDT

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