Re: More than Combining characters

[Theppitak Karoonboonyanan <thep linux thai net>]

Hello,

May I add something?

On Wed, Sep 10, 2003 at 11:21:26AM +0900, Jungshik Shin wrote:
> 
>   That is one way. See how Thai shaper is written in Pango. Currently it
> doesn't use opentype features. Instead, it maps a sequence of Unicode
> characters to a sequence of regular and PUA Unicode characters where
> PUA codepoints(U+F700) are used for 'presentation forms'. To use this
> approach, all your glyphs have to be mapped. This works for Thai
> because most Thai truetype fonts have presentation forms in the U+F700
> block. In the long run, those fonts had better be converted to opentype
> fonts if not already.

It's in our plan. We're studying how pfaedit could do the job.
Err.. Since we're just beginning, any suggestion would be appreciated.

> Pango layout APIs support line wrapping.

I've started an experiment of enhancing Thai support in GTK+ by adopting
this API, as well as GTK+ IM module, for some time. It's part of Thai
Linux Working Group's libthai project:
  http://libthai.sourceforge.net/
The progress, however, is really slow, as it's a free-time job.
Libthai itself is at very alpha stage, but it could just get the job done,
anyway. The experiment includes:
  o pango-libthai bridge, which provides:
    - Pango Thai shaping engine
    - Pango Thai word break engine
  o gtk-im-libthai bridge, which provides:
    - GTK+ IM Module, with context-sensitive input sequence
      normalization
Doing a separate library does benefit for the case of Thai, as our
input/output methods are closely related. Doing so could prevent code
duplication in the Pango and GTK+ IM modules. And, if possible, Qt can
also share it.

And, thanks to GTK+ 2 modular design, we can experiment it as
third-party plug-ins, until it's stable enough.

Regards,
-Thep.
-- 
Theppitak Karoonboonyanan
http://linux.thai.net/thep/