Re: BUG #4714: Unicode Big5 Conversion

> > There is authoritative source for the Big5 encoding, but don't believe
> > that do help
> >
> >     http://www.cns11643.gov.tw/AIDB/encodings_en.do
> >
> > Skip the historical mess already done. we should focus on reality?
> >
> > brief events according time-line,
> >
> >     * BIG5 created, mostly by ETEN company, some others but not important now.
> >     * CNS Standard like 11643, Taiwan Government authority building in
> > mean time ...
> >     * Windows 3 showup, need Chinese ... pick not CNS but BIG5 ???
> > Code Page 950 born.
> >     * ETEN company add "ETen-extension 0xF9D6-0xF9FE" to work with IBM5550
> >     * Since Windows ME, CP950 add above mentioned 7 char. 0xF9D6-0xF9FE ONLY ???
> >     * Later Hong Kong add above 7 Char. plus some more symbol in
> > HKSCS-2004, and what you found is right.
> >     * WHAT A MESS !
> >
> > Focus on reality,
> > only mentioned 7 Char. I need to build into pgsql sources to compliant
> > with CP950, since few years ago.
>
> Ok, so Windows codepage 950 has those 7 characters, but not the other
> ETEN extended chars. I think that's a good enough reason to add those 7
> chars; we have 'win950' as an alias for big5 anyway.
>
> I'll go add those characters.

Be very careful not to break the standard defined by Unicode.
For example the glyph for 0xe7a281 == U+7881 is defined in page 43 of
http://unicode.org/charts/PDF/U4E00.pdf. So we need to make sure that the
particular kanji character defined in Big5 0xf9d6 has the same glyph
as the one defined in Unicode(U+7881). Same thing can be said to rest
of the proposed mapping.

>  {0xf9d6, 0xe7a281},
>  {0xf9d7, 0xe98ab9},
>  {0xf9d8, 0xe8a38f},
>  {0xf9d9, 0xe5a2bb},
>  {0xf9da, 0xe68192},
>  {0xf9db, 0xe7b2a7},
>  {0xf9dc, 0xe5abba},
--
Tatsuo Ishii
SRA OSS, Inc. Japan