[css3-text] Thai line breaking rules from Koji Ishii on 2011-02-07 (www-style@w3.org from February 2011) (original) (raw)

I had a meeting with ILCAA, Research Institute for Languages and Cultures of Asia and Africa[1] in Tokyo. Minegishi-san at ILCAA presented his idea for the issue currently mentioned in the CSS3 Text spec[2]:

Additionally, some guidance should be provided on how to break or not break Southeast Asian in the absence of a dictionary.

Here's his draft of the simple line breaking rules in the absence of a dictionary for Thai scripts. Any corrections, and/or opinions whether to include this in the spec or not would be appreciated.

Thai character groups are based on TIS 620-2553 as written in Unicode spec[3]. Consonants: U+0E01-0E2E

Line breaks are prohibited between:

• Any and U+0E2F
• and [U+0E30-0E3A]
• [U+0E31, U+0E3A, U+0E40-0E44] and
• U+0E3F THAI Currency Symbol BAHT and digits
• [U+0E24, U+0E26] and U+0E45
• [U+0E50-0E59] and [U+0E50-0E59]
• Any and U+0E5A

Following rules are also presented, but they are Unicode Lm or Mn category and therefore I suspect that UAX#29 Unicode Text Segmentation should cover these rules.

• Any and U+0E46
• and [U+0E47]
• ( or [U+0E34-0E39]) and [U+0E48-0E4B]
• ( or [U+0E34-0E39]) and U+0E4C
• and [U+0E4D-0E4E]

[1] http://www.aa.tufs.ac.jp/en [2] http://dev.w3.org/csswg/css3-text/#line-breaking [3] http://unicode.org/charts/PDF/U0E00.pdf [4] http://unicode.org/reports/tr29/

Regards, Koji

Received on Monday, 7 February 2011 03:46:40 UTC