Re: Arabic support

[Thamer Mahmoud <thamer.mahmoud@gmail.com>]

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>> From: Kenichi Handa <handa@m17n.org>
>> Date: Thu, 26 Aug 2010 10:10:05 +0900
>> 
>> I've just committed changes to trunk for Arabic shaping.  If
>> there're any Arabic users in this list, please check the
>> displaying of Arabic text.  On GNU/Linux system, you must
>> compile Emacs with libotf and m17n-lib (configure script
>> should detect them automatically).
>

Thanks for working on this. Here is my take:

* Attached are two screenshots showing the Arabic line from the HELLO
  file rendered by gedit and Emacs using the same font (Nazli-20 from
  ttf-farsiweb). Notice that in Emacs not all fonts have their LAM and
  ALIF properly replaced by the LAM-ALIF ligature. Also the diacritics
  (SHADDA) appears lower and less legible for the same font.

* The third attachment shows that when highlighting a region of an
  Arabic word, the cursor at the edges of the visible selection "breaks"
  the shaping and reshapes the characters around it into their isolated
  form. This creates a wave-effect of moving characters with some
  visible artifacts and bad indention issues.

* While the cursor is at a composed character (e.g., SEEN+SHADDA),
  pressing C-p moves point unexpectedly to the beginning of the current
  line.

* I do at least see one "trap" with C-p, although it is hard to
  reproduce. You can try moving 4 or 5 lines below the Arabic line in
  the HELLO file, then move upward using 4-5 C-p and get the cursor at
  the SEEN+SHADDA. After which any further C-p jumps between SEEN and
  LAM-ALIF, never going to the previous line.

* For those using Debian (Squeeze), I had to install not just the
  libm17n and libm17n-dev packages, but also m17n-db. It seems that the
  configure script doesn't detect or know about the status of (the
  Debian-specific) m17n-db.

Thanks again,
Thamer


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