From c6c17b5175bb08f7a1f6ae782715ac53cbcabd3d Mon Sep 17 00:00:00 2001 From: Roozbeh Pournader Date: Wed, 8 Nov 2006 12:07:39 +0000 Subject: =?UTF-8?q?Bug=20350132=20=E2=80=93=20backspacing=20doesn't=20work?= =?UTF-8?q?=20properly=20for=20Arabic?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 2006-11-08 Roozbeh Pournader Bug 350132 – backspacing doesn't work properly for Arabic * modules/arabic/arabic-lang.c: Add more backspace_deletes_character cases. --- ChangeLog | 7 +++++++ modules/arabic/arabic-lang.c | 44 +++++++++++++++++++++++++++++++++++++++----- 2 files changed, 46 insertions(+), 5 deletions(-) diff --git a/ChangeLog b/ChangeLog index 5789fecb..53d385bf 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2006-11-08 Roozbeh Pournader + + Bug 350132 – backspacing doesn't work properly for Arabic + + * modules/arabic/arabic-lang.c: Add more backspace_deletes_character + cases. + 2006-11-08 Behdad Esfahbod * pango/pango-layout.c (pango_layout_move_cursor_visually): Don't diff --git a/modules/arabic/arabic-lang.c b/modules/arabic/arabic-lang.c index 0bf0d52c..4d458442 100644 --- a/modules/arabic/arabic-lang.c +++ b/modules/arabic/arabic-lang.c @@ -1,8 +1,10 @@ /* Pango - * arabic-fc.h: + * arabic-lang.c: * * Copyright (C) 2006 Red Hat Software - * Author: Behdad Esfahbod + * Copyright (C) 2006 Sharif FarsiWeb, Inc. + * Authors: Behdad Esfahbod + * Roozbeh Pournader * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public @@ -47,6 +49,27 @@ static PangoEngineInfo script_engines[] = { }; +#define ALEF_WITH_MADDA_ABOVE 0x0622 +#define YEH_WITH_HAMZA_ABOVE 0x0626 +#define ALEF 0x0627 +#define WAW 0x0648 +#define YEH 0x064A + +#define MADDAH_ABOVE 0x0653 +#define HAMZA_ABOVE 0x0654 +#define HAMZA_BELOW 0x0655 + +/* + * Arabic characters with canonical decompositions that are not just + * ligatures. The characters U+06C0, U+06C2, and U+06D3 are intentionally + * excluded as they are marked as "not an independent letter" in Unicode + * Character Database's NamesList.txt + */ +#define IS_COMPOSITE(c) (ALEF_WITH_MADDA_ABOVE <= (c) && (c) <= YEH_WITH_HAMZA_ABOVE) + +/* If a character is the second part of a composite Arabic character with an Alef */ +#define IS_COMPOSITE_WITH_ALEF(c) (MADDAH_ABOVE <= (c) && (c) <= HAMZA_BELOW) + static void arabic_engine_break (PangoEngineLang *engine, const char *text, @@ -70,11 +93,22 @@ arabic_engine_break (PangoEngineLang *engine, this_wc = g_utf8_get_char (p); /* - * Unset backspace_deletes_character for various combinations: + * Unset backspace_deletes_character for various combinations. + * + * A few more combinations may need to be handled here, but are not + * handled yet, as expectations of users is not known or may differ + * among different languages or users: + * some letters combined with U+0658 ARABIC MARK NOON GHUNNA; + * combinations considered one letter in Azerbaijani (WAW+SUKUN and + * FARSI_YEH+HAMZA_ABOVE); combinations of YEH and ALEF_MAKSURA with + * HAMZA_BELOW (Qur'anic); TATWEEL+HAMZA_ABOVE (Qur'anic). + * + * FIXME: Ordering these in some other way may lower the time spent here, or not. */ if (G_UNLIKELY ( - this_wc == 0x0622 /* ARABIC LETTER ALEF WITH MADDA ABOVE */ || - (prev_wc == 0x0627 /* ARABIC LETTER ALEF */ && this_wc == 0x0653 /* ARABIC MADDAH ABOVE */) + IS_COMPOSITE (this_wc) || + (prev_wc == ALEF && IS_COMPOSITE_WITH_ALEF (this_wc)) || + (this_wc == HAMZA_ABOVE && (prev_wc == WAW || prev_wc == YEH)) )) attrs[i+1].backspace_deletes_character = FALSE; } -- cgit v1.2.1