This is is FriBidi, a Free Implementation of the Unicode BiDi algorithm. Background ========== One of the missing links stopping the penetration of free software in Middle East is the lack of support for the Arabic and Hebrew alphabets. In order to have proper Arabic and Hebrew support, the BiDi algorithm should have been implemented. It is our hope that this library will stimulate more free software in the Middle Eastern countries. Audience ======== It is our hope that this library will stimulate the implementation of Hebrew and Arabic in lots of free software. Here is a small list of projects that would benifit from the use of the FriBidi library, but of course there are many more: Wine, Mozilla, Qt, KDE, lynx, OpenOffice. It may be interesting for you to know that Fribidi is already being used in projects like Gnome, GTK+, Pango, AbiWord, and Xterm. Downloading =========== The latest version of FriBidi may be found at: http://fribidi.sourceforge.net/ Building ======== See INSTALL for a description of how to build and install this library. Copyright ========= Fribidi is: Copyright (C) 1999,2000 Dov Grobgeld, and Copyright (C) 2001,2002 Behdad Esfahbod. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library, in a file named COPYING; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA For licensing issues, contact and . Implementation ============== The library implements the algorithm described in the "Unicode Standard Annex #9, The Bidirectional Algorithm", available at http://www.unicode.org/unicode/reports/tr9/. Fribidi has been tested exhaustively against the Unicode Reference Code, and due to our knowledge, it completely conforms to the specification, always producing the same result as the Reference Code. In the API we were inspired by the document "Bi-Di languages support - BiDi API propasal", http://www.langbox.com/AraMosaic/mozilla/BiDi_API.html, by Franck Portaneri which he wrote as a proposal for adding BiDi support to Mozilla. Internally, the library uses Unicode entirely. The character property function was automatically created from the Unicode property list document PropList.txt available from the Unicode FTP site. This means that every Unicode character is treated in strict accordance with the Unicode specification. The same is true for the mirroring of characters, which also works for all the characters listed as mirrorable in the the Unicode specification. Other character sets must be converted into Unicode before the library may be used. In order to use, e.g. iso8859-8, the function void fribidi_iso8859_8_to_unicode(guchar *s, /* output */ FriBidiChar *us) must be called which translates the guchar string *s to a unicode string. There is also a corresponding fribidi_unicode_to_iso8859_8 that may be called to convert the string back to iso8859_8 for output. The reordering of characters is done through the function: void fribidi_log2vis(/* input */ FriBidiChar *str, int len, FriBidiCharType *pbase_dir, /* output */ FriBidiChar *visual_str, gint *position_L_to_V_list, gint *position_V_to_L_list, gint8 *embedding_level_list ) where str is the Unicode input string len is the length of the unicode string pbase_dir is the input and output base direction. If base == FRIBIDI_TYPE_ON then fribidi_log2vis calculates the base direction on its own according to the BiDi algorithm. visual_str The reordered output unicode string. position_L_to_V_list Maps the positions in the logical string to positions in the visual string. position_V_to_L_list Maps the positions in the visual string to the positions in the logical string. embedding_level_list Returns the classification of each character. Even levels indicate LTR characters, and odd levels indicate RTL characters. The main use of this list is in interactive applications when the embedding e.g. level determines cursor display. In any of the output pointers == NULL, then that information is not calculated. How it looks like ================= Have a look at tests directory, to see some input and outputs, which CapRTL charset means that CAPITAL letters are right to left, and digits 6, 7, 8, 9 are Arabic digits, try 'fribidi --charsetdesc CapRTL' for the full description. Executable ========== There is also a command line utilitity called fribidi that loops over the text of a file and performs the BiDi algorithm on each line, also used for testing the algorithm. Run fribidi with the --help option to learn about usage. Bugs and comments ================= Report FriBidi bugs at: http://fribidi.sourceforge.net/bugs.php And send your comments to: fribidi-discuss@lists.sourceforge.net