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Purpose
=======
         
This extension is basically a wrapper for the FriBidi implementation
of the Unicode Bidi algorithm. The need for such an algorithm rises
from the bidirectional language usage  done by applications. 
Arabic/Hebrew embedded within English is such a case.

Usage
=====

 The only function used is fribidi_log2vis (logical [non-reversed] to visual [reversed]).
     Input: 
            1) The Logical string.
            2) Base direction of application. Possible values:
                 a) FRIBIDI_RTL  - right to left
                 b) FRIBIDI_LTR  - left to right
                 c) FRIBIDI_AUTO - autodetect the base direction
            3) The char code being used, which can be one of the following
               constants:
                 a) FRIBIDI_CHARSET_UTF8       (Unicode)
                 b) FRIBIDI_CHARSET_8859_6     (Arabic)
                 c) FRIBIDI_CHARSET_8859_8     (Hebrew)
                 d) FRIBIDI_CHARSET_CP1255     (Hebrew/Yiddish)
                 e) FRIBIDI_CHARSET_CP1256     (Arabic)
                 f) FRIBIDI_CHARSET_ISIRI_3342 (Persian)
                 g) FRIBIDI_CHARSET_CAP_RTL - Used for test purposes, will treat CAPS as non-English letetrs

Note: Currently, FriBidi supports the above Character Codes alone. 

      Output: A Visual string.


Compiling
=========== 
1) Static - ./configure --with-fribidi=base-directory-of-FriBidi-installation-path 
             (defaults to /usr/local).

2) dl - same, just add shared, to get .... --with-fribidi=shared,base....
  
Prerequisites
=============
1) FriBidi version 0.10.4 or later must be installed. Latest version can be obtained thru 
   http://fribidi.sourceforge.net/

Note
=====

The function fribidi_log2vis computes three more arrays which are currently not passed back as output.
These arrays are:
	1) mapping from the logical to the visual string.
	2) mapping from the visual to the logical string.
	3) embedding level of characters as figured out by the FriBidi algorithm.

The extension needs further implementation to support this. 
p.s. - If you don't understand this, you probably don't need it.