jammy (3) fribidi_reorder_line.3.gz

NAME

       fribidi_reorder_line - reorder a line of logical string to visual

SYNOPSIS

       #include <fribidi.h>

       extern FriBidiLevel fribidi_reorder_line
       (
            FriBidiFlags flags,
            const FriBidiCharType *bidi_types,
            const FriBidiStrIndex len,
            const FriBidiStrIndex off,
            const FriBidiParType base_dir,
            FriBidiLevel *embedding_levels,
            FriBidiChar *visual_str,
            FriBidiStrIndex *map
       );

PARAMETERS

       FriBidiFlags flags
              Reorder flags.

       const FriBidiCharType *bidi_types
              Input list of bidi types as returned by fribidi_get_bidi_types().

              Since there are 23 possible values for a const FriBidiCharType, they are not all listed here.

       const FriBidiStrIndex len
              Input length of the line.

       const FriBidiStrIndex off
              Input offset of the beginning of the line in the paragraph.

       const FriBidiParType base_dir
              Resolved paragraph base direction.

              Possible values for a const FriBidiParType are as follows:
              FRIBIDI_PAR_LTR   Left-To-Right paragraph.
              FRIBIDI_PAR_RTL   Right-To-Left paragraph.
              FRIBIDI_PAR_ON    DirectiOn-Neutral paragraph.
              FRIBIDI_PAR_WLTR  Weak Left To Right paragraph.
              FRIBIDI_PAR_WRTL  Weak Right To Left paragraph.

       FriBidiLevel *embedding_levels
              Input list of embedding levels, as returned by fribidi_get_par_embedding_levels.

       FriBidiChar *visual_str
              Visual string to reorder.

       FriBidiStrIndex *map
              A map of string indices which is reordered to reflect where each glyph ends up.

DESCRIPTION

       This  function  reorders  the  characters  in  a  line  of text from logical to final visual order.  This
       function implements part 4 of rule L1, and rules  L2  and  L3  of  the  Unicode  Bidirectional  Algorithm
       available at http://www.unicode.org/reports/tr9/#Reordering_Resolved_Levels.

       As a side effect it also sets position maps if not NULL.

       You   should   provide   the   resolved   paragraph   direction   and   embedding   levels   as   set  by
       fribidi_get_par_embedding_levels().  Also note that the embedding levels may change a bit.  To be  exact,
       the embedding level of any sequence of white space at the end of line is reset to the paragraph embedding
       level (That is part 4 of rule L1).

       Note that the bidi types and embedding levels are not reordered.  You can reorder these  (or  any  other)
       arrays  using  the  map  later.  The user is responsible to initialize map to something sensible, like an
       identity mapping, or pass NULL if no map is needed.

       There is an optional part to this function, which is whether non-spacing marks for right-to-left parts of
       the  text  should  be  reordered  to  come after their base characters in the visual string or not.  Most
       rendering engines expect this behavior, but console-based systems for example do not like  it.   This  is
       controlled by the FRIBIDI_FLAG_REORDER_NSM flag.  The flag is on in FRIBIDI_FLAGS_DEFAULT.

RETURNS

       Maximum  level found in this line plus one, or zero if any error occurred (memory allocation failure most
       probably).

SEE ALSO

       fribidi_shape_arabic(3),      fribidi_get_par_direction(3),       fribidi_get_par_embedding_levels_ex(3),
       fribidi_get_bidi_type(3),            fribidi_get_bidi_types(3),            fribidi_get_bidi_type_name(3),
       fribidi_debug_status(3),               fribidi_set_debug(3),               fribidi_charset_to_unicode(3),
       fribidi_unicode_to_charset(3),           fribidi_parse_charset(3),           fribidi_mirroring_status(3),
       fribidi_set_mirroring(3),           fribidi_reorder_nsm_status(3),            fribidi_set_reorder_nsm(3),
       fribidi_log2vis_get_embedding_levels(3),        fribidi_get_type(3),        fribidi_get_type_internal(3),
       fribidi_get_par_embedding_levels(3),         fribidi_join_arabic(3),         fribidi_get_joining_type(3),
       fribidi_get_joining_types(3),        fribidi_get_joining_type_name(3),        fribidi_get_mirror_char(3),
       fribidi_shape_mirroring(3),   fribidi_get_bracket(3),   fribidi_get_bracket_types(3),   fribidi_shape(3),
       fribidi_remove_bidi_marks(3)