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- /* FriBidi
- * fribidi-bidi.h - bidirectional algorithm
- *
- * Authors:
- * Behdad Esfahbod, 2001, 2002, 2004
- * Dov Grobgeld, 1999, 2000
- *
- * Copyright (C) 2004 Sharif FarsiWeb, Inc
- * Copyright (C) 2001,2002 Behdad Esfahbod
- * Copyright (C) 1999,2000 Dov Grobgeld
- *
- * 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., 51 Franklin Street, Fifth Floor,
- * Boston, MA 02110-1301, USA
- *
- * For licensing issues, contact <fribidi.license@gmail.com>.
- */
- #ifndef _FRIBIDI_BIDI_H
- #define _FRIBIDI_BIDI_H
- #include "fribidi-common.h"
- #include "fribidi-types.h"
- #include "fribidi-flags.h"
- #include "fribidi-bidi-types.h"
- #include "fribidi-begindecls.h"
- /* fribidi_get_par_direction - get base paragraph direction
- *
- * This function finds the base direction of a single paragraph,
- * as defined by rule P2 of the Unicode Bidirectional Algorithm available at
- * http://www.unicode.org/reports/tr9/#P2.
- *
- * You typically do not need this function as
- * fribidi_get_par_embedding_levels() knows how to compute base direction
- * itself, but you may need this to implement a more sophisticated paragraph
- * direction handling. Note that you can pass more than a paragraph to this
- * function and the direction of the first non-neutral paragraph is returned,
- * which is a very good heuristic to set direction of the neutral paragraphs
- * at the beginning of text. For other neutral paragraphs, you better use the
- * direction of the previous paragraph.
- *
- * Returns: Base pargraph direction. No weak paragraph direction is returned,
- * only LTR, RTL, or ON.
- */
- FRIBIDI_ENTRY FriBidiParType fribidi_get_par_direction (
- const FriBidiCharType *bidi_types, /* input list of bidi types as returned by
- fribidi_get_bidi_types() */
- const FriBidiStrIndex len /* input string length */
- );
- /* fribidi_get_par_embedding_levels_ex - get bidi embedding levels of a paragraph
- *
- * This function finds the bidi embedding levels of a single paragraph,
- * as defined by the Unicode Bidirectional Algorithm available at
- * http://www.unicode.org/reports/tr9/. This function implements rules P2 to
- * I1 inclusive, and parts 1 to 3 of L1, except for rule X9 which is
- * implemented in fribidi_remove_bidi_marks(). Part 4 of L1 is implemented
- * in fribidi_reorder_line().
- *
- * There are a few macros defined in fribidi-bidi-types.h to work with this
- * embedding levels.
- *
- * Returns: Maximum level found plus one, or zero if any error occurred
- * (memory allocation failure most probably).
- */
- FRIBIDI_ENTRY FriBidiLevel
- fribidi_get_par_embedding_levels_ex (
- const FriBidiCharType *bidi_types, /* input list of bidi types as returned by
- fribidi_get_bidi_types() */
- const FriBidiBracketType *bracket_types, /* input list of bracket types as returned by
- fribidi_get_bracket_types() */
- const FriBidiStrIndex len, /* input string length of the paragraph */
- FriBidiParType *pbase_dir, /* requested and resolved paragraph
- * base direction */
- FriBidiLevel *embedding_levels /* output list of embedding levels */
- ) FRIBIDI_GNUC_WARN_UNUSED;
- /* fribidi_reorder_line - reorder a line of logical string to visual
- *
- * 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).
- */
- FRIBIDI_ENTRY FriBidiLevel fribidi_reorder_line (
- FriBidiFlags flags, /* reorder flags */
- const FriBidiCharType *bidi_types, /* input list of bidi types as returned by
- fribidi_get_bidi_types() */
- 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 */
- 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. */
- ) FRIBIDI_GNUC_WARN_UNUSED;
- #include "fribidi-enddecls.h"
- #endif /* !_FRIBIDI_BIDI_H */
- /* Editor directions:
- * vim:textwidth=78:tabstop=8:shiftwidth=2:autoindent:cindent
- */
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