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/* FriBidi - Library of BiDi algorithm
* Copyright (C) 1999 Dov Grobgeld
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef FRIBIDI_H
#define FRIBIDI_H
#include <glib.h>
#include "fribidi_types.h"
#include "fribidi_char_sets.h"
FriBidiCharType fribidi_get_type(FriBidiChar uch);
gboolean
fribidi_get_mirror_char(/* Input */
FriBidiChar ch,
/* Output */
FriBidiChar *mirrored_ch);
void
fribidi_set_debug(gboolean debug);
void fribidi_log2vis(/* input */
FriBidiChar *str,
gint len,
FriBidiCharType *pbase_dir,
/* output */
FriBidiChar *visual_str,
guint16 *position_L_to_V_list,
guint16 *position_V_to_L_list,
guint8 *embedding_level_list
);
void fribidi_log2vis_get_embedding_levels(
/* input */
FriBidiChar *str,
int len,
FriBidiCharType *pbase_dir,
/* output */
guint8 *embedding_level_list
);
/* fribidi_utils.c */
/*======================================================================
// fribidi_find_string_changes() finds the bounding box of the section
// of characters that need redrawing. It returns the start and the
// length of the section in the new string that needs redrawing.
//----------------------------------------------------------------------*/
void
fribidi_find_string_changes(/* input */
FriBidiChar *old_str,
int old_len,
FriBidiChar *new_str,
int new_len,
/* output */
int *change_start,
int *change_len
);
/*======================================================================
// The find_visual_ranges() function is used to convert between a
// continous span in either logical or visual space to a one, two or
// three discontinous spans in the other space. The function outputs
// the number of ranges needed to display the mapped range as
// well as the resolved ranges.
//
// The variable is_v2l_map indicates whether the position map is
// is in the direction of visual-to-logical. This information is
// needed in order to look up the correct character from the
// embedding_level_list which is assumed to be in logical order.
//
// This function is typically used to resolve a logical range to visual
// ranges e.g. to display the selection.
//
// Example:
// The selection is between logical characters 10 to 45. Calculate
// the corresponding visual selection(s):
//
// gint sel_span[2] = {10,45};
//
// fribidi_map_range(sel_span,
// TRUE,
// length,
// vis2log_map,
// embedding_levels,
// // output
// &num_vis_ranges,
// vis_ranges);
//
//----------------------------------------------------------------------*/
void
fribidi_map_range (gint span[2],
int len,
gboolean is_v2l_map,
guint16 *position_map,
guint8 *embedding_level_list,
/* output */
int *num_mapped_spans,
int spans[3][2]);
/*======================================================================
// fribidi_is_char_rtl() answers the question whether a character
// was resolved in the rtl direction. This simply involves asking
// if the embedding level for the character is odd.
//----------------------------------------------------------------------*/
gboolean
fribidi_is_char_rtl(guint8 *embedding_level_list,
FriBidiCharType base_dir,
int idx);
/*======================================================================
// fribidi_xpos_resolve() does the complicated translation of
// an x-coordinate, e.g. as received through a mouse press event,
// to the logical and the visual position the xcoordinate is closest
// to. It will also resolve the direction of the cursor according
// to the embedding level of the closest character.
//
// It does this through the following logics:
// Here are the different possibilities:
//
// Pointer => Log Pos Vis pos
//
// Before first vis char log_pos(vis=0)L 0
// After last vis char log_pos(vis=n-1)R n
// Within 1/2 width of vis char i log_pos(vis=i)L i
// Within last 1/2 width of vchar i log_pos(vis=i)R i+1
// Border between vis chars i,i+1 resolve! i+1
//
// Input:
// x_pos The pixel position to be resolved measured in pixels.
// x_offset The x_offset is the pixel position of the left side
// of the leftmost visual character.
// len The length of the embedding level, the vis2log and
// the char width arrays.
// base_dir The resolved base direction of the line.
// vis2log The vis2log mapping.
// x_position and the character widths. The position
// (x_pos-x_offset) is number of pixels from the left
// of logical character 0.
// char_widths Width in pixels of each character. Note that the
// widths should be provided in logical order.
//
// Output:
// res_log_pos Resolved logical position.
// res_vis_pos Resolved visual position
// res_cursor_x_pos The resolved pixel position to the left or
// the right of the character position x_pos.
// res_cursor_dir_is_rtl Whether the resolved dir of the character
// at position x_pos is rtl.
// res_attach_before Whether the x_pos is cutting the bounding
// box in such a way that the visual cursor should be
// be positioned before the following logical character.
// Note that in the bidi context, the positions "after
// a logical character" and "before the following logical
// character" is not necessarily the same. If x_pos is
// beyond the end of the line, res_attach_before is true.
//
//----------------------------------------------------------------------*/
void fribidi_xpos_resolve(gint x_pos,
gint x_offset,
gint len,
guint8 *embedding_level_list,
FriBidiCharType base_dir,
guint16 *vis2log,
gint16 *char_widths,
/* output */
gint *res_log_pos,
gint *res_vis_pos,
gint *res_cursor_x_pos,
gboolean *res_cursor_dir_is_rtl,
gboolean *res_attach_before
);
#endif /* FRIBIDI_H */
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