src/hb-ot-layout.h

   1 /*
   2  * Copyright © 2007,2008,2009  Red Hat, Inc.
   3  *
   4  *  This is part of HarfBuzz, a text shaping library.
   5  *
   6  * Permission is hereby granted, without written agreement and without
   7  * license or royalty fees, to use, copy, modify, and distribute this
   8  * software and its documentation for any purpose, provided that the
   9  * above copyright notice and the following two paragraphs appear in
  10  * all copies of this software.
  11  *
  12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  16  * DAMAGE.
  17  *
  18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  23  *
  24  * Red Hat Author(s): Behdad Esfahbod
  25  */
  26
  27 #ifndef HB_OT_H_IN
  28 #error "Include <hb-ot.h> instead."
  29 #endif
  30
  31 #ifndef HB_OT_LAYOUT_H
  32 #define HB_OT_LAYOUT_H
  33
  34 #include "hb.h"
  35
  36 #include "hb-ot-tag.h"
  37
  38 HB_BEGIN_DECLS
  39
  40
  41 #define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
  42 #define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
  43 #define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
  44
  45
  46 /*
  47  * GDEF
  48  */
  49
  50 hb_bool_t
  51 hb_ot_layout_has_glyph_classes (hb_face_t *face);
  52
  53 /* Not that useful.  Provides list of attach points for a glyph that a
  54  * client may want to cache */
  55 unsigned int
  56 hb_ot_layout_get_attach_points (hb_face_t      *face,
  57                                 hb_codepoint_t  glyph,
  58                                 unsigned int    start_offset,
  59                                 unsigned int   *point_count /* IN/OUT */,
  60                                 unsigned int   *point_array /* OUT */);
  61
  62 /* Ligature caret positions */
  63 unsigned int
  64 hb_ot_layout_get_ligature_carets (hb_font_t      *font,
  65                                   hb_direction_t  direction,
  66                                   hb_codepoint_t  glyph,
  67                                   unsigned int    start_offset,
  68                                   unsigned int   *caret_count /* IN/OUT */,
  69                                   hb_position_t  *caret_array /* OUT */);
  70
  71
  72 /*
  73  * GSUB/GPOS feature query and enumeration interface
  74  */
  75
  76 #define HB_OT_LAYOUT_NO_SCRIPT_INDEX            ((unsigned int) 0xFFFF)
  77 #define HB_OT_LAYOUT_NO_FEATURE_INDEX           ((unsigned int) 0xFFFF)
  78 #define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX     ((unsigned int) 0xFFFF)
  79
  80 unsigned int
  81 hb_ot_layout_table_get_script_tags (hb_face_t    *face,
  82                                     hb_tag_t      table_tag,
  83                                     unsigned int  start_offset,
  84                                     unsigned int *script_count /* IN/OUT */,
  85                                     hb_tag_t     *script_tags /* OUT */);
  86
  87 hb_bool_t
  88 hb_ot_layout_table_find_script (hb_face_t    *face,
  89                                 hb_tag_t      table_tag,
  90                                 hb_tag_t      script_tag,
  91                                 unsigned int *script_index);
  92
  93 /* Like find_script, but takes zero-terminated array of scripts to test */
  94 hb_bool_t
  95 hb_ot_layout_table_choose_script (hb_face_t      *face,
  96                                   hb_tag_t        table_tag,
  97                                   const hb_tag_t *script_tags,
  98                                   unsigned int   *script_index,
  99                                   hb_tag_t       *chosen_script);
 100
 101 unsigned int
 102 hb_ot_layout_table_get_feature_tags (hb_face_t    *face,
 103                                      hb_tag_t      table_tag,
 104                                      unsigned int  start_offset,
 105                                      unsigned int *feature_count /* IN/OUT */,
 106                                      hb_tag_t     *feature_tags /* OUT */);
 107
 108 unsigned int
 109 hb_ot_layout_script_get_language_tags (hb_face_t    *face,
 110                                        hb_tag_t      table_tag,
 111                                        unsigned int  script_index,
 112                                        unsigned int  start_offset,
 113                                        unsigned int *language_count /* IN/OUT */,
 114                                        hb_tag_t     *language_tags /* OUT */);
 115
 116 hb_bool_t
 117 hb_ot_layout_script_find_language (hb_face_t    *face,
 118                                    hb_tag_t      table_tag,
 119                                    unsigned int  script_index,
 120                                    hb_tag_t      language_tag,
 121                                    unsigned int *language_index);
 122
 123 hb_bool_t
 124 hb_ot_layout_language_get_required_feature_index (hb_face_t    *face,
 125                                                   hb_tag_t      table_tag,
 126                                                   unsigned int  script_index,
 127                                                   unsigned int  language_index,
 128                                                   unsigned int *feature_index);
 129
 130 unsigned int
 131 hb_ot_layout_language_get_feature_indexes (hb_face_t    *face,
 132                                            hb_tag_t      table_tag,
 133                                            unsigned int  script_index,
 134                                            unsigned int  language_index,
 135                                            unsigned int  start_offset,
 136                                            unsigned int *feature_count /* IN/OUT */,
 137                                            unsigned int *feature_indexes /* OUT */);
 138
 139 unsigned int
 140 hb_ot_layout_language_get_feature_tags (hb_face_t    *face,
 141                                         hb_tag_t      table_tag,
 142                                         unsigned int  script_index,
 143                                         unsigned int  language_index,
 144                                         unsigned int  start_offset,
 145                                         unsigned int *feature_count /* IN/OUT */,
 146                                         hb_tag_t     *feature_tags /* OUT */);
 147
 148 hb_bool_t
 149 hb_ot_layout_language_find_feature (hb_face_t    *face,
 150                                     hb_tag_t      table_tag,
 151                                     unsigned int  script_index,
 152                                     unsigned int  language_index,
 153                                     hb_tag_t      feature_tag,
 154                                     unsigned int *feature_index);
 155
 156 unsigned int
 157 hb_ot_layout_feature_get_lookup_indexes (hb_face_t    *face,
 158                                          hb_tag_t      table_tag,
 159                                          unsigned int  feature_index,
 160                                          unsigned int  start_offset,
 161                                          unsigned int *lookup_count /* IN/OUT */,
 162                                          unsigned int *lookup_indexes /* OUT */);
 163
 164
 165 /*
 166  * GSUB
 167  */
 168
 169 hb_bool_t
 170 hb_ot_layout_has_substitution (hb_face_t *face);
 171
 172 hb_bool_t
 173 hb_ot_layout_would_substitute_lookup (hb_face_t            *face,
 174                                       const hb_codepoint_t *glyphs,
 175                                       unsigned int          glyphs_length,
 176                                       unsigned int          lookup_index);
 177
 178 void
 179 hb_ot_layout_substitute_closure_lookup (hb_face_t    *face,
 180                                         hb_set_t     *glyphs,
 181                                         unsigned int  lookup_index);
 182
 183 /*
 184  * GPOS
 185  */
 186
 187 hb_bool_t
 188 hb_ot_layout_has_positioning (hb_face_t *face);
 189
 190
 191 HB_END_DECLS
 192
 193 #endif /* HB_OT_LAYOUT_H */