src/hb-ot-layout.h

   1 /*
   2  * Copyright (C) 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_LAYOUT_H
  28 #define HB_OT_LAYOUT_H
  29
  30 #include "hb-common.h"
  31 #include "hb-buffer.h"
  32 #include "hb-font.h"
  33
  34 #include "hb-ot-tag.h"
  35
  36 HB_BEGIN_DECLS
  37
  38
  39 #define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
  40 #define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
  41 #define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
  42
  43 /*
  44  * GDEF
  45  */
  46
  47 typedef enum {
  48   HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED = 0x0000,
  49   HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH   = 0x0002,
  50   HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE     = 0x0004,
  51   HB_OT_LAYOUT_GLYPH_CLASS_MARK         = 0x0008,
  52   HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT    = 0x0010
  53 } hb_ot_layout_glyph_class_t;
  54
  55 /* XXX These should eventually be removed as we move synthesized glyph
  56  * classes in harfbuzz. */
  57
  58 hb_bool_t
  59 hb_ot_layout_has_glyph_classes (hb_face_t *face);
  60
  61 hb_ot_layout_glyph_class_t
  62 hb_ot_layout_get_glyph_class (hb_face_t      *face,
  63                               hb_codepoint_t  glyph);
  64
  65 void
  66 hb_ot_layout_set_glyph_class (hb_face_t                 *face,
  67                               hb_codepoint_t             glyph,
  68                               hb_ot_layout_glyph_class_t klass);
  69
  70 void
  71 hb_ot_layout_build_glyph_classes (hb_face_t      *face,
  72                                   hb_codepoint_t *glyphs,
  73                                   unsigned char  *klasses,
  74                                   uint16_t        count);
  75
  76 /* Not that useful.  Provides list of attach points for a glyph that a
  77  * client may want to cache */
  78 unsigned int
  79 hb_ot_layout_get_attach_points (hb_face_t      *face,
  80                                 hb_codepoint_t  glyph,
  81                                 unsigned int    start_offset,
  82                                 unsigned int   *point_count /* IN/OUT */,
  83                                 unsigned int   *point_array /* OUT */);
  84
  85 /* Ligature caret positions */
  86 unsigned int
  87 hb_ot_layout_get_ligature_carets (hb_font_t      *font,
  88                                   hb_face_t      *face,
  89                                   hb_direction_t  direction,
  90                                   hb_codepoint_t  glyph,
  91                                   unsigned int    start_offset,
  92                                   unsigned int   *caret_count /* IN/OUT */,
  93                                   int            *caret_array /* OUT */);
  94
  95
  96 /*
  97  * GSUB/GPOS feature query and enumeration interface
  98  */
  99
 100 #define HB_OT_LAYOUT_NO_SCRIPT_INDEX            ((unsigned int) 0xFFFF)
 101 #define HB_OT_LAYOUT_NO_FEATURE_INDEX           ((unsigned int) 0xFFFF)
 102 #define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX     ((unsigned int) 0xFFFF)
 103
 104 unsigned int
 105 hb_ot_layout_table_get_script_tags (hb_face_t    *face,
 106                                     hb_tag_t      table_tag,
 107                                     unsigned int  start_offset,
 108                                     unsigned int *script_count /* IN/OUT */,
 109                                     hb_tag_t     *script_tags /* OUT */);
 110
 111 hb_bool_t
 112 hb_ot_layout_table_find_script (hb_face_t    *face,
 113                                 hb_tag_t      table_tag,
 114                                 hb_tag_t      script_tag,
 115                                 unsigned int *script_index);
 116
 117 /* Like find_script, but takes zero-terminated array of scripts to test */
 118 hb_bool_t
 119 hb_ot_layout_table_choose_script (hb_face_t      *face,
 120                                   hb_tag_t        table_tag,
 121                                   const hb_tag_t *script_tags,
 122                                   unsigned int   *script_index);
 123
 124 unsigned int
 125 hb_ot_layout_table_get_feature_tags (hb_face_t    *face,
 126                                      hb_tag_t      table_tag,
 127                                      unsigned int  start_offset,
 128                                      unsigned int *feature_count /* IN/OUT */,
 129                                      hb_tag_t     *feature_tags /* OUT */);
 130
 131 unsigned int
 132 hb_ot_layout_script_get_language_tags (hb_face_t    *face,
 133                                        hb_tag_t      table_tag,
 134                                        unsigned int  script_index,
 135                                        unsigned int  start_offset,
 136                                        unsigned int *language_count /* IN/OUT */,
 137                                        hb_tag_t     *language_tags /* OUT */);
 138
 139 hb_bool_t
 140 hb_ot_layout_script_find_language (hb_face_t    *face,
 141                                    hb_tag_t      table_tag,
 142                                    unsigned int  script_index,
 143                                    hb_tag_t      language_tag,
 144                                    unsigned int *language_index);
 145
 146 hb_bool_t
 147 hb_ot_layout_language_get_required_feature_index (hb_face_t    *face,
 148                                                   hb_tag_t      table_tag,
 149                                                   unsigned int  script_index,
 150                                                   unsigned int  language_index,
 151                                                   unsigned int *feature_index);
 152
 153 unsigned int
 154 hb_ot_layout_language_get_feature_indexes (hb_face_t    *face,
 155                                            hb_tag_t      table_tag,
 156                                            unsigned int  script_index,
 157                                            unsigned int  language_index,
 158                                            unsigned int  start_offset,
 159                                            unsigned int *feature_count /* IN/OUT */,
 160                                            unsigned int *feature_indexes /* OUT */);
 161
 162 unsigned int
 163 hb_ot_layout_language_get_feature_tags (hb_face_t    *face,
 164                                         hb_tag_t      table_tag,
 165                                         unsigned int  script_index,
 166                                         unsigned int  language_index,
 167                                         unsigned int  start_offset,
 168                                         unsigned int *feature_count /* IN/OUT */,
 169                                         hb_tag_t     *feature_tags /* OUT */);
 170
 171 hb_bool_t
 172 hb_ot_layout_language_find_feature (hb_face_t    *face,
 173                                     hb_tag_t      table_tag,
 174                                     unsigned int  script_index,
 175                                     unsigned int  language_index,
 176                                     hb_tag_t      feature_tag,
 177                                     unsigned int *feature_index);
 178
 179 unsigned int
 180 hb_ot_layout_feature_get_lookup_indexes (hb_face_t    *face,
 181                                          hb_tag_t      table_tag,
 182                                          unsigned int  feature_index,
 183                                          unsigned int  start_offset,
 184                                          unsigned int *lookup_count /* IN/OUT */,
 185                                          unsigned int *lookup_indexes /* OUT */);
 186
 187
 188 /*
 189  * GSUB
 190  */
 191
 192 hb_bool_t
 193 hb_ot_layout_has_substitution (hb_face_t *face);
 194
 195 hb_bool_t
 196 hb_ot_layout_substitute_lookup (hb_face_t    *face,
 197                                 hb_buffer_t  *buffer,
 198                                 unsigned int  lookup_index,
 199                                 hb_mask_t     mask);
 200
 201 /*
 202  * GPOS
 203  */
 204
 205 hb_bool_t
 206 hb_ot_layout_has_positioning (hb_face_t *face);
 207
 208 hb_bool_t
 209 hb_ot_layout_position_lookup (hb_font_t    *font,
 210                               hb_face_t    *face,
 211                               hb_buffer_t  *buffer,
 212                               unsigned int  lookup_index,
 213                               hb_mask_t     mask);
 214
 215 /* Should be called after all the position_lookup's are done */
 216 void
 217 hb_ot_layout_position_finish (hb_font_t    *font,
 218                               hb_face_t    *face,
 219                               hb_buffer_t  *buffer);
 220
 221
 222 HB_END_DECLS
 223
 224 #endif /* HB_OT_LAYOUT_H */