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      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-name.h"
     37 
     38 HB_BEGIN_DECLS
     39 
     40 
     41 #define HB_OT_TAG_BASE HB_TAG('B','A','S','E')
     42 #define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
     43 #define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
     44 #define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
     45 #define HB_OT_TAG_JSTF HB_TAG('J','S','T','F')
     46 
     47 
     48 /*
     49  * Script & Language tags.
     50  */
     51 
     52 #define HB_OT_TAG_DEFAULT_SCRIPT	HB_TAG ('D', 'F', 'L', 'T')
     53 #define HB_OT_TAG_DEFAULT_LANGUAGE	HB_TAG ('d', 'f', 'l', 't')
     54 
     55 /**
     56  * HB_OT_MAX_TAGS_PER_SCRIPT:
     57  *
     58  * Since: 2.0.0
     59  **/
     60 #define HB_OT_MAX_TAGS_PER_SCRIPT	3u
     61 /**
     62  * HB_OT_MAX_TAGS_PER_LANGUAGE:
     63  *
     64  * Since: 2.0.0
     65  **/
     66 #define HB_OT_MAX_TAGS_PER_LANGUAGE	3u
     67 
     68 HB_EXTERN void
     69 hb_ot_tags_from_script_and_language (hb_script_t   script,
     70 				     hb_language_t language,
     71 				     unsigned int *script_count /* IN/OUT */,
     72 				     hb_tag_t     *script_tags /* OUT */,
     73 				     unsigned int *language_count /* IN/OUT */,
     74 				     hb_tag_t     *language_tags /* OUT */);
     75 
     76 HB_EXTERN hb_script_t
     77 hb_ot_tag_to_script (hb_tag_t tag);
     78 
     79 HB_EXTERN hb_language_t
     80 hb_ot_tag_to_language (hb_tag_t tag);
     81 
     82 HB_EXTERN void
     83 hb_ot_tags_to_script_and_language (hb_tag_t       script_tag,
     84 				   hb_tag_t       language_tag,
     85 				   hb_script_t   *script /* OUT */,
     86 				   hb_language_t *language /* OUT */);
     87 
     88 
     89 /*
     90  * GDEF
     91  */
     92 
     93 HB_EXTERN hb_bool_t
     94 hb_ot_layout_has_glyph_classes (hb_face_t *face);
     95 
     96 typedef enum {
     97   HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED	= 0,
     98   HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH	= 1,
     99   HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE	= 2,
    100   HB_OT_LAYOUT_GLYPH_CLASS_MARK		= 3,
    101   HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT	= 4
    102 } hb_ot_layout_glyph_class_t;
    103 
    104 HB_EXTERN hb_ot_layout_glyph_class_t
    105 hb_ot_layout_get_glyph_class (hb_face_t      *face,
    106 			      hb_codepoint_t  glyph);
    107 
    108 HB_EXTERN void
    109 hb_ot_layout_get_glyphs_in_class (hb_face_t                  *face,
    110 				  hb_ot_layout_glyph_class_t  klass,
    111 				  hb_set_t                   *glyphs /* OUT */);
    112 
    113 
    114 /* Not that useful.  Provides list of attach points for a glyph that a
    115  * client may want to cache */
    116 HB_EXTERN unsigned int
    117 hb_ot_layout_get_attach_points (hb_face_t      *face,
    118 				hb_codepoint_t  glyph,
    119 				unsigned int    start_offset,
    120 				unsigned int   *point_count /* IN/OUT */,
    121 				unsigned int   *point_array /* OUT */);
    122 
    123 /* Ligature caret positions */
    124 HB_EXTERN unsigned int
    125 hb_ot_layout_get_ligature_carets (hb_font_t      *font,
    126 				  hb_direction_t  direction,
    127 				  hb_codepoint_t  glyph,
    128 				  unsigned int    start_offset,
    129 				  unsigned int   *caret_count /* IN/OUT */,
    130 				  hb_position_t  *caret_array /* OUT */);
    131 
    132 
    133 /*
    134  * GSUB/GPOS feature query and enumeration interface
    135  */
    136 
    137 #define HB_OT_LAYOUT_NO_SCRIPT_INDEX		0xFFFFu
    138 #define HB_OT_LAYOUT_NO_FEATURE_INDEX		0xFFFFu
    139 #define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX	0xFFFFu
    140 #define HB_OT_LAYOUT_NO_VARIATIONS_INDEX	0xFFFFFFFFu
    141 
    142 HB_EXTERN unsigned int
    143 hb_ot_layout_table_get_script_tags (hb_face_t    *face,
    144 				    hb_tag_t      table_tag,
    145 				    unsigned int  start_offset,
    146 				    unsigned int *script_count /* IN/OUT */,
    147 				    hb_tag_t     *script_tags /* OUT */);
    148 
    149 HB_EXTERN hb_bool_t
    150 hb_ot_layout_table_find_script (hb_face_t    *face,
    151 				hb_tag_t      table_tag,
    152 				hb_tag_t      script_tag,
    153 				unsigned int *script_index);
    154 
    155 HB_EXTERN hb_bool_t
    156 hb_ot_layout_table_select_script (hb_face_t      *face,
    157 				  hb_tag_t        table_tag,
    158 				  unsigned int    script_count,
    159 				  const hb_tag_t *script_tags,
    160 				  unsigned int   *script_index /* OUT */,
    161 				  hb_tag_t       *chosen_script /* OUT */);
    162 
    163 HB_EXTERN unsigned int
    164 hb_ot_layout_table_get_feature_tags (hb_face_t    *face,
    165 				     hb_tag_t      table_tag,
    166 				     unsigned int  start_offset,
    167 				     unsigned int *feature_count /* IN/OUT */,
    168 				     hb_tag_t     *feature_tags /* OUT */);
    169 
    170 HB_EXTERN unsigned int
    171 hb_ot_layout_script_get_language_tags (hb_face_t    *face,
    172 				       hb_tag_t      table_tag,
    173 				       unsigned int  script_index,
    174 				       unsigned int  start_offset,
    175 				       unsigned int *language_count /* IN/OUT */,
    176 				       hb_tag_t     *language_tags /* OUT */);
    177 
    178 HB_EXTERN hb_bool_t
    179 hb_ot_layout_script_select_language (hb_face_t      *face,
    180 				     hb_tag_t        table_tag,
    181 				     unsigned int    script_index,
    182 				     unsigned int    language_count,
    183 				     const hb_tag_t *language_tags,
    184 				     unsigned int   *language_index /* OUT */);
    185 
    186 HB_EXTERN hb_bool_t
    187 hb_ot_layout_language_get_required_feature_index (hb_face_t    *face,
    188 						  hb_tag_t      table_tag,
    189 						  unsigned int  script_index,
    190 						  unsigned int  language_index,
    191 						  unsigned int *feature_index);
    192 
    193 HB_EXTERN hb_bool_t
    194 hb_ot_layout_language_get_required_feature (hb_face_t    *face,
    195 					    hb_tag_t      table_tag,
    196 					    unsigned int  script_index,
    197 					    unsigned int  language_index,
    198 					    unsigned int *feature_index,
    199 					    hb_tag_t     *feature_tag);
    200 
    201 HB_EXTERN unsigned int
    202 hb_ot_layout_language_get_feature_indexes (hb_face_t    *face,
    203 					   hb_tag_t      table_tag,
    204 					   unsigned int  script_index,
    205 					   unsigned int  language_index,
    206 					   unsigned int  start_offset,
    207 					   unsigned int *feature_count /* IN/OUT */,
    208 					   unsigned int *feature_indexes /* OUT */);
    209 
    210 HB_EXTERN unsigned int
    211 hb_ot_layout_language_get_feature_tags (hb_face_t    *face,
    212 					hb_tag_t      table_tag,
    213 					unsigned int  script_index,
    214 					unsigned int  language_index,
    215 					unsigned int  start_offset,
    216 					unsigned int *feature_count /* IN/OUT */,
    217 					hb_tag_t     *feature_tags /* OUT */);
    218 
    219 HB_EXTERN hb_bool_t
    220 hb_ot_layout_language_find_feature (hb_face_t    *face,
    221 				    hb_tag_t      table_tag,
    222 				    unsigned int  script_index,
    223 				    unsigned int  language_index,
    224 				    hb_tag_t      feature_tag,
    225 				    unsigned int *feature_index);
    226 
    227 HB_EXTERN unsigned int
    228 hb_ot_layout_feature_get_lookups (hb_face_t    *face,
    229 				  hb_tag_t      table_tag,
    230 				  unsigned int  feature_index,
    231 				  unsigned int  start_offset,
    232 				  unsigned int *lookup_count /* IN/OUT */,
    233 				  unsigned int *lookup_indexes /* OUT */);
    234 
    235 HB_EXTERN unsigned int
    236 hb_ot_layout_table_get_lookup_count (hb_face_t    *face,
    237 				     hb_tag_t      table_tag);
    238 
    239 HB_EXTERN void
    240 hb_ot_layout_collect_features (hb_face_t      *face,
    241                                hb_tag_t        table_tag,
    242                                const hb_tag_t *scripts,
    243                                const hb_tag_t *languages,
    244                                const hb_tag_t *features,
    245                                hb_set_t       *feature_indexes /* OUT */);
    246 
    247 HB_EXTERN void
    248 hb_ot_layout_collect_lookups (hb_face_t      *face,
    249 			      hb_tag_t        table_tag,
    250 			      const hb_tag_t *scripts,
    251 			      const hb_tag_t *languages,
    252 			      const hb_tag_t *features,
    253 			      hb_set_t       *lookup_indexes /* OUT */);
    254 
    255 HB_EXTERN void
    256 hb_ot_layout_lookup_collect_glyphs (hb_face_t    *face,
    257 				    hb_tag_t      table_tag,
    258 				    unsigned int  lookup_index,
    259 				    hb_set_t     *glyphs_before, /* OUT.  May be NULL */
    260 				    hb_set_t     *glyphs_input,  /* OUT.  May be NULL */
    261 				    hb_set_t     *glyphs_after,  /* OUT.  May be NULL */
    262 				    hb_set_t     *glyphs_output  /* OUT.  May be NULL */);
    263 
    264 #ifdef HB_NOT_IMPLEMENTED
    265 typedef struct
    266 {
    267   const hb_codepoint_t *before,
    268   unsigned int          before_length,
    269   const hb_codepoint_t *input,
    270   unsigned int          input_length,
    271   const hb_codepoint_t *after,
    272   unsigned int          after_length,
    273 } hb_ot_layout_glyph_sequence_t;
    274 
    275 typedef hb_bool_t
    276 (*hb_ot_layout_glyph_sequence_func_t) (hb_font_t    *font,
    277 				       hb_tag_t      table_tag,
    278 				       unsigned int  lookup_index,
    279 				       const hb_ot_layout_glyph_sequence_t *sequence,
    280 				       void         *user_data);
    281 
    282 HB_EXTERN void
    283 Xhb_ot_layout_lookup_enumerate_sequences (hb_face_t    *face,
    284 					 hb_tag_t      table_tag,
    285 					 unsigned int  lookup_index,
    286 					 hb_ot_layout_glyph_sequence_func_t callback,
    287 					 void         *user_data);
    288 #endif
    289 
    290 /* Variations support */
    291 
    292 HB_EXTERN hb_bool_t
    293 hb_ot_layout_table_find_feature_variations (hb_face_t    *face,
    294 					    hb_tag_t      table_tag,
    295 					    const int    *coords,
    296 					    unsigned int  num_coords,
    297 					    unsigned int *variations_index /* out */);
    298 
    299 HB_EXTERN unsigned int
    300 hb_ot_layout_feature_with_variations_get_lookups (hb_face_t    *face,
    301 						  hb_tag_t      table_tag,
    302 						  unsigned int  feature_index,
    303 						  unsigned int  variations_index,
    304 						  unsigned int  start_offset,
    305 						  unsigned int *lookup_count /* IN/OUT */,
    306 						  unsigned int *lookup_indexes /* OUT */);
    307 
    308 
    309 /*
    310  * GSUB
    311  */
    312 
    313 HB_EXTERN hb_bool_t
    314 hb_ot_layout_has_substitution (hb_face_t *face);
    315 
    316 HB_EXTERN hb_bool_t
    317 hb_ot_layout_lookup_would_substitute (hb_face_t            *face,
    318 				      unsigned int          lookup_index,
    319 				      const hb_codepoint_t *glyphs,
    320 				      unsigned int          glyphs_length,
    321 				      hb_bool_t             zero_context);
    322 
    323 HB_EXTERN void
    324 hb_ot_layout_lookup_substitute_closure (hb_face_t    *face,
    325 				        unsigned int  lookup_index,
    326 				        hb_set_t     *glyphs
    327 					/*TODO , hb_bool_t  inclusive */);
    328 
    329 HB_EXTERN void
    330 hb_ot_layout_lookups_substitute_closure (hb_face_t      *face,
    331                                          const hb_set_t *lookups,
    332                                          hb_set_t       *glyphs);
    333 
    334 
    335 #ifdef HB_NOT_IMPLEMENTED
    336 /* Note: You better have GDEF when using this API, or marks won't do much. */
    337 HB_EXTERN hb_bool_t
    338 Xhb_ot_layout_lookup_substitute (hb_font_t            *font,
    339 				unsigned int          lookup_index,
    340 				const hb_ot_layout_glyph_sequence_t *sequence,
    341 				unsigned int          out_size,
    342 				hb_codepoint_t       *glyphs_out,   /* OUT */
    343 				unsigned int         *clusters_out, /* OUT */
    344 				unsigned int         *out_length    /* OUT */);
    345 #endif
    346 
    347 
    348 /*
    349  * GPOS
    350  */
    351 
    352 HB_EXTERN hb_bool_t
    353 hb_ot_layout_has_positioning (hb_face_t *face);
    354 
    355 #ifdef HB_NOT_IMPLEMENTED
    356 /* Note: You better have GDEF when using this API, or marks won't do much. */
    357 HB_EXTERN hb_bool_t
    358 Xhb_ot_layout_lookup_position (hb_font_t            *font,
    359 			      unsigned int          lookup_index,
    360 			      const hb_ot_layout_glyph_sequence_t *sequence,
    361 			      hb_glyph_position_t  *positions /* IN / OUT */);
    362 #endif
    363 
    364 /* Optical 'size' feature info.  Returns true if found.
    365  * https://docs.microsoft.com/en-us/typography/opentype/spec/features_pt#size */
    366 HB_EXTERN hb_bool_t
    367 hb_ot_layout_get_size_params (hb_face_t       *face,
    368 			      unsigned int    *design_size,       /* OUT.  May be NULL */
    369 			      unsigned int    *subfamily_id,      /* OUT.  May be NULL */
    370 			      hb_ot_name_id_t *subfamily_name_id, /* OUT.  May be NULL */
    371 			      unsigned int    *range_start,       /* OUT.  May be NULL */
    372 			      unsigned int    *range_end          /* OUT.  May be NULL */);
    373 
    374 
    375 HB_EXTERN hb_bool_t
    376 hb_ot_layout_feature_get_name_ids (hb_face_t       *face,
    377 				   hb_tag_t         table_tag,
    378 				   unsigned int     feature_index,
    379 				   hb_ot_name_id_t *label_id             /* OUT.  May be NULL */,
    380 				   hb_ot_name_id_t *tooltip_id           /* OUT.  May be NULL */,
    381 				   hb_ot_name_id_t *sample_id            /* OUT.  May be NULL */,
    382 				   unsigned int    *num_named_parameters /* OUT.  May be NULL */,
    383 				   hb_ot_name_id_t *first_param_id       /* OUT.  May be NULL */);
    384 
    385 
    386 HB_EXTERN unsigned int
    387 hb_ot_layout_feature_get_characters (hb_face_t      *face,
    388 				     hb_tag_t        table_tag,
    389 				     unsigned int    feature_index,
    390 				     unsigned int    start_offset,
    391 				     unsigned int   *char_count    /* IN/OUT.  May be NULL */,
    392 				     hb_codepoint_t *characters    /* OUT.     May be NULL */);
    393 
    394 HB_END_DECLS
    395 
    396 #endif /* HB_OT_LAYOUT_H */
    397