lib/ta.h

   1 /* ta.h */
   2
   3 /*
   4  * Copyright (C) 2011-2022 by Werner Lemberg.
   5  *
   6  * This file is part of the ttfautohint library, and may only be used,
   7  * modified, and distributed under the terms given in `COPYING'.  By
   8  * continuing to use, modify, or distribute this file you indicate that you
   9  * have read `COPYING' and understand and accept it fully.
  10  *
  11  * The file `COPYING' mentioned in the previous paragraph is distributed
  12  * with the ttfautohint library.
  13  */
  14
  15
  16 #ifndef TA_H_
  17 #define TA_H_
  18
  19 #include <config.h>
  20
  21 #include <ft2build.h>
  22 #include FT_FREETYPE_H
  23 #include FT_TRUETYPE_TABLES_H
  24 #include FT_TRUETYPE_TAGS_H
  25
  26 #include <ttfautohint.h>
  27 #include <sds.h>
  28 #include <numberset.h>
  29
  30 #include "taloader.h"
  31 #include "taglobal.h"
  32 #include "tadummy.h"
  33 #include "talatin.h"
  34
  35
  36 #define TTFAUTOHINT_GLYPH ".ttfautohint"
  37 #define TTFAUTOHINT_GLYPH_FIRST_BYTE "\x0C" /* first byte is string length */
  38 #define TTFAUTOHINT_GLYPH_LEN 13
  39
  40
  41 /* these macros convert 16bit and 32bit numbers into single bytes */
  42 /* using the byte order needed within SFNT files */
  43
  44 #define HIGH(x) (FT_Byte)(((x) & 0xFF00) >> 8)
  45 #define LOW(x) ((x) & 0x00FF)
  46
  47 #define BYTE1(x) (FT_Byte)(((FT_ULong)(x) & 0xFF000000UL) >> 24);
  48 #define BYTE2(x) (FT_Byte)(((FT_ULong)(x) & 0x00FF0000UL) >> 16);
  49 #define BYTE3(x) (FT_Byte)(((FT_ULong)(x) & 0x0000FF00UL) >> 8);
  50 #define BYTE4(x) ((FT_ULong)(x) & 0x000000FFUL);
  51
  52 /* utility macros to get data from a pointer (with auto-increment) */
  53
  54 #define NEXT_USHORT(buffer) \
  55           ((FT_UShort)(buffer += 2, (FT_UShort)buffer[-2] << 8 \
  56                                     | (FT_UShort)buffer[-1]))
  57 #define NEXT_ULONG(buffer) \
  58           ((FT_ULong)(buffer += 4, (FT_ULong)buffer[-4] << 24 \
  59                                    | (FT_ULong)buffer[-3] << 16 \
  60                                    | (FT_ULong)buffer[-2] << 8 \
  61                                    | (FT_ULong)buffer[-1]))
  62
  63
  64 /* an SFNT tag for our information table */
  65 #define TTAG_TTFA FT_MAKE_TAG('T', 'T', 'F', 'A')
  66
  67 /* the length of a dummy `DSIG' table */
  68 #define DSIG_LEN 8
  69
  70 /* the length of our `gasp' table */
  71 #define GASP_LEN 8
  72
  73 /* an empty slot in the table info array */
  74 #define MISSING ~0U
  75
  76 /* the offset to the loca table format in the `head' table */
  77 #define LOCA_FORMAT_OFFSET 51
  78
  79 /* various offsets within the `maxp' table */
  80 #define MAXP_NUM_GLYPHS 4
  81 #define MAXP_MAX_COMPOSITE_POINTS 10
  82 #define MAXP_MAX_COMPOSITE_CONTOURS 12
  83 #define MAXP_MAX_ZONES_OFFSET 14
  84 #define MAXP_MAX_TWILIGHT_POINTS_OFFSET 16
  85 #define MAXP_MAX_STORAGE_OFFSET 18
  86 #define MAXP_MAX_FUNCTION_DEFS_OFFSET 20
  87 #define MAXP_MAX_INSTRUCTION_DEFS_OFFSET 22
  88 #define MAXP_MAX_STACK_ELEMENTS_OFFSET 24
  89 #define MAXP_MAX_INSTRUCTIONS_OFFSET 26
  90 #define MAXP_MAX_COMPONENTS_OFFSET 28
  91
  92 #define MAXP_LEN 32
  93
  94 /* the offset of the type flags field in the `OS/2' table */
  95 #define OS2_FSTYPE_OFFSET 8
  96
  97
  98 /* flags in composite glyph records */
  99 #define ARGS_ARE_WORDS 0x0001
 100 #define ARGS_ARE_XY_VALUES 0x0002
 101 #define WE_HAVE_A_SCALE 0x0008
 102 #define MORE_COMPONENTS 0x0020
 103 #define WE_HAVE_AN_XY_SCALE 0x0040
 104 #define WE_HAVE_A_2X2 0x0080
 105 #define WE_HAVE_INSTR 0x0100
 106
 107 /* flags in simple glyph records */
 108 #define ON_CURVE 0x01
 109 #define X_SHORT_VECTOR 0x02
 110 #define Y_SHORT_VECTOR 0x04
 111 #define REPEAT 0x08
 112 #define SAME_X 0x10
 113 #define SAME_Y 0x20
 114
 115
 116 /* a single glyph */
 117 typedef struct GLYPH_
 118 {
 119   FT_ULong len1; /* number of bytes before instruction related data */
 120   FT_ULong len2; /* number of bytes after instruction related data; */
 121                  /* if zero, this indicates a composite glyph */
 122   FT_Byte* buf; /* extracted glyph data (without instruction related data) */
 123   FT_ULong flags_offset; /* offset to last flag in a composite glyph */
 124
 125   FT_Byte ins_extra_len; /* number of extra instructions */
 126   FT_Byte* ins_extra_buf; /* extra instructions data */
 127   FT_ULong ins_len; /* number of new instructions */
 128   FT_Byte* ins_buf; /* new instruction data */
 129
 130   FT_Short num_contours; /* >= 0 for simple glyphs */
 131   FT_UShort num_points; /* number of points in a simple glyph */
 132
 133   FT_UShort num_components;
 134   FT_UShort* components; /* the subglyph indices of a composite glyph */
 135
 136   FT_UShort num_pointsums;
 137   FT_UShort* pointsums; /* the pointsums of all composite elements */
 138                         /* (after walking recursively over all subglyphs) */
 139
 140   FT_UShort num_composite_contours; /* after recursion */
 141 } GLYPH;
 142
 143 /* a representation of the data in the `glyf' table */
 144 typedef struct glyf_Data_
 145 {
 146   FT_UShort num_glyphs;
 147   GLYPH* glyphs;
 148
 149   /* this field gives the `master' globals for a `glyf' table; */
 150   /* see function `TA_sfnt_handle_coverage' */
 151   TA_FaceGlobals master_globals;
 152   /* for coverage bookkeeping */
 153   FT_Bool adjusted;
 154
 155   /* if a `glyf' table gets used in more than one subfont, */
 156   /* so do `cvt', `fpgm', and `prep' tables: */
 157   /* these four tables are always handled in parallel */
 158   FT_ULong cvt_idx;
 159   FT_ULong fpgm_idx;
 160   FT_ULong prep_idx;
 161
 162   /* styles present in a font get a running number; */
 163   /* unavailable styles get value 0xFFFF */
 164   FT_UInt style_ids[TA_STYLE_MAX];
 165   FT_UInt num_used_styles;
 166
 167   /* we have separate CVT data for each style */
 168   FT_UInt cvt_offsets[TA_STYLE_MAX];
 169   FT_UInt cvt_horz_width_sizes[TA_STYLE_MAX];
 170   FT_UInt cvt_vert_width_sizes[TA_STYLE_MAX];
 171   FT_UInt cvt_blue_zone_sizes[TA_STYLE_MAX];
 172   FT_UInt cvt_blue_adjustment_offsets[TA_STYLE_MAX];
 173 } glyf_Data;
 174
 175 /* an SFNT table */
 176 typedef struct SFNT_Table_
 177 {
 178   FT_ULong tag;
 179   FT_ULong len;
 180   FT_Byte* buf; /* the table data */
 181   FT_ULong offset; /* from beginning of file */
 182   FT_ULong checksum;
 183   void* data; /* used e.g. for `glyf' table data */
 184   FT_Bool processed;
 185 } SFNT_Table;
 186
 187 /* we use indices into the SFNT table array to */
 188 /* represent table info records of the TTF header */
 189 typedef FT_ULong SFNT_Table_Info;
 190
 191 /* this structure is used to model a TTF or a subfont within a TTC */
 192 typedef struct SFNT_
 193 {
 194   FT_Face face;
 195
 196   SFNT_Table_Info* table_infos;
 197   FT_ULong num_table_infos;
 198
 199   /* various SFNT table indices */
 200   FT_ULong glyf_idx;
 201   FT_ULong loca_idx;
 202   FT_ULong head_idx;
 203   FT_ULong hmtx_idx;
 204   FT_ULong maxp_idx;
 205   FT_ULong name_idx;
 206   FT_ULong post_idx;
 207   FT_ULong OS2_idx;
 208   FT_ULong GPOS_idx;
 209
 210   /* values necessary to update the `maxp' table */
 211   FT_UShort max_composite_points;
 212   FT_UShort max_composite_contours;
 213   FT_UShort max_storage;
 214   FT_UShort max_stack_elements;
 215   FT_UShort max_twilight_points;
 216   FT_UShort max_instructions;
 217   FT_UShort max_components;
 218 } SFNT;
 219
 220 typedef struct Control_ Control;
 221
 222 /* our font object; the `FONT' typedef is in `taloader.h' */
 223 struct FONT_
 224 {
 225   FT_Library lib;
 226
 227   FT_Byte* in_buf;
 228   size_t in_len;
 229
 230   FT_Byte* out_buf;
 231   size_t out_len;
 232
 233   char* control_buf;
 234   size_t control_len;
 235
 236   FT_Byte* reference_buf;
 237   size_t reference_len;
 238
 239   FT_Face reference;
 240   FT_Long reference_index;
 241   const char* reference_name;
 242
 243   SFNT* sfnts;
 244   FT_Long num_sfnts;
 245
 246   SFNT_Table* tables;
 247   FT_ULong num_tables;
 248
 249   FT_Bool have_DSIG;
 250
 251   /* we have a single `gasp' table for all subfonts */
 252   FT_ULong gasp_idx;
 253
 254   /* the control instructions */
 255   Control* control;
 256
 257   /* two generic pointers into the control instructions tree */
 258   void* control_data_head;
 259   void* control_data_cur;
 260
 261   /* two fields for handling one-point segment directions */
 262   /* of the current glyph */
 263   void* control_segment_dirs_head;
 264   void* control_segment_dirs_cur;
 265
 266   TA_LoaderRec loader[1]; /* the interface to the autohinter */
 267
 268   /* configuration options */
 269   TA_Progress_Func progress;
 270   void* progress_data;
 271   TA_Info_Func info;
 272   TA_Info_Post_Func info_post;
 273   void* info_data;
 274   TA_Alloc_Func allocate;
 275   TA_Free_Func deallocate;
 276   FT_UInt hinting_range_min;
 277   FT_UInt hinting_range_max;
 278   FT_UInt hinting_limit;
 279   FT_UInt increase_x_height;
 280   number_range* x_height_snapping_exceptions;
 281   FT_UInt fallback_stem_width;
 282   FT_Int gray_stem_width_mode;
 283   FT_Int gdi_cleartype_stem_width_mode;
 284   FT_Int dw_cleartype_stem_width_mode;
 285   FT_Bool windows_compatibility;
 286   FT_Bool adjust_subglyphs;
 287   FT_Bool hint_composites;
 288   FT_Bool ignore_restrictions;
 289   TA_Style fallback_style;
 290   FT_Bool fallback_scaling;
 291   TA_Script default_script;
 292   FT_Bool symbol;
 293   FT_Bool dehint;
 294   FT_Bool debug;
 295   FT_Bool TTFA_info;
 296   unsigned long long epoch;
 297 };
 298
 299
 300 #include "tatables.h"
 301 #include "tabytecode.h"
 302 #include "tacontrol.h"
 303
 304
 305 /* in file `tascript.c' */
 306 extern const char* script_names[];
 307 extern size_t script_names_size;
 308
 309
 310 const char*
 311 TA_get_error_message(FT_Error error);
 312
 313 char*
 314 TA_font_dump_parameters(FONT* font,
 315                         FT_Bool format);
 316
 317 void
 318 TA_get_current_time(FONT* font,
 319                     FT_ULong* high,
 320                     FT_ULong* low);
 321
 322 FT_Byte*
 323 TA_build_push(FT_Byte* bufp,
 324               FT_UInt* args,
 325               FT_UInt num_args,
 326               FT_Bool need_words,
 327               FT_Bool optimize);
 328
 329 FT_Error
 330 TA_font_init(FONT* font);
 331 void
 332 TA_font_unload(FONT* font,
 333                const char* in_buf,
 334                char** out_bufp,
 335                const char* control_buf,
 336                const char* reference_buf);
 337
 338 FT_Error
 339 TA_font_file_read(FILE* file,
 340                   FT_Byte** buffer,
 341                   size_t* length);
 342 FT_Error
 343 TA_font_file_write(FONT* font,
 344                    FILE* out_file);
 345 FT_Error
 346 TA_control_file_read(FONT* font,
 347                      FILE* control_file);
 348
 349 FT_Error
 350 TA_sfnt_compute_composite_pointsums(SFNT* sfnt,
 351                                     FONT* font);
 352
 353 FT_Error
 354 TA_sfnt_build_glyph_instructions(SFNT* sfnt,
 355                                  FONT* font,
 356                                  FT_Long idx);
 357
 358 FT_Error
 359 TA_sfnt_split_into_SFNT_tables(SFNT* sfnt,
 360                                FONT* font);
 361
 362 FT_Error
 363 TA_sfnt_build_cvt_table(SFNT* sfnt,
 364                         FONT* font);
 365
 366 FT_Error
 367 TA_table_build_TTFA(FT_Byte** TTFA,
 368                     FT_ULong* TTFA_len,
 369                     FONT* font);
 370
 371 FT_Error
 372 TA_table_build_DSIG(FT_Byte** DSIG);
 373
 374 FT_Error
 375 TA_sfnt_build_fpgm_table(SFNT* sfnt,
 376                          FONT* font);
 377
 378 FT_Error
 379 TA_sfnt_build_gasp_table(SFNT* sfnt,
 380                          FONT* font);
 381
 382 FT_Error
 383 TA_sfnt_split_glyf_table(SFNT* sfnt,
 384                          FONT* font);
 385 FT_Error
 386 TA_sfnt_build_glyf_table(SFNT* sfnt,
 387                          FONT* font);
 388 FT_Error
 389 TA_sfnt_create_glyf_data(SFNT* sfnt,
 390                          FONT* font);
 391 FT_Error
 392 TA_sfnt_handle_coverage(SFNT* sfnt,
 393                         FONT* font);
 394 void
 395 TA_sfnt_adjust_coverage(SFNT* sfnt,
 396                         FONT* font);
 397 #if 0
 398 void
 399 TA_sfnt_copy_master_coverage(SFNT* sfnt,
 400                              FONT* font);
 401 #endif
 402
 403 FT_Error
 404 TA_sfnt_update_GPOS_table(SFNT* sfnt,
 405                           FONT* font);
 406
 407 FT_Error
 408 TA_sfnt_update_hmtx_table(SFNT* sfnt,
 409                           FONT* font);
 410
 411 FT_Error
 412 TA_sfnt_build_loca_table(SFNT* sfnt,
 413                          FONT* font);
 414
 415 FT_Error
 416 TA_sfnt_update_maxp_table(SFNT* sfnt,
 417                           FONT* font);
 418
 419 FT_Error
 420 TA_sfnt_update_post_table(SFNT* sfnt,
 421                           FONT* font);
 422
 423 FT_Error
 424 TA_sfnt_update_name_table(SFNT* sfnt,
 425                           FONT* font);
 426
 427 FT_Error
 428 TA_sfnt_build_prep_table(SFNT* sfnt,
 429                          FONT* font);
 430
 431 FT_Error
 432 TA_sfnt_build_TTF_header(SFNT* sfnt,
 433                          FONT* font,
 434                          FT_Byte** header_buf,
 435                          FT_ULong* header_len,
 436                          FT_Int do_complete);
 437 FT_Error
 438 TA_font_build_TTF(FONT* font);
 439
 440 FT_Error
 441 TA_font_build_TTC(FONT* font);
 442
 443 #endif /* TA_H_ */
 444
 445 /* end of ta.h */