lib/ta.h

   1 /* ta.h */
   2
   3 /*
   4  * Copyright (C) 2011-2015 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 /* these macros convert 16bit and 32bit numbers into single bytes */
  41 /* using the byte order needed within SFNT files */
  42
  43 #define HIGH(x) (FT_Byte)(((x) & 0xFF00) >> 8)
  44 #define LOW(x) ((x) & 0x00FF)
  45
  46 #define BYTE1(x) (FT_Byte)(((x) & 0xFF000000UL) >> 24);
  47 #define BYTE2(x) (FT_Byte)(((x) & 0x00FF0000UL) >> 16);
  48 #define BYTE3(x) (FT_Byte)(((x) & 0x0000FF00UL) >> 8);
  49 #define BYTE4(x) ((x) & 0x000000FFUL);
  50
  51
  52 /* an SFNT tag for our information table */
  53 #define TTAG_TTFA FT_MAKE_TAG('T', 'T', 'F', 'A')
  54
  55 /* the length of a dummy `DSIG' table */
  56 #define DSIG_LEN 8
  57
  58 /* the length of our `gasp' table */
  59 #define GASP_LEN 8
  60
  61 /* an empty slot in the table info array */
  62 #define MISSING (FT_ULong)~0
  63
  64 /* the offset to the loca table format in the `head' table */
  65 #define LOCA_FORMAT_OFFSET 51
  66
  67 /* various offsets within the `maxp' table */
  68 #define MAXP_NUM_GLYPHS 4
  69 #define MAXP_MAX_COMPOSITE_POINTS 10
  70 #define MAXP_MAX_COMPOSITE_CONTOURS 12
  71 #define MAXP_MAX_ZONES_OFFSET 14
  72 #define MAXP_MAX_TWILIGHT_POINTS_OFFSET 16
  73 #define MAXP_MAX_STORAGE_OFFSET 18
  74 #define MAXP_MAX_FUNCTION_DEFS_OFFSET 20
  75 #define MAXP_MAX_INSTRUCTION_DEFS_OFFSET 22
  76 #define MAXP_MAX_STACK_ELEMENTS_OFFSET 24
  77 #define MAXP_MAX_INSTRUCTIONS_OFFSET 26
  78 #define MAXP_MAX_COMPONENTS_OFFSET 28
  79
  80 #define MAXP_LEN 32
  81
  82 /* the offset of the type flags field in the `OS/2' table */
  83 #define OS2_FSTYPE_OFFSET 8
  84
  85
  86 /* flags in composite glyph records */
  87 #define ARGS_ARE_WORDS 0x0001
  88 #define ARGS_ARE_XY_VALUES 0x0002
  89 #define WE_HAVE_A_SCALE 0x0008
  90 #define MORE_COMPONENTS 0x0020
  91 #define WE_HAVE_AN_XY_SCALE 0x0040
  92 #define WE_HAVE_A_2X2 0x0080
  93 #define WE_HAVE_INSTR 0x0100
  94
  95 /* flags in simple glyph records */
  96 #define ON_CURVE 0x01
  97 #define X_SHORT_VECTOR 0x02
  98 #define Y_SHORT_VECTOR 0x04
  99 #define REPEAT 0x08
 100 #define SAME_X 0x10
 101 #define SAME_Y 0x20
 102
 103
 104 /* a single glyph */
 105 typedef struct GLYPH_
 106 {
 107   FT_ULong len1; /* number of bytes before instruction related data */
 108   FT_ULong len2; /* number of bytes after instruction related data; */
 109                  /* if zero, this indicates a composite glyph */
 110   FT_Byte* buf; /* extracted glyph data (without instruction related data) */
 111   FT_ULong flags_offset; /* offset to last flag in a composite glyph */
 112
 113   FT_Byte ins_extra_len; /* number of extra instructions; */
 114                          /* see `ins_extra_buf' in `tabytecode.h' */
 115   FT_ULong ins_len; /* number of new instructions */
 116   FT_Byte* ins_buf; /* new instruction data */
 117
 118   FT_Short num_contours; /* >= 0 for simple glyphs */
 119   FT_UShort num_points; /* number of points in a simple glyph */
 120
 121   FT_UShort num_components;
 122   FT_UShort* components; /* the subglyph indices of a composite glyph */
 123
 124   FT_UShort num_pointsums;
 125   FT_UShort* pointsums; /* the pointsums of all composite elements */
 126                         /* (after walking recursively over all subglyphs) */
 127
 128   FT_UShort num_composite_contours; /* after recursion */
 129 } GLYPH;
 130
 131 /* a representation of the data in the `glyf' table */
 132 typedef struct glyf_Data_
 133 {
 134   FT_UShort num_glyphs;
 135   GLYPH* glyphs;
 136
 137   /* this field gives the `master' globals for a `glyf' table; */
 138   /* see function `TA_sfnt_handle_coverage' */
 139   TA_FaceGlobals master_globals;
 140   /* for coverage bookkeeping */
 141   FT_Bool adjusted;
 142
 143   /* if a `glyf' table gets used in more than one subfont, */
 144   /* so do `cvt', `fpgm', and `prep' tables: */
 145   /* these four tables are always handled in parallel */
 146   FT_ULong cvt_idx;
 147   FT_ULong fpgm_idx;
 148   FT_ULong prep_idx;
 149
 150   /* styles present in a font get a running number */
 151   FT_UInt style_ids[TA_STYLE_MAX];
 152   FT_UInt num_used_styles;
 153
 154   /* we have separate CVT data for each style */
 155   FT_UInt cvt_offsets[TA_STYLE_MAX];
 156   FT_UInt cvt_horz_width_sizes[TA_STYLE_MAX];
 157   FT_UInt cvt_vert_width_sizes[TA_STYLE_MAX];
 158   FT_UInt cvt_blue_zone_sizes[TA_STYLE_MAX];
 159   FT_UInt cvt_blue_adjustment_offsets[TA_STYLE_MAX];
 160 } glyf_Data;
 161
 162 /* an SFNT table */
 163 typedef struct SFNT_Table_
 164 {
 165   FT_ULong tag;
 166   FT_ULong len;
 167   FT_Byte* buf; /* the table data */
 168   FT_ULong offset; /* from beginning of file */
 169   FT_ULong checksum;
 170   void* data; /* used e.g. for `glyf' table data */
 171   FT_Bool processed;
 172 } SFNT_Table;
 173
 174 /* we use indices into the SFNT table array to */
 175 /* represent table info records of the TTF header */
 176 typedef FT_ULong SFNT_Table_Info;
 177
 178 /* this structure is used to model a TTF or a subfont within a TTC */
 179 typedef struct SFNT_
 180 {
 181   FT_Face face;
 182
 183   SFNT_Table_Info* table_infos;
 184   FT_ULong num_table_infos;
 185
 186   /* various SFNT table indices */
 187   FT_ULong glyf_idx;
 188   FT_ULong loca_idx;
 189   FT_ULong head_idx;
 190   FT_ULong hmtx_idx;
 191   FT_ULong maxp_idx;
 192   FT_ULong name_idx;
 193   FT_ULong post_idx;
 194   FT_ULong OS2_idx;
 195   FT_ULong GPOS_idx;
 196
 197   /* values necessary to update the `maxp' table */
 198   FT_UShort max_composite_points;
 199   FT_UShort max_composite_contours;
 200   FT_UShort max_storage;
 201   FT_UShort max_stack_elements;
 202   FT_UShort max_twilight_points;
 203   FT_UShort max_instructions;
 204   FT_UShort max_components;
 205 } SFNT;
 206
 207 typedef struct Control_ Control;
 208
 209 /* our font object; the `FONT' typedef is in `taloader.h' */
 210 struct FONT_
 211 {
 212   FT_Library lib;
 213
 214   FT_Byte* in_buf;
 215   size_t in_len;
 216
 217   FT_Byte* out_buf;
 218   size_t out_len;
 219
 220   char* control_buf;
 221   size_t control_len;
 222
 223   SFNT* sfnts;
 224   FT_Long num_sfnts;
 225
 226   SFNT_Table* tables;
 227   FT_ULong num_tables;
 228
 229   FT_Bool have_DSIG;
 230
 231   /* we have a single `gasp' table for all subfonts */
 232   FT_ULong gasp_idx;
 233
 234   /* the control instructions */
 235   Control* control;
 236
 237   /* two generic pointers into the control instructions tree */
 238   void* control_data_head;
 239   void* control_data_cur;
 240
 241   /* two fields for handling one-point segment directions */
 242   /* of the current glyph */
 243   void* control_segment_dirs_head;
 244   void* control_segment_dirs_cur;
 245
 246   TA_LoaderRec loader[1]; /* the interface to the autohinter */
 247
 248   /* configuration options */
 249   TA_Progress_Func progress;
 250   void* progress_data;
 251   TA_Info_Func info;
 252   TA_Info_Post_Func info_post;
 253   void* info_data;
 254   FT_UInt hinting_range_min;
 255   FT_UInt hinting_range_max;
 256   FT_UInt hinting_limit;
 257   FT_UInt increase_x_height;
 258   number_range* x_height_snapping_exceptions;
 259   FT_UInt fallback_stem_width;
 260   FT_Bool gray_strong_stem_width;
 261   FT_Bool gdi_cleartype_strong_stem_width;
 262   FT_Bool dw_cleartype_strong_stem_width;
 263   FT_Bool windows_compatibility;
 264   FT_Bool adjust_subglyphs;
 265   FT_Bool hint_composites;
 266   FT_Bool ignore_restrictions;
 267   TA_Style fallback_style;
 268   TA_Script default_script;
 269   FT_Bool symbol;
 270   FT_Bool dehint;
 271   FT_Bool debug;
 272   FT_Bool TTFA_info;
 273 };
 274
 275
 276 #include "tatables.h"
 277 #include "tabytecode.h"
 278 #include "tacontrol.h"
 279
 280
 281 /* in file `tascript.c' */
 282 extern const char* script_names[];
 283
 284
 285 const char*
 286 TA_get_error_message(FT_Error error);
 287
 288 char*
 289 TA_font_dump_parameters(FONT* font,
 290                         FT_Bool format);
 291
 292 void
 293 TA_get_current_time(FT_ULong* high,
 294                     FT_ULong* low);
 295
 296 FT_Byte*
 297 TA_build_push(FT_Byte* bufp,
 298               FT_UInt* args,
 299               FT_UInt num_args,
 300               FT_Bool need_words,
 301               FT_Bool optimize);
 302
 303 FT_Error
 304 TA_font_init(FONT* font);
 305 void
 306 TA_font_unload(FONT* font,
 307                const char* in_buf,
 308                char** out_bufp,
 309                const char* control_buf);
 310
 311 FT_Error
 312 TA_font_file_read(FONT* font,
 313                   FILE* in_file);
 314 FT_Error
 315 TA_font_file_write(FONT* font,
 316                    FILE* out_file);
 317 FT_Error
 318 TA_control_file_read(FONT* font,
 319                      FILE* control_file);
 320
 321 FT_Error
 322 TA_sfnt_build_glyph_instructions(SFNT* sfnt,
 323                                  FONT* font,
 324                                  FT_Long idx);
 325
 326 FT_Error
 327 TA_sfnt_split_into_SFNT_tables(SFNT* sfnt,
 328                                FONT* font);
 329
 330 FT_Error
 331 TA_sfnt_build_cvt_table(SFNT* sfnt,
 332                         FONT* font);
 333
 334 FT_Error
 335 TA_table_build_TTFA(FT_Byte** TTFA,
 336                     FT_ULong* TTFA_len,
 337                     FONT* font);
 338
 339 FT_Error
 340 TA_table_build_DSIG(FT_Byte** DSIG);
 341
 342 FT_Error
 343 TA_sfnt_build_fpgm_table(SFNT* sfnt,
 344                          FONT* font);
 345
 346 FT_Error
 347 TA_sfnt_build_gasp_table(SFNT* sfnt,
 348                          FONT* font);
 349
 350 FT_Error
 351 TA_sfnt_split_glyf_table(SFNT* sfnt,
 352                          FONT* font);
 353 FT_Error
 354 TA_sfnt_build_glyf_table(SFNT* sfnt,
 355                          FONT* font);
 356 FT_Error
 357 TA_sfnt_create_glyf_data(SFNT* sfnt,
 358                          FONT* font);
 359 FT_Error
 360 TA_sfnt_handle_coverage(SFNT* sfnt,
 361                         FONT* font);
 362 void
 363 TA_sfnt_adjust_coverage(SFNT* sfnt,
 364                         FONT* font);
 365 #if 0
 366 void
 367 TA_sfnt_copy_master_coverage(SFNT* sfnt,
 368                              FONT* font);
 369 #endif
 370
 371 FT_Error
 372 TA_sfnt_update_GPOS_table(SFNT* sfnt,
 373                           FONT* font);
 374
 375 FT_Error
 376 TA_sfnt_update_hmtx_table(SFNT* sfnt,
 377                           FONT* font);
 378
 379 FT_Error
 380 TA_sfnt_build_loca_table(SFNT* sfnt,
 381                          FONT* font);
 382
 383 FT_Error
 384 TA_sfnt_update_maxp_table(SFNT* sfnt,
 385                           FONT* font);
 386
 387 FT_Error
 388 TA_sfnt_update_post_table(SFNT* sfnt,
 389                           FONT* font);
 390
 391 FT_Error
 392 TA_sfnt_update_name_table(SFNT* sfnt,
 393                           FONT* font);
 394
 395 FT_Error
 396 TA_sfnt_build_prep_table(SFNT* sfnt,
 397                          FONT* font);
 398
 399 FT_Error
 400 TA_sfnt_build_TTF_header(SFNT* sfnt,
 401                          FONT* font,
 402                          FT_Byte** header_buf,
 403                          FT_ULong* header_len,
 404                          FT_Int do_complete);
 405 FT_Error
 406 TA_font_build_TTF(FONT* font);
 407
 408 FT_Error
 409 TA_font_build_TTC(FONT* font);
 410
 411 #endif /* __TA_H__ */
 412
 413 /* end of ta.h */