lib/ta.h

   1 /* ta.h */
   2
   3 /*
   4  * Copyright (C) 2011-2014 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 "taloader.h"
  27 #include "taglobal.h"
  28 #include "tadummy.h"
  29 #include "talatin.h"
  30
  31 #include <ttfautohint.h>
  32 #include <numberset.h>
  33
  34
  35 #define TTFAUTOHINT_GLYPH ".ttfautohint"
  36 #define TTFAUTOHINT_GLYPH_FIRST_BYTE "\x0C" /* first byte is string length */
  37 #define TTFAUTOHINT_GLYPH_LEN 13
  38
  39 /* these macros convert 16bit and 32bit numbers into single bytes */
  40 /* using the byte order needed within SFNT files */
  41
  42 #define HIGH(x) (FT_Byte)(((x) & 0xFF00) >> 8)
  43 #define LOW(x) ((x) & 0x00FF)
  44
  45 #define BYTE1(x) (FT_Byte)(((x) & 0xFF000000UL) >> 24);
  46 #define BYTE2(x) (FT_Byte)(((x) & 0x00FF0000UL) >> 16);
  47 #define BYTE3(x) (FT_Byte)(((x) & 0x0000FF00UL) >> 8);
  48 #define BYTE4(x) ((x) & 0x000000FFUL);
  49
  50
  51 /* the length of a dummy `DSIG' table */
  52 #define DSIG_LEN 8
  53
  54 /* the length of our `gasp' table */
  55 #define GASP_LEN 8
  56
  57 /* an empty slot in the table info array */
  58 #define MISSING (FT_ULong)~0
  59
  60 /* the offset to the loca table format in the `head' table */
  61 #define LOCA_FORMAT_OFFSET 51
  62
  63 /* various offsets within the `maxp' table */
  64 #define MAXP_NUM_GLYPHS 4
  65 #define MAXP_MAX_COMPOSITE_POINTS 10
  66 #define MAXP_MAX_COMPOSITE_CONTOURS 12
  67 #define MAXP_MAX_ZONES_OFFSET 14
  68 #define MAXP_MAX_TWILIGHT_POINTS_OFFSET 16
  69 #define MAXP_MAX_STORAGE_OFFSET 18
  70 #define MAXP_MAX_FUNCTION_DEFS_OFFSET 20
  71 #define MAXP_MAX_INSTRUCTION_DEFS_OFFSET 22
  72 #define MAXP_MAX_STACK_ELEMENTS_OFFSET 24
  73 #define MAXP_MAX_INSTRUCTIONS_OFFSET 26
  74 #define MAXP_MAX_COMPONENTS_OFFSET 28
  75
  76 #define MAXP_LEN 32
  77
  78 /* the offset of the type flags field in the `OS/2' table */
  79 #define OS2_FSTYPE_OFFSET 8
  80
  81
  82 /* flags in composite glyph records */
  83 #define ARGS_ARE_WORDS 0x0001
  84 #define ARGS_ARE_XY_VALUES 0x0002
  85 #define WE_HAVE_A_SCALE 0x0008
  86 #define MORE_COMPONENTS 0x0020
  87 #define WE_HAVE_AN_XY_SCALE 0x0040
  88 #define WE_HAVE_A_2X2 0x0080
  89 #define WE_HAVE_INSTR 0x0100
  90
  91 /* flags in simple glyph records */
  92 #define ON_CURVE 0x01
  93 #define X_SHORT_VECTOR 0x02
  94 #define Y_SHORT_VECTOR 0x04
  95 #define REPEAT 0x08
  96 #define SAME_X 0x10
  97 #define SAME_Y 0x20
  98
  99
 100 /* a single glyph */
 101 typedef struct GLYPH_
 102 {
 103   FT_ULong len1; /* number of bytes before instruction related data */
 104   FT_ULong len2; /* number of bytes after instruction related data; */
 105                  /* if zero, this indicates a composite glyph */
 106   FT_Byte* buf; /* extracted glyph data (without instruction related data) */
 107   FT_ULong flags_offset; /* offset to last flag in a composite glyph */
 108
 109   FT_ULong ins_len; /* number of new instructions */
 110   FT_Byte* ins_buf; /* new instruction data */
 111
 112   FT_Short num_contours; /* >= 0 for simple glyphs */
 113   FT_UShort num_points; /* number of points in a simple glyph */
 114
 115   FT_UShort num_components;
 116   FT_UShort* components; /* the subglyph indices of a composite glyph */
 117
 118   FT_UShort num_pointsums;
 119   FT_UShort* pointsums; /* the pointsums of all composite elements */
 120                         /* (after walking recursively over all subglyphs) */
 121
 122   FT_UShort num_composite_contours; /* after recursion */
 123 } GLYPH;
 124
 125 /* a representation of the data in the `glyf' table */
 126 typedef struct glyf_Data_
 127 {
 128   FT_UShort num_glyphs;
 129   GLYPH* glyphs;
 130
 131   /* this field gives the `master' globals for a `glyf' table; */
 132   /* see function `TA_sfnt_handle_coverage' */
 133   TA_FaceGlobals master_globals;
 134   /* for coverage bookkeeping */
 135   FT_Bool adjusted;
 136
 137   /* if a `glyf' table gets used in more than one subfont, */
 138   /* so do `cvt', `fpgm', and `prep' tables: */
 139   /* these four tables are always handled in parallel */
 140   FT_ULong cvt_idx;
 141   FT_ULong fpgm_idx;
 142   FT_ULong prep_idx;
 143
 144   /* styles present in a font get a running number */
 145   FT_UInt style_ids[TA_STYLE_MAX];
 146   FT_UInt num_used_styles;
 147
 148   /* we have separate CVT data for each style */
 149   FT_UInt cvt_offsets[TA_STYLE_MAX];
 150   FT_UInt cvt_horz_width_sizes[TA_STYLE_MAX];
 151   FT_UInt cvt_vert_width_sizes[TA_STYLE_MAX];
 152   FT_UInt cvt_blue_zone_sizes[TA_STYLE_MAX];
 153   FT_UInt cvt_blue_adjustment_offsets[TA_STYLE_MAX];
 154 } glyf_Data;
 155
 156 /* an SFNT table */
 157 typedef struct SFNT_Table_
 158 {
 159   FT_ULong tag;
 160   FT_ULong len;
 161   FT_Byte* buf; /* the table data */
 162   FT_ULong offset; /* from beginning of file */
 163   FT_ULong checksum;
 164   void* data; /* used e.g. for `glyf' table data */
 165   FT_Bool processed;
 166 } SFNT_Table;
 167
 168 /* we use indices into the SFNT table array to */
 169 /* represent table info records of the TTF header */
 170 typedef FT_ULong SFNT_Table_Info;
 171
 172 /* this structure is used to model a TTF or a subfont within a TTC */
 173 typedef struct SFNT_
 174 {
 175   FT_Face face;
 176
 177   SFNT_Table_Info* table_infos;
 178   FT_ULong num_table_infos;
 179
 180   /* various SFNT table indices */
 181   FT_ULong glyf_idx;
 182   FT_ULong loca_idx;
 183   FT_ULong head_idx;
 184   FT_ULong hmtx_idx;
 185   FT_ULong maxp_idx;
 186   FT_ULong name_idx;
 187   FT_ULong post_idx;
 188   FT_ULong OS2_idx;
 189   FT_ULong GPOS_idx;
 190
 191   /* values necessary to update the `maxp' table */
 192   FT_UShort max_composite_points;
 193   FT_UShort max_composite_contours;
 194   FT_UShort max_storage;
 195   FT_UShort max_stack_elements;
 196   FT_UShort max_twilight_points;
 197   FT_UShort max_instructions;
 198   FT_UShort max_components;
 199 } SFNT;
 200
 201 /* our font object */
 202 struct FONT_
 203 {
 204   FT_Library lib;
 205
 206   FT_Byte* in_buf;
 207   size_t in_len;
 208
 209   FT_Byte* out_buf;
 210   size_t out_len;
 211
 212   SFNT* sfnts;
 213   FT_Long num_sfnts;
 214
 215   SFNT_Table* tables;
 216   FT_ULong num_tables;
 217
 218   FT_Bool have_DSIG;
 219
 220   /* we have a single `gasp' table for all subfonts */
 221   FT_ULong gasp_idx;
 222
 223   TA_LoaderRec loader[1]; /* the interface to the autohinter */
 224
 225   /* configuration options */
 226   TA_Progress_Func progress;
 227   void* progress_data;
 228   TA_Info_Func info;
 229   void* info_data;
 230   FT_UInt hinting_range_min;
 231   FT_UInt hinting_range_max;
 232   FT_UInt hinting_limit;
 233   FT_UInt increase_x_height;
 234   number_range* x_height_snapping_exceptions;
 235   FT_UInt fallback_stem_width;
 236   FT_Bool gray_strong_stem_width;
 237   FT_Bool gdi_cleartype_strong_stem_width;
 238   FT_Bool dw_cleartype_strong_stem_width;
 239   FT_Bool windows_compatibility;
 240   FT_Bool adjust_subglyphs;
 241   FT_Bool hint_composites;
 242   FT_Bool ignore_restrictions;
 243   TA_Style fallback_style;
 244   TA_Script default_script;
 245   FT_Bool symbol;
 246   FT_Bool dehint;
 247   FT_Bool debug;
 248 };
 249
 250
 251 #include "tatables.h"
 252 #include "tabytecode.h"
 253
 254
 255 const char*
 256 TA_get_error_message(FT_Error error);
 257
 258 void
 259 TA_get_current_time(FT_ULong* high,
 260                     FT_ULong* low);
 261
 262 FT_Byte*
 263 TA_build_push(FT_Byte* bufp,
 264               FT_UInt* args,
 265               FT_UInt num_args,
 266               FT_Bool need_words,
 267               FT_Bool optimize);
 268
 269 FT_Error
 270 TA_font_init(FONT* font);
 271 void
 272 TA_font_unload(FONT* font,
 273                const char* in_buf,
 274                char** out_bufp);
 275
 276 FT_Error
 277 TA_font_file_read(FONT* font,
 278                   FILE* in_file);
 279 FT_Error
 280 TA_font_file_write(FONT* font,
 281                    FILE* out_file);
 282
 283 FT_Error
 284 TA_sfnt_build_glyph_instructions(SFNT* sfnt,
 285                                  FONT* font,
 286                                  FT_Long idx);
 287
 288 FT_Error
 289 TA_sfnt_split_into_SFNT_tables(SFNT* sfnt,
 290                                FONT* font);
 291
 292 FT_Error
 293 TA_sfnt_build_cvt_table(SFNT* sfnt,
 294                         FONT* font);
 295
 296 FT_Error
 297 TA_table_build_DSIG(FT_Byte** DSIG);
 298
 299 FT_Error
 300 TA_sfnt_build_fpgm_table(SFNT* sfnt,
 301                          FONT* font);
 302
 303 FT_Error
 304 TA_sfnt_build_gasp_table(SFNT* sfnt,
 305                          FONT* font);
 306
 307 FT_Error
 308 TA_sfnt_split_glyf_table(SFNT* sfnt,
 309                          FONT* font);
 310 FT_Error
 311 TA_sfnt_build_glyf_table(SFNT* sfnt,
 312                          FONT* font);
 313 FT_Error
 314 TA_sfnt_create_glyf_data(SFNT* sfnt,
 315                          FONT* font);
 316 FT_Error
 317 TA_sfnt_handle_coverage(SFNT* sfnt,
 318                         FONT* font);
 319 void
 320 TA_sfnt_adjust_coverage(SFNT* sfnt,
 321                         FONT* font);
 322 #if 0
 323 void
 324 TA_sfnt_copy_master_coverage(SFNT* sfnt,
 325                              FONT* font);
 326 #endif
 327
 328 FT_Error
 329 TA_sfnt_update_GPOS_table(SFNT* sfnt,
 330                           FONT* font);
 331
 332 FT_Error
 333 TA_sfnt_update_hmtx_table(SFNT* sfnt,
 334                           FONT* font);
 335
 336 FT_Error
 337 TA_sfnt_build_loca_table(SFNT* sfnt,
 338                          FONT* font);
 339
 340 FT_Error
 341 TA_sfnt_update_maxp_table(SFNT* sfnt,
 342                           FONT* font);
 343
 344 FT_Error
 345 TA_sfnt_update_post_table(SFNT* sfnt,
 346                           FONT* font);
 347
 348 FT_Error
 349 TA_sfnt_update_name_table(SFNT* sfnt,
 350                           FONT* font);
 351
 352 FT_Error
 353 TA_sfnt_build_prep_table(SFNT* sfnt,
 354                          FONT* font);
 355
 356 FT_Error
 357 TA_sfnt_build_TTF_header(SFNT* sfnt,
 358                          FONT* font,
 359                          FT_Byte** header_buf,
 360                          FT_ULong* header_len,
 361                          FT_Int do_complete);
 362 FT_Error
 363 TA_font_build_TTF(FONT* font);
 364
 365 FT_Error
 366 TA_font_build_TTC(FONT* font);
 367
 368 #endif /* __TA_H__ */
 369
 370 /* end of ta.h */