lib/ttfautohint.c

   1 /* ttfautohint.c */
   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 /* This file needs FreeType 2.4.5 or newer. */
  17
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <ctype.h>
  22
  23 #include "ta.h"
  24
  25
  26 #define COMPARE(str) \
  27           (len == (sizeof (str) - 1) \
  28            && !strncmp(start, str, sizeof (str) - 1))
  29
  30
  31 void
  32 TA_sfnt_set_properties(SFNT* sfnt,
  33                        FONT* font)
  34 {
  35   TA_FaceGlobals globals = (TA_FaceGlobals)sfnt->face->autohint.data;
  36
  37
  38   globals->increase_x_height = font->increase_x_height;
  39 }
  40
  41
  42 TA_Error
  43 TTF_autohint(const char* options,
  44              ...)
  45 {
  46   va_list ap;
  47
  48   FONT* font;
  49   FT_Long i;
  50
  51   TA_Error error;
  52   const char* error_string = NULL;
  53   unsigned int errlinenum = 0;
  54   char* errline = NULL;
  55   char* errpos = NULL;
  56   FT_Bool free_errline = 0;
  57
  58   FILE* in_file = NULL;
  59   FILE* out_file = NULL;
  60   FILE* deltas_file = NULL;
  61
  62   const char* in_buf = NULL;
  63   size_t in_len = 0;
  64   char** out_bufp = NULL;
  65   size_t* out_lenp = NULL;
  66   const char* deltas_buf = NULL;
  67   size_t deltas_len = 0;
  68
  69   const unsigned char** error_stringp = NULL;
  70
  71   Deltas* deltas = NULL;
  72
  73   FT_Long hinting_range_min = -1;
  74   FT_Long hinting_range_max = -1;
  75   FT_Long hinting_limit = -1;
  76   FT_Long increase_x_height = -1;
  77
  78   const char* x_height_snapping_exceptions_string = NULL;
  79   number_range* x_height_snapping_exceptions = NULL;
  80
  81   FT_Long fallback_stem_width = 0;
  82
  83   FT_Bool gray_strong_stem_width = 0;
  84   FT_Bool gdi_cleartype_strong_stem_width = 1;
  85   FT_Bool dw_cleartype_strong_stem_width = 0;
  86
  87   TA_Progress_Func progress = NULL;
  88   void* progress_data = NULL;
  89   TA_Error_Func err = NULL;
  90   void* err_data = NULL;
  91   TA_Info_Func info = NULL;
  92   void* info_data = NULL;
  93
  94   FT_Bool windows_compatibility = 0;
  95   FT_Bool ignore_restrictions = 0;
  96   FT_Bool adjust_subglyphs = 0;
  97   FT_Bool hint_composites = 0;
  98   FT_Bool symbol = 0;
  99
 100   const char* fallback_script_string = NULL;
 101   const char* default_script_string = NULL;
 102   TA_Style fallback_style = TA_STYLE_NONE_DFLT;
 103   TA_Script default_script = TA_SCRIPT_LATN;
 104
 105   FT_Bool dehint = 0;
 106   FT_Bool debug = 0;
 107
 108   const char* op;
 109
 110   if (!options || !*options)
 111   {
 112     error = FT_Err_Invalid_Argument;
 113     goto Err1;
 114   }
 115
 116   /* XXX */
 117   va_start(ap, options);
 118
 119   op = options;
 120
 121   for(;;)
 122   {
 123     const char* start;
 124     size_t len;
 125
 126
 127     start = op;
 128
 129     /* search comma */
 130     while (*op && *op != ',')
 131       op++;
 132
 133     /* remove leading whitespace */
 134     while (isspace(*start))
 135       start++;
 136
 137     /* check for empty option */
 138     if (start == op)
 139       goto End;
 140
 141     len = op - start;
 142
 143     /* the `COMPARE' macro uses `len' and `start' */
 144
 145     /* handle options -- don't forget to update parameter dump below! */
 146     if (COMPARE("adjust-subglyphs"))
 147       adjust_subglyphs = (FT_Bool)va_arg(ap, FT_Int);
 148     else if (COMPARE("debug"))
 149       debug = (FT_Bool)va_arg(ap, FT_Int);
 150     else if (COMPARE("default-script"))
 151       default_script_string = va_arg(ap, const char*);
 152     else if (COMPARE("dehint"))
 153       dehint = (FT_Bool)va_arg(ap, FT_Int);
 154     else if (COMPARE("deltas-buffer"))
 155     {
 156       deltas_file = NULL;
 157       deltas_buf = va_arg(ap, const char*);
 158     }
 159     else if (COMPARE("deltas-buffer-len"))
 160     {
 161       deltas_file = NULL;
 162       deltas_len = va_arg(ap, size_t);
 163     }
 164     else if (COMPARE("deltas-file"))
 165     {
 166       deltas_file = va_arg(ap, FILE*);
 167       deltas_buf = NULL;
 168       deltas_len = 0;
 169     }
 170     else if (COMPARE("dw-cleartype-strong-stem-width"))
 171       dw_cleartype_strong_stem_width = (FT_Bool)va_arg(ap, FT_Int);
 172     else if (COMPARE("error-callback"))
 173       err = va_arg(ap, TA_Error_Func);
 174     else if (COMPARE("error-callback-data"))
 175       err_data = va_arg(ap, void*);
 176     else if (COMPARE("error-string"))
 177       error_stringp = va_arg(ap, const unsigned char**);
 178     else if (COMPARE("fallback-script"))
 179       fallback_script_string = va_arg(ap, const char*);
 180     else if (COMPARE("fallback-stem-width"))
 181       fallback_stem_width = (FT_Long)va_arg(ap, FT_UInt);
 182     else if (COMPARE("gdi-cleartype-strong-stem-width"))
 183       gdi_cleartype_strong_stem_width = (FT_Bool)va_arg(ap, FT_Int);
 184     else if (COMPARE("gray-strong-stem-width"))
 185       gray_strong_stem_width = (FT_Bool)va_arg(ap, FT_Int);
 186     else if (COMPARE("hinting-limit"))
 187       hinting_limit = (FT_Long)va_arg(ap, FT_UInt);
 188     else if (COMPARE("hinting-range-max"))
 189       hinting_range_max = (FT_Long)va_arg(ap, FT_UInt);
 190     else if (COMPARE("hinting-range-min"))
 191       hinting_range_min = (FT_Long)va_arg(ap, FT_UInt);
 192     else if (COMPARE("hint-composites"))
 193       hint_composites = (FT_Bool)va_arg(ap, FT_Int);
 194     else if (COMPARE("ignore-restrictions"))
 195       ignore_restrictions = (FT_Bool)va_arg(ap, FT_Int);
 196     else if (COMPARE("in-buffer"))
 197     {
 198       in_file = NULL;
 199       in_buf = va_arg(ap, const char*);
 200     }
 201     else if (COMPARE("in-buffer-len"))
 202     {
 203       in_file = NULL;
 204       in_len = va_arg(ap, size_t);
 205     }
 206     else if (COMPARE("in-file"))
 207     {
 208       in_file = va_arg(ap, FILE*);
 209       in_buf = NULL;
 210       in_len = 0;
 211     }
 212     else if (COMPARE("increase-x-height"))
 213       increase_x_height = (FT_Long)va_arg(ap, FT_UInt);
 214     else if (COMPARE("info-callback"))
 215       info = va_arg(ap, TA_Info_Func);
 216     else if (COMPARE("info-callback-data"))
 217       info_data = va_arg(ap, void*);
 218     else if (COMPARE("out-buffer"))
 219     {
 220       out_file = NULL;
 221       out_bufp = va_arg(ap, char**);
 222     }
 223     else if (COMPARE("out-buffer-len"))
 224     {
 225       out_file = NULL;
 226       out_lenp = va_arg(ap, size_t*);
 227     }
 228     else if (COMPARE("out-file"))
 229     {
 230       out_file = va_arg(ap, FILE*);
 231       out_bufp = NULL;
 232       out_lenp = NULL;
 233     }
 234     else if (COMPARE("pre-hinting"))
 235       adjust_subglyphs = (FT_Bool)va_arg(ap, FT_Int);
 236     else if (COMPARE("progress-callback"))
 237       progress = va_arg(ap, TA_Progress_Func);
 238     else if (COMPARE("progress-callback-data"))
 239       progress_data = va_arg(ap, void*);
 240     else if (COMPARE("symbol"))
 241       symbol = (FT_Bool)va_arg(ap, FT_Int);
 242     else if (COMPARE("windows-compatibility"))
 243       windows_compatibility = (FT_Bool)va_arg(ap, FT_Int);
 244     else if (COMPARE("x-height-snapping-exceptions"))
 245       x_height_snapping_exceptions_string = va_arg(ap, const char*);
 246     else
 247     {
 248       error = TA_Err_Unknown_Argument;
 249       goto Err1;
 250     }
 251
 252   End:
 253     if (!*op)
 254       break;
 255     op++;
 256   }
 257
 258   va_end(ap);
 259
 260   /* check options */
 261
 262   if (!(in_file
 263         || (in_buf && in_len)))
 264   {
 265     error = FT_Err_Invalid_Argument;
 266     goto Err1;
 267   }
 268
 269   if (!(out_file
 270         || (out_bufp && out_lenp)))
 271   {
 272     error = FT_Err_Invalid_Argument;
 273     goto Err1;
 274   }
 275
 276   font = (FONT*)calloc(1, sizeof (FONT));
 277   if (!font)
 278   {
 279     error = FT_Err_Out_Of_Memory;
 280     goto Err1;
 281   }
 282
 283   if (dehint)
 284     goto No_check;
 285
 286   if (hinting_range_min >= 0 && hinting_range_min < 2)
 287   {
 288     error = FT_Err_Invalid_Argument;
 289     goto Err1;
 290   }
 291   if (hinting_range_min < 0)
 292     hinting_range_min = TA_HINTING_RANGE_MIN;
 293
 294   if (hinting_range_max >= 0 && hinting_range_max < hinting_range_min)
 295   {
 296     error = FT_Err_Invalid_Argument;
 297     goto Err1;
 298   }
 299   if (hinting_range_max < 0)
 300     hinting_range_max = TA_HINTING_RANGE_MAX;
 301
 302   /* value 0 is valid */
 303   if (hinting_limit > 0 && hinting_limit < hinting_range_max)
 304   {
 305     error = FT_Err_Invalid_Argument;
 306     goto Err1;
 307   }
 308   if (hinting_limit < 0)
 309     hinting_limit = TA_HINTING_LIMIT;
 310
 311   if (increase_x_height > 0
 312       && increase_x_height < TA_PROP_INCREASE_X_HEIGHT_MIN)
 313   {
 314     error = FT_Err_Invalid_Argument;
 315     goto Err1;
 316   }
 317   if (increase_x_height < 0)
 318     increase_x_height = TA_INCREASE_X_HEIGHT;
 319
 320   if (fallback_script_string)
 321   {
 322     int i;
 323
 324
 325     for (i = 0; i < TA_STYLE_MAX; i++)
 326     {
 327       TA_StyleClass style_class = ta_style_classes[i];
 328
 329
 330       if (style_class->coverage == TA_COVERAGE_DEFAULT
 331           && !strcmp(script_names[style_class->script],
 332                      fallback_script_string))
 333         break;
 334     }
 335     if (i == TA_STYLE_MAX)
 336     {
 337       error = FT_Err_Invalid_Argument;
 338       goto Err1;
 339     }
 340
 341     fallback_style = (TA_Style)i;
 342   }
 343
 344   if (default_script_string)
 345   {
 346     int i;
 347
 348
 349     for (i = 0; i < TA_SCRIPT_MAX; i++)
 350     {
 351       if (!strcmp(script_names[i], default_script_string))
 352         break;
 353     }
 354     if (i == TA_SCRIPT_MAX)
 355     {
 356       error = FT_Err_Invalid_Argument;
 357       goto Err1;
 358     }
 359
 360     default_script = (TA_Script)i;
 361   }
 362
 363   if (x_height_snapping_exceptions_string)
 364   {
 365     const char* s = number_set_parse(x_height_snapping_exceptions_string,
 366                                      &x_height_snapping_exceptions,
 367                                      TA_PROP_INCREASE_X_HEIGHT_MIN,
 368                                      0x7FFF);
 369     if (*s)
 370     {
 371       /* we map numberset.h's error codes to values starting with 0x100 */
 372       error = 0x100 - (FT_Error)x_height_snapping_exceptions;
 373       errlinenum = 0;
 374       errline = (char*)x_height_snapping_exceptions_string;
 375       errpos = (char*)s;
 376
 377       goto Err1;
 378     }
 379   }
 380
 381   font->hinting_range_min = (FT_UInt)hinting_range_min;
 382   font->hinting_range_max = (FT_UInt)hinting_range_max;
 383   font->hinting_limit = (FT_UInt)hinting_limit;
 384   font->increase_x_height = increase_x_height;
 385   font->x_height_snapping_exceptions = x_height_snapping_exceptions;
 386   font->fallback_stem_width = (FT_UInt)fallback_stem_width;
 387
 388   font->gray_strong_stem_width = gray_strong_stem_width;
 389   font->gdi_cleartype_strong_stem_width = gdi_cleartype_strong_stem_width;
 390   font->dw_cleartype_strong_stem_width = dw_cleartype_strong_stem_width;
 391
 392   font->windows_compatibility = windows_compatibility;
 393   font->ignore_restrictions = ignore_restrictions;
 394   font->adjust_subglyphs = adjust_subglyphs;
 395   font->hint_composites = hint_composites;
 396   font->fallback_style = fallback_style;
 397   font->default_script = default_script;
 398   font->symbol = symbol;
 399
 400 No_check:
 401   font->progress = progress;
 402   font->progress_data = progress_data;
 403   font->info = info;
 404   font->info_data = info_data;
 405
 406   font->debug = debug;
 407   font->dehint = dehint;
 408
 409   font->gasp_idx = MISSING;
 410
 411   /* start with processing the data */
 412
 413   if (in_file)
 414   {
 415     error = TA_font_file_read(font, in_file);
 416     if (error)
 417       goto Err;
 418   }
 419   else
 420   {
 421     /* a valid TTF can never be that small */
 422     if (in_len < 100)
 423     {
 424       error = TA_Err_Invalid_Font_Type;
 425       goto Err1;
 426     }
 427     font->in_buf = (FT_Byte*)in_buf;
 428     font->in_len = in_len;
 429   }
 430
 431   if (deltas_file)
 432   {
 433     error = TA_deltas_file_read(font, deltas_file);
 434     if (error)
 435       goto Err;
 436   }
 437   else if (deltas_buf)
 438   {
 439     font->deltas_buf = (char*)deltas_buf;
 440     font->deltas_len = deltas_len;
 441   }
 442
 443   error = TA_font_init(font);
 444   if (error)
 445     goto Err;
 446
 447   if (font->debug)
 448   {
 449     _ta_debug = 1;
 450     _ta_debug_global = 1;
 451   }
 452
 453   /* we do some loops over all subfonts -- */
 454   /* to process options early, just start with loading all of them */
 455   for (i = 0; i < font->num_sfnts; i++)
 456   {
 457     SFNT* sfnt = &font->sfnts[i];
 458     FT_UInt idx;
 459
 460
 461     error = FT_New_Memory_Face(font->lib, font->in_buf, font->in_len,
 462                                i, &sfnt->face);
 463
 464     /* assure that the font hasn't been already processed by ttfautohint; */
 465     /* another, more thorough check is done in TA_glyph_parse_simple */
 466     idx = FT_Get_Name_Index(sfnt->face, (FT_String*)TTFAUTOHINT_GLYPH);
 467     if (idx)
 468     {
 469       error = TA_Err_Already_Processed;
 470       goto Err;
 471     }
 472
 473     if (error)
 474       goto Err;
 475   }
 476
 477   /* process delta exceptions data */
 478   error = TA_deltas_parse_buffer(font,
 479                                  &deltas,
 480                                  &errlinenum, &errline, &errpos);
 481   if (error)
 482   {
 483     free_errline = 1;
 484     goto Err;
 485   }
 486
 487   /* now we are able to dump all parameters */
 488   if (debug)
 489   {
 490     error = TA_font_dump_parameters(font, stderr, deltas, dehint, 1);
 491     if (error)
 492       goto Err;
 493   }
 494
 495   error = TA_deltas_build_tree(font, deltas);
 496   if (error)
 497     goto Err;
 498
 499   /* loop again over subfonts and continue processing */
 500   for (i = 0; i < font->num_sfnts; i++)
 501   {
 502     SFNT* sfnt = &font->sfnts[i];
 503
 504
 505     error = TA_sfnt_split_into_SFNT_tables(sfnt, font);
 506     if (error)
 507       goto Err;
 508
 509     /* check permission */
 510     if (sfnt->OS2_idx != MISSING)
 511     {
 512       SFNT_Table* OS2_table = &font->tables[sfnt->OS2_idx];
 513
 514
 515       /* check lower byte of the `fsType' field */
 516       if (OS2_table->buf[OS2_FSTYPE_OFFSET + 1] == 0x02
 517           && !font->ignore_restrictions)
 518       {
 519         error = TA_Err_Missing_Legal_Permission;
 520         goto Err;
 521       }
 522     }
 523
 524     if (font->dehint)
 525     {
 526       error = TA_sfnt_split_glyf_table(sfnt, font);
 527       if (error)
 528         goto Err;
 529     }
 530     else
 531     {
 532       if (font->adjust_subglyphs)
 533         error = TA_sfnt_create_glyf_data(sfnt, font);
 534       else
 535         error = TA_sfnt_split_glyf_table(sfnt, font);
 536       if (error)
 537         goto Err;
 538
 539       /* this call creates a `globals' object... */
 540       error = TA_sfnt_handle_coverage(sfnt, font);
 541       if (error)
 542         goto Err;
 543
 544       /* ... so that we now can initialize its properties */
 545       TA_sfnt_set_properties(sfnt, font);
 546     }
 547   }
 548
 549   if (!font->dehint)
 550   {
 551     for (i = 0; i < font->num_sfnts; i++)
 552     {
 553       SFNT* sfnt = &font->sfnts[i];
 554
 555
 556       TA_sfnt_adjust_coverage(sfnt, font);
 557     }
 558   }
 559
 560 #if 0
 561   /* this code is here for completeness -- */
 562   /* right now, `glyf' tables get hinted only once, */
 563   /* and referring subfonts simply reuse it, */
 564   /* but this might change in the future */
 565
 566   if (!font->dehint)
 567   {
 568     for (i = 0; i < font->num_sfnts; i++)
 569     {
 570       SFNT* sfnt = &font->sfnts[i];
 571
 572
 573       TA_sfnt_copy_master_coverage(sfnt, font);
 574     }
 575   }
 576 #endif
 577
 578   /* loop again over subfonts */
 579   for (i = 0; i < font->num_sfnts; i++)
 580   {
 581     SFNT* sfnt = &font->sfnts[i];
 582
 583
 584     error = ta_loader_init(font);
 585     if (error)
 586       goto Err;
 587
 588     error = TA_sfnt_build_gasp_table(sfnt, font);
 589     if (error)
 590       goto Err;
 591     if (!font->dehint)
 592     {
 593       error = TA_sfnt_build_cvt_table(sfnt, font);
 594       if (error)
 595         goto Err;
 596       error = TA_sfnt_build_fpgm_table(sfnt, font);
 597       if (error)
 598         goto Err;
 599       error = TA_sfnt_build_prep_table(sfnt, font);
 600       if (error)
 601         goto Err;
 602     }
 603     error = TA_sfnt_build_glyf_table(sfnt, font);
 604     if (error)
 605       goto Err;
 606     error = TA_sfnt_build_loca_table(sfnt, font);
 607     if (error)
 608       goto Err;
 609
 610     if (font->loader)
 611       ta_loader_done(font);
 612   }
 613
 614   for (i = 0; i < font->num_sfnts; i++)
 615   {
 616     SFNT* sfnt = &font->sfnts[i];
 617
 618
 619     error = TA_sfnt_update_maxp_table(sfnt, font);
 620     if (error)
 621       goto Err;
 622
 623     if (!font->dehint)
 624     {
 625       /* we add one glyph for composites */
 626       if (sfnt->max_components
 627           && !font->adjust_subglyphs
 628           && font->hint_composites)
 629       {
 630         error = TA_sfnt_update_hmtx_table(sfnt, font);
 631         if (error)
 632           goto Err;
 633         error = TA_sfnt_update_post_table(sfnt, font);
 634         if (error)
 635           goto Err;
 636         error = TA_sfnt_update_GPOS_table(sfnt, font);
 637         if (error)
 638           goto Err;
 639       }
 640     }
 641
 642     if (font->info)
 643     {
 644       /* add info about ttfautohint to the version string */
 645       error = TA_sfnt_update_name_table(sfnt, font);
 646       if (error)
 647         goto Err;
 648     }
 649   }
 650
 651   if (font->num_sfnts == 1)
 652     error = TA_font_build_TTF(font);
 653   else
 654     error = TA_font_build_TTC(font);
 655   if (error)
 656     goto Err;
 657
 658   if (out_file)
 659   {
 660     error = TA_font_file_write(font, out_file);
 661     if (error)
 662       goto Err;
 663   }
 664   else
 665   {
 666     *out_bufp = (char*)font->out_buf;
 667     *out_lenp = font->out_len;
 668   }
 669
 670   error = TA_Err_Ok;
 671
 672 Err:
 673   TA_deltas_free(deltas);
 674   TA_deltas_free_tree(font);
 675   TA_font_unload(font, in_buf, out_bufp, deltas_buf);
 676
 677 Err1:
 678   error_string = TA_get_error_message(error);
 679
 680   if (error_stringp)
 681     *error_stringp = (const unsigned char*)error_string;
 682
 683   if (err)
 684     err(error,
 685         error_string,
 686         errlinenum,
 687         errline,
 688         errpos,
 689         err_data);
 690
 691   if (free_errline)
 692     free(errline);
 693
 694   return error;
 695 }
 696
 697 /* end of ttfautohint.c */