lily/ttf.cc

   1 /*
   2   ttf.cc --  implement ttf -> pfa routine.
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2005--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "freetype.hh"
  10
  11 #include <freetype/tttables.h>
  12
  13 #include "memory-stream.hh"
  14 #include "warn.hh"
  15 #include "lily-guile.hh"
  16 #include "main.hh"
  17 #include "open-type-font.hh"
  18
  19
  20 Index_to_charcode_map
  21 make_index_to_charcode_map (FT_Face face)
  22 {
  23   Index_to_charcode_map m;
  24   FT_ULong charcode;
  25   FT_UInt gindex;
  26
  27   FT_CharMap current_cmap = face->charmap;
  28   FT_Select_Charmap (face, FT_ENCODING_UNICODE);
  29
  30   int j = 0;
  31   for (charcode = FT_Get_First_Char (face, &gindex); gindex != 0;
  32        charcode = FT_Get_Next_Char (face, charcode, &gindex))
  33     {
  34       m[gindex] = charcode;
  35       j ++;
  36     }
  37   FT_Set_Charmap (face, current_cmap);
  38
  39   return m;
  40 }
  41
  42 /*
  43   Based on ttfps by Juliusz Chroboczek
  44 */
  45 static void
  46 print_header (void *out, FT_Face face)
  47 {
  48   lily_cookie_fprintf (out, "%%!PS-TrueTypeFont\n");
  49
  50   TT_Postscript *pt
  51     = (TT_Postscript *) FT_Get_Sfnt_Table (face, ft_sfnt_post);
  52
  53   if (pt->maxMemType42)
  54     lily_cookie_fprintf (out, "%%%%VMUsage: %d %d\n", 0, 0);
  55
  56   lily_cookie_fprintf (out, "%d dict begin\n", 11);
  57   lily_cookie_fprintf (out, "/FontName /%s def\n",
  58                        FT_Get_Postscript_Name (face));
  59
  60   lily_cookie_fprintf (out, "/Encoding StandardEncoding def\n");
  61   lily_cookie_fprintf (out, "/PaintType 0 def\n");
  62   lily_cookie_fprintf (out, "/FontMatrix [1 0 0 1 0 0] def\n");
  63
  64   TT_Header *ht
  65     = (TT_Header *)FT_Get_Sfnt_Table (face, ft_sfnt_head);
  66
  67   lily_cookie_fprintf (out, "/FontBBox [%lf %lf %lf %lf] def\n",
  68                        float (ht->xMin) / ht->Units_Per_EM,
  69                        float (ht->yMin) / ht->Units_Per_EM,
  70                        float (ht->xMax) / ht->Units_Per_EM,
  71                        float (ht->yMax) / ht->Units_Per_EM);
  72
  73   lily_cookie_fprintf (out, "/FontType 42 def\n");
  74   lily_cookie_fprintf (out, "/FontInfo 8 dict dup begin\n");
  75   lily_cookie_fprintf (out, "/version (%.3f) def\n",
  76                        ht->Font_Revision / 65536.0);
  77
  78 #if 0
  79   if (strings[0])
  80     {
  81       lily_cookie_fprintf (out, "/Notice (");
  82       fputpss (strings[0], out);
  83       lily_cookie_fprintf (out, ") def\n");
  84     }
  85   if (strings[4])
  86     {
  87       lily_cookie_fprintf (out, "/FullName (");
  88       fputpss (strings[4], out);
  89       lily_cookie_fprintf (out, ") def\n");
  90     }
  91   if (strings[1])
  92     {
  93       lily_cookie_fprintf (out, "/FamilyName (");
  94       fputpss (strings[1], out);
  95       lily_cookie_fprintf (out, ") def\n");
  96     }
  97 #endif
  98
  99   lily_cookie_fprintf (out, "/isFixedPitch %s def\n",
 100                        pt->isFixedPitch ? "true" : "false");
 101   lily_cookie_fprintf (out, "/UnderlinePosition %lf def\n",
 102                        float (pt->underlinePosition) / ht->Units_Per_EM);
 103   lily_cookie_fprintf (out, "/UnderlineThickness %lf def\n",
 104                        float (pt->underlineThickness) / ht->Units_Per_EM);
 105   lily_cookie_fprintf (out, "end readonly def\n");
 106 }
 107
 108 #define CHUNKSIZE 65534
 109
 110 const FT_ULong FT_ENC_TAG (glyf_tag, 'g', 'l', 'y', 'f');
 111 const FT_ULong FT_ENC_TAG (head_tag, 'h', 'e', 'a', 'd');
 112 const FT_ULong FT_ENC_TAG (loca_tag, 'l', 'o', 'c', 'a');
 113
 114 static
 115 void t42_write_table (void *out, FT_Face face, unsigned char const *buffer,
 116                       size_t s, bool is_glyf,
 117                       FT_ULong head_length, FT_ULong loca_length)
 118 {
 119   vector<FT_UShort> chunks;
 120
 121   if (is_glyf)
 122     {
 123       /* compute chunk sizes */
 124       unsigned char *head_buf = new unsigned char[head_length];
 125       FT_Error error = FT_Load_Sfnt_Table (face, head_tag, 0, head_buf, NULL);
 126       if (error)
 127         programming_error ("FT_Load_Sfnt_Table (): error.");
 128
 129       /* we access the lower byte of indexToLocFormat */
 130       bool long_offsets = head_buf[4*4 + 2*2 + 2*8 + 4*2 + 3*2 + 1] == 1;
 131
 132       delete[] head_buf;
 133
 134       unsigned char *loca_buf = new unsigned char[loca_length];
 135       error = FT_Load_Sfnt_Table (face, loca_tag, 0, loca_buf, NULL);
 136       if (error)
 137         programming_error ("FT_Load_Sfnt_Table (): error.");
 138
 139       unsigned char *p = loca_buf;
 140       unsigned char *endp = loca_buf + loca_length;
 141
 142       FT_ULong offset = 0, last_offset = 0, last_chunk = 0;
 143       while (p < endp)
 144       {
 145         if (long_offsets)
 146           {
 147             offset = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
 148             p += 4;
 149           }
 150         else
 151           {
 152             offset = ((p[0] << 8) | p[1]) << 1;
 153             p += 2;
 154           }
 155         if (offset > last_offset + CHUNKSIZE)
 156           {
 157             if (last_chunk != last_offset)
 158               chunks.push_back (last_offset - last_chunk);
 159             /*
 160               a single glyph with more than 64k data
 161               is a pathological case but...
 162              */
 163             FT_ULong rest = offset - last_offset;
 164             while (rest > CHUNKSIZE)
 165               {
 166                 chunks.push_back (CHUNKSIZE);
 167                 rest -= CHUNKSIZE;
 168               }
 169             chunks.push_back (rest);
 170             last_chunk = offset;
 171           }
 172         else if (offset > last_chunk + CHUNKSIZE)
 173           {
 174             chunks.push_back (last_offset - last_chunk);
 175             last_chunk = last_offset;
 176           }
 177
 178         last_offset = offset;
 179       }
 180       chunks.push_back (s - last_chunk);
 181
 182       delete[] loca_buf;
 183     }
 184   else if (s > CHUNKSIZE)
 185     {
 186       FT_ULong rest = s;
 187       while (rest > CHUNKSIZE)
 188         {
 189           chunks.push_back (CHUNKSIZE);
 190           rest -= CHUNKSIZE;
 191         }
 192       chunks.push_back (rest);
 193     }
 194   else
 195     chunks.push_back (CHUNKSIZE);
 196
 197   lily_cookie_fprintf (out, "\n"
 198                             " <");
 199
 200   int l = 0;
 201   static char xdigits[] = "0123456789ABCDEF";
 202
 203   int cur_chunk_idx = 0;
 204   for (size_t j = 0; j < s; j++)
 205     {
 206       if (l >= chunks[cur_chunk_idx])
 207         {
 208           lily_cookie_fprintf (out, "\n"
 209                                     " 00>\n"
 210                                     " <");
 211           l = 0;
 212           cur_chunk_idx ++;
 213         }
 214
 215       if (l % 31 == 0)
 216         lily_cookie_fprintf (out, "\n"
 217                                   "  ");
 218
 219       /* lily_cookie_fprintf (out,"%02X",(int)buffer[j]) is too slow */
 220       lily_cookie_putc (xdigits[(buffer[j] & 0xF0) >> 4], out);
 221       lily_cookie_putc (xdigits[buffer[j] & 0x0F], out);
 222
 223       l ++;
 224     }
 225
 226   /* pad to four-byte boundary */
 227   while ((s ++) % 4 != 0)
 228     lily_cookie_fprintf (out, "00");
 229
 230   lily_cookie_fprintf (out, "\n"
 231                             "  00\n"
 232                             " >");
 233 }
 234
 235 static void
 236 print_body (void *out, FT_Face face)
 237 {
 238   FT_UInt idx = 0;
 239   FT_ULong head_length = 0, loca_length = 0;
 240   FT_ULong tag, length;
 241   vector<FT_ULong> lengths, tags;
 242
 243   /*
 244     we must build our own TTF header -- the original font
 245     might be a TTC where tables are not contiguous, or the font
 246     contains tables which aren't indexed at all
 247    */
 248   while (FT_Sfnt_Table_Info (face, idx, &tag, &length)
 249          != FT_Err_Table_Missing)
 250   {
 251     lengths.push_back (length);
 252     tags.push_back (tag);
 253     if (tag == head_tag)
 254       head_length = length;
 255     else if (tag == loca_tag)
 256       loca_length = length;
 257     idx ++;
 258   }
 259
 260   FT_ULong hlength = 12 + 16 * idx;
 261
 262   unsigned char *hbuf = new unsigned char[hlength];
 263   unsigned char *p;
 264
 265   hbuf[0] = 0x00;                       /* version */
 266   hbuf[1] = 0x01;
 267   hbuf[2] = 0x00;
 268   hbuf[3] = 0x00;
 269   hbuf[4] = (idx & 0xFF00) >> 8;        /* numTables */
 270   hbuf[5] = idx & 0x00FF;
 271
 272   FT_UInt searchRange, entrySelector, rangeShift;
 273   FT_UInt i, j;
 274   for (i = 1, j = 2; j <= idx; i++, j <<= 1)
 275     ;
 276   entrySelector = i - 1;
 277   searchRange = 0x10 << entrySelector;
 278   rangeShift = (idx << 4) - searchRange;
 279
 280   hbuf[6] = (searchRange & 0xFF00) >> 8;
 281   hbuf[7] = searchRange & 0x00FF;
 282   hbuf[8] = (entrySelector & 0xFF00) >> 8;
 283   hbuf[9] = entrySelector & 0x00FF;
 284   hbuf[10] = (rangeShift & 0xFF00) >> 8;
 285   hbuf[11] = rangeShift & 0x00FF;
 286
 287   p = &hbuf[12];
 288
 289   FT_ULong checksum, font_checksum = 0;
 290
 291   FT_ULong offset = hlength;            /* first table offset */
 292
 293   for (FT_UInt i = 0; i < idx; i++)
 294   {
 295     /* here, the buffer length must be a multiple of 4 */
 296     FT_ULong len = (lengths[i] + 3) & ~3;
 297     unsigned char *buf = new unsigned char[len];
 298
 299     buf[len - 1] = 0x00;                /* assure padding with zeros */
 300     buf[len - 2] = 0x00;
 301     buf[len - 3] = 0x00;
 302
 303     FT_Error error = FT_Load_Sfnt_Table (face, tags[i], 0, buf, NULL);
 304     if (error)
 305       programming_error ("FT_Load_Sfnt_Table (): error.");
 306
 307     if (tag == head_tag)
 308       {
 309         /*
 310           first pass of computing the font checksum
 311           needs checkSumAdjustment = 0
 312          */
 313         buf[8] = 0x00;
 314         buf[9] = 0x00;
 315         buf[10] = 0x00;
 316         buf[11] = 0x00;
 317       }
 318
 319     checksum = 0;
 320     unsigned char *endq = buf + len;
 321     for (unsigned char *q = buf; q < endq; q += 4)
 322       checksum += (q[0] << 24) | (q[1] << 16) | (q[2] << 8) | q[3];
 323     font_checksum += checksum;
 324
 325     delete[] buf;
 326
 327     *(p++) = (tags[i] & 0xFF000000UL) >> 24;
 328     *(p++) = (tags[i] & 0x00FF0000UL) >> 16;
 329     *(p++) = (tags[i] & 0x0000FF00UL) >> 8;
 330     *(p++) = tags[i] & 0x000000FFUL;
 331
 332     *(p++) = (checksum & 0xFF000000UL) >> 24;
 333     *(p++) = (checksum & 0x00FF0000UL) >> 16;
 334     *(p++) = (checksum & 0x0000FF00UL) >> 8;
 335     *(p++) = checksum & 0x000000FFUL;
 336
 337     *(p++) = (offset & 0xFF000000UL) >> 24;
 338     *(p++) = (offset & 0x00FF0000UL) >> 16;
 339     *(p++) = (offset & 0x0000FF00UL) >> 8;
 340     *(p++) = offset & 0x000000FFUL;
 341
 342     *(p++) = (lengths[i] & 0xFF000000UL) >> 24;
 343     *(p++) = (lengths[i] & 0x00FF0000UL) >> 16;
 344     *(p++) = (lengths[i] & 0x0000FF00UL) >> 8;
 345     *(p++) = lengths[i] & 0x000000FFUL;
 346
 347     /* offset must be a multiple of 4 */
 348     offset += (lengths[i] + 3) & ~3;
 349   }
 350
 351   /* add checksum of TTF header */
 352   checksum = 0;
 353   for (unsigned char *q = hbuf; q < p; q += 4)
 354     checksum += (q[0] << 24) | (q[1] << 16) | (q[2] << 8) | q[3];
 355   font_checksum += checksum;
 356   font_checksum = 0xB1B0AFBAUL - font_checksum;
 357
 358   /*
 359     see Adobe technical note 5012.Type42_Spec.pdf for details how
 360     the /sfnts array must be constructed
 361    */
 362   lily_cookie_fprintf (out, "/sfnts [");
 363   t42_write_table (out, face, hbuf, hlength, false,
 364                    head_length, loca_length);
 365   delete[] hbuf;
 366
 367   idx = 0;
 368
 369   while (FT_Sfnt_Table_Info (face, idx, &tag, &length)
 370          != FT_Err_Table_Missing)
 371     {
 372       unsigned char *buf = new unsigned char[length];
 373       FT_Error error = FT_Load_Sfnt_Table (face, tag, 0, buf, NULL);
 374       if (error)
 375         programming_error ("FT_Load_Sfnt_Table (): error.");
 376
 377       if (tag == head_tag)
 378         {
 379           /* in the second pass simply store the computed font checksum */
 380           buf[8] = (font_checksum & 0xFF000000UL) >> 24;
 381           buf[9] = (font_checksum & 0x00FF0000UL) >> 16;
 382           buf[10] = (font_checksum & 0x0000FF00UL) >> 8;
 383           buf[11] = font_checksum & 0x000000FFUL;
 384         }
 385
 386       bool is_glyf_table = tag == glyf_tag && length > CHUNKSIZE;
 387       t42_write_table (out, face, buf, length, is_glyf_table,
 388                        head_length, loca_length);
 389
 390       delete[] buf;
 391       idx ++;
 392     }
 393   lily_cookie_fprintf (out, "\n] def\n");
 394 }
 395
 396 static void
 397 print_trailer (void *out,
 398                FT_Face face)
 399 {
 400   const int GLYPH_NAME_LEN = 256;
 401   char glyph_name[GLYPH_NAME_LEN];
 402
 403   TT_MaxProfile *mp
 404     = (TT_MaxProfile *)FT_Get_Sfnt_Table (face, ft_sfnt_maxp);
 405
 406   lily_cookie_fprintf (out, "/CharStrings %d dict dup begin\n", mp->numGlyphs);
 407
 408   Index_to_charcode_map ic_map (make_index_to_charcode_map (face));
 409
 410   int output_count = 0;
 411   for (int i = 0; i < mp->numGlyphs; i++)
 412     {
 413       glyph_name[0] = 0;
 414       if (face->face_flags & FT_FACE_FLAG_GLYPH_NAMES)
 415         {
 416           FT_Error error = FT_Get_Glyph_Name (face, i, glyph_name,
 417                                               GLYPH_NAME_LEN);
 418           if (error)
 419             {
 420               programming_error ("FT_Get_Glyph_Name (): error.");
 421               glyph_name[0] = 0;
 422             }
 423         }
 424
 425       if (!glyph_name[0] && ic_map.find (i) != ic_map.end ())
 426         {
 427           FT_ULong ucode = ic_map[i];
 428           get_unicode_name (glyph_name, ucode);
 429         }
 430
 431       if (i == 0)
 432         sprintf (glyph_name, ".notdef");
 433       else if (glyph_name == string (".notdef"))
 434         glyph_name[0] = '\0';
 435
 436       if (!glyph_name[0])
 437         get_glyph_index_name (glyph_name, i);
 438
 439       if (glyph_name[0])
 440         {
 441           lily_cookie_fprintf (out, "/%s %d def ", glyph_name, i);
 442           output_count ++;
 443         }
 444       else
 445         programming_error (to_string ("no name for glyph %d", i));
 446
 447       if (! (output_count % 5))
 448         lily_cookie_fprintf (out, "\n");
 449     }
 450
 451   lily_cookie_fprintf (out, "end readonly def\n");
 452   lily_cookie_fprintf (out, "FontName currentdict end definefont pop\n");
 453 }
 454
 455 static void
 456 create_type42_font (void *out, string name)
 457 {
 458   FT_Face face = open_ft_face (name);
 459
 460   print_header (out, face);
 461   print_body (out, face);
 462   print_trailer (out, face);
 463
 464   FT_Done_Face (face);
 465 }
 466
 467
 468 LY_DEFINE (ly_ttf_ps_name, "ly:ttf-ps-name",
 469            1, 0, 0, (SCM ttf_file_name),
 470            "Extract the PostScript name from a TrueType font.")
 471 {
 472   LY_ASSERT_TYPE (scm_is_string, ttf_file_name, 1);
 473   string file_name = ly_scm2string (ttf_file_name);
 474   if (be_verbose_global)
 475     progress_indication ("[" + file_name);
 476
 477   FT_Face face = open_ft_face (file_name);
 478   char const *ps_name_str0 = FT_Get_Postscript_Name (face);
 479   SCM ps_name = scm_from_locale_string (ps_name_str0 ? ps_name_str0 : "");
 480
 481   FT_Done_Face (face);
 482
 483   if (be_verbose_global)
 484     progress_indication ("]");
 485
 486   return ps_name;
 487 }
 488
 489
 490
 491 LY_DEFINE (ly_ttf_2_pfa, "ly:ttf->pfa",
 492            1, 0, 0, (SCM ttf_file_name),
 493            "Convert the contents of a TTF file to Type42 PFA, returning it as"
 494            " a string.")
 495 {
 496   LY_ASSERT_TYPE (scm_is_string, ttf_file_name, 1);
 497
 498   string file_name = ly_scm2string (ttf_file_name);
 499   if (be_verbose_global)
 500     progress_indication ("[" + file_name);
 501
 502   Memory_out_stream stream;
 503
 504   create_type42_font (&stream, file_name);
 505   SCM asscm = scm_from_locale_stringn (stream.get_string (),
 506                                        stream.get_length ());
 507
 508   if (be_verbose_global)
 509     progress_indication ("]");
 510
 511   return asscm;
 512 }