ttf2png.c

   1 /*
   2 ttf2png - True Type Font to PNG converter
   3 Copyright (c) 2004-2008 Mikko Rasa
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 */
  19
  20 #include <stdio.h>
  21 #include <ctype.h>
  22 #include <unistd.h>
  23 #include <getopt.h>
  24 #include <png.h>
  25 #include <ft2build.h>
  26 #include FT_FREETYPE_H
  27
  28 typedef struct sImage
  29 {
  30         unsigned w, h;
  31         char     *data;
  32 } Image;
  33
  34 typedef struct sGlyph
  35 {
  36         unsigned code;
  37         Image    image;
  38         unsigned x, y;
  39         int      offset_x;
  40         int      offset_y;
  41         int      advance;
  42 } Glyph;
  43
  44 typedef struct sFont
  45 {
  46         unsigned size;
  47         int      ascent;
  48         int      descent;
  49         unsigned n_glyphs;
  50         Glyph    *glyphs;
  51         Image    image;
  52 } Font;
  53
  54 unsigned round_to_pot(unsigned);
  55 void usage();
  56 void init_font(Font *, FT_Face, unsigned, unsigned, int);
  57 void render_grid(Font *, unsigned, unsigned, unsigned, int);
  58 void render_packed(Font *);
  59 int save_defs(const char *, const Font *);
  60 int save_png(const char *, const Image *, char);
  61
  62 char verbose = 0;
  63
  64 int main(int argc, char **argv)
  65 {
  66         char *fn;
  67         int  begin = 0;
  68         int  end = 255;
  69         int  size = 10;
  70         int  cpl = 0;
  71         int  cellw = 0;
  72         int  cellh = 0;
  73         char autohinter = 0;
  74         char seq = 0;
  75         char alpha = 0;
  76         char pack = 0;
  77
  78         FT_Library freetype;
  79         FT_Face    face;
  80
  81         int  err;
  82         int  i;
  83
  84         char *out_fn = "font.png";
  85         char *def_fn = NULL;
  86
  87         Font font;
  88
  89         if(argc<2)
  90         {
  91                 usage();
  92                 return 1;
  93         }
  94
  95         while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:p")) != -1)
  96         {
  97                 char *ptr;
  98                 int  temp;
  99                 switch(i)
 100                 {
 101                 case 'r':
 102                         if(!strcmp(optarg, "all"))
 103                         {
 104                                 begin = 0;
 105                                 end = 0x110000;
 106                         }
 107                         else
 108                         {
 109                                 if(!isdigit(optarg[0]))
 110                                         temp = -1;
 111                                 else
 112                                 {
 113                                         temp = strtol(optarg, &ptr, 0);
 114                                         if(ptr[0]!=',' || !isdigit(ptr[1]))
 115                                                 temp = -1;
 116                                 }
 117                                 if(temp<0)
 118                                 {
 119                                         printf("Not a valid range: %s\n", optarg);
 120                                         exit(1);
 121                                 }
 122                                 else
 123                                 {
 124                                         begin = temp;
 125                                         end = strtol(ptr+1, NULL, 0);
 126                                 }
 127                         }
 128                         break;
 129                 case 's':
 130                         size = strtol(optarg, NULL, 0);
 131                         break;
 132                 case 'l':
 133                         cpl = strtol(optarg, NULL, 0);
 134                         break;
 135                 case 'c':
 136                         if(!strcmp(optarg, "auto"))
 137                         {
 138                                 cellw = 0;
 139                                 cellh = 0;
 140                         }
 141                         else if(!strcmp(optarg, "autorect"))
 142                         {
 143                                 cellw = 0;
 144                                 cellh = 1;
 145                         }
 146                         else
 147                         {
 148                                 cellw = strtol(optarg, &ptr, 0);
 149                                 if(ptr[0]=='x' && isdigit(ptr[1]))
 150                                         cellh = strtol(ptr+1, NULL, 0);
 151                         }
 152                         break;
 153                 case 'o':
 154                         out_fn = optarg;
 155                         break;
 156                 case 'a':
 157                         autohinter = 1;
 158                         break;
 159                 case 't':
 160                         alpha = 1;
 161                         break;
 162                 case 'v':
 163                         ++verbose;
 164                         break;
 165                 case 'h':
 166                 case '?':
 167                         usage();
 168                         return 0;
 169                 case 'e':
 170                         seq = 1;
 171                         break;
 172                 case 'd':
 173                         def_fn = optarg;
 174                         break;
 175                 case 'p':
 176                         pack = 1;
 177                         break;
 178                 }
 179         }
 180         if(!strcmp(out_fn, "-"))
 181                 verbose = 0;
 182
 183         if(optind!=argc-1)
 184         {
 185                 usage();
 186                 return 1;
 187         }
 188
 189         fn = argv[optind];
 190
 191         err = FT_Init_FreeType(&freetype);
 192         if(err)
 193         {
 194                 fprintf(stderr, "Couldn't initialize FreeType library\n");
 195                 return 1;
 196         }
 197
 198         err = FT_New_Face(freetype, fn, 0, &face);
 199         if(err)
 200         {
 201                 fprintf(stderr, "Couldn't load font file\n");
 202                 if(err==FT_Err_Unknown_File_Format)
 203                         fprintf(stderr, "Unknown file format\n");
 204                 return 1;
 205         }
 206
 207         if(verbose)
 208         {
 209                 const char *name = FT_Get_Postscript_Name(face);
 210                 printf("Font name: %s\n", name);
 211                 printf("Glyphs:    %ld\n", face->num_glyphs);
 212         }
 213
 214         err = FT_Set_Pixel_Sizes(face, 0, size);
 215         if(err)
 216         {
 217                 fprintf(stderr, "Couldn't set size\n");
 218                 return 1;
 219         }
 220
 221         font.size = size;
 222         init_font(&font, face, begin, end, autohinter);
 223         if(pack)
 224                 render_packed(&font);
 225         else
 226                 render_grid(&font, cellw, cellh, cpl, seq);
 227         save_png(out_fn, &font.image, alpha);
 228         if(def_fn)
 229                 save_defs(def_fn, &font);
 230
 231         for(i=0; i<font.n_glyphs; ++i)
 232                 free(font.glyphs[i].image.data);
 233         free(font.glyphs);
 234         free(font.image.data);
 235
 236         FT_Done_Face(face);
 237         FT_Done_FreeType(freetype);
 238
 239         return 0;
 240 }
 241
 242 unsigned round_to_pot(unsigned n)
 243 {
 244         n -= 1;
 245         n |= n>>1;
 246         n |= n>>2;
 247         n |= n>>4;
 248         n |= n>>8;
 249         n |= n>>16;
 250
 251         return n+1;
 252 }
 253
 254 void usage()
 255 {
 256         printf("ttf2png - True Type Font to PNG converter\n"
 257                 "Copyright (c) 2004-2008  Mikko Rasa, Mikkosoft Productions\n"
 258                 "Distributed under the GNU General Public License\n\n"
 259                 "Usage: ttf2png [options] <TTF file>\n\n"
 260                 "Accepted options (default values in [brackets])\n"
 261                 "  -r  Range of characters to convert in the format low,high [0,255]\n"
 262                 "  -s  Font size to use, in pixels [10]\n"
 263                 "  -l  Number of characters to put in one line [auto]\n"
 264                 "  -c  Character cell size, in pixels [auto]\n"
 265                 "  -o  Output file name (or - for stdout) [font.png]\n"
 266                 "  -a  Force autohinter\n"
 267                 "  -t  Render font to alpha channel\n"
 268                 "  -v  Increase the level of verbosity\n"
 269                 "  -e  Use cells in sequence, rather than by code\n"
 270                 "  -p  Pack the glyphs tightly instead of in a grid\n"
 271                 "  -d  Write a definition to the given file\n"
 272                 "  -h  Print this message\n");
 273 }
 274
 275 void init_font(Font *font, FT_Face face, unsigned first, unsigned last, int autohinter)
 276 {
 277         unsigned i;
 278         unsigned size = 0;
 279
 280         font->ascent = (face->size->metrics.ascender+63)>>6;
 281         font->descent = (face->size->metrics.descender+63)>>6;
 282
 283         if(verbose>=1)
 284         {
 285                 printf("Ascent:    %d\n", font->ascent);
 286                 printf("Descent:   %d\n", font->descent);
 287         }
 288
 289         font->n_glyphs = 0;
 290         font->glyphs = NULL;
 291         for(i=first; i<=last; ++i)
 292         {
 293                 unsigned  n;
 294                 FT_Bitmap *bmp = &face->glyph->bitmap;
 295                 int       x, y;
 296                 int       flags = 0;
 297                 Glyph     *glyph;
 298
 299                 n = FT_Get_Char_Index(face, i);
 300                 if(!n)
 301                         continue;
 302
 303                 if(autohinter)
 304                         flags |= FT_LOAD_FORCE_AUTOHINT;
 305                 FT_Load_Glyph(face, n, flags);
 306                 FT_Render_Glyph(face->glyph, FT_RENDER_MODE_NORMAL);
 307
 308                 if(verbose>=2)
 309                         printf("  Char %u: glyph %u, size %dx%d\n", i, n, bmp->width, bmp->rows);
 310
 311                 if(bmp->pixel_mode!=FT_PIXEL_MODE_GRAY)
 312                 {
 313                         fprintf(stderr, "Warning: Glyph %u skipped, not grayscale\n", n);
 314                         continue;
 315                 }
 316
 317                 if(font->n_glyphs>=size)
 318                 {
 319                         size += 16;
 320                         font->glyphs = (Glyph *)realloc(font->glyphs, size*sizeof(Glyph));
 321                 }
 322
 323                 glyph = &font->glyphs[font->n_glyphs++];
 324                 glyph->code = i;
 325                 glyph->image.w = bmp->width;
 326                 glyph->image.h = bmp->rows;
 327                 glyph->image.data = (char *)malloc(bmp->width*bmp->rows);
 328                 glyph->offset_x = face->glyph->bitmap_left;
 329                 glyph->offset_y = face->glyph->bitmap_top-bmp->rows;
 330                 glyph->advance = (int)(face->glyph->advance.x+32)/64;
 331
 332                 if(bmp->pitch<0)
 333                 {
 334                         for(y=0; y<bmp->rows; ++y) for(x=0; x<bmp->width; ++x)
 335                                 glyph->image.data[x+(glyph->image.h-1-y)*glyph->image.w] = bmp->buffer[x-y*bmp->pitch];
 336                 }
 337                 else
 338                 {
 339                         for(y=0; y<bmp->rows; ++y) for(x=0; x<bmp->width; ++x)
 340                                 glyph->image.data[x+y*glyph->image.w] = bmp->buffer[x+y*bmp->pitch];
 341                 }
 342         }
 343
 344         if(verbose>=1)
 345                 printf("Loaded %u glyphs\n", font->n_glyphs);
 346 }
 347
 348 void render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int seq)
 349 {
 350         unsigned i;
 351         int      top = 0, bot = 0;
 352         unsigned first, last;
 353         unsigned maxw = 0, maxh = 0;
 354
 355         for(i=1;; i<<=1)
 356         {
 357                 first = font->glyphs[0].code&~(i-1);
 358                 last = first+i-1;
 359                 if(last>=font->glyphs[font->n_glyphs-1].code)
 360                         break;
 361         }
 362
 363         for(i=0; i<font->n_glyphs; ++i)
 364         {
 365                 int y;
 366
 367                 y = font->glyphs[i].offset_y+font->glyphs[i].image.h;
 368                 if(y>top)
 369                         top = y;
 370                 if(font->glyphs[i].offset_y<bot)
 371                         bot = font->glyphs[i].offset_y;
 372                 if(font->glyphs[i].image.w>maxw)
 373                         maxw = font->glyphs[i].image.w;
 374                 if(font->glyphs[i].image.h>maxh)
 375                         maxh = font->glyphs[i].image.h;
 376         }
 377
 378         if(cellw==0)
 379         {
 380                 int square = (cellh==cellw);
 381                 cellw = maxw;
 382                 cellh = top-bot;
 383                 if(square)
 384                 {
 385                         if(cellh>cellw)
 386                                 cellw = cellh;
 387                         else
 388                                 cellh = cellw;
 389                 }
 390         }
 391
 392         if(verbose>=1)
 393         {
 394                 printf("Max size:  %u x %u\n", maxw, maxh);
 395                 printf("Y range:   [%d %d]\n", bot, top);
 396                 printf("Cell size: %u x %u\n", cellw, cellh);
 397                 if(maxw>cellw || top-bot>cellh)
 398                         fprintf(stderr, "Warning: character size exceeds cell size\n");
 399         }
 400
 401         if(cpl==0)
 402         {
 403                 unsigned count = (seq ? font->n_glyphs : last-first+1);
 404                 for(i=1;; i<<=1)
 405                 {
 406                         cpl = i/cellw;
 407                         if(cpl>0 && (count+cpl-1)/cpl*cellh<=cpl*cellw)
 408                                 break;
 409                 }
 410         }
 411
 412         font->image.w = round_to_pot(cpl*cellw);
 413         if(seq && font->n_glyphs<last-first+1)
 414                 font->image.h = (font->n_glyphs+cpl-1)/cpl*cellh;
 415         else
 416                 font->image.h = (last-first+cpl)/cpl*cellh;
 417         font->image.h = round_to_pot(font->image.h);
 418
 419         font->image.data = (char *)malloc(font->image.w*font->image.h);
 420         memset(font->image.data, 255, font->image.w*font->image.h);
 421
 422         for(i=0; i<font->n_glyphs; ++i)
 423         {
 424                 Glyph    *glyph;
 425                 int      ci, cx, cy;
 426                 unsigned x, y;
 427
 428                 glyph = &font->glyphs[i];
 429
 430                 if(seq)
 431                         ci = i;
 432                 else
 433                         ci = glyph->code-first;
 434
 435                 cx = (ci%cpl)*cellw;
 436                 cy = (ci/cpl)*cellh;
 437
 438                 if(cellw>glyph->image.w)
 439                         cx += (cellw-glyph->image.w)/2;
 440                 cy += top-glyph->offset_y-glyph->image.h;
 441
 442                 glyph->x = cx;
 443                 glyph->y = cy;
 444
 445                 for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
 446                 {
 447                         if(cx+x<0 || cx+x>=font->image.w || cy+y<0 || cy+y>=font->image.h)
 448                                 continue;
 449                         font->image.data[cx+x+(cy+y)*font->image.w] = 255-glyph->image.data[x+y*glyph->image.w];
 450                 }
 451         }
 452 }
 453
 454 void render_packed(Font *font)
 455 {
 456         unsigned i;
 457         unsigned area = 0;
 458         unsigned last_h = 0xFFFF;
 459         char     *used_glyphs;
 460         char     *used_pixels;
 461         unsigned cx = 0, cy;
 462
 463         for(i=0; i<font->n_glyphs; ++i)
 464                 area+=(font->glyphs[i].image.w+1)*(font->glyphs[i].image.h+1);
 465
 466         for(font->image.w=1;; font->image.w<<=1)
 467         {
 468                 font->image.h = (area*5/4)/font->image.w;
 469                 if(font->image.h<=font->image.w)
 470                         break;
 471         }
 472         font->image.h = round_to_pot(font->image.h);
 473
 474         font->image.data = (char *)malloc(font->image.w*font->image.h);
 475         memset(font->image.data, 255, font->image.w*font->image.h);
 476         used_pixels = (char *)malloc(font->image.w*font->image.h);
 477         memset(used_pixels, 0, font->image.w*font->image.h);
 478         used_glyphs = (char *)malloc(font->n_glyphs);
 479         memset(used_glyphs, 0, font->n_glyphs);
 480
 481         for(cy=0; cy<font->image.h;)
 482         {
 483                 unsigned w;
 484                 unsigned x, y;
 485                 Glyph    *glyph = NULL;
 486                 unsigned best_score = 0;
 487
 488                 for(; (cx<font->image.w && used_pixels[cx+cy*font->image.w]); ++cx) ;
 489                 if(cx>=font->image.w)
 490                 {
 491                         cx = 0;
 492                         ++cy;
 493                         last_h = 0xFFFF;
 494                         continue;
 495                 }
 496                 for(w=0; (cx+w<font->image.w && !used_pixels[cx+w+cy*font->image.w]); ++w) ;
 497
 498                 for(i=0; i<font->n_glyphs; ++i)
 499                 {
 500                         Glyph *g;
 501
 502                         g = &font->glyphs[i];
 503                         if(!used_glyphs[i] && g->image.w<=w)
 504                         {
 505                                 unsigned score;
 506
 507                                 score = g->image.h+1;
 508                                 if(g->image.h==last_h)
 509                                         score *= g->image.w;
 510                                 else
 511                                         score += g->image.w;
 512
 513                                 if(score>best_score)
 514                                 {
 515                                         glyph = g;
 516                                         best_score = score;
 517                                 }
 518                         }
 519                 }
 520
 521                 if(!glyph)
 522                 {
 523                         cx += w;
 524                         continue;
 525                 }
 526
 527                 used_glyphs[glyph-font->glyphs] = 1;
 528                 glyph->x = cx;
 529                 glyph->y = cy;
 530
 531                 for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
 532                 {
 533                         if(cx+x<0 || cx+x>=font->image.w || cy+y<0 || cy+y>=font->image.h)
 534                                 continue;
 535                         font->image.data[cx+x+(cy+y)*font->image.w] = 255-glyph->image.data[x+y*glyph->image.w];
 536                 }
 537                 for(y=0; y<glyph->image.h+2; ++y) for(x=0; x<glyph->image.w+2; ++x)
 538                 {
 539                         if(cx+x<1 || cx+x>font->image.w || cy+y<1 || cy+y>font->image.h)
 540                                 continue;
 541                         used_pixels[cx+x-1+(cy+y-1)*font->image.w] = 1;
 542                 }
 543
 544                 last_h = glyph->image.h;
 545         }
 546 }
 547
 548 int save_defs(const char *fn, const Font *font)
 549 {
 550         FILE     *out;
 551         unsigned i;
 552
 553         out = fopen(fn, "w");
 554         if(!out)
 555         {
 556                 fprintf(stderr, "Couldn't open %s\n",fn);
 557                 return -1;
 558         }
 559
 560         fprintf(out, "%d %d %d %d %d\n", font->image.w, font->image.h, font->size, font->ascent, font->descent);
 561         for(i=0; i<font->n_glyphs; ++i)
 562         {
 563                 const Glyph *g = &font->glyphs[i];
 564                 fprintf(out, "%u %u %u %u %u %d %d %d\n", g->code, g->x, g->y, g->image.w, g->image.h, g->offset_x, g->offset_y, g->advance);
 565         }
 566
 567         fclose(out);
 568
 569         return 0;
 570 }
 571
 572 int save_png(const char *fn, const Image *image, char alpha)
 573 {
 574         FILE       *out;
 575         png_struct *pngs;
 576         png_info   *pngi;
 577         png_byte   *rows[image->h];
 578         int        i;
 579         png_byte   *data2;
 580         int        color;
 581
 582         if(!strcmp(fn, "-"))
 583                 out = stdout;
 584         else
 585         {
 586                 out = fopen(fn, "wb");
 587                 if(!out)
 588                 {
 589                         fprintf(stderr, "Couldn't open %s\n",fn);
 590                         return -1;
 591                 }
 592         }
 593
 594         pngs = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
 595         if(!pngs)
 596         {
 597                 fprintf(stderr, "Error writing PNG file\n");
 598                 return -1;
 599         }
 600         pngi = png_create_info_struct(pngs);
 601         if(!pngi)
 602         {
 603                 png_destroy_write_struct(&pngs, NULL);
 604                 fprintf(stderr, "Error writing PNG file\n");
 605                 return -1;
 606         }
 607
 608         png_init_io(pngs, out);
 609         if(alpha)
 610         {
 611                 data2 = (png_byte *)malloc(image->w*image->h*2);
 612                 for(i=0; i<image->w*image->h; ++i)
 613                 {
 614                         data2[i*2] = 255;
 615                         data2[i*2+1] = 255-image->data[i];
 616                 }
 617                 for(i=0; i<image->h; ++i)
 618                         rows[i] = (png_byte *)(data2+i*image->w*2);
 619                 color = PNG_COLOR_TYPE_GRAY_ALPHA;
 620         }
 621         else
 622         {
 623                 for(i=0; i<image->h; ++i)
 624                         rows[i] = (png_byte *)(image->data+i*image->w);
 625                 color = PNG_COLOR_TYPE_GRAY;
 626         }
 627         png_set_IHDR(pngs, pngi, image->w, image->h, 8, color, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
 628         png_set_rows(pngs, pngi, rows);
 629         png_write_png(pngs, pngi, PNG_TRANSFORM_IDENTITY, NULL);
 630         png_destroy_write_struct(&pngs, &pngi);
 631         if(alpha)
 632                 free(data2);
 633
 634         if(verbose)
 635                 printf("Saved %dx%d PNG image to %s\n", image->w, image->h, fn);
 636
 637         fclose(out);
 638
 639         return 0;
 640 }