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, 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  cell=0;
  72         char autohinter=0;
  73         char seq=0;
  74         char alpha=0;
  75         char pack=0;
  76
  77         FT_Library freetype;
  78         FT_Face    face;
  79
  80         int  err;
  81         int  i;
  82
  83         char *out_fn="font.png";
  84
  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                         cell=strtol(optarg, NULL, 0);
 137                         break;
 138                 case 'o':
 139                         out_fn=optarg;
 140                         break;
 141                 case 'a':
 142                         autohinter=1;
 143                         break;
 144                 case 't':
 145                         alpha=1;
 146                         break;
 147                 case 'v':
 148                         ++verbose;
 149                         break;
 150                 case 'h':
 151                 case '?':
 152                         usage();
 153                         return 0;
 154                 case 'e':
 155                         seq=1;
 156                         break;
 157                 case 'd':
 158                         def_fn=optarg;
 159                         break;
 160                 case 'p':
 161                         pack=1;
 162                         break;
 163                 }
 164         }
 165         if(!strcmp(out_fn, "-"))
 166                 verbose=0;
 167
 168         if(optind!=argc-1)
 169         {
 170                 usage();
 171                 return 1;
 172         }
 173
 174         fn=argv[optind];
 175
 176         err=FT_Init_FreeType(&freetype);
 177         if(err)
 178         {
 179                 fprintf(stderr, "Couldn't initialize FreeType library\n");
 180                 return 1;
 181         }
 182
 183         err=FT_New_Face(freetype, fn, 0, &face);
 184         if(err)
 185         {
 186                 fprintf(stderr, "Couldn't load font file\n");
 187                 if(err==FT_Err_Unknown_File_Format)
 188                         fprintf(stderr, "Unknown file format\n");
 189                 return 1;
 190         }
 191
 192         if(verbose)
 193         {
 194                 const char *name=FT_Get_Postscript_Name(face);
 195                 printf("Font name: %s\n", name);
 196                 printf("Glyphs:    %ld\n", face->num_glyphs);
 197         }
 198
 199         err=FT_Set_Pixel_Sizes(face, 0, size);
 200         if(err)
 201         {
 202                 fprintf(stderr, "Couldn't set size\n");
 203                 return 1;
 204         }
 205
 206         font.size=size;
 207         init_font(&font, face, begin, end, autohinter);
 208         if(pack)
 209                 render_packed(&font);
 210         else
 211                 render_grid(&font, cell, cpl, seq);
 212         save_png(out_fn, &font.image, alpha);
 213         if(def_fn)
 214                 save_defs(def_fn, &font);
 215
 216         for(i=0; i<font.n_glyphs; ++i)
 217                 free(font.glyphs[i].image.data);
 218         free(font.glyphs);
 219         free(font.image.data);
 220
 221         FT_Done_Face(face);
 222         FT_Done_FreeType(freetype);
 223
 224         return 0;
 225 }
 226
 227 unsigned round_to_pot(unsigned n)
 228 {
 229         n-=1;
 230         n|=n>>1;
 231         n|=n>>2;
 232         n|=n>>4;
 233         n|=n>>8;
 234         n|=n>>16;
 235
 236         return n+1;
 237 }
 238
 239 void usage()
 240 {
 241         printf("ttf2png - True Type Font to PNG converter\n"
 242                 "Copyright (c) 2004-2008  Mikko Rasa, Mikkosoft Productions\n"
 243                 "Distributed under the GNU General Public License\n\n"
 244                 "Usage: ttf2png [options] <TTF file>\n\n"
 245                 "Accepted options (default values in [brackets])\n"
 246                 "  -r  Range of characters to convert in the format low,high [0,255]\n"
 247                 "  -s  Font size to use, in pixels [10]\n"
 248                 "  -l  Number of characters to put in one line [auto]\n"
 249                 "  -c  Character cell size, in pixels [auto]\n"
 250                 "  -o  Output file name (or - for stdout) [font.png]\n"
 251                 "  -a  Force autohinter\n"
 252                 "  -t  Render font to alpha channel\n"
 253                 "  -v  Increase the level of verbosity\n"
 254                 "  -e  Use cells in sequence, rather than by code\n"
 255                 "  -p  Pack the glyphs tightly instead of in a grid\n"
 256                 "  -d  Write a definition to the given file\n"
 257                 "  -h  Print this message\n");
 258 }
 259
 260 void init_font(Font *font, FT_Face face, unsigned first, unsigned last, int autohinter)
 261 {
 262         unsigned i;
 263         unsigned size=0;
 264
 265         font->ascent=(face->size->metrics.ascender+63)>>6;
 266         font->descent=(face->size->metrics.descender+63)>>6;
 267
 268         if(verbose>=1)
 269         {
 270                 printf("Ascent:    %d\n", font->ascent);
 271                 printf("Descent:   %d\n", font->descent);
 272         }
 273
 274         font->n_glyphs=0;
 275         font->glyphs=NULL;
 276         for(i=first; i<=last; ++i)
 277         {
 278                 unsigned  n;
 279                 FT_Bitmap *bmp=&face->glyph->bitmap;
 280                 int       x, y;
 281                 int       flags=0;
 282                 Glyph     *glyph;
 283
 284                 n=FT_Get_Char_Index(face, i);
 285                 if(!n) continue;
 286
 287                 if(autohinter)
 288                         flags|=FT_LOAD_FORCE_AUTOHINT;
 289                 FT_Load_Glyph(face, n, flags);
 290                 FT_Render_Glyph(face->glyph, FT_RENDER_MODE_NORMAL);
 291
 292                 if(verbose>=2)
 293                         printf("  Char %u: glyph %u, size %dx%d\n", i, n, bmp->width, bmp->rows);
 294
 295                 if(bmp->pixel_mode!=FT_PIXEL_MODE_GRAY)
 296                 {
 297                         fprintf(stderr, "Warning: Glyph %u skipped, not grayscale\n", n);
 298                         continue;
 299                 }
 300
 301                 if(font->n_glyphs>=size)
 302                 {
 303                         size+=16;
 304                         font->glyphs=(Glyph *)realloc(font->glyphs, size*sizeof(Glyph));
 305                 }
 306
 307                 glyph=&font->glyphs[font->n_glyphs++];
 308                 glyph->code=i;
 309                 glyph->image.w=bmp->width;
 310                 glyph->image.h=bmp->rows;
 311                 glyph->image.data=(char *)malloc(bmp->width*bmp->rows);
 312                 glyph->offset_x=face->glyph->bitmap_left;
 313                 glyph->offset_y=face->glyph->bitmap_top-bmp->rows;
 314                 glyph->advance=(int)(face->glyph->advance.x+32)/64;
 315
 316                 if(bmp->pitch<0)
 317                 {
 318                         for(y=0; y<bmp->rows; ++y) for(x=0; x<bmp->width; ++x)
 319                                 glyph->image.data[x+(glyph->image.h-1-y)*glyph->image.w]=bmp->buffer[x-y*bmp->pitch];
 320                 }
 321                 else
 322                 {
 323                         for(y=0; y<bmp->rows; ++y) for(x=0; x<bmp->width; ++x)
 324                                 glyph->image.data[x+y*glyph->image.w]=bmp->buffer[x+y*bmp->pitch];
 325                 }
 326         }
 327
 328         if(verbose>=1)
 329                 printf("Loaded %u glyphs\n", font->n_glyphs);
 330 }
 331
 332 void render_grid(Font *font, unsigned cell, unsigned cpl, int seq)
 333 {
 334         unsigned i;
 335         int      top=0, bot=0;
 336         unsigned first, last;
 337         unsigned maxw=0, maxh=0;
 338
 339         for(i=1;; i<<=1)
 340         {
 341                 first=font->glyphs[0].code&~(i-1);
 342                 last=first+i-1;
 343                 if(last>=font->glyphs[font->n_glyphs-1].code)
 344                         break;
 345         }
 346
 347         for(i=0; i<font->n_glyphs; ++i)
 348         {
 349                 int y;
 350
 351                 y=font->glyphs[i].offset_y+font->glyphs[i].image.h;
 352                 if(y>top)
 353                         top=y;
 354                 if(font->glyphs[i].offset_y<bot)
 355                         bot=font->glyphs[i].offset_y;
 356                 if(font->glyphs[i].image.w>maxw)
 357                         maxw=font->glyphs[i].image.w;
 358                 if(font->glyphs[i].image.h>maxh)
 359                         maxh=font->glyphs[i].image.h;
 360         }
 361
 362         if(cell==0)
 363         {
 364                 cell=top-bot;
 365                 if(maxw>cell)
 366                         cell=maxw;
 367         }
 368
 369         if(verbose>=1)
 370         {
 371                 printf("Max size:  %u x %u\n", maxw, maxh);
 372                 printf("Y range:   [%d %d]\n", bot, top);
 373                 if(maxw>cell || top-bot>cell)
 374                         fprintf(stderr,"Warning: character size exceeds cell size (%d)\n", cell);
 375         }
 376
 377         if(cpl==0)
 378         {
 379                 unsigned count=(seq ? font->n_glyphs : last-first+1);
 380                 for(i=1;; i<<=1)
 381                 {
 382                         cpl=i/cell;
 383                         if(cpl>0 && (count+cpl-1)/cpl<=cpl)
 384                                 break;
 385                 }
 386         }
 387
 388         font->image.w=round_to_pot(cpl*cell);
 389         if(seq && font->n_glyphs<last-first+1)
 390                 font->image.h=(font->n_glyphs+cpl-1)/cpl*cell;
 391         else
 392                 font->image.h=(last-first+cpl)/cpl*cell;
 393         font->image.h=round_to_pot(font->image.h);
 394
 395         font->image.data=(char *)malloc(font->image.w*font->image.h);
 396         memset(font->image.data, 255, font->image.w*font->image.h);
 397
 398         for(i=0; i<font->n_glyphs; ++i)
 399         {
 400                 Glyph    *glyph;
 401                 int      cx, cy;
 402                 unsigned x, y;
 403
 404                 glyph=&font->glyphs[i];
 405
 406                 if(seq)
 407                 {
 408                         cx=(i%cpl)*cell;
 409                         cy=(i/cpl)*cell;
 410                 }
 411                 else
 412                 {
 413                         cx=((glyph->code-first)%cpl)*cell;
 414                         cy=((glyph->code-first)/cpl)*cell;
 415                 }
 416
 417                 if(cell>glyph->image.w)
 418                         cx+=(cell-glyph->image.w)/2;
 419                 cy+=top-glyph->offset_y-glyph->image.h;
 420
 421                 glyph->x=cx;
 422                 glyph->y=cy;
 423
 424                 for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
 425                 {
 426                         if(cx+x<0 || cx+x>=font->image.w || cy+y<0 || cy+y>=font->image.h) continue;
 427                         font->image.data[cx+x+(cy+y)*font->image.w]=255-glyph->image.data[x+y*glyph->image.w];
 428                 }
 429         }
 430 }
 431
 432 void render_packed(Font *font)
 433 {
 434         unsigned i;
 435         unsigned area=0;
 436         unsigned last_h=0xFFFF;
 437         char     *used_glyphs;
 438         char     *used_pixels;
 439         unsigned cx=0, cy;
 440
 441         for(i=0; i<font->n_glyphs; ++i)
 442                 area+=(font->glyphs[i].image.w+1)*(font->glyphs[i].image.h+1);
 443
 444         for(font->image.w=1;; font->image.w<<=1)
 445         {
 446                 font->image.h=(area*5/4)/font->image.w;
 447                 if(font->image.h<=font->image.w)
 448                         break;
 449         }
 450         font->image.h=round_to_pot(font->image.h);
 451
 452         font->image.data=(char *)malloc(font->image.w*font->image.h);
 453         memset(font->image.data, 255, font->image.w*font->image.h);
 454         used_pixels=(char *)malloc(font->image.w*font->image.h);
 455         memset(used_pixels, 0, font->image.w*font->image.h);
 456         used_glyphs=(char *)malloc(font->n_glyphs);
 457         memset(used_glyphs, 0, font->n_glyphs);
 458
 459         for(cy=0; cy<font->image.h;)
 460         {
 461                 unsigned w;
 462                 unsigned x, y;
 463                 Glyph    *glyph=NULL;
 464                 unsigned best_score=0;
 465
 466                 for(; (cx<font->image.w && used_pixels[cx+cy*font->image.w]); ++cx);
 467                 if(cx>=font->image.w)
 468                 {
 469                         cx=0;
 470                         ++cy;
 471                         last_h=0xFFFF;
 472                         continue;
 473                 }
 474                 for(w=0; (cx+w<font->image.w && !used_pixels[cx+w+cy*font->image.w]); ++w);
 475
 476                 for(i=0; i<font->n_glyphs; ++i)
 477                 {
 478                         Glyph    *g;
 479
 480                         g=&font->glyphs[i];
 481                         if(!used_glyphs[i] && g->image.w<=w)
 482                         {
 483                                 unsigned score;
 484
 485                                 score=g->image.h+1;
 486                                 if(g->image.h==last_h)
 487                                         score*=g->image.w;
 488                                 else
 489                                         score+=g->image.w;
 490
 491                                 if(score>best_score)
 492                                 {
 493                                         glyph=g;
 494                                         best_score=score;
 495                                 }
 496                         }
 497                 }
 498
 499                 if(!glyph)
 500                 {
 501                         cx+=w;
 502                         continue;
 503                 }
 504
 505                 used_glyphs[glyph-font->glyphs]=1;
 506                 glyph->x=cx;
 507                 glyph->y=cy;
 508
 509                 for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
 510                 {
 511                         if(cx+x<0 || cx+x>=font->image.w || cy+y<0 || cy+y>=font->image.h) continue;
 512                         font->image.data[cx+x+(cy+y)*font->image.w]=255-glyph->image.data[x+y*glyph->image.w];
 513                 }
 514                 for(y=0; y<glyph->image.h+2; ++y) for(x=0; x<glyph->image.w+2; ++x)
 515                 {
 516                         if(cx+x<1 || cx+x>font->image.w || cy+y<1 || cy+y>font->image.h) continue;
 517                         used_pixels[cx+x-1+(cy+y-1)*font->image.w]=1;
 518                 }
 519
 520                 last_h=glyph->image.h;
 521         }
 522 }
 523
 524 int save_defs(const char *fn, const Font *font)
 525 {
 526         FILE     *out;
 527         unsigned i;
 528
 529         out=fopen(fn, "w");
 530         if(!out)
 531         {
 532                 fprintf(stderr, "Couldn't open %s\n",fn);
 533                 return -1;
 534         }
 535
 536         fprintf(out, "%d %d %d %d %d\n", font->image.w, font->image.h, font->size, font->ascent, font->descent);
 537         for(i=0; i<font->n_glyphs; ++i)
 538         {
 539                 const Glyph *g=&font->glyphs[i];
 540                 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);
 541         }
 542
 543         fclose(out);
 544
 545         return 0;
 546 }
 547
 548 int save_png(const char *fn, const Image *image, char alpha)
 549 {
 550         FILE       *out;
 551         png_struct *pngs;
 552         png_info   *pngi;
 553         png_byte   *rows[image->h];
 554         int        i;
 555         png_byte   *data2;
 556         int        color;
 557
 558         if(!strcmp(fn, "-"))
 559                 out=stdout;
 560         else
 561         {
 562                 out=fopen(fn, "wb");
 563                 if(!out)
 564                 {
 565                         fprintf(stderr, "Couldn't open %s\n",fn);
 566                         return -1;
 567                 }
 568         }
 569
 570         pngs=png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
 571         if(!pngs)
 572         {
 573                 fprintf(stderr, "Error writing PNG file\n");
 574                 return -1;
 575         }
 576         pngi=png_create_info_struct(pngs);
 577         if(!pngi)
 578         {
 579                 png_destroy_write_struct(&pngs, NULL);
 580                 fprintf(stderr, "Error writing PNG file\n");
 581                 return -1;
 582         }
 583
 584         png_init_io(pngs, out);
 585         if(alpha)
 586         {
 587                 data2=(png_byte *)malloc(image->w*image->h*2);
 588                 for(i=0; i<image->w*image->h; ++i)
 589                 {
 590                         data2[i*2]=255;
 591                         data2[i*2+1]=255-image->data[i];
 592                 }
 593                 for(i=0; i<image->h; ++i)
 594                         rows[i]=(png_byte *)(data2+i*image->w*2);
 595                 color=PNG_COLOR_TYPE_GRAY_ALPHA;
 596         }
 597         else
 598         {
 599                 for(i=0; i<image->h; ++i)
 600                         rows[i]=(png_byte *)(image->data+i*image->w);
 601                 color=PNG_COLOR_TYPE_GRAY;
 602         }
 603         png_set_IHDR(pngs, pngi, image->w, image->h, 8, color, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
 604         png_set_rows(pngs, pngi, rows);
 605         png_write_png(pngs, pngi, PNG_TRANSFORM_IDENTITY, NULL);
 606         png_destroy_write_struct(&pngs, &pngi);
 607         if(alpha)
 608                 free(data2);
 609
 610         if(verbose) printf("Saved %dx%d PNG image to %s\n", image->w, image->h, fn);
 611
 612         fclose(out);
 613
 614         return 0;
 615 }