font.c

   1 /* font handling */
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include "roff.h"
   6
   7 /* convert wid in device unitwidth size to size sz */
   8 #define DEVWID(sz, wid)         (((wid) * (sz) + (dev_uwid / 2)) / dev_uwid)
   9
  10 /* flags for gpat->flg */
  11 #define GF_PAT          1       /* gsub/gpos pattern glyph */
  12 #define GF_REP          2       /* gsub replacement glyph */
  13 #define GF_CON          4       /* context glyph */
  14 #define GF_GRP          8       /* glyph group */
  15
  16 /* glyph substitution and positioning rules */
  17 struct grule {
  18         struct gpat {                   /* rule description */
  19                 short g;                /* glyph index */
  20                 short flg;              /* pattern flags; GF_* */
  21                 short x, y, xadv, yadv; /* gpos data */
  22         } *pats;                        /* rule pattern */
  23         short len;                      /* pats[] length */
  24         short feat, scrp;               /* rule's feature and script */
  25 };
  26
  27 struct font {
  28         char name[FNLEN];
  29         char fontname[FNLEN];
  30         int spacewid;
  31         int special;
  32         int cs, cs_ps, bd, zoom;        /* for .cs, .bd, .fzoom requests */
  33         int s1, n1, s2, n2;             /* for .tkf request */
  34         struct glyph *gl;               /* glyphs present in the font */
  35         int gl_n, gl_sz;                /* number of glyphs in the font */
  36         struct dict *gl_dict;           /* mapping from gl[i].id to i */
  37         struct dict *ch_dict;           /* charset mapping */
  38         struct dict *ch_map;            /* characters mapped via font_map() */
  39         /* font features and scripts */
  40         char feat_name[NFEATS][8];      /* feature names */
  41         int feat_set[NFEATS];           /* feature enabled */
  42         char scrp_name[NSCRPS][8];      /* script names */
  43         int scrp;                       /* current script */
  44         /* glyph substitution and positioning */
  45         struct grule *gsub;             /* glyph substitution rules */
  46         int gsub_n, gsub_sz;
  47         struct grule *gpos;             /* glyph positioning rules */
  48         int gpos_n, gpos_sz;
  49         struct iset *gsub0;             /* rules matching a glyph at pos 0 */
  50         struct iset *gpos0;             /* rules matching a glyph at pos 0 */
  51         struct iset *ggrp;              /* glyph groups */
  52 };
  53
  54 /* find a glyph by its name */
  55 struct glyph *font_find(struct font *fn, char *name)
  56 {
  57         int i = dict_get(fn->ch_map, name);
  58         if (i == -1)            /* -2 means the glyph has been unmapped */
  59                 i = dict_get(fn->ch_dict, name);
  60         return i >= 0 ? fn->gl + i : NULL;
  61 }
  62
  63 /* find a glyph by its device-dependent identifier */
  64 struct glyph *font_glyph(struct font *fn, char *id)
  65 {
  66         int i = dict_get(fn->gl_dict, id);
  67         return i >= 0 ? &fn->gl[i] : NULL;
  68 }
  69
  70 static int font_glyphput(struct font *fn, char *id, char *name, int type)
  71 {
  72         struct glyph *g;
  73         if (fn->gl_n == fn->gl_sz) {
  74                 fn->gl_sz = fn->gl_sz + 1024;
  75                 fn->gl = mextend(fn->gl, fn->gl_n, fn->gl_sz, sizeof(fn->gl[0]));
  76         }
  77         g = &fn->gl[fn->gl_n];
  78         snprintf(g->id, sizeof(g->id), "%s", id);
  79         snprintf(g->name, sizeof(g->name), "%s", name);
  80         g->type = type;
  81         g->font = fn;
  82         dict_put(fn->gl_dict, g->id, fn->gl_n);
  83         return fn->gl_n++;
  84 }
  85
  86 /* map character name to the given glyph; remove the mapping if id is NULL */
  87 int font_map(struct font *fn, char *name, char *id)
  88 {
  89         int gidx = -1;
  90         if (id)
  91                 gidx = font_glyph(fn, id) ? font_glyph(fn, id) - fn->gl : -2;
  92         dict_put(fn->ch_map, name, gidx);
  93         return 0;
  94 }
  95
  96 /* return nonzero if character name has been mapped with font_map() */
  97 int font_mapped(struct font *fn, char *name)
  98 {
  99         return dict_get(fn->ch_map, name) != -1;
 100 }
 101
 102 /* enable/disable ligatures; first bit for liga and the second bit for rlig */
 103 static int font_featlg(struct font *fn, int val)
 104 {
 105         int ret = 0;
 106         ret |= font_feat(fn, "liga", val & 1);
 107         ret |= font_feat(fn, "rlig", val & 2) << 1;
 108         return ret;
 109 }
 110
 111 /* enable/disable pairwise kerning */
 112 static int font_featkn(struct font *fn, int val)
 113 {
 114         return font_feat(fn, "kern", val);
 115 }
 116
 117 /* glyph index in fn->glyphs[] */
 118 static int font_idx(struct font *fn, struct glyph *g)
 119 {
 120         return g ? g - fn->gl : -1;
 121 }
 122
 123 static int font_gpatmatch(struct font *fn, struct gpat *p, int g)
 124 {
 125         int *r;
 126         if (!(p->flg & GF_GRP))
 127                 return p->g == g;
 128         r = iset_get(fn->ggrp, p->g);
 129         while (r && *r >= 0)
 130                 if (*r++ == g)
 131                         return 1;
 132         return 0;
 133 }
 134
 135 static int font_rulematch(struct font *fn, struct grule *rule,
 136                         int *src, int slen, int *dst, int dlen)
 137 {
 138         int sidx = 0;           /* the index of matched glyphs in src */
 139         int ncon = 0;           /* number of initial context glyphs */
 140         struct gpat *pats = rule->pats;
 141         int j;
 142         if (fn->scrp >= 0 && fn->scrp != rule->scrp)
 143                 return 0;
 144         if (!fn->feat_set[rule->feat])
 145                 return 0;
 146         /* the number of initial context glyphs */
 147         for (j = 0; j < rule->len && pats[j].flg & GF_CON; j++)
 148                 ncon++;
 149         if (dlen < ncon)
 150                 return 0;
 151         /* matching the base pattern */
 152         for (; j < rule->len; j++) {
 153                 if (pats[j].flg & GF_REP)
 154                         continue;
 155                 if (sidx >= slen || !font_gpatmatch(fn, &pats[j], src[sidx]))
 156                         return 0;
 157                 sidx++;
 158         }
 159         /* matching the initial context */
 160         for (j = 0; j < rule->len && pats[j].flg & GF_CON; j++)
 161                 if (!font_gpatmatch(fn, &pats[j], dst[j - ncon]))
 162                         return 0;
 163         return 1;
 164 }
 165
 166 /* find a matching gsub/gpos rule; *idx should be -1 initially */
 167 static int font_findrule(struct font *fn, int gsub, int pos,
 168                 int *fwd, int fwdlen, int *ctx, int ctxlen, int *idx)
 169 {
 170         struct grule *rules = gsub ? fn->gsub : fn->gpos;
 171         int *r1 = iset_get(gsub ? fn->gsub0 : fn->gpos0, fwd[0]);
 172         while (r1 && r1[++*idx] >= 0) {
 173                 if (r1[*idx] >= pos && font_rulematch(fn, &rules[r1[*idx]],
 174                                                 fwd, fwdlen, ctx, ctxlen))
 175                         return r1[*idx];
 176         }
 177         return -1;
 178 }
 179
 180 /* perform all possible gpos rules on src */
 181 static void font_performgpos(struct font *fn, int *src, int slen,
 182                 int *x, int *y, int *xadv, int *yadv)
 183 {
 184         struct grule *gpos = fn->gpos;
 185         struct gpat *pats;
 186         int i, k;
 187         for (i = 0; i < slen; i++) {
 188                 int idx = -1;
 189                 while (1) {
 190                         int r = font_findrule(fn, 0, 0, src + i, slen - i,
 191                                                 src + i, i, &idx);
 192                         if (r < 0)
 193                                 break;
 194                         pats = gpos[r].pats;
 195                         /* we should accumulate the values... */
 196                         for (k = 0; k < gpos[r].len; k++) {
 197                                 x[i + k] += pats[k].x;
 198                                 y[i + k] += pats[k].y;
 199                                 xadv[i + k] += pats[k].xadv;
 200                                 yadv[i + k] += pats[k].yadv;
 201                         }
 202                 }
 203         }
 204 }
 205
 206 /* find the first gsub rule after pos that matches any glyph in src */
 207 static int font_firstgsub(struct font *fn, int pos, int *src, int slen)
 208 {
 209         int best = -1;
 210         int i;
 211         for (i = 0; i < slen; i++) {
 212                 int idx = -1;
 213                 int r = font_findrule(fn, 1, pos, src + i, slen - i,
 214                                         src + i, i, &idx);
 215                 if (r >= 0 && (best < 0 || r < best))
 216                         best = r;
 217         }
 218         return best;
 219 }
 220
 221 /* apply the given gsub rule to all matches in src */
 222 static int font_gsubapply(struct font *fn, struct grule *rule,
 223                         int *src, int slen, int *smap)
 224 {
 225         int dst[WORDLEN];
 226         int dlen = 0;
 227         int dmap[WORDLEN];
 228         int i, j;
 229         memset(dmap, 0, slen * sizeof(dmap[i]));
 230         for (i = 0; i < slen; i++) {
 231                 dmap[dlen] = smap[i];
 232                 if (font_rulematch(fn, rule, src + i, slen - i,
 233                                         dst + dlen, dlen)) {
 234                         for (j = 0; j < rule->len; j++) {
 235                                 if (rule->pats[j].flg & GF_REP)
 236                                         dst[dlen++] = rule->pats[j].g;
 237                                 if (rule->pats[j].flg & GF_PAT)
 238                                         i++;
 239                         }
 240                         i--;
 241                 } else {
 242                         dst[dlen++] = src[i];
 243                 }
 244         }
 245         memcpy(src, dst, dlen * sizeof(dst[0]));
 246         memcpy(smap, dmap, dlen * sizeof(dmap[0]));
 247         return dlen;
 248 }
 249
 250 /* perform all possible gsub rules on src */
 251 static int font_performgsub(struct font *fn, int *src, int slen, int *smap)
 252 {
 253         int i = -1;
 254         while (++i >= 0) {
 255                 if ((i = font_firstgsub(fn, i, src, slen)) < 0)
 256                         break;
 257                 slen = font_gsubapply(fn, &fn->gsub[i], src, slen, smap);
 258         }
 259         return slen;
 260 }
 261
 262 int font_layout(struct font *fn, struct glyph **gsrc, int nsrc, int sz,
 263                 struct glyph **gdst, int *dmap,
 264                 int *x, int *y, int *xadv, int *yadv, int lg, int kn)
 265 {
 266         int dst[WORDLEN];
 267         int ndst = nsrc;
 268         int i;
 269         int featlg, featkn;
 270         /* initialising dst */
 271         for (i = 0; i < nsrc; i++)
 272                 dst[i] = font_idx(fn, gsrc[i]);
 273         for (i = 0; i < ndst; i++)
 274                 dmap[i] = i;
 275         memset(x, 0, ndst * sizeof(x[0]));
 276         memset(y, 0, ndst * sizeof(y[0]));
 277         memset(xadv, 0, ndst * sizeof(xadv[0]));
 278         memset(yadv, 0, ndst * sizeof(yadv[0]));
 279         /* substitution rules */
 280         if (lg)
 281                 featlg = font_featlg(fn, 3);
 282         ndst = font_performgsub(fn, dst, ndst, dmap);
 283         if (lg)
 284                 font_featlg(fn, featlg);
 285         /* positioning rules */
 286         if (kn)
 287                 featkn = font_featkn(fn, 1);
 288         font_performgpos(fn, dst, ndst, x, y, xadv, yadv);
 289         if (kn)
 290                 font_featkn(fn, featkn);
 291         for (i = 0; i < ndst; i++)
 292                 gdst[i] = fn->gl + dst[i];
 293         return ndst;
 294 }
 295
 296 static int font_readchar(struct font *fn, FILE *fin, int *n, int *gid)
 297 {
 298         struct glyph *g;
 299         char tok[ILNLEN];
 300         char name[ILNLEN];
 301         char id[ILNLEN];
 302         int type;
 303         if (fscanf(fin, "%s %s", name, tok) != 2)
 304                 return 1;
 305         if (!strcmp("---", name))
 306                 sprintf(name, "c%04d", *n);
 307         if (strcmp("\"", tok)) {
 308                 if (fscanf(fin, "%d %s", &type, id) != 2)
 309                         return 1;
 310                 *gid = dict_get(fn->gl_dict, id);
 311                 if (*gid < 0) {
 312                         *gid = font_glyphput(fn, id, name, type);
 313                         g = &fn->gl[*gid];
 314                         sscanf(tok, "%hd,%hd,%hd,%hd,%hd", &g->wid,
 315                                 &g->llx, &g->lly, &g->urx, &g->ury);
 316                 }
 317                 dict_put(fn->ch_dict, name, *gid);
 318                 (*n)++;
 319         } else {
 320                 dict_put(fn->ch_map, name, *gid);
 321         }
 322         return 0;
 323 }
 324
 325 static int font_findfeat(struct font *fn, char *feat)
 326 {
 327         int i;
 328         for (i = 0; i < LEN(fn->feat_name) && fn->feat_name[i][0]; i++)
 329                 if (!strcmp(feat, fn->feat_name[i]))
 330                         return i;
 331         if (i < LEN(fn->feat_name)) {
 332                 snprintf(fn->feat_name[i], sizeof(fn->feat_name[i]), "%s", feat);
 333                 return i;
 334         }
 335         return -1;
 336 }
 337
 338 static int font_findscrp(struct font *fn, char *scrp)
 339 {
 340         int i;
 341         for (i = 0; i < LEN(fn->scrp_name) && fn->scrp_name[i][0]; i++)
 342                 if (!strcmp(scrp, fn->scrp_name[i]))
 343                         return i;
 344         if (i < LEN(fn->scrp_name)) {
 345                 snprintf(fn->scrp_name[i], sizeof(fn->scrp_name[i]), "%s", scrp);
 346                 return i;
 347         }
 348         return -1;
 349 }
 350
 351 static struct gpat *font_gpat(struct font *fn, int len)
 352 {
 353         struct gpat *pats = xmalloc(len * sizeof(pats[0]));
 354         memset(pats, 0, len * sizeof(pats[0]));
 355         return pats;
 356 }
 357
 358 static struct grule *font_gsub(struct font *fn, int len, int feat, int scrp)
 359 {
 360         struct grule *rule;
 361         struct gpat *pats = font_gpat(fn, len);
 362         if (fn->gsub_n  == fn->gsub_sz) {
 363                 fn->gsub_sz = fn->gsub_sz + 1024;
 364                 fn->gsub = mextend(fn->gsub, fn->gsub_n, fn->gsub_sz,
 365                                 sizeof(fn->gsub[0]));
 366         }
 367         rule = &fn->gsub[fn->gsub_n++];
 368         rule->pats = pats;
 369         rule->len = len;
 370         rule->feat = feat;
 371         rule->scrp = scrp;
 372         return rule;
 373 }
 374
 375 static struct grule *font_gpos(struct font *fn, int len, int feat, int scrp)
 376 {
 377         struct grule *rule;
 378         struct gpat *pats = font_gpat(fn, len);
 379         if (fn->gpos_n == fn->gpos_sz) {
 380                 fn->gpos_sz = fn->gpos_sz + 1024;
 381                 fn->gpos = mextend(fn->gpos, fn->gpos_n, fn->gpos_sz,
 382                                 sizeof(fn->gpos[0]));
 383         }
 384         rule = &fn->gpos[fn->gpos_n++];
 385         rule->pats = pats;
 386         rule->len = len;
 387         rule->feat = feat;
 388         rule->scrp = scrp;
 389         return rule;
 390 }
 391
 392 static int font_readgpat(struct font *fn, struct gpat *p, char *s)
 393 {
 394         if (s[0] == '@') {
 395                 p->g = atoi(s + 1);
 396                 if (iset_len(fn->ggrp, p->g) == 1)
 397                         p->g = iset_get(fn->ggrp, p->g)[0];
 398                 else
 399                         p->flg |= GF_GRP;
 400         } else {
 401                 p->g = font_idx(fn, font_glyph(fn, s));
 402         }
 403         return p->g < 0;
 404 }
 405
 406 static void font_readfeat(struct font *fn, char *tok, int *feat, int *scrp)
 407 {
 408         *scrp = -1;
 409         if (strchr(tok, ':')) {         /* "feature:script" */
 410                 *scrp = font_findscrp(fn, strchr(tok, ':') + 1);
 411                 strchr(tok, ':')[0] = '\0';
 412         }
 413         *feat = font_findfeat(fn, tok);
 414 }
 415
 416 static int font_readgsub(struct font *fn, FILE *fin)
 417 {
 418         char tok[128];
 419         struct grule *rule;
 420         int feat, scrp;
 421         int i, n;
 422         if (fscanf(fin, "%s %d", tok, &n) != 2)
 423                 return 1;
 424         font_readfeat(fn, tok, &feat, &scrp);
 425         rule = font_gsub(fn, n, feat, scrp);
 426         for (i = 0; i < n; i++) {
 427                 if (fscanf(fin, "%s", tok) != 1)
 428                         return 1;
 429                 if (tok[0] == '-')
 430                         rule->pats[i].flg = GF_PAT;
 431                 if (tok[0] == '=')
 432                         rule->pats[i].flg = GF_CON;
 433                 if (tok[0] == '+')
 434                         rule->pats[i].flg = GF_REP;
 435                 if (!tok[0] || font_readgpat(fn, &rule->pats[i], tok + 1))
 436                         return 0;
 437         }
 438         return 0;
 439 }
 440
 441 static int font_readgpos(struct font *fn, FILE *fin)
 442 {
 443         char tok[128];
 444         char *col;
 445         struct grule *rule;
 446         int feat, scrp;
 447         int i, n;
 448         if (fscanf(fin, "%s %d", tok, &n) != 2)
 449                 return 1;
 450         font_readfeat(fn, tok, &feat, &scrp);
 451         rule = font_gpos(fn, n, feat, scrp);
 452         for (i = 0; i < n; i++) {
 453                 if (fscanf(fin, "%s", tok) != 1)
 454                         return 1;
 455                 col = strchr(tok, ':');
 456                 if (col)
 457                         *col = '\0';
 458                 rule->pats[i].flg = GF_PAT;
 459                 if (!tok[0] || font_readgpat(fn, &rule->pats[i], tok))
 460                         return 0;
 461                 if (col)
 462                         sscanf(col + 1, "%hd%hd%hd%hd",
 463                                 &rule->pats[i].x, &rule->pats[i].y,
 464                                 &rule->pats[i].xadv, &rule->pats[i].yadv);
 465         }
 466         return 0;
 467 }
 468
 469 static int font_readggrp(struct font *fn, FILE *fin)
 470 {
 471         char tok[ILNLEN];
 472         int id, n, i, g;
 473         if (fscanf(fin, "%d %d", &id, &n) != 2)
 474                 return 1;
 475         for (i = 0; i < n; i++) {
 476                 if (fscanf(fin, "%s", tok) != 1)
 477                         return 1;
 478                 g = font_idx(fn, font_glyph(fn, tok));
 479                 if (g >= 0)
 480                         iset_put(fn->ggrp, id, g);
 481         }
 482         return 0;
 483 }
 484
 485 static int font_readkern(struct font *fn, FILE *fin)
 486 {
 487         char c1[ILNLEN], c2[ILNLEN];
 488         struct grule *rule;
 489         int val;
 490         if (fscanf(fin, "%s %s %d", c1, c2, &val) != 3)
 491                 return 1;
 492         rule = font_gpos(fn, 2, font_findfeat(fn, "kern"), -1);
 493         rule->pats[0].g = font_idx(fn, font_glyph(fn, c1));
 494         rule->pats[1].g = font_idx(fn, font_glyph(fn, c2));
 495         rule->pats[0].xadv = val;
 496         rule->pats[0].flg = GF_PAT;
 497         rule->pats[1].flg = GF_PAT;
 498         return 0;
 499 }
 500
 501 static void font_lig(struct font *fn, char *lig)
 502 {
 503         char c[GNLEN];
 504         int g[WORDLEN];
 505         struct grule *rule;
 506         char *s = lig;
 507         int j, n = 0;
 508         while (utf8read(&s, c) > 0)
 509                 g[n++] = font_idx(fn, font_find(fn, c));
 510         rule = font_gsub(fn, n + 1, font_findfeat(fn, "liga"), -1);
 511         for (j = 0; j < n; j++) {
 512                 rule->pats[j].g = g[j];
 513                 rule->pats[j].flg = GF_PAT;
 514         }
 515         rule->pats[n].g = font_idx(fn, font_find(fn, lig));
 516         rule->pats[n].flg = GF_REP;
 517 }
 518
 519 static void skipline(FILE* filp)
 520 {
 521         int c;
 522         do {
 523                 c = getc(filp);
 524         } while (c != '\n' && c != EOF);
 525 }
 526
 527 static struct gpat *font_rulefirstpat(struct font *fn, struct grule *rule)
 528 {
 529         int i;
 530         for (i = 0; i < rule->len; i++)
 531                 if (!(rule->pats[i].flg & (GF_REP | GF_CON)))
 532                         return &rule->pats[i];
 533         return NULL;
 534 }
 535
 536 static void font_isetinsert(struct font *fn, struct iset *iset, int rule, struct gpat *p)
 537 {
 538         if (p->flg & GF_GRP) {
 539                 int *r = iset_get(fn->ggrp, p->g);
 540                 while (r && *r >= 0)
 541                         iset_put(iset, *r++, rule);
 542         } else {
 543                 if (p->g >= 0)
 544                         iset_put(iset, p->g, rule);
 545         }
 546 }
 547
 548 struct font *font_open(char *path)
 549 {
 550         struct font *fn;
 551         int ch_g = -1;          /* last glyph in the charset */
 552         int ch_n = 0;                   /* number of glyphs in the charset */
 553         char tok[ILNLEN];
 554         FILE *fin;
 555         char ligs[512][GNLEN];
 556         int ligs_n = 0;
 557         int i;
 558         fin = fopen(path, "r");
 559         if (!fin)
 560                 return NULL;
 561         fn = xmalloc(sizeof(*fn));
 562         if (!fn) {
 563                 fclose(fin);
 564                 return NULL;
 565         }
 566         memset(fn, 0, sizeof(*fn));
 567         fn->gl_dict = dict_make(-1, 1, 0);
 568         fn->ch_dict = dict_make(-1, 1, 0);
 569         fn->ch_map = dict_make(-1, 1, 0);
 570         fn->ggrp = iset_make();
 571         while (fscanf(fin, "%s", tok) == 1) {
 572                 if (!strcmp("char", tok)) {
 573                         font_readchar(fn, fin, &ch_n, &ch_g);
 574                 } else if (!strcmp("kern", tok)) {
 575                         font_readkern(fn, fin);
 576                 } else if (!strcmp("ligatures", tok)) {
 577                         while (fscanf(fin, "%s", ligs[ligs_n]) == 1) {
 578                                 if (!strcmp("0", ligs[ligs_n]))
 579                                         break;
 580                                 if (ligs_n < LEN(ligs))
 581                                         ligs_n++;
 582                         }
 583                 } else if (!strcmp("gsub", tok)) {
 584                         font_readgsub(fn, fin);
 585                 } else if (!strcmp("gpos", tok)) {
 586                         font_readgpos(fn, fin);
 587                 } else if (!strcmp("ggrp", tok)) {
 588                         font_readggrp(fn, fin);
 589                 } else if (!strcmp("spacewidth", tok)) {
 590                         fscanf(fin, "%d", &fn->spacewid);
 591                 } else if (!strcmp("special", tok)) {
 592                         fn->special = 1;
 593                 } else if (!strcmp("name", tok)) {
 594                         fscanf(fin, "%s", fn->name);
 595                 } else if (!strcmp("fontname", tok)) {
 596                         fscanf(fin, "%s", fn->fontname);
 597                 } else if (!strcmp("charset", tok)) {
 598                         while (!font_readchar(fn, fin, &ch_n, &ch_g))
 599                                 ;
 600                         break;
 601                 }
 602                 skipline(fin);
 603         }
 604         for (i = 0; i < ligs_n; i++)
 605                 font_lig(fn, ligs[i]);
 606         fclose(fin);
 607         fn->gsub0 = iset_make();
 608         fn->gpos0 = iset_make();
 609         for (i = 0; i < fn->gsub_n; i++)
 610                 font_isetinsert(fn, fn->gsub0, i,
 611                         font_rulefirstpat(fn, &fn->gsub[i]));
 612         for (i = 0; i < fn->gpos_n; i++)
 613                 font_isetinsert(fn, fn->gpos0, i,
 614                         font_rulefirstpat(fn, &fn->gpos[i]));
 615         fn->scrp = -1;
 616         return fn;
 617 }
 618
 619 void font_close(struct font *fn)
 620 {
 621         int i;
 622         for (i = 0; i < fn->gsub_n; i++)
 623                 free(fn->gsub[i].pats);
 624         for (i = 0; i < fn->gpos_n; i++)
 625                 free(fn->gpos[i].pats);
 626         dict_free(fn->gl_dict);
 627         dict_free(fn->ch_dict);
 628         dict_free(fn->ch_map);
 629         iset_free(fn->gsub0);
 630         iset_free(fn->gpos0);
 631         iset_free(fn->ggrp);
 632         free(fn->gsub);
 633         free(fn->gpos);
 634         free(fn->gl);
 635         free(fn);
 636 }
 637
 638 int font_special(struct font *fn)
 639 {
 640         return fn->special;
 641 }
 642
 643 /* return width w for the given font and size */
 644 int font_wid(struct font *fn, int sz, int w)
 645 {
 646         sz = font_zoom(fn, sz);
 647         return w >= 0 ? DEVWID(sz, w) : -DEVWID(sz, -w);
 648 }
 649
 650 /* return track kerning width for the given size */
 651 static int font_twid(struct font *fn, int sz)
 652 {
 653         if (fn->s1 >= 0 && sz <= fn->s1)
 654                 return fn->n1 * SC_PT;
 655         if (fn->s2 >= 0 && sz >= fn->s2)
 656                 return fn->n2 * SC_PT;
 657         if (sz > fn->s1 && sz < fn->s2)
 658                 return ((sz - fn->s1) * fn->n1 + (fn->s2 - sz) * fn->n2) *
 659                                 (long) SC_PT / (fn->s2 - fn->s1);
 660         return 0;
 661 }
 662
 663 /* glyph width, where cfn is the current font and fn is glyph's font */
 664 int font_gwid(struct font *fn, struct font *cfn, int sz, int w)
 665 {
 666         struct font *xfn = cfn ? cfn : fn;
 667         if (xfn->cs)
 668                 return xfn->cs * (font_zoom(fn, xfn->cs_ps ? xfn->cs_ps : sz)
 669                                         * SC_IN / 72) / 36;
 670         return font_wid(fn, sz, w) + (cfn ? font_twid(fn, sz) : 0) +
 671                 (font_getbd(xfn) ? font_getbd(xfn) - 1 : 0);
 672 }
 673
 674 /* space width for the give word space or sentence space */
 675 int font_swid(struct font *fn, int sz, int ss)
 676 {
 677         return font_gwid(fn, NULL, sz, (fn->spacewid * ss + 6) / 12);
 678 }
 679
 680 int font_getcs(struct font *fn)
 681 {
 682         return fn->cs;
 683 }
 684
 685 void font_setcs(struct font *fn, int cs, int ps)
 686 {
 687         fn->cs = cs;
 688         fn->cs_ps = ps;
 689 }
 690
 691 int font_getbd(struct font *fn)
 692 {
 693         return fn->bd;
 694 }
 695
 696 void font_setbd(struct font *fn, int bd)
 697 {
 698         fn->bd = bd;
 699 }
 700
 701 void font_track(struct font *fn, int s1, int n1, int s2, int n2)
 702 {
 703         fn->s1 = s1;
 704         fn->n1 = n1;
 705         fn->s2 = s2;
 706         fn->n2 = n2;
 707 }
 708
 709 int font_zoom(struct font *fn, int sz)
 710 {
 711         return fn->zoom ? (sz * fn->zoom + 500) / 1000 : sz;
 712 }
 713
 714 void font_setzoom(struct font *fn, int zoom)
 715 {
 716         fn->zoom = zoom;
 717 }
 718
 719 /* enable/disable font features; returns the previous value */
 720 int font_feat(struct font *fn, char *name, int val)
 721 {
 722         int idx = font_findfeat(fn, name);
 723         int old = idx >= 0 ? fn->feat_set[idx] : 0;
 724         if (idx >= 0)
 725                 fn->feat_set[idx] = val != 0;
 726         return old;
 727 }
 728
 729 /* set font script */
 730 void font_scrp(struct font *fn, char *name)
 731 {
 732         fn->scrp = name ? font_findscrp(fn, name) : -1;
 733 }