| 1 | #ifndef lint | 
| 2 | static const char RCSid[] = "$Id: wfconv.c,v 2.11 2014/01/24 01:26:44 greg Exp $"; | 
| 3 | #endif | 
| 4 | /* | 
| 5 | *  Load Wavefront .OBJ file and convert to triangles with mesh info. | 
| 6 | *  Code borrowed largely from obj2rad.c | 
| 7 | */ | 
| 8 |  | 
| 9 | #include "copyright.h" | 
| 10 | #include "standard.h" | 
| 11 | #include "cvmesh.h" | 
| 12 | #include "triangulate.h" | 
| 13 | #include <ctype.h> | 
| 14 |  | 
| 15 | typedef int     VNDX[3];        /* vertex index (point,map,normal) */ | 
| 16 |  | 
| 17 | #define CHUNKSIZ        1024    /* vertex allocation chunk size */ | 
| 18 |  | 
| 19 | #define MAXARG          512     /* maximum # arguments in a statement */ | 
| 20 |  | 
| 21 | static FVECT    *vlist;         /* our vertex list */ | 
| 22 | static int      nvs;            /* number of vertices in our list */ | 
| 23 | static FVECT    *vnlist;        /* vertex normal list */ | 
| 24 | static int      nvns; | 
| 25 | static RREAL    (*vtlist)[2];   /* map vertex list */ | 
| 26 | static int      nvts; | 
| 27 |  | 
| 28 | static char     *inpfile;       /* input file name */ | 
| 29 | static int      havemats;       /* materials available? */ | 
| 30 | static char     material[256];  /* current material name */ | 
| 31 | static char     group[256];     /* current group name */ | 
| 32 | static int      lineno;         /* current line number */ | 
| 33 | static int      faceno;         /* current face number */ | 
| 34 |  | 
| 35 | static int getstmt(char *av[MAXARG], FILE       *fp); | 
| 36 | static int cvtndx(VNDX  vi, char        *vs); | 
| 37 | static int putface(int  ac, char        **av); | 
| 38 | static OBJECT getmod(void); | 
| 39 | static int puttri(char  *v1, char       *v2, char       *v3); | 
| 40 | static void freeverts(void); | 
| 41 | static int newv(double  x, double       y, double       z); | 
| 42 | static int newvn(double x, double       y, double       z); | 
| 43 | static int newvt(double x, double       y); | 
| 44 | static void syntax(char *er); | 
| 45 |  | 
| 46 |  | 
| 47 | void | 
| 48 | wfreadobj(              /* read in .OBJ file and convert */ | 
| 49 | char    *objfn | 
| 50 | ) | 
| 51 | { | 
| 52 | FILE    *fp; | 
| 53 | char    *argv[MAXARG]; | 
| 54 | int     argc; | 
| 55 | int     nstats, nunknown; | 
| 56 |  | 
| 57 | if (objfn == NULL) { | 
| 58 | inpfile = "<stdin>"; | 
| 59 | fp = stdin; | 
| 60 | } else if ((fp = fopen(inpfile=objfn, "r")) == NULL) { | 
| 61 | sprintf(errmsg, "cannot open \"%s\"", inpfile); | 
| 62 | error(USER, errmsg); | 
| 63 | } | 
| 64 | havemats = (nobjects > 0); | 
| 65 | nstats = nunknown = 0; | 
| 66 | material[0] = '\0'; | 
| 67 | group[0] = '\0'; | 
| 68 | lineno = 0; faceno = 0; | 
| 69 | /* scan until EOF */ | 
| 70 | while ( (argc = getstmt(argv, fp)) ) { | 
| 71 | switch (argv[0][0]) { | 
| 72 | case 'v':               /* vertex */ | 
| 73 | switch (argv[0][1]) { | 
| 74 | case '\0':                      /* point */ | 
| 75 | if (badarg(argc-1,argv+1,"fff")) | 
| 76 | syntax("bad vertex"); | 
| 77 | newv(atof(argv[1]), atof(argv[2]), | 
| 78 | atof(argv[3])); | 
| 79 | break; | 
| 80 | case 'n':                       /* normal */ | 
| 81 | if (argv[0][2]) | 
| 82 | goto unknown; | 
| 83 | if (badarg(argc-1,argv+1,"fff")) | 
| 84 | syntax("bad normal"); | 
| 85 | if (!newvn(atof(argv[1]), atof(argv[2]), | 
| 86 | atof(argv[3]))) | 
| 87 | syntax("zero normal"); | 
| 88 | break; | 
| 89 | case 't':                       /* coordinate */ | 
| 90 | if (argv[0][2]) | 
| 91 | goto unknown; | 
| 92 | if (badarg(argc-1,argv+1,"ff")) | 
| 93 | goto unknown; | 
| 94 | newvt(atof(argv[1]), atof(argv[2])); | 
| 95 | break; | 
| 96 | default: | 
| 97 | goto unknown; | 
| 98 | } | 
| 99 | break; | 
| 100 | case 'f':                               /* face */ | 
| 101 | if (argv[0][1]) | 
| 102 | goto unknown; | 
| 103 | faceno++; | 
| 104 | switch (argc-1) { | 
| 105 | case 0: case 1: case 2: | 
| 106 | syntax("too few vertices"); | 
| 107 | break; | 
| 108 | case 3: | 
| 109 | if (!puttri(argv[1], argv[2], argv[3])) | 
| 110 | syntax("bad triangle"); | 
| 111 | break; | 
| 112 | default: | 
| 113 | if (!putface(argc-1, argv+1)) | 
| 114 | syntax("bad face"); | 
| 115 | break; | 
| 116 | } | 
| 117 | break; | 
| 118 | case 'u':                               /* usemtl/usemap */ | 
| 119 | if (!strcmp(argv[0], "usemap")) | 
| 120 | break; | 
| 121 | if (strcmp(argv[0], "usemtl")) | 
| 122 | goto unknown; | 
| 123 | if (argc > 1) | 
| 124 | strcpy(material, argv[1]); | 
| 125 | else | 
| 126 | material[0] = '\0'; | 
| 127 | break; | 
| 128 | case 'o':               /* object name */ | 
| 129 | if (argv[0][1]) | 
| 130 | goto unknown; | 
| 131 | break; | 
| 132 | case 'g':               /* group name */ | 
| 133 | if (argv[0][1]) | 
| 134 | goto unknown; | 
| 135 | if (argc > 1) | 
| 136 | strcpy(group, argv[1]); | 
| 137 | else | 
| 138 | group[0] = '\0'; | 
| 139 | break; | 
| 140 | case '#':               /* comment */ | 
| 141 | break; | 
| 142 | default:;               /* something we don't deal with */ | 
| 143 | unknown: | 
| 144 | nunknown++; | 
| 145 | break; | 
| 146 | } | 
| 147 | nstats++; | 
| 148 | } | 
| 149 | /* clean up */ | 
| 150 | freeverts(); | 
| 151 | fclose(fp); | 
| 152 | if (nunknown > 0) { | 
| 153 | sprintf(errmsg, "%d of %d statements unrecognized", | 
| 154 | nunknown, nstats); | 
| 155 | error(WARNING, errmsg); | 
| 156 | } | 
| 157 | } | 
| 158 |  | 
| 159 |  | 
| 160 | static int | 
| 161 | getstmt(                                /* read the next statement from fp */ | 
| 162 | char    *av[MAXARG], | 
| 163 | FILE    *fp | 
| 164 | ) | 
| 165 | { | 
| 166 | static char     sbuf[MAXARG*16]; | 
| 167 | char    *cp; | 
| 168 | int     i; | 
| 169 |  | 
| 170 | do { | 
| 171 | if (fgetline(cp=sbuf, sizeof(sbuf), fp) == NULL) | 
| 172 | return(0); | 
| 173 | i = 0; | 
| 174 | for ( ; ; ) { | 
| 175 | while (isspace(*cp) || *cp == '\\') { | 
| 176 | if (*cp == '\n') | 
| 177 | lineno++; | 
| 178 | *cp++ = '\0'; | 
| 179 | } | 
| 180 | if (!*cp) | 
| 181 | break; | 
| 182 | if (i >= MAXARG-1) { | 
| 183 | sprintf(errmsg, | 
| 184 | "%s: too many arguments near line %d (limit %d)\n", | 
| 185 | inpfile, lineno+1, MAXARG-1); | 
| 186 | break; | 
| 187 | } | 
| 188 | av[i++] = cp; | 
| 189 | while (*++cp && !isspace(*cp)) | 
| 190 | ; | 
| 191 | } | 
| 192 | av[i] = NULL; | 
| 193 | lineno++; | 
| 194 | } while (!i); | 
| 195 |  | 
| 196 | return(i); | 
| 197 | } | 
| 198 |  | 
| 199 |  | 
| 200 | static int | 
| 201 | cvtndx(                         /* convert vertex string to index */ | 
| 202 | VNDX    vi, | 
| 203 | char    *vs | 
| 204 | ) | 
| 205 | { | 
| 206 | /* get point */ | 
| 207 | vi[0] = atoi(vs); | 
| 208 | if (vi[0] > 0) { | 
| 209 | if (vi[0]-- > nvs) | 
| 210 | return(0); | 
| 211 | } else if (vi[0] < 0) { | 
| 212 | vi[0] += nvs; | 
| 213 | if (vi[0] < 0) | 
| 214 | return(0); | 
| 215 | } else | 
| 216 | return(0); | 
| 217 | /* get map coord. */ | 
| 218 | while (*vs) | 
| 219 | if (*vs++ == '/') | 
| 220 | break; | 
| 221 | vi[1] = atoi(vs); | 
| 222 | if (vi[1] > 0) { | 
| 223 | if (vi[1]-- > nvts) | 
| 224 | return(0); | 
| 225 | } else if (vi[1] < 0) { | 
| 226 | vi[1] += nvts; | 
| 227 | if (vi[1] < 0) | 
| 228 | return(0); | 
| 229 | } else | 
| 230 | vi[1] = -1; | 
| 231 | /* get normal */ | 
| 232 | while (*vs) | 
| 233 | if (*vs++ == '/') | 
| 234 | break; | 
| 235 | vi[2] = atoi(vs); | 
| 236 | if (vi[2] > 0) { | 
| 237 | if (vi[2]-- > nvns) | 
| 238 | return(0); | 
| 239 | } else if (vi[2] < 0) { | 
| 240 | vi[2] += nvns; | 
| 241 | if (vi[2] < 0) | 
| 242 | return(0); | 
| 243 | } else | 
| 244 | vi[2] = -1; | 
| 245 | return(1); | 
| 246 | } | 
| 247 |  | 
| 248 | /* determine dominant axis for triangle */ | 
| 249 | static int | 
| 250 | dominant_axis(char *v1, char *v2, char *v3) | 
| 251 | { | 
| 252 | VNDX    v1i, v2i, v3i; | 
| 253 | FVECT   e1, e2, vn; | 
| 254 | int     i, imax; | 
| 255 |  | 
| 256 | if (!cvtndx(v1i, v1) || !cvtndx(v2i, v2) || !cvtndx(v3i, v3)) | 
| 257 | return(-1); | 
| 258 | VSUB(e1, vlist[v2i[0]], vlist[v1i[0]]); | 
| 259 | VSUB(e2, vlist[v3i[0]], vlist[v2i[0]]); | 
| 260 | VCROSS(vn, e1, e2); | 
| 261 | for (i = imax = 2; i--; ) | 
| 262 | if (vn[i]*vn[i] > vn[imax]*vn[imax]) | 
| 263 | imax = i; | 
| 264 | return(vn[imax]*vn[imax] > FTINY ? imax : -1); | 
| 265 | } | 
| 266 |  | 
| 267 | /* callback for triangle output from polygon */ | 
| 268 | static int | 
| 269 | tri_out(const Vert2_list *tp, int a, int b, int c) | 
| 270 | { | 
| 271 | return( puttri( ((char **)tp->p)[a], | 
| 272 | ((char **)tp->p)[b], | 
| 273 | ((char **)tp->p)[c] ) ); | 
| 274 | } | 
| 275 |  | 
| 276 | static int | 
| 277 | putface(                                /* put out an N-sided polygon */ | 
| 278 | int     ac, | 
| 279 | char    **av | 
| 280 | ) | 
| 281 | { | 
| 282 | Vert2_list      *poly = polyAlloc(ac); | 
| 283 | int             i, ax, ay; | 
| 284 |  | 
| 285 | if (poly == NULL) | 
| 286 | return(0); | 
| 287 | poly->p = (void *)av; | 
| 288 | for (i = ac-3; i >= 0; i--)     /* identify dominant axis */ | 
| 289 | if ((ax = dominant_axis(av[i], av[i+1], av[i+2])) >= 0) | 
| 290 | break; | 
| 291 | if (ax < 0) | 
| 292 | return(1);              /* ignore degenerate face */ | 
| 293 | if (++ax >= 3) ax = 0; | 
| 294 | ay = ax; | 
| 295 | if (++ay >= 3) ay = 0; | 
| 296 | for (i = 0; i < ac; i++) {      /* convert to 2-D polygon */ | 
| 297 | VNDX    vi; | 
| 298 | if (!cvtndx(vi, av[i])) { | 
| 299 | error(WARNING, "bad vertex reference"); | 
| 300 | polyFree(poly); | 
| 301 | return(0); | 
| 302 | } | 
| 303 | poly->v[i].mX = vlist[vi[0]][ax]; | 
| 304 | poly->v[i].mY = vlist[vi[0]][ay]; | 
| 305 | } | 
| 306 | /* break into triangles & output */ | 
| 307 | if (!polyTriangulate(poly, &tri_out)) | 
| 308 | error(WARNING, "self-intersecting face"); | 
| 309 | polyFree(poly); | 
| 310 | return(1); | 
| 311 | } | 
| 312 |  | 
| 313 |  | 
| 314 | static OBJECT | 
| 315 | getmod(void)                            /* get current modifier ID */ | 
| 316 | { | 
| 317 | char    *mnam; | 
| 318 | OBJECT  mod; | 
| 319 |  | 
| 320 | if (!havemats) | 
| 321 | return(OVOID); | 
| 322 | if (!strcmp(material, VOIDID)) | 
| 323 | return(OVOID); | 
| 324 | if (material[0])                /* prefer usemtl statements */ | 
| 325 | mnam = material; | 
| 326 | else if (group[0])              /* else use group name */ | 
| 327 | mnam = group; | 
| 328 | else | 
| 329 | return(OVOID); | 
| 330 | mod = modifier(mnam); | 
| 331 | if (mod == OVOID) { | 
| 332 | sprintf(errmsg, "%s: undefined modifier \"%s\"", | 
| 333 | inpfile, mnam); | 
| 334 | error(USER, errmsg); | 
| 335 | } | 
| 336 | return(mod); | 
| 337 | } | 
| 338 |  | 
| 339 |  | 
| 340 | static int | 
| 341 | puttri(                 /* convert a triangle */ | 
| 342 | char    *v1, | 
| 343 | char    *v2, | 
| 344 | char    *v3 | 
| 345 | ) | 
| 346 | { | 
| 347 | VNDX    v1i, v2i, v3i; | 
| 348 | RREAL   *v1c, *v2c, *v3c; | 
| 349 | RREAL   *v1n, *v2n, *v3n; | 
| 350 |  | 
| 351 | if (!cvtndx(v1i, v1) || !cvtndx(v2i, v2) || !cvtndx(v3i, v3)) { | 
| 352 | error(WARNING, "bad vertex reference"); | 
| 353 | return(0); | 
| 354 | } | 
| 355 | if (v1i[1]>=0 && v2i[1]>=0 && v3i[1]>=0) { | 
| 356 | v1c = vtlist[v1i[1]]; | 
| 357 | v2c = vtlist[v2i[1]]; | 
| 358 | v3c = vtlist[v3i[1]]; | 
| 359 | } else | 
| 360 | v1c = v2c = v3c = NULL; | 
| 361 |  | 
| 362 | if (v1i[2]>=0 && v2i[2]>=0 && v3i[2]>=0) { | 
| 363 | v1n = vnlist[v1i[2]]; | 
| 364 | v2n = vnlist[v2i[2]]; | 
| 365 | v3n = vnlist[v3i[2]]; | 
| 366 | } else | 
| 367 | v1n = v2n = v3n = NULL; | 
| 368 |  | 
| 369 | return(cvtri(getmod(), vlist[v1i[0]], vlist[v2i[0]], vlist[v3i[0]], | 
| 370 | v1n, v2n, v3n, v1c, v2c, v3c) >= 0); | 
| 371 | } | 
| 372 |  | 
| 373 |  | 
| 374 | static void | 
| 375 | freeverts(void)                 /* free all vertices */ | 
| 376 | { | 
| 377 | if (nvs) { | 
| 378 | free((void *)vlist); | 
| 379 | nvs = 0; | 
| 380 | } | 
| 381 | if (nvts) { | 
| 382 | free((void *)vtlist); | 
| 383 | nvts = 0; | 
| 384 | } | 
| 385 | if (nvns) { | 
| 386 | free((void *)vnlist); | 
| 387 | nvns = 0; | 
| 388 | } | 
| 389 | } | 
| 390 |  | 
| 391 |  | 
| 392 | static int | 
| 393 | newv(                   /* create a new vertex */ | 
| 394 | double  x, | 
| 395 | double  y, | 
| 396 | double  z | 
| 397 | ) | 
| 398 | { | 
| 399 | if (!(nvs%CHUNKSIZ)) {          /* allocate next block */ | 
| 400 | if (nvs == 0) | 
| 401 | vlist = (FVECT *)malloc(CHUNKSIZ*sizeof(FVECT)); | 
| 402 | else | 
| 403 | vlist = (FVECT *)realloc((void *)vlist, | 
| 404 | (nvs+CHUNKSIZ)*sizeof(FVECT)); | 
| 405 | if (vlist == NULL) | 
| 406 | error(SYSTEM, "out of memory in newv"); | 
| 407 | } | 
| 408 | /* assign new vertex */ | 
| 409 | vlist[nvs][0] = x; | 
| 410 | vlist[nvs][1] = y; | 
| 411 | vlist[nvs][2] = z; | 
| 412 | return(++nvs); | 
| 413 | } | 
| 414 |  | 
| 415 |  | 
| 416 | static int | 
| 417 | newvn(                  /* create a new vertex normal */ | 
| 418 | double  x, | 
| 419 | double  y, | 
| 420 | double  z | 
| 421 | ) | 
| 422 | { | 
| 423 | if (!(nvns%CHUNKSIZ)) {         /* allocate next block */ | 
| 424 | if (nvns == 0) | 
| 425 | vnlist = (FVECT *)malloc(CHUNKSIZ*sizeof(FVECT)); | 
| 426 | else | 
| 427 | vnlist = (FVECT *)realloc((void *)vnlist, | 
| 428 | (nvns+CHUNKSIZ)*sizeof(FVECT)); | 
| 429 | if (vnlist == NULL) | 
| 430 | error(SYSTEM, "out of memory in newvn"); | 
| 431 | } | 
| 432 | /* assign new normal */ | 
| 433 | vnlist[nvns][0] = x; | 
| 434 | vnlist[nvns][1] = y; | 
| 435 | vnlist[nvns][2] = z; | 
| 436 | if (normalize(vnlist[nvns]) == 0.0) | 
| 437 | return(0); | 
| 438 | return(++nvns); | 
| 439 | } | 
| 440 |  | 
| 441 |  | 
| 442 | static int | 
| 443 | newvt(                  /* create a new texture map vertex */ | 
| 444 | double  x, | 
| 445 | double  y | 
| 446 | ) | 
| 447 | { | 
| 448 | if (!(nvts%CHUNKSIZ)) {         /* allocate next block */ | 
| 449 | if (nvts == 0) | 
| 450 | vtlist = (RREAL (*)[2])malloc(CHUNKSIZ*2*sizeof(RREAL)); | 
| 451 | else | 
| 452 | vtlist = (RREAL (*)[2])realloc((void *)vtlist, | 
| 453 | (nvts+CHUNKSIZ)*2*sizeof(RREAL)); | 
| 454 | if (vtlist == NULL) | 
| 455 | error(SYSTEM, "out of memory in newvt"); | 
| 456 | } | 
| 457 | /* assign new vertex */ | 
| 458 | vtlist[nvts][0] = x; | 
| 459 | vtlist[nvts][1] = y; | 
| 460 | return(++nvts); | 
| 461 | } | 
| 462 |  | 
| 463 |  | 
| 464 | static void | 
| 465 | syntax(                 /* report syntax error and exit */ | 
| 466 | char    *er | 
| 467 | ) | 
| 468 | { | 
| 469 | sprintf(errmsg, "%s: Wavefront syntax error near line %d: %s\n", | 
| 470 | inpfile, lineno, er); | 
| 471 | error(USER, errmsg); | 
| 472 | } |