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root/radiance/ray/src/gen/gensurf.c
Revision: 2.13
Committed: Sun Nov 16 10:29:38 2003 UTC (20 years, 4 months ago) by schorsch
Content type: text/plain
Branch: MAIN
Changes since 2.12: +66 -30 lines
Log Message:
Continued ANSIfication and reduced other compile warnings.

File Contents

# Content
1 #ifndef lint
2 static const char RCSid[] = "$Id: gensurf.c,v 2.12 2003/08/04 22:37:53 greg Exp $";
3 #endif
4 /*
5 * gensurf.c - program to generate functional surfaces
6 *
7 * Parametric functions x(s,t), y(s,t) and z(s,t)
8 * specify the surface, which is tesselated into an m by n
9 * array of paired triangles.
10 * The surface normal is defined by the right hand
11 * rule applied to (s,t).
12 *
13 * 4/3/87
14 *
15 * 4/16/02 Added conditional vertex output
16 */
17
18 #include "rtmath.h"
19 #include "rterror.h"
20 #include "rtio.h"
21 #include "calcomp.h"
22
23 char XNAME[] = "X`SYS"; /* x function name */
24 char YNAME[] = "Y`SYS"; /* y function name */
25 char ZNAME[] = "Z`SYS"; /* z function name */
26
27 char VNAME[] = "valid"; /* valid vertex name */
28
29 #define ABS(x) ((x)>=0 ? (x) : -(x))
30
31 #define ZEROVECT(v) (DOT(v,v) <= FTINY*FTINY)
32
33 #define pvect(p) printf(vformat, (p)[0], (p)[1], (p)[2])
34
35 char vformat[] = "%15.9g %15.9g %15.9g\n";
36 char tsargs[] = "4 surf_dx surf_dy surf_dz surf.cal\n";
37 char texname[] = "Phong";
38
39 int smooth = 0; /* apply smoothing? */
40 int objout = 0; /* output .OBJ format? */
41
42 char *modname, *surfname;
43
44 /* recorded data flags */
45 #define HASBORDER 01
46 #define TRIPLETS 02
47 /* a data structure */
48 struct {
49 int flags; /* data type */
50 short m, n; /* number of s and t values */
51 RREAL *data; /* the data itself, s major sort */
52 } datarec; /* our recorded data */
53
54 /* XXX this is redundant with rt/noise3.c, should go to a library */
55 double l_hermite(), l_bezier(), l_bspline(), l_dataval();
56
57 typedef struct {
58 int valid; /* point is valid (vertex number) */
59 FVECT p; /* vertex position */
60 FVECT n; /* average normal */
61 RREAL uv[2]; /* (u,v) position */
62 } POINT;
63
64
65 void loaddata(char *file, int m, int n, int pointsize);
66 double l_dataval(char *nam);
67 void putobjrow(POINT *rp, int n);
68 void putsquare(POINT *p0, POINT *p1, POINT *p2, POINT *p3);
69 void comprow(double s, POINT *row, int siz);
70 void compnorms(POINT *r0, POINT *r1, POINT *r2, int siz);
71 int norminterp(FVECT resmat[4], POINT *p0, POINT *p1, POINT *p2, POINT *p3);
72 void printhead(int ac, char **av);
73
74
75 int
76 main(argc, argv)
77 int argc;
78 char *argv[];
79 {
80 POINT *row0, *row1, *row2, *rp;
81 int i, j, m, n;
82 char stmp[256];
83
84 varset("PI", ':', PI);
85 funset("hermite", 5, ':', l_hermite);
86 funset("bezier", 5, ':', l_bezier);
87 funset("bspline", 5, ':', l_bspline);
88
89 if (argc < 8)
90 goto userror;
91
92 for (i = 8; i < argc; i++)
93 if (!strcmp(argv[i], "-e"))
94 scompile(argv[++i], NULL, 0);
95 else if (!strcmp(argv[i], "-f"))
96 fcompile(argv[++i]);
97 else if (!strcmp(argv[i], "-s"))
98 smooth++;
99 else if (!strcmp(argv[i], "-o"))
100 objout++;
101 else
102 goto userror;
103
104 modname = argv[1];
105 surfname = argv[2];
106 m = atoi(argv[6]);
107 n = atoi(argv[7]);
108 if (m <= 0 || n <= 0)
109 goto userror;
110 if (!strcmp(argv[5], "-") || access(argv[5], 4) == 0) { /* file? */
111 funset(ZNAME, 2, ':', l_dataval);
112 if (!strcmp(argv[5],argv[3]) && !strcmp(argv[5],argv[4])) {
113 loaddata(argv[5], m, n, 3);
114 funset(XNAME, 2, ':', l_dataval);
115 funset(YNAME, 2, ':', l_dataval);
116 } else {
117 loaddata(argv[5], m, n, 1);
118 sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
119 scompile(stmp, NULL, 0);
120 sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
121 scompile(stmp, NULL, 0);
122 }
123 } else {
124 sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
125 scompile(stmp, NULL, 0);
126 sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
127 scompile(stmp, NULL, 0);
128 sprintf(stmp, "%s(s,t)=%s;", ZNAME, argv[5]);
129 scompile(stmp, NULL, 0);
130 }
131 row0 = (POINT *)malloc((n+3)*sizeof(POINT));
132 row1 = (POINT *)malloc((n+3)*sizeof(POINT));
133 row2 = (POINT *)malloc((n+3)*sizeof(POINT));
134 if (row0 == NULL || row1 == NULL || row2 == NULL) {
135 fprintf(stderr, "%s: out of memory\n", argv[0]);
136 quit(1);
137 }
138 row0++; row1++; row2++;
139 /* print header */
140 printhead(argc, argv);
141 eclock = 0;
142 /* initialize */
143 comprow(-1.0/m, row0, n);
144 comprow(0.0, row1, n);
145 comprow(1.0/m, row2, n);
146 compnorms(row0, row1, row2, n);
147 if (objout) {
148 printf("\nusemtl %s\n\n", modname);
149 putobjrow(row1, n);
150 }
151 /* for each row */
152 for (i = 0; i < m; i++) {
153 /* compute next row */
154 rp = row0;
155 row0 = row1;
156 row1 = row2;
157 row2 = rp;
158 comprow((double)(i+2)/m, row2, n);
159 compnorms(row0, row1, row2, n);
160 if (objout)
161 putobjrow(row1, n);
162
163 for (j = 0; j < n; j++) {
164 int orient = (j & 1);
165 /* put polygons */
166 if (!(row0[j].valid && row1[j+1].valid))
167 orient = 1;
168 else if (!(row1[j].valid && row0[j+1].valid))
169 orient = 0;
170 if (orient)
171 putsquare(&row0[j], &row1[j],
172 &row0[j+1], &row1[j+1]);
173 else
174 putsquare(&row1[j], &row1[j+1],
175 &row0[j], &row0[j+1]);
176 }
177 }
178
179 return 0;
180
181 userror:
182 fprintf(stderr, "Usage: %s material name ", argv[0]);
183 fprintf(stderr, "x(s,t) y(s,t) z(s,t) m n [-s][-e expr][-f file]\n");
184 return 1;
185 }
186
187
188 void
189 loaddata( /* load point data from file */
190 char *file,
191 int m,
192 int n,
193 int pointsize
194 )
195 {
196 FILE *fp;
197 char word[64];
198 register int size;
199 register RREAL *dp;
200
201 datarec.flags = HASBORDER; /* assume border values */
202 datarec.m = m+1;
203 datarec.n = n+1;
204 size = datarec.m*datarec.n*pointsize;
205 if (pointsize == 3)
206 datarec.flags |= TRIPLETS;
207 dp = (RREAL *)malloc(size*sizeof(RREAL));
208 if ((datarec.data = dp) == NULL) {
209 fputs("Out of memory\n", stderr);
210 exit(1);
211 }
212 if (!strcmp(file, "-")) {
213 file = "<stdin>";
214 fp = stdin;
215 } else if ((fp = fopen(file, "r")) == NULL) {
216 fputs(file, stderr);
217 fputs(": cannot open\n", stderr);
218 exit(1);
219 }
220 while (size > 0 && fgetword(word, sizeof(word), fp) != NULL) {
221 if (!isflt(word)) {
222 fprintf(stderr, "%s: garbled data value: %s\n",
223 file, word);
224 exit(1);
225 }
226 *dp++ = atof(word);
227 size--;
228 }
229 if (size == (m+n+1)*pointsize) { /* no border after all */
230 dp = (RREAL *)realloc((void *)datarec.data,
231 m*n*pointsize*sizeof(RREAL));
232 if (dp != NULL)
233 datarec.data = dp;
234 datarec.flags &= ~HASBORDER;
235 datarec.m = m;
236 datarec.n = n;
237 size = 0;
238 }
239 if (datarec.m < 2 || datarec.n < 2 || size != 0 ||
240 fgetword(word, sizeof(word), fp) != NULL) {
241 fputs(file, stderr);
242 fputs(": bad number of data points\n", stderr);
243 exit(1);
244 }
245 fclose(fp);
246 }
247
248
249 double
250 l_dataval( /* return recorded data value */
251 char *nam
252 )
253 {
254 double u, v;
255 register int i, j;
256 register RREAL *dp;
257 double d00, d01, d10, d11;
258 /* compute coordinates */
259 u = argument(1); v = argument(2);
260 if (datarec.flags & HASBORDER) {
261 i = u *= datarec.m-1;
262 j = v *= datarec.n-1;
263 } else {
264 i = u = u*datarec.m - .5;
265 j = v = v*datarec.n - .5;
266 }
267 if (i < 0) i = 0;
268 else if (i > datarec.m-2) i = datarec.m-2;
269 if (j < 0) j = 0;
270 else if (j > datarec.n-2) j = datarec.n-2;
271 /* compute value */
272 if (datarec.flags & TRIPLETS) {
273 dp = datarec.data + 3*(j*datarec.m + i);
274 if (nam == ZNAME)
275 dp += 2;
276 else if (nam == YNAME)
277 dp++;
278 d00 = dp[0]; d01 = dp[3];
279 dp += 3*datarec.m;
280 d10 = dp[0]; d11 = dp[3];
281 } else {
282 dp = datarec.data + j*datarec.m + i;
283 d00 = dp[0]; d01 = dp[1];
284 dp += datarec.m;
285 d10 = dp[0]; d11 = dp[1];
286 }
287 /* bilinear interpolation */
288 return((j+1-v)*((i+1-u)*d00+(u-i)*d01)+(v-j)*((i+1-u)*d10+(u-i)*d11));
289 }
290
291
292 void
293 putobjrow( /* output vertex row to .OBJ */
294 register POINT *rp,
295 int n
296 )
297 {
298 static int nverts = 0;
299
300 for ( ; n-- >= 0; rp++) {
301 if (!rp->valid)
302 continue;
303 fputs("v ", stdout);
304 pvect(rp->p);
305 if (smooth && !ZEROVECT(rp->n))
306 printf("\tvn %.9g %.9g %.9g\n",
307 rp->n[0], rp->n[1], rp->n[2]);
308 printf("\tvt %.9g %.9g\n", rp->uv[0], rp->uv[1]);
309 rp->valid = ++nverts;
310 }
311 }
312
313
314 void
315 putsquare( /* put out a square */
316 POINT *p0,
317 POINT *p1,
318 POINT *p2,
319 POINT *p3
320 )
321 {
322 static int nout = 0;
323 FVECT norm[4];
324 int axis;
325 FVECT v1, v2, vc1, vc2;
326 int ok1, ok2;
327 /* compute exact normals */
328 ok1 = (p0->valid && p1->valid && p2->valid);
329 if (ok1) {
330 VSUB(v1, p1->p, p0->p);
331 VSUB(v2, p2->p, p0->p);
332 fcross(vc1, v1, v2);
333 ok1 = (normalize(vc1) != 0.0);
334 }
335 ok2 = (p1->valid && p2->valid && p3->valid);
336 if (ok2) {
337 VSUB(v1, p2->p, p3->p);
338 VSUB(v2, p1->p, p3->p);
339 fcross(vc2, v1, v2);
340 ok2 = (normalize(vc2) != 0.0);
341 }
342 if (!(ok1 | ok2))
343 return;
344 if (objout) { /* output .OBJ faces */
345 int p0n=0, p1n=0, p2n=0, p3n=0;
346 if (smooth) {
347 if (!ZEROVECT(p0->n))
348 p0n = p0->valid;
349 if (!ZEROVECT(p1->n))
350 p1n = p1->valid;
351 if (!ZEROVECT(p2->n))
352 p2n = p2->valid;
353 if (!ZEROVECT(p3->n))
354 p3n = p3->valid;
355 }
356 if (ok1 & ok2 && fdot(vc1,vc2) >= 1.0-FTINY*FTINY) {
357 printf("f %d/%d/%d %d/%d/%d %d/%d/%d %d/%d/%d\n",
358 p0->valid, p0->valid, p0n,
359 p1->valid, p1->valid, p1n,
360 p3->valid, p3->valid, p3n,
361 p2->valid, p2->valid, p2n);
362 return;
363 }
364 if (ok1)
365 printf("f %d/%d/%d %d/%d/%d %d/%d/%d\n",
366 p0->valid, p0->valid, p0n,
367 p1->valid, p1->valid, p1n,
368 p2->valid, p2->valid, p2n);
369 if (ok2)
370 printf("f %d/%d/%d %d/%d/%d %d/%d/%d\n",
371 p2->valid, p2->valid, p2n,
372 p1->valid, p1->valid, p1n,
373 p3->valid, p3->valid, p3n);
374 return;
375 }
376 /* compute normal interpolation */
377 axis = norminterp(norm, p0, p1, p2, p3);
378
379 /* put out quadrilateral? */
380 if (ok1 & ok2 && fdot(vc1,vc2) >= 1.0-FTINY*FTINY) {
381 printf("\n%s ", modname);
382 if (axis != -1) {
383 printf("texfunc %s\n", texname);
384 printf(tsargs);
385 printf("0\n13\t%d\n", axis);
386 pvect(norm[0]);
387 pvect(norm[1]);
388 pvect(norm[2]);
389 fvsum(v1, norm[3], vc1, -0.5);
390 fvsum(v1, v1, vc2, -0.5);
391 pvect(v1);
392 printf("\n%s ", texname);
393 }
394 printf("polygon %s.%d\n", surfname, ++nout);
395 printf("0\n0\n12\n");
396 pvect(p0->p);
397 pvect(p1->p);
398 pvect(p3->p);
399 pvect(p2->p);
400 return;
401 }
402 /* put out triangles? */
403 if (ok1) {
404 printf("\n%s ", modname);
405 if (axis != -1) {
406 printf("texfunc %s\n", texname);
407 printf(tsargs);
408 printf("0\n13\t%d\n", axis);
409 pvect(norm[0]);
410 pvect(norm[1]);
411 pvect(norm[2]);
412 fvsum(v1, norm[3], vc1, -1.0);
413 pvect(v1);
414 printf("\n%s ", texname);
415 }
416 printf("polygon %s.%d\n", surfname, ++nout);
417 printf("0\n0\n9\n");
418 pvect(p0->p);
419 pvect(p1->p);
420 pvect(p2->p);
421 }
422 if (ok2) {
423 printf("\n%s ", modname);
424 if (axis != -1) {
425 printf("texfunc %s\n", texname);
426 printf(tsargs);
427 printf("0\n13\t%d\n", axis);
428 pvect(norm[0]);
429 pvect(norm[1]);
430 pvect(norm[2]);
431 fvsum(v2, norm[3], vc2, -1.0);
432 pvect(v2);
433 printf("\n%s ", texname);
434 }
435 printf("polygon %s.%d\n", surfname, ++nout);
436 printf("0\n0\n9\n");
437 pvect(p2->p);
438 pvect(p1->p);
439 pvect(p3->p);
440 }
441 }
442
443
444 void
445 comprow( /* compute row of values */
446 double s,
447 register POINT *row,
448 int siz
449 )
450 {
451 double st[2];
452 int end;
453 int checkvalid;
454 register int i;
455
456 if (smooth) {
457 i = -1; /* compute one past each end */
458 end = siz+1;
459 } else {
460 if (s < -FTINY || s > 1.0+FTINY)
461 return;
462 i = 0;
463 end = siz;
464 }
465 st[0] = s;
466 checkvalid = (fundefined(VNAME) == 2);
467 while (i <= end) {
468 st[1] = (double)i/siz;
469 if (checkvalid && funvalue(VNAME, 2, st) <= 0.0) {
470 row[i].valid = 0;
471 row[i].p[0] = row[i].p[1] = row[i].p[2] = 0.0;
472 row[i].uv[0] = row[i].uv[1] = 0.0;
473 } else {
474 row[i].valid = 1;
475 row[i].p[0] = funvalue(XNAME, 2, st);
476 row[i].p[1] = funvalue(YNAME, 2, st);
477 row[i].p[2] = funvalue(ZNAME, 2, st);
478 row[i].uv[0] = st[0];
479 row[i].uv[1] = st[1];
480 }
481 i++;
482 }
483 }
484
485
486 void
487 compnorms( /* compute row of averaged normals */
488 register POINT *r0,
489 register POINT *r1,
490 register POINT *r2,
491 int siz
492 )
493 {
494 FVECT v1, v2;
495
496 if (!smooth) /* not needed if no smoothing */
497 return;
498 /* compute row 1 normals */
499 while (siz-- >= 0) {
500 if (!r1[0].valid)
501 continue;
502 if (!r0[0].valid) {
503 if (!r2[0].valid) {
504 r1[0].n[0] = r1[0].n[1] = r1[0].n[2] = 0.0;
505 continue;
506 }
507 fvsum(v1, r2[0].p, r1[0].p, -1.0);
508 } else if (!r2[0].valid)
509 fvsum(v1, r1[0].p, r0[0].p, -1.0);
510 else
511 fvsum(v1, r2[0].p, r0[0].p, -1.0);
512 if (!r1[-1].valid) {
513 if (!r1[1].valid) {
514 r1[0].n[0] = r1[0].n[1] = r1[0].n[2] = 0.0;
515 continue;
516 }
517 fvsum(v2, r1[1].p, r1[0].p, -1.0);
518 } else if (!r1[1].valid)
519 fvsum(v2, r1[0].p, r1[-1].p, -1.0);
520 else
521 fvsum(v2, r1[1].p, r1[-1].p, -1.0);
522 fcross(r1[0].n, v1, v2);
523 normalize(r1[0].n);
524 r0++; r1++; r2++;
525 }
526 }
527
528
529 int
530 norminterp( /* compute normal interpolation */
531 register FVECT resmat[4],
532 POINT *p0,
533 POINT *p1,
534 POINT *p2,
535 POINT *p3
536 )
537 {
538 #define u ((ax+1)%3)
539 #define v ((ax+2)%3)
540
541 register int ax;
542 MAT4 eqnmat;
543 FVECT v1;
544 register int i, j;
545
546 if (!smooth) /* no interpolation if no smoothing */
547 return(-1);
548 /* find dominant axis */
549 VCOPY(v1, p0->n);
550 fvsum(v1, v1, p1->n, 1.0);
551 fvsum(v1, v1, p2->n, 1.0);
552 fvsum(v1, v1, p3->n, 1.0);
553 ax = ABS(v1[0]) > ABS(v1[1]) ? 0 : 1;
554 ax = ABS(v1[ax]) > ABS(v1[2]) ? ax : 2;
555 /* assign equation matrix */
556 eqnmat[0][0] = p0->p[u]*p0->p[v];
557 eqnmat[0][1] = p0->p[u];
558 eqnmat[0][2] = p0->p[v];
559 eqnmat[0][3] = 1.0;
560 eqnmat[1][0] = p1->p[u]*p1->p[v];
561 eqnmat[1][1] = p1->p[u];
562 eqnmat[1][2] = p1->p[v];
563 eqnmat[1][3] = 1.0;
564 eqnmat[2][0] = p2->p[u]*p2->p[v];
565 eqnmat[2][1] = p2->p[u];
566 eqnmat[2][2] = p2->p[v];
567 eqnmat[2][3] = 1.0;
568 eqnmat[3][0] = p3->p[u]*p3->p[v];
569 eqnmat[3][1] = p3->p[u];
570 eqnmat[3][2] = p3->p[v];
571 eqnmat[3][3] = 1.0;
572 /* invert matrix (solve system) */
573 if (!invmat4(eqnmat, eqnmat))
574 return(-1); /* no solution */
575 /* compute result matrix */
576 for (j = 0; j < 4; j++)
577 for (i = 0; i < 3; i++)
578 resmat[j][i] = eqnmat[j][0]*p0->n[i] +
579 eqnmat[j][1]*p1->n[i] +
580 eqnmat[j][2]*p2->n[i] +
581 eqnmat[j][3]*p3->n[i];
582 return(ax);
583
584 #undef u
585 #undef v
586 }
587
588
589 void
590 eputs(msg)
591 char *msg;
592 {
593 fputs(msg, stderr);
594 }
595
596
597 void
598 wputs(msg)
599 char *msg;
600 {
601 eputs(msg);
602 }
603
604
605 void
606 quit(code)
607 int code;
608 {
609 exit(code);
610 }
611
612
613 void
614 printhead( /* print command header */
615 register int ac,
616 register char **av
617 )
618 {
619 putchar('#');
620 while (ac--) {
621 putchar(' ');
622 fputs(*av++, stdout);
623 }
624 putchar('\n');
625 }
626
627
628 double
629 l_hermite(char *nm)
630 {
631 double t;
632
633 t = argument(5);
634 return( argument(1)*((2.0*t-3.0)*t*t+1.0) +
635 argument(2)*(-2.0*t+3.0)*t*t +
636 argument(3)*((t-2.0)*t+1.0)*t +
637 argument(4)*(t-1.0)*t*t );
638 }
639
640
641 double
642 l_bezier(char *nm)
643 {
644 double t;
645
646 t = argument(5);
647 return( argument(1) * (1.+t*(-3.+t*(3.-t))) +
648 argument(2) * 3.*t*(1.+t*(-2.+t)) +
649 argument(3) * 3.*t*t*(1.-t) +
650 argument(4) * t*t*t );
651 }
652
653
654 double
655 l_bspline(char *nm)
656 {
657 double t;
658
659 t = argument(5);
660 return( argument(1) * (1./6.+t*(-1./2.+t*(1./2.-1./6.*t))) +
661 argument(2) * (2./3.+t*t*(-1.+1./2.*t)) +
662 argument(3) * (1./6.+t*(1./2.+t*(1./2.-1./2.*t))) +
663 argument(4) * (1./6.*t*t*t) );
664 }