ViewVC Help
View File | Revision Log | Show Annotations | Download File | Root Listing
root/radiance/ray/src/gen/gensurf.c
Revision: 2.8
Committed: Tue Mar 11 22:57:45 2003 UTC (21 years ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.7: +3 -1 lines
Log Message:
Bug fix in output of .OBJ usemtl statement

File Contents

# User Rev Content
1 greg 1.1 #ifndef lint
2 greg 2.7 static const char RCSid[] = "$Id$";
3 greg 1.1 #endif
4 greg 1.2 /*
5 greg 1.1 * 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 greg 2.6 *
15     * 4/16/02 Added conditional vertex output
16 greg 1.1 */
17    
18 greg 1.5 #include "standard.h"
19 greg 1.1
20 greg 2.6 char XNAME[] = "X`SYS"; /* x function name */
21     char YNAME[] = "Y`SYS"; /* y function name */
22     char ZNAME[] = "Z`SYS"; /* z function name */
23    
24     char VNAME[] = "valid"; /* valid vertex name */
25 greg 1.1
26 greg 1.4 #define ABS(x) ((x)>=0 ? (x) : -(x))
27    
28 greg 1.3 #define pvect(p) printf(vformat, (p)[0], (p)[1], (p)[2])
29 greg 1.1
30     char vformat[] = "%15.9g %15.9g %15.9g\n";
31 greg 1.3 char tsargs[] = "4 surf_dx surf_dy surf_dz surf.cal\n";
32     char texname[] = "Phong";
33 greg 1.1
34 greg 1.3 int smooth = 0; /* apply smoothing? */
35 greg 2.7 int objout = 0; /* output .OBJ format? */
36 greg 1.1
37 greg 1.3 char *modname, *surfname;
38 greg 1.1
39 greg 2.2 /* recorded data flags */
40     #define HASBORDER 01
41     #define TRIPLETS 02
42     /* a data structure */
43     struct {
44     int flags; /* data type */
45     short m, n; /* number of s and t values */
46     FLOAT *data; /* the data itself, s major sort */
47     } datarec; /* our recorded data */
48 greg 1.3
49 greg 2.2 double l_hermite(), l_bezier(), l_bspline(), l_dataval();
50     extern double funvalue(), argument();
51    
52 greg 1.3 typedef struct {
53 greg 2.7 int valid; /* point is valid (vertex number) */
54 greg 1.3 FVECT p; /* vertex position */
55     FVECT n; /* average normal */
56 greg 2.7 FLOAT uv[2]; /* (u,v) position */
57 greg 1.3 } POINT;
58    
59    
60 greg 1.1 main(argc, argv)
61     int argc;
62     char *argv[];
63     {
64 greg 1.9 extern long eclock;
65 greg 1.3 POINT *row0, *row1, *row2, *rp;
66 greg 1.1 int i, j, m, n;
67     char stmp[256];
68    
69 greg 1.13 varset("PI", ':', PI);
70 greg 1.14 funset("hermite", 5, ':', l_hermite);
71     funset("bezier", 5, ':', l_bezier);
72     funset("bspline", 5, ':', l_bspline);
73 greg 1.1
74     if (argc < 8)
75     goto userror;
76    
77     for (i = 8; i < argc; i++)
78     if (!strcmp(argv[i], "-e"))
79 greg 1.10 scompile(argv[++i], NULL, 0);
80 greg 1.1 else if (!strcmp(argv[i], "-f"))
81     fcompile(argv[++i]);
82 greg 1.3 else if (!strcmp(argv[i], "-s"))
83     smooth++;
84 greg 2.7 else if (!strcmp(argv[i], "-o"))
85     objout++;
86 greg 1.1 else
87     goto userror;
88    
89 greg 1.3 modname = argv[1];
90     surfname = argv[2];
91 greg 1.1 m = atoi(argv[6]);
92     n = atoi(argv[7]);
93     if (m <= 0 || n <= 0)
94     goto userror;
95 greg 2.2 if (!strcmp(argv[5], "-") || access(argv[5], 4) == 0) { /* file? */
96     funset(ZNAME, 2, ':', l_dataval);
97     if (!strcmp(argv[5],argv[3]) && !strcmp(argv[5],argv[4])) {
98     loaddata(argv[5], m, n, 3);
99     funset(XNAME, 2, ':', l_dataval);
100     funset(YNAME, 2, ':', l_dataval);
101     } else {
102     loaddata(argv[5], m, n, 1);
103     sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
104     scompile(stmp, NULL, 0);
105     sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
106     scompile(stmp, NULL, 0);
107     }
108     } else {
109     sprintf(stmp, "%s(s,t)=%s;", XNAME, argv[3]);
110     scompile(stmp, NULL, 0);
111     sprintf(stmp, "%s(s,t)=%s;", YNAME, argv[4]);
112     scompile(stmp, NULL, 0);
113     sprintf(stmp, "%s(s,t)=%s;", ZNAME, argv[5]);
114     scompile(stmp, NULL, 0);
115     }
116 greg 1.4 row0 = (POINT *)malloc((n+3)*sizeof(POINT));
117     row1 = (POINT *)malloc((n+3)*sizeof(POINT));
118     row2 = (POINT *)malloc((n+3)*sizeof(POINT));
119 greg 1.3 if (row0 == NULL || row1 == NULL || row2 == NULL) {
120 greg 1.1 fprintf(stderr, "%s: out of memory\n", argv[0]);
121     quit(1);
122     }
123 greg 1.4 row0++; row1++; row2++;
124 greg 1.3 /* print header */
125 greg 1.1 printhead(argc, argv);
126 greg 1.9 eclock = 0;
127 greg 1.4 /* initialize */
128     comprow(-1.0/m, row0, n);
129 greg 1.3 comprow(0.0, row1, n);
130     comprow(1.0/m, row2, n);
131 greg 1.4 compnorms(row0, row1, row2, n);
132 greg 2.8 if (objout) {
133     printf("\nusemtl %s\n\n", modname);
134 greg 2.7 putobjrow(row1, n);
135 greg 2.8 }
136 greg 1.3 /* for each row */
137 greg 1.1 for (i = 0; i < m; i++) {
138     /* compute next row */
139 greg 1.3 rp = row0;
140 greg 1.1 row0 = row1;
141 greg 1.3 row1 = row2;
142     row2 = rp;
143 greg 1.4 comprow((double)(i+2)/m, row2, n);
144     compnorms(row0, row1, row2, n);
145 greg 2.7 if (objout)
146     putobjrow(row1, n);
147 greg 1.1
148     for (j = 0; j < n; j++) {
149 greg 2.6 int orient = (j & 1);
150 greg 1.3 /* put polygons */
151 greg 2.7 if (!(row0[j].valid && row1[j+1].valid))
152 greg 2.6 orient = 1;
153 greg 2.7 else if (!(row1[j].valid && row0[j+1].valid))
154 greg 2.6 orient = 0;
155     if (orient)
156 greg 1.3 putsquare(&row0[j], &row1[j],
157     &row0[j+1], &row1[j+1]);
158     else
159     putsquare(&row1[j], &row1[j+1],
160     &row0[j], &row0[j+1]);
161 greg 1.1 }
162     }
163    
164     quit(0);
165    
166     userror:
167     fprintf(stderr, "Usage: %s material name ", argv[0]);
168 greg 1.3 fprintf(stderr, "x(s,t) y(s,t) z(s,t) m n [-s][-e expr][-f file]\n");
169 greg 1.1 quit(1);
170 greg 2.2 }
171    
172    
173     loaddata(file, m, n, pointsize) /* load point data from file */
174     char *file;
175     int m, n;
176     int pointsize;
177     {
178     FILE *fp;
179     char word[64];
180     register int size;
181     register FLOAT *dp;
182    
183     datarec.flags = HASBORDER; /* assume border values */
184 greg 2.3 datarec.m = m+1;
185     datarec.n = n+1;
186     size = datarec.m*datarec.n*pointsize;
187 greg 2.2 if (pointsize == 3)
188     datarec.flags |= TRIPLETS;
189     dp = (FLOAT *)malloc(size*sizeof(FLOAT));
190     if ((datarec.data = dp) == NULL) {
191     fputs("Out of memory\n", stderr);
192     exit(1);
193     }
194     if (!strcmp(file, "-")) {
195     file = "<stdin>";
196     fp = stdin;
197     } else if ((fp = fopen(file, "r")) == NULL) {
198     fputs(file, stderr);
199     fputs(": cannot open\n", stderr);
200     exit(1);
201     }
202     while (size > 0 && fgetword(word, sizeof(word), fp) != NULL) {
203     if (!isflt(word)) {
204     fprintf(stderr, "%s: garbled data value: %s\n",
205     file, word);
206     exit(1);
207     }
208     *dp++ = atof(word);
209     size--;
210     }
211     if (size == (m+n+1)*pointsize) { /* no border after all */
212     dp = (FLOAT *)realloc((char *)datarec.data,
213     m*n*pointsize*sizeof(FLOAT));
214     if (dp != NULL)
215     datarec.data = dp;
216     datarec.flags &= ~HASBORDER;
217 greg 2.3 datarec.m = m;
218     datarec.n = n;
219 greg 2.2 size = 0;
220     }
221 greg 2.3 if (datarec.m < 2 || datarec.n < 2 || size != 0 ||
222     fgetword(word, sizeof(word), fp) != NULL) {
223 greg 2.2 fputs(file, stderr);
224     fputs(": bad number of data points\n", stderr);
225     exit(1);
226     }
227     fclose(fp);
228     }
229    
230    
231     double
232     l_dataval(nam) /* return recorded data value */
233     char *nam;
234     {
235     double u, v;
236     register int i, j;
237     register FLOAT *dp;
238     double d00, d01, d10, d11;
239     /* compute coordinates */
240     u = argument(1); v = argument(2);
241     if (datarec.flags & HASBORDER) {
242 greg 2.3 i = u *= datarec.m-1;
243     j = v *= datarec.n-1;
244 greg 2.2 } else {
245 greg 2.3 i = u = u*datarec.m - .5;
246     j = v = v*datarec.n - .5;
247 greg 2.2 }
248     if (i < 0) i = 0;
249     else if (i > datarec.m-2) i = datarec.m-2;
250     if (j < 0) j = 0;
251     else if (j > datarec.n-2) j = datarec.n-2;
252     /* compute value */
253     if (datarec.flags & TRIPLETS) {
254 greg 2.3 dp = datarec.data + 3*(j*datarec.m + i);
255     if (nam == ZNAME)
256     dp += 2;
257     else if (nam == YNAME)
258 greg 2.2 dp++;
259     d00 = dp[0]; d01 = dp[3];
260 greg 2.3 dp += 3*datarec.m;
261 greg 2.2 d10 = dp[0]; d11 = dp[3];
262     } else {
263 greg 2.3 dp = datarec.data + j*datarec.m + i;
264 greg 2.2 d00 = dp[0]; d01 = dp[1];
265 greg 2.3 dp += datarec.m;
266 greg 2.2 d10 = dp[0]; d11 = dp[1];
267     }
268     /* bilinear interpolation */
269     return((j+1-v)*((i+1-u)*d00+(u-i)*d01)+(v-j)*((i+1-u)*d10+(u-i)*d11));
270 greg 1.1 }
271    
272    
273 greg 2.7 putobjrow(rp, n) /* output vertex row to .OBJ */
274     register POINT *rp;
275     int n;
276     {
277     static int nverts = 0;
278    
279     for ( ; n-- >= 0; rp++) {
280     if (!rp->valid)
281     continue;
282     fputs("v ", stdout);
283     printf(vformat, rp->p[0], rp->p[1], rp->p[2]);
284     if (smooth)
285     printf("\tvn %.9g %.9g %.9g\n",
286     rp->n[0], rp->n[1], rp->n[2]);
287     printf("\tvt %.9g %.9g\n", rp->uv[0], rp->uv[1]);
288     rp->valid = ++nverts;
289     }
290     }
291    
292    
293 greg 1.3 putsquare(p0, p1, p2, p3) /* put out a square */
294     POINT *p0, *p1, *p2, *p3;
295     {
296     static int nout = 0;
297     FVECT norm[4];
298     int axis;
299     FVECT v1, v2, vc1, vc2;
300     int ok1, ok2;
301     /* compute exact normals */
302 greg 2.7 ok1 = (p0->valid && p1->valid && p2->valid);
303 greg 2.6 if (ok1) {
304     fvsum(v1, p1->p, p0->p, -1.0);
305     fvsum(v2, p2->p, p0->p, -1.0);
306     fcross(vc1, v1, v2);
307     ok1 = (normalize(vc1) != 0.0);
308     }
309 greg 2.7 ok2 = (p1->valid && p2->valid && p3->valid);
310 greg 2.6 if (ok2) {
311     fvsum(v1, p2->p, p3->p, -1.0);
312     fvsum(v2, p1->p, p3->p, -1.0);
313     fcross(vc2, v1, v2);
314     ok2 = (normalize(vc2) != 0.0);
315     }
316 greg 1.3 if (!(ok1 | ok2))
317     return;
318 greg 2.7 if (objout) { /* output .OBJ faces */
319     int p0n=0, p1n=0, p2n=0, p3n=0;
320     if (smooth) {
321     p0n = p0->valid;
322     p1n = p1->valid;
323     p2n = p2->valid;
324     p3n = p3->valid;
325     }
326     if (ok1 & ok2 && fdot(vc1,vc2) >= 1.0-FTINY*FTINY) {
327     printf("f %d/%d/%d %d/%d/%d %d/%d/%d %d/%d/%d\n",
328     p0->valid, p0n, p0->valid,
329     p1->valid, p1n, p1->valid,
330     p3->valid, p3n, p3->valid,
331     p2->valid, p2n, p2->valid);
332     return;
333     }
334     if (ok1)
335     printf("f %d/%d/%d %d/%d/%d %d/%d/%d\n",
336     p0->valid, p0n, p0->valid,
337     p1->valid, p1n, p1->valid,
338     p2->valid, p2n, p2->valid);
339     if (ok2)
340     printf("f %d/%d/%d %d/%d/%d %d/%d/%d\n",
341     p2->valid, p2n, p2->valid,
342     p1->valid, p1n, p1->valid,
343     p3->valid, p3n, p3->valid);
344     return;
345     }
346 greg 1.3 /* compute normal interpolation */
347     axis = norminterp(norm, p0, p1, p2, p3);
348    
349     /* put out quadrilateral? */
350     if (ok1 & ok2 && fdot(vc1,vc2) >= 1.0-FTINY*FTINY) {
351     printf("\n%s ", modname);
352     if (axis != -1) {
353     printf("texfunc %s\n", texname);
354     printf(tsargs);
355     printf("0\n13\t%d\n", axis);
356     pvect(norm[0]);
357     pvect(norm[1]);
358     pvect(norm[2]);
359     fvsum(v1, norm[3], vc1, -0.5);
360     fvsum(v1, v1, vc2, -0.5);
361     pvect(v1);
362     printf("\n%s ", texname);
363     }
364     printf("polygon %s.%d\n", surfname, ++nout);
365     printf("0\n0\n12\n");
366     pvect(p0->p);
367     pvect(p1->p);
368     pvect(p3->p);
369     pvect(p2->p);
370     return;
371     }
372     /* put out triangles? */
373     if (ok1) {
374     printf("\n%s ", modname);
375     if (axis != -1) {
376     printf("texfunc %s\n", texname);
377     printf(tsargs);
378     printf("0\n13\t%d\n", axis);
379     pvect(norm[0]);
380     pvect(norm[1]);
381     pvect(norm[2]);
382     fvsum(v1, norm[3], vc1, -1.0);
383     pvect(v1);
384     printf("\n%s ", texname);
385     }
386     printf("polygon %s.%d\n", surfname, ++nout);
387     printf("0\n0\n9\n");
388     pvect(p0->p);
389     pvect(p1->p);
390     pvect(p2->p);
391     }
392     if (ok2) {
393     printf("\n%s ", modname);
394     if (axis != -1) {
395     printf("texfunc %s\n", texname);
396     printf(tsargs);
397     printf("0\n13\t%d\n", axis);
398     pvect(norm[0]);
399     pvect(norm[1]);
400     pvect(norm[2]);
401     fvsum(v2, norm[3], vc2, -1.0);
402     pvect(v2);
403     printf("\n%s ", texname);
404     }
405     printf("polygon %s.%d\n", surfname, ++nout);
406     printf("0\n0\n9\n");
407     pvect(p2->p);
408     pvect(p1->p);
409     pvect(p3->p);
410     }
411     }
412    
413    
414 greg 1.1 comprow(s, row, siz) /* compute row of values */
415     double s;
416 greg 1.3 register POINT *row;
417 greg 1.1 int siz;
418     {
419 greg 1.4 double st[2];
420 greg 1.8 int end;
421 greg 2.6 int checkvalid;
422 greg 1.4 register int i;
423 greg 1.8
424     if (smooth) {
425     i = -1; /* compute one past each end */
426     end = siz+1;
427     } else {
428     if (s < -FTINY || s > 1.0+FTINY)
429     return;
430     i = 0;
431     end = siz;
432     }
433 greg 1.1 st[0] = s;
434 greg 2.6 checkvalid = (fundefined(VNAME) == 2);
435 greg 1.8 while (i <= end) {
436 greg 1.4 st[1] = (double)i/siz;
437 greg 2.6 if (checkvalid && funvalue(VNAME, 2, st) <= 0.0) {
438     row[i].valid = 0;
439     row[i].p[0] = row[i].p[1] = row[i].p[2] = 0.0;
440 greg 2.7 row[i].uv[0] = row[i].uv[1] = 0.0;
441 greg 2.6 } else {
442     row[i].valid = 1;
443     row[i].p[0] = funvalue(XNAME, 2, st);
444     row[i].p[1] = funvalue(YNAME, 2, st);
445     row[i].p[2] = funvalue(ZNAME, 2, st);
446 greg 2.7 row[i].uv[0] = st[0];
447     row[i].uv[1] = st[1];
448 greg 2.6 }
449 greg 1.8 i++;
450 greg 1.1 }
451 greg 1.3 }
452    
453    
454     compnorms(r0, r1, r2, siz) /* compute row of averaged normals */
455     register POINT *r0, *r1, *r2;
456     int siz;
457     {
458 greg 1.11 FVECT v1, v2;
459 greg 1.3
460     if (!smooth) /* not needed if no smoothing */
461     return;
462 greg 2.6 /* compute row 1 normals */
463 greg 1.4 while (siz-- >= 0) {
464 greg 2.6 if (!r1[0].valid)
465     continue;
466     if (!r0[0].valid) {
467     if (!r2[0].valid) {
468     r1[0].n[0] = r1[0].n[1] = r1[0].n[2] = 0.0;
469     continue;
470     }
471     fvsum(v1, r2[0].p, r1[0].p, -1.0);
472     } else if (!r2[0].valid)
473     fvsum(v1, r1[0].p, r0[0].p, -1.0);
474     else
475     fvsum(v1, r2[0].p, r0[0].p, -1.0);
476     if (!r1[-1].valid) {
477     if (!r1[1].valid) {
478     r1[0].n[0] = r1[0].n[1] = r1[0].n[2] = 0.0;
479     continue;
480     }
481     fvsum(v2, r1[1].p, r1[0].p, -1.0);
482     } else if (!r1[1].valid)
483     fvsum(v2, r1[0].p, r1[-1].p, -1.0);
484     else
485     fvsum(v2, r1[1].p, r1[-1].p, -1.0);
486 greg 1.3 fcross(r1[0].n, v1, v2);
487     normalize(r1[0].n);
488     r0++; r1++; r2++;
489     }
490     }
491    
492    
493     int
494     norminterp(resmat, p0, p1, p2, p3) /* compute normal interpolation */
495     register FVECT resmat[4];
496     POINT *p0, *p1, *p2, *p3;
497     {
498     #define u ((ax+1)%3)
499     #define v ((ax+2)%3)
500    
501     register int ax;
502 greg 1.12 MAT4 eqnmat;
503 greg 1.3 FVECT v1;
504     register int i, j;
505    
506     if (!smooth) /* no interpolation if no smoothing */
507     return(-1);
508     /* find dominant axis */
509     VCOPY(v1, p0->n);
510     fvsum(v1, v1, p1->n, 1.0);
511     fvsum(v1, v1, p2->n, 1.0);
512     fvsum(v1, v1, p3->n, 1.0);
513 greg 1.4 ax = ABS(v1[0]) > ABS(v1[1]) ? 0 : 1;
514     ax = ABS(v1[ax]) > ABS(v1[2]) ? ax : 2;
515 greg 1.3 /* assign equation matrix */
516     eqnmat[0][0] = p0->p[u]*p0->p[v];
517     eqnmat[0][1] = p0->p[u];
518     eqnmat[0][2] = p0->p[v];
519     eqnmat[0][3] = 1.0;
520     eqnmat[1][0] = p1->p[u]*p1->p[v];
521     eqnmat[1][1] = p1->p[u];
522     eqnmat[1][2] = p1->p[v];
523     eqnmat[1][3] = 1.0;
524     eqnmat[2][0] = p2->p[u]*p2->p[v];
525     eqnmat[2][1] = p2->p[u];
526     eqnmat[2][2] = p2->p[v];
527     eqnmat[2][3] = 1.0;
528     eqnmat[3][0] = p3->p[u]*p3->p[v];
529     eqnmat[3][1] = p3->p[u];
530     eqnmat[3][2] = p3->p[v];
531     eqnmat[3][3] = 1.0;
532     /* invert matrix (solve system) */
533 greg 2.5 if (!invmat4(eqnmat, eqnmat))
534 greg 1.3 return(-1); /* no solution */
535     /* compute result matrix */
536     for (j = 0; j < 4; j++)
537     for (i = 0; i < 3; i++)
538 greg 1.4 resmat[j][i] = eqnmat[j][0]*p0->n[i] +
539     eqnmat[j][1]*p1->n[i] +
540     eqnmat[j][2]*p2->n[i] +
541     eqnmat[j][3]*p3->n[i];
542 greg 1.3 return(ax);
543    
544     #undef u
545     #undef v
546 greg 1.1 }
547    
548    
549 greg 2.6 void
550 greg 1.1 eputs(msg)
551     char *msg;
552     {
553     fputs(msg, stderr);
554     }
555    
556    
557 greg 2.6 void
558 greg 1.1 wputs(msg)
559     char *msg;
560     {
561     eputs(msg);
562     }
563    
564    
565 greg 2.6 void
566 greg 1.1 quit(code)
567 greg 2.4 int code;
568 greg 1.1 {
569     exit(code);
570     }
571    
572    
573     printhead(ac, av) /* print command header */
574     register int ac;
575     register char **av;
576     {
577     putchar('#');
578     while (ac--) {
579     putchar(' ');
580     fputs(*av++, stdout);
581     }
582     putchar('\n');
583     }
584    
585    
586     double
587     l_hermite()
588     {
589     double t;
590    
591     t = argument(5);
592     return( argument(1)*((2.0*t-3.0)*t*t+1.0) +
593     argument(2)*(-2.0*t+3.0)*t*t +
594     argument(3)*((t-2.0)*t+1.0)*t +
595     argument(4)*(t-1.0)*t*t );
596 greg 1.6 }
597    
598    
599     double
600     l_bezier()
601     {
602     double t;
603    
604     t = argument(5);
605     return( argument(1) * (1.+t*(-3.+t*(3.-t))) +
606     argument(2) * 3.*t*(1.+t*(-2.+t)) +
607     argument(3) * 3.*t*t*(1.-t) +
608     argument(4) * t*t*t );
609 greg 1.7 }
610    
611    
612     double
613     l_bspline()
614     {
615     double t;
616    
617     t = argument(5);
618     return( argument(1) * (1./6.+t*(-1./2.+t*(1./2.-1./6.*t))) +
619     argument(2) * (2./3.+t*t*(-1.+1./2.*t)) +
620     argument(3) * (1./6.+t*(1./2.+t*(1./2.-1./2.*t))) +
621     argument(4) * (1./6.*t*t*t) );
622 greg 1.1 }