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root/radiance/ray/src/gen/mkillum2.c
Revision: 2.39
Committed: Thu Dec 4 05:26:28 2014 UTC (9 years, 4 months ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.38: +5 -13 lines
Log Message:
Improved behavior of anisotropic reflections

File Contents

# Content
1 #ifndef lint
2 static const char RCSid[] = "$Id: mkillum2.c,v 2.38 2012/10/13 20:15:43 greg Exp $";
3 #endif
4 /*
5 * Routines to do the actual calculation for mkillum
6 */
7
8 #include <string.h>
9
10 #include "mkillum.h"
11 #include "face.h"
12 #include "cone.h"
13 #include "source.h"
14 #include "paths.h"
15
16 #ifndef NBSDFSAMPS
17 #define NBSDFSAMPS 256 /* BSDF resampling count */
18 #endif
19
20 COLORV * distarr = NULL; /* distribution array */
21 int distsiz = 0;
22
23
24 void
25 newdist( /* allocate & clear distribution array */
26 int siz
27 )
28 {
29 if (siz <= 0) {
30 if (distsiz > 0)
31 free(distarr);
32 distarr = NULL;
33 distsiz = 0;
34 return;
35 }
36 if (distsiz < siz) {
37 if (distsiz > 0)
38 free(distarr);
39 distarr = (COLORV *)malloc(sizeof(COLOR)*siz);
40 if (distarr == NULL)
41 error(SYSTEM, "out of memory in newdist");
42 distsiz = siz;
43 }
44 memset(distarr, '\0', sizeof(COLOR)*siz);
45 }
46
47
48 int
49 process_ray( /* process a ray result or report error */
50 RAY *r,
51 int rv
52 )
53 {
54 COLORV *colp;
55
56 if (rv == 0) /* no result ready */
57 return(0);
58 if (rv < 0)
59 error(USER, "ray tracing process died");
60 if (r->rno >= distsiz)
61 error(INTERNAL, "bad returned index in process_ray");
62 multcolor(r->rcol, r->rcoef); /* in case it's a source ray */
63 colp = &distarr[r->rno * 3];
64 addcolor(colp, r->rcol);
65 return(1);
66 }
67
68
69 void
70 raysamp( /* queue a ray sample */
71 int ndx,
72 FVECT org,
73 FVECT dir
74 )
75 {
76 RAY myRay;
77 int rv;
78
79 if ((ndx < 0) | (ndx >= distsiz))
80 error(INTERNAL, "bad index in raysamp");
81 VCOPY(myRay.rorg, org);
82 VCOPY(myRay.rdir, dir);
83 myRay.rmax = .0;
84 rayorigin(&myRay, PRIMARY|SPECULAR, NULL, NULL);
85 myRay.rno = ndx;
86 /* queue ray, check result */
87 process_ray(&myRay, ray_pqueue(&myRay));
88 }
89
90
91 void
92 srcsamps( /* sample sources from this surface position */
93 struct illum_args *il,
94 FVECT org,
95 FVECT nrm,
96 MAT4 ixfm
97 )
98 {
99 int nalt=1, nazi=1;
100 SRCINDEX si;
101 RAY sr;
102 FVECT v;
103 double d;
104 int i, j;
105 /* get sampling density */
106 if (il->sampdens > 0) {
107 i = PI * il->sampdens;
108 nalt = sqrt(i/PI) + .5;
109 nazi = PI*nalt + .5;
110 }
111 initsrcindex(&si); /* loop over (sub)sources */
112 for ( ; ; ) {
113 VCOPY(sr.rorg, org); /* pick side to shoot from */
114 d = 5.*FTINY;
115 VSUM(sr.rorg, sr.rorg, nrm, d);
116 samplendx++; /* increment sample counter */
117 if (!srcray(&sr, NULL, &si))
118 break; /* end of sources */
119 /* index direction */
120 if (ixfm != NULL)
121 multv3(v, sr.rdir, ixfm);
122 else
123 VCOPY(v, sr.rdir);
124 if (v[2] >= -FTINY)
125 continue; /* only sample transmission */
126 v[0] = -v[0]; v[1] = -v[1]; v[2] = -v[2];
127 sr.rno = flatindex(v, nalt, nazi);
128 d = nalt*nazi*(1./PI) * v[2];
129 d *= si.dom; /* solid angle correction */
130 scalecolor(sr.rcoef, d);
131 process_ray(&sr, ray_pqueue(&sr));
132 }
133 }
134
135
136 void
137 rayclean() /* finish all pending rays */
138 {
139 RAY myRay;
140
141 while (process_ray(&myRay, ray_presult(&myRay, 0)))
142 ;
143 }
144
145
146 static void
147 mkaxes( /* compute u and v to go with n */
148 FVECT u,
149 FVECT v,
150 FVECT n
151 )
152 {
153 getperpendicular(u, n);
154 fcross(v, n, u);
155 }
156
157
158 static void
159 rounddir( /* compute uniform spherical direction */
160 FVECT dv,
161 double alt,
162 double azi
163 )
164 {
165 double d1, d2;
166
167 dv[2] = 1. - 2.*alt;
168 d1 = sqrt(1. - dv[2]*dv[2]);
169 d2 = 2.*PI * azi;
170 dv[0] = d1*cos(d2);
171 dv[1] = d1*sin(d2);
172 }
173
174
175 void
176 flatdir( /* compute uniform hemispherical direction */
177 FVECT dv,
178 double alt,
179 double azi
180 )
181 {
182 double d1, d2;
183
184 d1 = sqrt(alt);
185 d2 = 2.*PI * azi;
186 dv[0] = d1*cos(d2);
187 dv[1] = d1*sin(d2);
188 dv[2] = sqrt(1. - alt);
189 }
190
191
192 int
193 flatindex( /* compute index for hemispherical direction */
194 FVECT dv,
195 int nalt,
196 int nazi
197 )
198 {
199 double d;
200 int i, j;
201
202 d = 1.0 - dv[2]*dv[2];
203 i = d*nalt;
204 d = atan2(dv[1], dv[0]) * (0.5/PI);
205 if (d < 0.0) d += 1.0;
206 j = d*nazi + 0.5;
207 if (j >= nazi) j = 0;
208 return(i*nazi + j);
209 }
210
211
212 int
213 my_default( /* default illum action */
214 OBJREC *ob,
215 struct illum_args *il,
216 char *nm
217 )
218 {
219 sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"",
220 nm, ofun[ob->otype].funame, ob->oname);
221 error(WARNING, errmsg);
222 printobj(il->altmat, ob);
223 return(1);
224 }
225
226
227 int
228 my_face( /* make an illum face */
229 OBJREC *ob,
230 struct illum_args *il,
231 char *nm
232 )
233 {
234 int dim[2];
235 int n, nalt, nazi, alti;
236 double sp[2], r1, r2;
237 int h;
238 FVECT dn, org, dir;
239 FVECT u, v;
240 double ur[2], vr[2];
241 MAT4 xfm;
242 char xfrot[64];
243 int nallow;
244 FACE *fa;
245 int i, j;
246 /* get/check arguments */
247 fa = getface(ob);
248 if (fa->area == 0.0) {
249 freeface(ob);
250 return(my_default(ob, il, nm));
251 }
252 /* set up sampling */
253 if (il->sampdens <= 0) {
254 nalt = nazi = 1; /* diffuse assumption */
255 } else {
256 n = PI * il->sampdens;
257 nalt = sqrt(n/PI) + .5;
258 nazi = PI*nalt + .5;
259 }
260 n = nazi*nalt;
261 newdist(n);
262 /* take first edge >= sqrt(area) */
263 for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) {
264 u[0] = VERTEX(fa,i)[0] - VERTEX(fa,j)[0];
265 u[1] = VERTEX(fa,i)[1] - VERTEX(fa,j)[1];
266 u[2] = VERTEX(fa,i)[2] - VERTEX(fa,j)[2];
267 if ((r1 = DOT(u,u)) >= fa->area-FTINY)
268 break;
269 }
270 if (i < fa->nv) { /* got one! -- let's align our axes */
271 r2 = 1.0/sqrt(r1);
272 u[0] *= r2; u[1] *= r2; u[2] *= r2;
273 fcross(v, fa->norm, u);
274 } else /* oh well, we'll just have to wing it */
275 mkaxes(u, v, fa->norm);
276 /* now, find limits in (u,v) coordinates */
277 ur[0] = vr[0] = FHUGE;
278 ur[1] = vr[1] = -FHUGE;
279 for (i = 0; i < fa->nv; i++) {
280 r1 = DOT(VERTEX(fa,i),u);
281 if (r1 < ur[0]) ur[0] = r1;
282 if (r1 > ur[1]) ur[1] = r1;
283 r2 = DOT(VERTEX(fa,i),v);
284 if (r2 < vr[0]) vr[0] = r2;
285 if (r2 > vr[1]) vr[1] = r2;
286 }
287 dim[0] = random();
288 /* sample polygon */
289 nallow = 5*n*il->nsamps;
290 for (dim[1] = 0; dim[1] < n; dim[1]++)
291 for (i = 0; i < il->nsamps; i++) {
292 /* randomize direction */
293 h = ilhash(dim, 2) + i;
294 multisamp(sp, 2, urand(h));
295 alti = dim[1]/nazi;
296 r1 = (alti + sp[0])/nalt;
297 r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
298 flatdir(dn, r1, r2);
299 for (j = 0; j < 3; j++)
300 dir[j] = -dn[0]*u[j] - dn[1]*v[j] -
301 dn[2]*fa->norm[j];
302 /* randomize location */
303 do {
304 multisamp(sp, 2, urand(h+4862+nallow));
305 r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
306 r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
307 for (j = 0; j < 3; j++)
308 org[j] = r1*u[j] + r2*v[j]
309 + fa->offset*fa->norm[j];
310 } while (!inface(org, fa) && nallow-- > 0);
311 if (nallow < 0) {
312 objerror(ob, WARNING, "bad aspect");
313 rayclean();
314 freeface(ob);
315 return(my_default(ob, il, nm));
316 }
317 r1 = 5.*FTINY;
318 for (j = 0; j < 3; j++)
319 org[j] += r1*fa->norm[j];
320 /* send sample */
321 raysamp(dim[1], org, dir);
322 }
323 /* add in direct component? */
324 if (il->flags & IL_LIGHT) {
325 MAT4 ixfm;
326 for (i = 3; i--; ) {
327 ixfm[i][0] = u[i];
328 ixfm[i][1] = v[i];
329 ixfm[i][2] = fa->norm[i];
330 ixfm[i][3] = 0.;
331 }
332 ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.;
333 ixfm[3][3] = 1.;
334 dim[0] = random();
335 nallow = 10*il->nsamps;
336 for (i = 0; i < il->nsamps; i++) {
337 /* randomize location */
338 h = dim[0] + samplendx++;
339 do {
340 multisamp(sp, 2, urand(h+nallow));
341 r1 = ur[0] + (ur[1]-ur[0]) * sp[0];
342 r2 = vr[0] + (vr[1]-vr[0]) * sp[1];
343 for (j = 0; j < 3; j++)
344 org[j] = r1*u[j] + r2*v[j]
345 + fa->offset*fa->norm[j];
346 } while (!inface(org, fa) && nallow-- > 0);
347 if (nallow < 0) {
348 objerror(ob, WARNING, "bad aspect");
349 rayclean();
350 freeface(ob);
351 return(my_default(ob, il, nm));
352 }
353 /* sample source rays */
354 srcsamps(il, org, fa->norm, ixfm);
355 }
356 }
357 /* wait for all rays to finish */
358 rayclean();
359 /* write out the face and its distribution */
360 if (average(il, distarr, n)) {
361 if (il->sampdens > 0)
362 flatout(il, distarr, nalt, nazi, u, v, fa->norm);
363 illumout(il, ob);
364 } else
365 printobj(il->altmat, ob);
366 /* clean up */
367 freeface(ob);
368 return(0);
369 }
370
371
372 int
373 my_sphere( /* make an illum sphere */
374 OBJREC *ob,
375 struct illum_args *il,
376 char *nm
377 )
378 {
379 int dim[3];
380 int n, nalt, nazi;
381 double sp[4], r1, r2, r3;
382 FVECT org, dir;
383 FVECT u, v;
384 int i, j;
385 /* check arguments */
386 if (ob->oargs.nfargs != 4)
387 objerror(ob, USER, "bad # of arguments");
388 /* set up sampling */
389 if (il->sampdens <= 0)
390 nalt = nazi = 1;
391 else {
392 n = 4.*PI * il->sampdens;
393 nalt = sqrt(2./PI*n) + .5;
394 nazi = PI/2.*nalt + .5;
395 }
396 n = nalt*nazi;
397 newdist(n);
398 dim[0] = random();
399 /* sample sphere */
400 for (dim[1] = 0; dim[1] < nalt; dim[1]++)
401 for (dim[2] = 0; dim[2] < nazi; dim[2]++)
402 for (i = 0; i < il->nsamps; i++) {
403 /* next sample point */
404 multisamp(sp, 4, urand(ilhash(dim,3)+i));
405 /* random direction */
406 r1 = (dim[1] + sp[0])/nalt;
407 r2 = (dim[2] + sp[1] - .5)/nazi;
408 rounddir(dir, r1, r2);
409 /* random location */
410 mkaxes(u, v, dir); /* yuck! */
411 r3 = sqrt(sp[2]);
412 r2 = 2.*PI*sp[3];
413 r1 = r3*ob->oargs.farg[3]*cos(r2);
414 r2 = r3*ob->oargs.farg[3]*sin(r2);
415 r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3);
416 for (j = 0; j < 3; j++) {
417 org[j] = ob->oargs.farg[j] + r1*u[j] + r2*v[j] +
418 r3*dir[j];
419 dir[j] = -dir[j];
420 }
421 /* send sample */
422 raysamp(dim[1]*nazi+dim[2], org, dir);
423 }
424 /* wait for all rays to finish */
425 rayclean();
426 /* write out the sphere and its distribution */
427 if (average(il, distarr, n)) {
428 if (il->sampdens > 0)
429 roundout(il, distarr, nalt, nazi);
430 else
431 objerror(ob, WARNING, "diffuse distribution");
432 illumout(il, ob);
433 } else
434 printobj(il->altmat, ob);
435 /* clean up */
436 return(1);
437 }
438
439
440 int
441 my_ring( /* make an illum ring */
442 OBJREC *ob,
443 struct illum_args *il,
444 char *nm
445 )
446 {
447 int dim[2];
448 int n, nalt, nazi, alti;
449 double sp[2], r1, r2, r3;
450 int h;
451 FVECT dn, org, dir;
452 FVECT u, v;
453 MAT4 xfm;
454 CONE *co;
455 int i, j;
456 /* get/check arguments */
457 co = getcone(ob, 0);
458 /* set up sampling */
459 if (il->sampdens <= 0) {
460 nalt = nazi = 1; /* diffuse assumption */
461 } else {
462 n = PI * il->sampdens;
463 nalt = sqrt(n/PI) + .5;
464 nazi = PI*nalt + .5;
465 }
466 n = nazi*nalt;
467 newdist(n);
468 mkaxes(u, v, co->ad);
469 dim[0] = random();
470 /* sample disk */
471 for (dim[1] = 0; dim[1] < n; dim[1]++)
472 for (i = 0; i < il->nsamps; i++) {
473 /* next sample point */
474 h = ilhash(dim,2) + i;
475 /* randomize direction */
476 multisamp(sp, 2, urand(h));
477 alti = dim[1]/nazi;
478 r1 = (alti + sp[0])/nalt;
479 r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi;
480 flatdir(dn, r1, r2);
481 for (j = 0; j < 3; j++)
482 dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j];
483 /* randomize location */
484 multisamp(sp, 2, urand(h+8371));
485 r3 = sqrt(CO_R0(co)*CO_R0(co) +
486 sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
487 r2 = 2.*PI*sp[1];
488 r1 = r3*cos(r2);
489 r2 = r3*sin(r2);
490 r3 = 5.*FTINY;
491 for (j = 0; j < 3; j++)
492 org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] +
493 r3*co->ad[j];
494 /* send sample */
495 raysamp(dim[1], org, dir);
496 }
497 /* add in direct component? */
498 if (il->flags & IL_LIGHT) {
499 MAT4 ixfm;
500 for (i = 3; i--; ) {
501 ixfm[i][0] = u[i];
502 ixfm[i][1] = v[i];
503 ixfm[i][2] = co->ad[i];
504 ixfm[i][3] = 0.;
505 }
506 ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.;
507 ixfm[3][3] = 1.;
508 dim[0] = random();
509 for (i = 0; i < il->nsamps; i++) {
510 /* randomize location */
511 h = dim[0] + samplendx++;
512 multisamp(sp, 2, urand(h));
513 r3 = sqrt(CO_R0(co)*CO_R0(co) +
514 sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co)));
515 r2 = 2.*PI*sp[1];
516 r1 = r3*cos(r2);
517 r2 = r3*sin(r2);
518 for (j = 0; j < 3; j++)
519 org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j];
520 /* sample source rays */
521 srcsamps(il, org, co->ad, ixfm);
522 }
523 }
524 /* wait for all rays to finish */
525 rayclean();
526 /* write out the ring and its distribution */
527 if (average(il, distarr, n)) {
528 if (il->sampdens > 0)
529 flatout(il, distarr, nalt, nazi, u, v, co->ad);
530 illumout(il, ob);
531 } else
532 printobj(il->altmat, ob);
533 /* clean up */
534 freecone(ob);
535 return(1);
536 }