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#ifndef lint |
2 |
static const char RCSid[] = "$Id: pmap.c,v 2.16 2018/11/21 19:33:30 rschregle Exp $"; |
3 |
#endif |
4 |
|
5 |
|
6 |
/* |
7 |
====================================================================== |
8 |
Photon map main module |
9 |
|
10 |
Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) |
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(c) Fraunhofer Institute for Solar Energy Systems, |
12 |
(c) Lucerne University of Applied Sciences and Arts, |
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supported by the Swiss National Science Foundation (SNSF, #147053) |
14 |
====================================================================== |
15 |
|
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$Id: pmap.c,v 2.16 2018/11/21 19:33:30 rschregle Exp $ |
17 |
*/ |
18 |
|
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|
20 |
#include "pmap.h" |
21 |
#include "pmapmat.h" |
22 |
#include "pmapsrc.h" |
23 |
#include "pmaprand.h" |
24 |
#include "pmapio.h" |
25 |
#include "pmapbias.h" |
26 |
#include "pmapdiag.h" |
27 |
#include "otypes.h" |
28 |
#include <time.h> |
29 |
#if NIX |
30 |
#include <sys/stat.h> |
31 |
#include <sys/mman.h> |
32 |
#include <sys/wait.h> |
33 |
#endif |
34 |
|
35 |
|
36 |
void savePmaps (const PhotonMap **pmaps, int argc, char **argv) |
37 |
{ |
38 |
unsigned t; |
39 |
|
40 |
for (t = 0; t < NUM_PMAP_TYPES; t++) { |
41 |
if (pmaps [t]) |
42 |
savePhotonMap(pmaps [t], pmaps [t] -> fileName, argc, argv); |
43 |
} |
44 |
} |
45 |
|
46 |
|
47 |
|
48 |
static int photonParticipate (RAY *ray) |
49 |
/* Trace photon through participating medium. Returns 1 if passed through, |
50 |
or 0 if absorbed and $*%&ed. Analogon to rayparticipate(). */ |
51 |
{ |
52 |
int i; |
53 |
RREAL xi1, cosTheta, phi, du, dv; |
54 |
const float cext = colorAvg(ray -> cext), |
55 |
albedo = colorAvg(ray -> albedo), |
56 |
gecc = ray -> gecc, gecc2 = sqr(gecc); |
57 |
FVECT u, v; |
58 |
COLOR cvext; |
59 |
|
60 |
/* Mean free distance until interaction with medium */ |
61 |
ray -> rmax = -log(pmapRandom(mediumState)) / cext; |
62 |
|
63 |
while (!localhit(ray, &thescene)) { |
64 |
if (!incube(&thescene, ray -> rop)) { |
65 |
/* Terminate photon if it has leaked from the scene */ |
66 |
#ifdef DEBUG_PMAP |
67 |
fprintf(stderr, |
68 |
"Volume photon leaked from scene at [%.3f %.3f %.3f]\n", |
69 |
ray -> rop [0], ray -> rop [1], ray -> rop [2]); |
70 |
#endif |
71 |
return 0; |
72 |
} |
73 |
|
74 |
setcolor(cvext, exp(-ray -> rmax * ray -> cext [0]), |
75 |
exp(-ray -> rmax * ray -> cext [1]), |
76 |
exp(-ray -> rmax * ray -> cext [2])); |
77 |
|
78 |
/* Modify ray color and normalise */ |
79 |
multcolor(ray -> rcol, cvext); |
80 |
colorNorm(ray -> rcol); |
81 |
VCOPY(ray -> rorg, ray -> rop); |
82 |
|
83 |
#if 0 |
84 |
if (albedo > FTINY && ray -> rlvl > 0) |
85 |
#else |
86 |
/* Store volume photons unconditionally in mist to also account for |
87 |
direct inscattering from sources */ |
88 |
if (albedo > FTINY) |
89 |
#endif |
90 |
/* Add to volume photon map */ |
91 |
newPhoton(volumePmap, ray); |
92 |
|
93 |
/* Absorbed? */ |
94 |
if (pmapRandom(rouletteState) > albedo) |
95 |
return 0; |
96 |
|
97 |
/* Colour bleeding without attenuation (?) */ |
98 |
multcolor(ray -> rcol, ray -> albedo); |
99 |
scalecolor(ray -> rcol, 1 / albedo); |
100 |
|
101 |
/* Scatter photon */ |
102 |
xi1 = pmapRandom(scatterState); |
103 |
cosTheta = ray -> gecc <= FTINY |
104 |
? 2 * xi1 - 1 |
105 |
: 0.5 / gecc * |
106 |
(1 + gecc2 - sqr((1 - gecc2) / |
107 |
(1 + gecc * (2 * xi1 - 1)))); |
108 |
|
109 |
phi = 2 * PI * pmapRandom(scatterState); |
110 |
du = dv = sqrt(1 - sqr(cosTheta)); /* sin(theta) */ |
111 |
du *= cos(phi); |
112 |
dv *= sin(phi); |
113 |
|
114 |
/* Get axes u & v perpendicular to photon direction */ |
115 |
i = 0; |
116 |
do { |
117 |
v [0] = v [1] = v [2] = 0; |
118 |
v [i++] = 1; |
119 |
fcross(u, v, ray -> rdir); |
120 |
} while (normalize(u) < FTINY); |
121 |
fcross(v, ray -> rdir, u); |
122 |
|
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for (i = 0; i < 3; i++) |
124 |
ray -> rdir [i] = du * u [i] + dv * v [i] + |
125 |
cosTheta * ray -> rdir [i]; |
126 |
|
127 |
ray -> rlvl++; |
128 |
ray -> rmax = -log(pmapRandom(mediumState)) / cext; |
129 |
} |
130 |
|
131 |
/* Passed through medium until intersecting local object */ |
132 |
setcolor(cvext, exp(-ray -> rot * ray -> cext [0]), |
133 |
exp(-ray -> rot * ray -> cext [1]), |
134 |
exp(-ray -> rot * ray -> cext [2])); |
135 |
|
136 |
/* Modify ray color and normalise */ |
137 |
multcolor(ray -> rcol, cvext); |
138 |
colorNorm(ray -> rcol); |
139 |
|
140 |
return 1; |
141 |
} |
142 |
|
143 |
|
144 |
|
145 |
void tracePhoton (RAY *ray) |
146 |
/* Follow photon as it bounces around... */ |
147 |
{ |
148 |
long mod; |
149 |
OBJREC *mat, *port = NULL; |
150 |
|
151 |
if (!ray -> parent) { |
152 |
/* !!! PHOTON PORT REJECTION SAMPLING HACK: get photon port for |
153 |
* !!! primary ray from ray -> ro, then reset the latter to NULL so |
154 |
* !!! as not to interfere with localhit() */ |
155 |
port = ray -> ro; |
156 |
ray -> ro = NULL; |
157 |
} |
158 |
|
159 |
if (ray -> rlvl > photonMaxBounce) { |
160 |
#ifdef PMAP_RUNAWAY_WARN |
161 |
error(WARNING, "runaway photon!"); |
162 |
#endif |
163 |
return; |
164 |
} |
165 |
|
166 |
if (colorAvg(ray -> cext) > FTINY && !photonParticipate(ray)) |
167 |
return; |
168 |
|
169 |
if (localhit(ray, &thescene)) { |
170 |
mod = ray -> ro -> omod; |
171 |
|
172 |
if (port && ray -> ro != port) { |
173 |
/* !!! PHOTON PORT REJECTION SAMPLING HACK !!! |
174 |
* Terminate photon if emitted from port without intersecting it; |
175 |
* this can happen when the port's partitions extend beyond its |
176 |
* actual geometry, e.g. with polygons. Since the total flux |
177 |
* relayed by the port is based on the (in this case) larger |
178 |
* partition area, it is overestimated; terminating these photons |
179 |
* constitutes rejection sampling and thereby compensates any bias |
180 |
* incurred by the overestimated flux. */ |
181 |
#ifdef PMAP_PORTREJECT_WARN |
182 |
sprintf(errmsg, "photon outside port %s", ray -> ro -> oname); |
183 |
error(WARNING, errmsg); |
184 |
#endif |
185 |
return; |
186 |
} |
187 |
|
188 |
if ((ray -> clipset && inset(ray -> clipset, mod)) || mod == OVOID) { |
189 |
/* Transfer ray if modifier is VOID or clipped within antimatta */ |
190 |
RAY tray; |
191 |
photonRay(ray, &tray, PMAP_XFER, NULL); |
192 |
tracePhoton(&tray); |
193 |
} |
194 |
else { |
195 |
/* Scatter for modifier material */ |
196 |
mat = objptr(mod); |
197 |
photonScatter [mat -> otype] (mat, ray); |
198 |
} |
199 |
} |
200 |
} |
201 |
|
202 |
|
203 |
|
204 |
static void preComputeGlobal (PhotonMap *pmap) |
205 |
/* Precompute irradiance from global photons for final gathering for |
206 |
a random subset of finalGather * pmap -> numPhotons photons, and builds |
207 |
the photon map, discarding the original photons. */ |
208 |
/* !!! NOTE: PRECOMPUTATION WITH OOC CURRENTLY WITHOUT CACHE !!! */ |
209 |
{ |
210 |
unsigned long i, numPreComp; |
211 |
unsigned j; |
212 |
PhotonIdx pIdx; |
213 |
Photon photon; |
214 |
RAY ray; |
215 |
PhotonMap nuPmap; |
216 |
|
217 |
repComplete = numPreComp = finalGather * pmap -> numPhotons; |
218 |
|
219 |
if (verbose) { |
220 |
sprintf(errmsg, |
221 |
"\nPrecomputing irradiance for %ld global photons\n", |
222 |
numPreComp); |
223 |
eputs(errmsg); |
224 |
#if NIX |
225 |
fflush(stderr); |
226 |
#endif |
227 |
} |
228 |
|
229 |
/* Copy photon map for precomputed photons */ |
230 |
memcpy(&nuPmap, pmap, sizeof(PhotonMap)); |
231 |
|
232 |
/* Zero counters, init new heap and extents */ |
233 |
nuPmap.numPhotons = 0; |
234 |
initPhotonHeap(&nuPmap); |
235 |
|
236 |
for (j = 0; j < 3; j++) { |
237 |
nuPmap.minPos [j] = FHUGE; |
238 |
nuPmap.maxPos [j] = -FHUGE; |
239 |
} |
240 |
|
241 |
/* Record start time, baby */ |
242 |
repStartTime = time(NULL); |
243 |
#ifdef SIGCONT |
244 |
signal(SIGCONT, pmapPreCompReport); |
245 |
#endif |
246 |
repProgress = 0; |
247 |
|
248 |
photonRay(NULL, &ray, PRIMARY, NULL); |
249 |
ray.ro = NULL; |
250 |
|
251 |
for (i = 0; i < numPreComp; i++) { |
252 |
/* Get random photon from stratified distribution in source heap to |
253 |
* avoid duplicates and clustering */ |
254 |
pIdx = firstPhoton(pmap) + |
255 |
(unsigned long)((i + pmapRandom(pmap -> randState)) / |
256 |
finalGather); |
257 |
getPhoton(pmap, pIdx, &photon); |
258 |
|
259 |
/* Init dummy photon ray with intersection at photon position */ |
260 |
VCOPY(ray.rop, photon.pos); |
261 |
for (j = 0; j < 3; j++) |
262 |
ray.ron [j] = photon.norm [j] / 127.0; |
263 |
|
264 |
/* Get density estimate at photon position */ |
265 |
photonDensity(pmap, &ray, ray.rcol); |
266 |
|
267 |
/* Append photon to new heap from ray */ |
268 |
newPhoton(&nuPmap, &ray); |
269 |
|
270 |
/* Update progress */ |
271 |
repProgress++; |
272 |
|
273 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
274 |
pmapPreCompReport(); |
275 |
#ifdef SIGCONT |
276 |
else signal(SIGCONT, pmapPreCompReport); |
277 |
#endif |
278 |
} |
279 |
|
280 |
/* Flush heap */ |
281 |
flushPhotonHeap(&nuPmap); |
282 |
|
283 |
#ifdef SIGCONT |
284 |
signal(SIGCONT, SIG_DFL); |
285 |
#endif |
286 |
|
287 |
/* Trash original pmap, replace with precomputed one */ |
288 |
deletePhotons(pmap); |
289 |
memcpy(pmap, &nuPmap, sizeof(PhotonMap)); |
290 |
|
291 |
if (verbose) { |
292 |
eputs("\nRebuilding precomputed photon map\n"); |
293 |
#if NIX |
294 |
fflush(stderr); |
295 |
#endif |
296 |
} |
297 |
|
298 |
/* Rebuild underlying data structure, destroying heap */ |
299 |
buildPhotonMap(pmap, NULL, NULL, 1); |
300 |
} |
301 |
|
302 |
|
303 |
|
304 |
typedef struct { |
305 |
unsigned long numPhotons [NUM_PMAP_TYPES], |
306 |
numEmitted, numComplete; |
307 |
} PhotonCnt; |
308 |
|
309 |
|
310 |
|
311 |
void distribPhotons (PhotonMap **pmaps, unsigned numProc) |
312 |
{ |
313 |
EmissionMap emap; |
314 |
char errmsg2 [128], shmFname [PMAP_TMPFNLEN]; |
315 |
unsigned t, srcIdx, proc; |
316 |
double totalFlux = 0; |
317 |
int shmFile, stat, pid; |
318 |
PhotonMap *pm; |
319 |
PhotonCnt *photonCnt; |
320 |
|
321 |
for (t = 0; t < NUM_PMAP_TYPES && !pmaps [t]; t++); |
322 |
|
323 |
if (t >= NUM_PMAP_TYPES) |
324 |
error(USER, "no photon maps defined in distribPhotons"); |
325 |
|
326 |
if (!nsources) |
327 |
error(USER, "no light sources in distribPhotons"); |
328 |
|
329 |
/* =================================================================== |
330 |
* INITIALISATION - Set up emission and scattering funcs |
331 |
* =================================================================== */ |
332 |
emap.samples = NULL; |
333 |
emap.maxPartitions = MAXSPART; |
334 |
emap.partitions = (unsigned char*)malloc(emap.maxPartitions >> 1); |
335 |
if (!emap.partitions) |
336 |
error(INTERNAL, "can't allocate source partitions in distribPhotons"); |
337 |
|
338 |
/* Initialise all defined photon maps */ |
339 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
340 |
if (pmaps [t]) { |
341 |
initPhotonMap(pmaps [t], t); |
342 |
/* Open photon heapfile */ |
343 |
initPhotonHeap(pmaps [t]); |
344 |
/* Per-subprocess target count */ |
345 |
pmaps [t] -> distribTarget /= numProc; |
346 |
|
347 |
if (!pmaps [t] -> distribTarget) |
348 |
error(INTERNAL, "no photons to distribute in distribPhotons"); |
349 |
} |
350 |
|
351 |
initPhotonEmissionFuncs(); |
352 |
initPhotonScatterFuncs(); |
353 |
|
354 |
/* Get photon ports from modifier list */ |
355 |
getPhotonPorts(photonPortList); |
356 |
|
357 |
/* Get photon sensor modifiers */ |
358 |
getPhotonSensors(photonSensorList); |
359 |
|
360 |
#if NIX |
361 |
/* Set up shared mem for photon counters (zeroed by ftruncate) */ |
362 |
strcpy(shmFname, PMAP_TMPFNAME); |
363 |
shmFile = mkstemp(shmFname); |
364 |
|
365 |
if (shmFile < 0 || ftruncate(shmFile, sizeof(*photonCnt)) < 0) |
366 |
error(SYSTEM, "failed shared mem init in distribPhotons"); |
367 |
|
368 |
photonCnt = mmap(NULL, sizeof(*photonCnt), PROT_READ | PROT_WRITE, |
369 |
MAP_SHARED, shmFile, 0); |
370 |
|
371 |
if (photonCnt == MAP_FAILED) |
372 |
error(SYSTEM, "failed mapping shared memory in distribPhotons"); |
373 |
#else |
374 |
/* Allocate photon counters statically on Windoze */ |
375 |
if (!(photonCnt = malloc(sizeof(PhotonCnt)))) |
376 |
error(SYSTEM, "failed trivial malloc in distribPhotons"); |
377 |
photonCnt -> numEmitted = photonCnt -> numComplete = 0; |
378 |
#endif /* NIX */ |
379 |
|
380 |
if (verbose) { |
381 |
sprintf(errmsg, "\nIntegrating flux from %d sources", nsources); |
382 |
|
383 |
if (photonPorts) { |
384 |
sprintf(errmsg2, " via %d ports", numPhotonPorts); |
385 |
strcat(errmsg, errmsg2); |
386 |
} |
387 |
|
388 |
strcat(errmsg, "\n"); |
389 |
eputs(errmsg); |
390 |
} |
391 |
|
392 |
/* =================================================================== |
393 |
* FLUX INTEGRATION - Get total photon flux from light sources |
394 |
* =================================================================== */ |
395 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
396 |
unsigned portCnt = 0; |
397 |
emap.src = source + srcIdx; |
398 |
|
399 |
do { /* Need at least one iteration if no ports! */ |
400 |
emap.port = emap.src -> sflags & SDISTANT ? photonPorts + portCnt |
401 |
: NULL; |
402 |
photonPartition [emap.src -> so -> otype] (&emap); |
403 |
|
404 |
if (verbose) { |
405 |
sprintf(errmsg, "\tIntegrating flux from source %s ", |
406 |
source [srcIdx].so -> oname); |
407 |
|
408 |
if (emap.port) { |
409 |
sprintf(errmsg2, "via port %s ", |
410 |
photonPorts [portCnt].so -> oname); |
411 |
strcat(errmsg, errmsg2); |
412 |
} |
413 |
|
414 |
sprintf(errmsg2, "(%lu partitions)\n", emap.numPartitions); |
415 |
strcat(errmsg, errmsg2); |
416 |
eputs(errmsg); |
417 |
#if NIX |
418 |
fflush(stderr); |
419 |
#endif |
420 |
} |
421 |
|
422 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
423 |
emap.partitionCnt++) { |
424 |
initPhotonEmission(&emap, pdfSamples); |
425 |
totalFlux += colorAvg(emap.partFlux); |
426 |
} |
427 |
|
428 |
portCnt++; |
429 |
} while (portCnt < numPhotonPorts); |
430 |
} |
431 |
|
432 |
if (totalFlux < FTINY) |
433 |
error(USER, "zero flux from light sources"); |
434 |
|
435 |
/* Record start time for progress reports */ |
436 |
repStartTime = time(NULL); |
437 |
|
438 |
if (verbose) { |
439 |
sprintf(errmsg, "\nPhoton distribution @ %d procs\n", numProc); |
440 |
eputs(errmsg); |
441 |
} |
442 |
|
443 |
/* MAIN LOOP */ |
444 |
for (proc = 0; proc < numProc; proc++) { |
445 |
#if NIX |
446 |
if (!(pid = fork())) { |
447 |
/* SUBPROCESS ENTERS HERE; open and mmapped files inherited */ |
448 |
#else |
449 |
if (1) { |
450 |
/* No subprocess under Windoze */ |
451 |
#endif |
452 |
/* Local photon counters for this subprocess */ |
453 |
unsigned passCnt = 0, prePassCnt = 0; |
454 |
unsigned long lastNumPhotons [NUM_PMAP_TYPES]; |
455 |
unsigned long localNumEmitted = 0; /* Num photons emitted by this |
456 |
subprocess alone */ |
457 |
|
458 |
/* Seed RNGs from PID for decorellated photon distribution */ |
459 |
pmapSeed(randSeed + proc, partState); |
460 |
pmapSeed(randSeed + (proc + 1) % numProc, emitState); |
461 |
pmapSeed(randSeed + (proc + 2) % numProc, cntState); |
462 |
pmapSeed(randSeed + (proc + 3) % numProc, mediumState); |
463 |
pmapSeed(randSeed + (proc + 4) % numProc, scatterState); |
464 |
pmapSeed(randSeed + (proc + 5) % numProc, rouletteState); |
465 |
|
466 |
#ifdef DEBUG_PMAP |
467 |
/* Output child process PID after random delay to prevent corrupted |
468 |
* console output due to race condition */ |
469 |
usleep(1e6 * pmapRandom(rouletteState)); |
470 |
fprintf(stderr, "Proc %d: PID = %d " |
471 |
"(waiting 10 sec to attach debugger...)\n", |
472 |
proc, getpid()); |
473 |
/* Allow time for debugger to attach to child process */ |
474 |
sleep(10); |
475 |
#endif |
476 |
|
477 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
478 |
lastNumPhotons [t] = 0; |
479 |
|
480 |
/* ============================================================= |
481 |
* 2-PASS PHOTON DISTRIBUTION |
482 |
* Pass 1 (pre): emit fraction of target photon count |
483 |
* Pass 2 (main): based on outcome of pass 1, estimate remaining |
484 |
* number of photons to emit to approximate target |
485 |
* count |
486 |
* ============================================================= */ |
487 |
do { |
488 |
double numEmit; |
489 |
|
490 |
if (!passCnt) { |
491 |
/* INIT PASS 1 */ |
492 |
/* Skip if no photons contributed after sufficient |
493 |
* iterations; make it clear to user which photon maps are |
494 |
* missing so (s)he can check geometry and materials */ |
495 |
if (++prePassCnt > maxPreDistrib) { |
496 |
sprintf(errmsg, "proc %d: too many prepasses", proc); |
497 |
|
498 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
499 |
if (pmaps [t] && !pmaps [t] -> numPhotons) { |
500 |
sprintf(errmsg2, ", no %s photons stored", |
501 |
pmapName [t]); |
502 |
strcat(errmsg, errmsg2); |
503 |
} |
504 |
|
505 |
error(USER, errmsg); |
506 |
break; |
507 |
} |
508 |
|
509 |
/* Num to emit is fraction of minimum target count */ |
510 |
numEmit = FHUGE; |
511 |
|
512 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
513 |
if (pmaps [t]) |
514 |
numEmit = min(pmaps [t] -> distribTarget, numEmit); |
515 |
|
516 |
numEmit *= preDistrib; |
517 |
} |
518 |
else { |
519 |
/* INIT PASS 2 */ |
520 |
/* Based on the outcome of the predistribution we can now |
521 |
* estimate how many more photons we have to emit for each |
522 |
* photon map to meet its respective target count. This |
523 |
* value is clamped to 0 in case the target has already been |
524 |
* exceeded in the pass 1. */ |
525 |
double maxDistribRatio = 0; |
526 |
|
527 |
/* Set the distribution ratio for each map; this indicates |
528 |
* how many photons of each respective type are stored per |
529 |
* emitted photon, and is used as probability for storing a |
530 |
* photon by newPhoton(). Since this biases the photon |
531 |
* density, newPhoton() promotes the flux of stored photons |
532 |
* to compensate. */ |
533 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
534 |
if ((pm = pmaps [t])) { |
535 |
pm -> distribRatio = (double)pm -> distribTarget / |
536 |
pm -> numPhotons - 1; |
537 |
|
538 |
/* Check if photon map "overflowed", i.e. exceeded its |
539 |
* target count in the prepass; correcting the photon |
540 |
* flux via the distribution ratio is no longer |
541 |
* possible, as no more photons of this type will be |
542 |
* stored, so notify the user rather than deliver |
543 |
* incorrect results. In future we should handle this |
544 |
* more intelligently by using the photonFlux in each |
545 |
* photon map to individually correct the flux after |
546 |
* distribution. */ |
547 |
if (pm -> distribRatio <= FTINY) { |
548 |
sprintf(errmsg, "%s photon map overflow in " |
549 |
"prepass, reduce -apD", pmapName [t]); |
550 |
error(INTERNAL, errmsg); |
551 |
} |
552 |
|
553 |
maxDistribRatio = max(pm -> distribRatio, |
554 |
maxDistribRatio); |
555 |
} |
556 |
|
557 |
/* Normalise distribution ratios and calculate number of |
558 |
* photons to emit in main pass */ |
559 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
560 |
if ((pm = pmaps [t])) |
561 |
pm -> distribRatio /= maxDistribRatio; |
562 |
|
563 |
if ((numEmit = localNumEmitted * maxDistribRatio) < FTINY) |
564 |
/* No photons left to distribute in main pass */ |
565 |
break; |
566 |
} |
567 |
|
568 |
/* Update shared completion counter for progreport by parent */ |
569 |
photonCnt -> numComplete += numEmit; |
570 |
|
571 |
/* PHOTON DISTRIBUTION LOOP */ |
572 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
573 |
unsigned portCnt = 0; |
574 |
emap.src = source + srcIdx; |
575 |
|
576 |
do { /* Need at least one iteration if no ports! */ |
577 |
emap.port = emap.src -> sflags & SDISTANT |
578 |
? photonPorts + portCnt : NULL; |
579 |
photonPartition [emap.src -> so -> otype] (&emap); |
580 |
|
581 |
if (verbose && !proc) { |
582 |
/* Output from subproc 0 only to avoid race condition |
583 |
* on console I/O */ |
584 |
if (!passCnt) |
585 |
sprintf(errmsg, "\tPREPASS %d on source %s ", |
586 |
prePassCnt, source [srcIdx].so -> oname); |
587 |
else |
588 |
sprintf(errmsg, "\tMAIN PASS on source %s ", |
589 |
source [srcIdx].so -> oname); |
590 |
|
591 |
if (emap.port) { |
592 |
sprintf(errmsg2, "via port %s ", |
593 |
photonPorts [portCnt].so -> oname); |
594 |
strcat(errmsg, errmsg2); |
595 |
} |
596 |
|
597 |
sprintf(errmsg2, "(%lu partitions)\n", |
598 |
emap.numPartitions); |
599 |
strcat(errmsg, errmsg2); |
600 |
eputs(errmsg); |
601 |
#if NIX |
602 |
fflush(stderr); |
603 |
#endif |
604 |
} |
605 |
|
606 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
607 |
emap.partitionCnt++) { |
608 |
double partNumEmit; |
609 |
unsigned long partEmitCnt; |
610 |
|
611 |
/* Get photon origin within current source partishunn |
612 |
* and build emission map */ |
613 |
photonOrigin [emap.src -> so -> otype] (&emap); |
614 |
initPhotonEmission(&emap, pdfSamples); |
615 |
|
616 |
/* Number of photons to emit from ziss partishunn -- |
617 |
* proportional to flux; photon ray weight and scalar |
618 |
* flux are uniform (latter only varying in RGB). */ |
619 |
partNumEmit = numEmit * colorAvg(emap.partFlux) / |
620 |
totalFlux; |
621 |
partEmitCnt = (unsigned long)partNumEmit; |
622 |
|
623 |
/* Probabilistically account for fractional photons */ |
624 |
if (pmapRandom(cntState) < partNumEmit - partEmitCnt) |
625 |
partEmitCnt++; |
626 |
|
627 |
/* Update local and shared (global) emission counter */ |
628 |
photonCnt -> numEmitted += partEmitCnt; |
629 |
localNumEmitted += partEmitCnt; |
630 |
|
631 |
/* Integer counter avoids FP rounding errors during |
632 |
* iteration */ |
633 |
while (partEmitCnt--) { |
634 |
RAY photonRay; |
635 |
|
636 |
/* Emit photon based on PDF and trace through scene |
637 |
* until absorbed/leaked */ |
638 |
emitPhoton(&emap, &photonRay); |
639 |
#if 1 |
640 |
if (emap.port) |
641 |
/* !!! PHOTON PORT REJECTION SAMPLING HACK: set |
642 |
* !!! photon port as fake hit object for |
643 |
* !!! primary ray to check for intersection in |
644 |
* !!! tracePhoton() */ |
645 |
photonRay.ro = emap.port -> so; |
646 |
#endif |
647 |
tracePhoton(&photonRay); |
648 |
} |
649 |
|
650 |
/* Update shared global photon count for each pmap */ |
651 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
652 |
if (pmaps [t]) { |
653 |
photonCnt -> numPhotons [t] += |
654 |
pmaps [t] -> numPhotons - lastNumPhotons [t]; |
655 |
lastNumPhotons [t] = pmaps [t] -> numPhotons; |
656 |
} |
657 |
#if !NIX |
658 |
/* Synchronous progress report on Windoze */ |
659 |
if (!proc && photonRepTime > 0 && |
660 |
time(NULL) >= repLastTime + photonRepTime) { |
661 |
repEmitted = repProgress = photonCnt -> numEmitted; |
662 |
repComplete = photonCnt -> numComplete; |
663 |
pmapDistribReport(); |
664 |
} |
665 |
#endif |
666 |
} |
667 |
|
668 |
portCnt++; |
669 |
} while (portCnt < numPhotonPorts); |
670 |
} |
671 |
|
672 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
673 |
if (pmaps [t] && !pmaps [t] -> numPhotons) { |
674 |
/* Double preDistrib in case a photon map is empty and |
675 |
* redo pass 1 --> possibility of infinite loop for |
676 |
* pathological scenes (e.g. absorbing materials) */ |
677 |
preDistrib *= 2; |
678 |
break; |
679 |
} |
680 |
|
681 |
if (t >= NUM_PMAP_TYPES) |
682 |
/* No empty photon maps found; now do pass 2 */ |
683 |
passCnt++; |
684 |
} while (passCnt < 2); |
685 |
|
686 |
/* Flush heap buffa for every pmap one final time; |
687 |
* avoids potential data corruption! */ |
688 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
689 |
if (pmaps [t]) { |
690 |
flushPhotonHeap(pmaps [t]); |
691 |
/* Heap file closed automatically on exit |
692 |
fclose(pmaps [t] -> heap); */ |
693 |
#ifdef DEBUG_PMAP |
694 |
sprintf(errmsg, "Proc %d: total %ld photons\n", proc, |
695 |
pmaps [t] -> numPhotons); |
696 |
eputs(errmsg); |
697 |
#endif |
698 |
} |
699 |
#if NIX |
700 |
/* Terminate subprocess */ |
701 |
exit(0); |
702 |
#endif |
703 |
} |
704 |
else if (pid < 0) |
705 |
error(SYSTEM, "failed to fork subprocess in distribPhotons"); |
706 |
} |
707 |
|
708 |
#if NIX |
709 |
/* PARENT PROCESS CONTINUES HERE */ |
710 |
#ifdef SIGCONT |
711 |
/* Enable progress report signal handler */ |
712 |
signal(SIGCONT, pmapDistribReport); |
713 |
#endif |
714 |
/* Wait for subprocesses complete while reporting progress */ |
715 |
proc = numProc; |
716 |
while (proc) { |
717 |
while (waitpid(-1, &stat, WNOHANG) > 0) { |
718 |
/* Subprocess exited; check status */ |
719 |
if (!WIFEXITED(stat) || WEXITSTATUS(stat)) |
720 |
error(USER, "failed photon distribution"); |
721 |
|
722 |
--proc; |
723 |
} |
724 |
|
725 |
/* Nod off for a bit and update progress */ |
726 |
sleep(1); |
727 |
|
728 |
/* Asynchronous progress report from shared subprocess counters */ |
729 |
repEmitted = repProgress = photonCnt -> numEmitted; |
730 |
repComplete = photonCnt -> numComplete; |
731 |
|
732 |
repProgress = repComplete = 0; |
733 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
734 |
if ((pm = pmaps [t])) { |
735 |
/* Get global photon count from shmem updated by subprocs */ |
736 |
repProgress += pm -> numPhotons = photonCnt -> numPhotons [t]; |
737 |
repComplete += pm -> distribTarget; |
738 |
} |
739 |
repComplete *= numProc; |
740 |
|
741 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
742 |
pmapDistribReport(); |
743 |
#ifdef SIGCONT |
744 |
else signal(SIGCONT, pmapDistribReport); |
745 |
#endif |
746 |
} |
747 |
#endif /* NIX */ |
748 |
|
749 |
/* =================================================================== |
750 |
* POST-DISTRIBUTION - Set photon flux and build data struct for photon |
751 |
* storage, etc. |
752 |
* =================================================================== */ |
753 |
#ifdef SIGCONT |
754 |
/* Reset signal handler */ |
755 |
signal(SIGCONT, SIG_DFL); |
756 |
#endif |
757 |
free(emap.samples); |
758 |
|
759 |
/* Set photon flux */ |
760 |
totalFlux /= photonCnt -> numEmitted; |
761 |
#if NIX |
762 |
/* Photon counters no longer needed, unmap shared memory */ |
763 |
munmap(photonCnt, sizeof(*photonCnt)); |
764 |
close(shmFile); |
765 |
unlink(shmFname); |
766 |
#else |
767 |
free(photonCnt); |
768 |
#endif |
769 |
if (verbose) |
770 |
eputs("\n"); |
771 |
|
772 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
773 |
if (pmaps [t]) { |
774 |
if (verbose) { |
775 |
sprintf(errmsg, "Building %s photon map\n", pmapName [t]); |
776 |
eputs(errmsg); |
777 |
#if NIX |
778 |
fflush(stderr); |
779 |
#endif |
780 |
} |
781 |
|
782 |
/* Build underlying data structure; heap is destroyed */ |
783 |
buildPhotonMap(pmaps [t], &totalFlux, NULL, numProc); |
784 |
} |
785 |
|
786 |
/* Precompute photon irradiance if necessary */ |
787 |
if (preCompPmap) { |
788 |
if (verbose) |
789 |
eputs("\n"); |
790 |
preComputeGlobal(preCompPmap); |
791 |
} |
792 |
|
793 |
if (verbose) |
794 |
eputs("\n"); |
795 |
} |