| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: pmap.c,v 2.11 2016/05/17 17:39:47 rschregle Exp $"; |
| 3 |
#endif |
| 4 |
|
| 5 |
/* |
| 6 |
====================================================================== |
| 7 |
Photon map main module |
| 8 |
|
| 9 |
Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) |
| 10 |
(c) Fraunhofer Institute for Solar Energy Systems, |
| 11 |
(c) Lucerne University of Applied Sciences and Arts, |
| 12 |
supported by the Swiss National Science Foundation (SNSF, #147053) |
| 13 |
====================================================================== |
| 14 |
|
| 15 |
$Id: pmap.c,v 2.11 2016/05/17 17:39:47 rschregle Exp $ |
| 16 |
*/ |
| 17 |
|
| 18 |
|
| 19 |
|
| 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 |
#include <sys/stat.h> |
| 30 |
#include <sys/mman.h> |
| 31 |
#include <sys/wait.h> |
| 32 |
|
| 33 |
|
| 34 |
|
| 35 |
void savePmaps (const PhotonMap **pmaps, int argc, char **argv) |
| 36 |
{ |
| 37 |
unsigned t; |
| 38 |
|
| 39 |
for (t = 0; t < NUM_PMAP_TYPES; t++) { |
| 40 |
if (pmaps [t]) |
| 41 |
savePhotonMap(pmaps [t], pmaps [t] -> fileName, argc, argv); |
| 42 |
} |
| 43 |
} |
| 44 |
|
| 45 |
|
| 46 |
|
| 47 |
static int photonParticipate (RAY *ray) |
| 48 |
/* Trace photon through participating medium. Returns 1 if passed through, |
| 49 |
or 0 if absorbed and $*%&ed. Analogon to rayparticipate(). */ |
| 50 |
{ |
| 51 |
int i; |
| 52 |
RREAL cosTheta, cosPhi, du, dv; |
| 53 |
const float cext = colorAvg(ray -> cext), |
| 54 |
albedo = colorAvg(ray -> albedo); |
| 55 |
FVECT u, v; |
| 56 |
COLOR cvext; |
| 57 |
|
| 58 |
/* Mean free distance until interaction with medium */ |
| 59 |
ray -> rmax = -log(pmapRandom(mediumState)) / cext; |
| 60 |
|
| 61 |
while (!localhit(ray, &thescene)) { |
| 62 |
setcolor(cvext, exp(-ray -> rmax * ray -> cext [0]), |
| 63 |
exp(-ray -> rmax * ray -> cext [1]), |
| 64 |
exp(-ray -> rmax * ray -> cext [2])); |
| 65 |
|
| 66 |
/* Modify ray color and normalise */ |
| 67 |
multcolor(ray -> rcol, cvext); |
| 68 |
colorNorm(ray -> rcol); |
| 69 |
VCOPY(ray -> rorg, ray -> rop); |
| 70 |
|
| 71 |
if (albedo > FTINY && ray -> rlvl > 0) |
| 72 |
/* Add to volume photon map */ |
| 73 |
newPhoton(volumePmap, ray); |
| 74 |
|
| 75 |
/* Absorbed? */ |
| 76 |
if (pmapRandom(rouletteState) > albedo) |
| 77 |
return 0; |
| 78 |
|
| 79 |
/* Colour bleeding without attenuation (?) */ |
| 80 |
multcolor(ray -> rcol, ray -> albedo); |
| 81 |
scalecolor(ray -> rcol, 1 / albedo); |
| 82 |
|
| 83 |
/* Scatter photon */ |
| 84 |
cosTheta = ray -> gecc <= FTINY ? 2 * pmapRandom(scatterState) - 1 |
| 85 |
: 1 / (2 * ray -> gecc) * |
| 86 |
(1 + ray -> gecc * ray -> gecc - |
| 87 |
(1 - ray -> gecc * ray -> gecc) / |
| 88 |
(1 - ray -> gecc + 2 * ray -> gecc * |
| 89 |
pmapRandom(scatterState))); |
| 90 |
|
| 91 |
cosPhi = cos(2 * PI * pmapRandom(scatterState)); |
| 92 |
du = dv = sqrt(1 - cosTheta * cosTheta); /* sin(theta) */ |
| 93 |
du *= cosPhi; |
| 94 |
dv *= sqrt(1 - cosPhi * cosPhi); /* sin(phi) */ |
| 95 |
|
| 96 |
/* Get axes u & v perpendicular to photon direction */ |
| 97 |
i = 0; |
| 98 |
do { |
| 99 |
v [0] = v [1] = v [2] = 0; |
| 100 |
v [i++] = 1; |
| 101 |
fcross(u, v, ray -> rdir); |
| 102 |
} while (normalize(u) < FTINY); |
| 103 |
fcross(v, ray -> rdir, u); |
| 104 |
|
| 105 |
for (i = 0; i < 3; i++) |
| 106 |
ray -> rdir [i] = du * u [i] + dv * v [i] + |
| 107 |
cosTheta * ray -> rdir [i]; |
| 108 |
ray -> rlvl++; |
| 109 |
ray -> rmax = -log(pmapRandom(mediumState)) / cext; |
| 110 |
} |
| 111 |
|
| 112 |
setcolor(cvext, exp(-ray -> rot * ray -> cext [0]), |
| 113 |
exp(-ray -> rot * ray -> cext [1]), |
| 114 |
exp(-ray -> rot * ray -> cext [2])); |
| 115 |
|
| 116 |
/* Modify ray color and normalise */ |
| 117 |
multcolor(ray -> rcol, cvext); |
| 118 |
colorNorm(ray -> rcol); |
| 119 |
|
| 120 |
/* Passed through medium */ |
| 121 |
return 1; |
| 122 |
} |
| 123 |
|
| 124 |
|
| 125 |
|
| 126 |
void tracePhoton (RAY *ray) |
| 127 |
/* Follow photon as it bounces around... */ |
| 128 |
{ |
| 129 |
long mod; |
| 130 |
OBJREC* mat; |
| 131 |
|
| 132 |
if (ray -> rlvl > photonMaxBounce) { |
| 133 |
#ifdef PMAP_RUNAWAY_WARN |
| 134 |
error(WARNING, "runaway photon!"); |
| 135 |
#endif |
| 136 |
return; |
| 137 |
} |
| 138 |
|
| 139 |
if (colorAvg(ray -> cext) > FTINY && !photonParticipate(ray)) |
| 140 |
return; |
| 141 |
|
| 142 |
if (localhit(ray, &thescene)) { |
| 143 |
mod = ray -> ro -> omod; |
| 144 |
|
| 145 |
if ((ray -> clipset && inset(ray -> clipset, mod)) || mod == OVOID) { |
| 146 |
/* Transfer ray if modifier is VOID or clipped within antimatta */ |
| 147 |
RAY tray; |
| 148 |
photonRay(ray, &tray, PMAP_XFER, NULL); |
| 149 |
tracePhoton(&tray); |
| 150 |
} |
| 151 |
else { |
| 152 |
/* Scatter for modifier material */ |
| 153 |
mat = objptr(mod); |
| 154 |
photonScatter [mat -> otype] (mat, ray); |
| 155 |
} |
| 156 |
} |
| 157 |
} |
| 158 |
|
| 159 |
|
| 160 |
|
| 161 |
static void preComputeGlobal (PhotonMap *pmap) |
| 162 |
/* Precompute irradiance from global photons for final gathering for |
| 163 |
a random subset of finalGather * pmap -> numPhotons photons, and builds |
| 164 |
the photon map, discarding the original photons. */ |
| 165 |
/* !!! NOTE: PRECOMPUTATION WITH OOC CURRENTLY WITHOUT CACHE !!! */ |
| 166 |
{ |
| 167 |
unsigned long i, numPreComp; |
| 168 |
unsigned j; |
| 169 |
PhotonIdx pIdx; |
| 170 |
Photon photon; |
| 171 |
RAY ray; |
| 172 |
PhotonMap nuPmap; |
| 173 |
|
| 174 |
repComplete = numPreComp = finalGather * pmap -> numPhotons; |
| 175 |
|
| 176 |
if (photonRepTime) { |
| 177 |
sprintf(errmsg, "Precomputing irradiance for %ld global photons...\n", |
| 178 |
numPreComp); |
| 179 |
eputs(errmsg); |
| 180 |
fflush(stderr); |
| 181 |
} |
| 182 |
|
| 183 |
/* Copy photon map for precomputed photons */ |
| 184 |
memcpy(&nuPmap, pmap, sizeof(PhotonMap)); |
| 185 |
|
| 186 |
/* Zero counters, init new heap and extents */ |
| 187 |
nuPmap.numPhotons = 0; |
| 188 |
initPhotonHeap(&nuPmap); |
| 189 |
|
| 190 |
for (j = 0; j < 3; j++) { |
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nuPmap.minPos [j] = FHUGE; |
| 192 |
nuPmap.maxPos [j] = -FHUGE; |
| 193 |
} |
| 194 |
|
| 195 |
/* Record start time, baby */ |
| 196 |
repStartTime = time(NULL); |
| 197 |
#ifdef SIGCONT |
| 198 |
signal(SIGCONT, pmapPreCompReport); |
| 199 |
#endif |
| 200 |
repProgress = 0; |
| 201 |
|
| 202 |
photonRay(NULL, &ray, PRIMARY, NULL); |
| 203 |
ray.ro = NULL; |
| 204 |
|
| 205 |
for (i = 0; i < numPreComp; i++) { |
| 206 |
/* Get random photon from stratified distribution in source heap to |
| 207 |
* avoid duplicates and clutering */ |
| 208 |
pIdx = firstPhoton(pmap) + |
| 209 |
(unsigned long)((i + pmapRandom(pmap -> randState)) / |
| 210 |
finalGather); |
| 211 |
getPhoton(pmap, pIdx, &photon); |
| 212 |
|
| 213 |
/* Init dummy photon ray with intersection at photon position */ |
| 214 |
VCOPY(ray.rop, photon.pos); |
| 215 |
for (j = 0; j < 3; j++) |
| 216 |
ray.ron [j] = photon.norm [j] / 127.0; |
| 217 |
|
| 218 |
/* Get density estimate at photon position */ |
| 219 |
photonDensity(pmap, &ray, ray.rcol); |
| 220 |
|
| 221 |
/* Append photon to new heap from ray */ |
| 222 |
newPhoton(&nuPmap, &ray); |
| 223 |
|
| 224 |
/* Update progress */ |
| 225 |
repProgress++; |
| 226 |
|
| 227 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
| 228 |
pmapPreCompReport(); |
| 229 |
#ifdef SIGCONT |
| 230 |
else signal(SIGCONT, pmapPreCompReport); |
| 231 |
#endif |
| 232 |
} |
| 233 |
|
| 234 |
/* Flush heap */ |
| 235 |
flushPhotonHeap(&nuPmap); |
| 236 |
|
| 237 |
#ifdef SIGCONT |
| 238 |
signal(SIGCONT, SIG_DFL); |
| 239 |
#endif |
| 240 |
|
| 241 |
/* Trash original pmap, replace with precomputed one */ |
| 242 |
deletePhotons(pmap); |
| 243 |
memcpy(pmap, &nuPmap, sizeof(PhotonMap)); |
| 244 |
|
| 245 |
if (photonRepTime) { |
| 246 |
eputs("Rebuilding precomputed photon map...\n"); |
| 247 |
fflush(stderr); |
| 248 |
} |
| 249 |
|
| 250 |
/* Rebuild underlying data structure, destroying heap */ |
| 251 |
buildPhotonMap(pmap, NULL, NULL, 1); |
| 252 |
} |
| 253 |
|
| 254 |
|
| 255 |
|
| 256 |
typedef struct { |
| 257 |
unsigned long numPhotons [NUM_PMAP_TYPES], |
| 258 |
numEmitted, numComplete; |
| 259 |
} PhotonCnt; |
| 260 |
|
| 261 |
|
| 262 |
|
| 263 |
void distribPhotons (PhotonMap **pmaps, unsigned numProc) |
| 264 |
{ |
| 265 |
EmissionMap emap; |
| 266 |
char errmsg2 [128], shmFname [255]; |
| 267 |
unsigned t, srcIdx, proc; |
| 268 |
double totalFlux = 0; |
| 269 |
int shmFile, stat, pid; |
| 270 |
PhotonMap *pm; |
| 271 |
PhotonCnt *photonCnt; |
| 272 |
|
| 273 |
for (t = 0; t < NUM_PMAP_TYPES && !pmaps [t]; t++); |
| 274 |
|
| 275 |
if (t >= NUM_PMAP_TYPES) |
| 276 |
error(USER, "no photon maps defined in distribPhotons"); |
| 277 |
|
| 278 |
if (!nsources) |
| 279 |
error(USER, "no light sources in distribPhotons"); |
| 280 |
|
| 281 |
/* =================================================================== |
| 282 |
* INITIALISATION - Set up emission and scattering funcs |
| 283 |
* =================================================================== */ |
| 284 |
emap.samples = NULL; |
| 285 |
emap.maxPartitions = MAXSPART; |
| 286 |
emap.partitions = (unsigned char*)malloc(emap.maxPartitions >> 1); |
| 287 |
if (!emap.partitions) |
| 288 |
error(INTERNAL, "can't allocate source partitions in distribPhotons"); |
| 289 |
|
| 290 |
/* Initialise all defined photon maps */ |
| 291 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 292 |
if (pmaps [t]) { |
| 293 |
initPhotonMap(pmaps [t], t); |
| 294 |
/* Open photon heapfile */ |
| 295 |
initPhotonHeap(pmaps [t]); |
| 296 |
/* Per-subprocess target count */ |
| 297 |
pmaps [t] -> distribTarget /= numProc; |
| 298 |
} |
| 299 |
|
| 300 |
initPhotonEmissionFuncs(); |
| 301 |
initPhotonScatterFuncs(); |
| 302 |
|
| 303 |
/* Get photon ports if specified */ |
| 304 |
if (ambincl == 1) |
| 305 |
getPhotonPorts(); |
| 306 |
|
| 307 |
/* Get photon sensor modifiers */ |
| 308 |
getPhotonSensors(photonSensorList); |
| 309 |
|
| 310 |
/* Set up shared mem for photon counters (zeroed by ftruncate) */ |
| 311 |
#if 0 |
| 312 |
snprintf(shmFname, 255, PMAP_SHMFNAME, getpid()); |
| 313 |
shmFile = shm_open(shmFname, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR); |
| 314 |
#else |
| 315 |
strcpy(shmFname, PMAP_SHMFNAME); |
| 316 |
shmFile = mkstemp(shmFname); |
| 317 |
#endif |
| 318 |
|
| 319 |
if (shmFile < 0) |
| 320 |
error(SYSTEM, "failed opening shared memory file in distribPhotons"); |
| 321 |
|
| 322 |
if (ftruncate(shmFile, sizeof(*photonCnt)) < 0) |
| 323 |
error(SYSTEM, "failed setting shared memory size in distribPhotons"); |
| 324 |
|
| 325 |
photonCnt = mmap(NULL, sizeof(*photonCnt), PROT_READ | PROT_WRITE, |
| 326 |
MAP_SHARED, shmFile, 0); |
| 327 |
|
| 328 |
if (photonCnt == MAP_FAILED) |
| 329 |
error(SYSTEM, "failed mapping shared memory in distribPhotons"); |
| 330 |
|
| 331 |
if (photonRepTime) |
| 332 |
eputs("\n"); |
| 333 |
|
| 334 |
/* =================================================================== |
| 335 |
* FLUX INTEGRATION - Get total photon flux from light sources |
| 336 |
* =================================================================== */ |
| 337 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
| 338 |
unsigned portCnt = 0; |
| 339 |
emap.src = source + srcIdx; |
| 340 |
|
| 341 |
do { /* Need at least one iteration if no ports! */ |
| 342 |
emap.port = emap.src -> sflags & SDISTANT ? photonPorts + portCnt |
| 343 |
: NULL; |
| 344 |
photonPartition [emap.src -> so -> otype] (&emap); |
| 345 |
|
| 346 |
if (photonRepTime) { |
| 347 |
sprintf(errmsg, "Integrating flux from source %s ", |
| 348 |
source [srcIdx].so -> oname); |
| 349 |
|
| 350 |
if (emap.port) { |
| 351 |
sprintf(errmsg2, "via port %s ", |
| 352 |
photonPorts [portCnt].so -> oname); |
| 353 |
strcat(errmsg, errmsg2); |
| 354 |
} |
| 355 |
|
| 356 |
sprintf(errmsg2, "(%lu partitions)...\n", emap.numPartitions); |
| 357 |
strcat(errmsg, errmsg2); |
| 358 |
eputs(errmsg); |
| 359 |
fflush(stderr); |
| 360 |
} |
| 361 |
|
| 362 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
| 363 |
emap.partitionCnt++) { |
| 364 |
initPhotonEmission(&emap, pdfSamples); |
| 365 |
totalFlux += colorAvg(emap.partFlux); |
| 366 |
} |
| 367 |
|
| 368 |
portCnt++; |
| 369 |
} while (portCnt < numPhotonPorts); |
| 370 |
} |
| 371 |
|
| 372 |
if (totalFlux < FTINY) |
| 373 |
error(USER, "zero flux from light sources"); |
| 374 |
|
| 375 |
/* MAIN LOOP */ |
| 376 |
for (proc = 0; proc < numProc; proc++) { |
| 377 |
if (!(pid = fork())) { |
| 378 |
/* SUBPROCESS ENTERS HERE. |
| 379 |
All opened and memory mapped files are inherited */ |
| 380 |
unsigned passCnt = 0, prePassCnt = 0; |
| 381 |
unsigned long lastNumPhotons [NUM_PMAP_TYPES]; |
| 382 |
unsigned long localNumEmitted = 0; /* Num photons emitted by this |
| 383 |
subprocess alone */ |
| 384 |
|
| 385 |
/* Seed RNGs from PID for decorellated photon distribution */ |
| 386 |
pmapSeed(randSeed + proc, partState); |
| 387 |
pmapSeed(randSeed + proc, emitState); |
| 388 |
pmapSeed(randSeed + proc, cntState); |
| 389 |
pmapSeed(randSeed + proc, mediumState); |
| 390 |
pmapSeed(randSeed + proc, scatterState); |
| 391 |
pmapSeed(randSeed + proc, rouletteState); |
| 392 |
|
| 393 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 394 |
lastNumPhotons [t] = 0; |
| 395 |
|
| 396 |
/* ============================================================= |
| 397 |
* 2-PASS PHOTON DISTRIBUTION |
| 398 |
* Pass 1 (pre): emit fraction of target photon count |
| 399 |
* Pass 2 (main): based on outcome of pass 1, estimate remaining |
| 400 |
* number of photons to emit to approximate target |
| 401 |
* count |
| 402 |
* ============================================================= */ |
| 403 |
do { |
| 404 |
double numEmit; |
| 405 |
|
| 406 |
if (!passCnt) { |
| 407 |
/* INIT PASS 1 */ |
| 408 |
/* Skip if no photons contributed after sufficient |
| 409 |
* iterations; make it clear to user which photon maps are |
| 410 |
* missing so (s)he can check geometry and materials */ |
| 411 |
if (++prePassCnt > maxPreDistrib) { |
| 412 |
sprintf(errmsg, |
| 413 |
"proc %d, source %s: too many prepasses", |
| 414 |
proc, source [srcIdx].so -> oname); |
| 415 |
|
| 416 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 417 |
if (pmaps [t] && !pmaps [t] -> numPhotons) { |
| 418 |
sprintf(errmsg2, ", no %s photons stored", |
| 419 |
pmapName [t]); |
| 420 |
strcat(errmsg, errmsg2); |
| 421 |
} |
| 422 |
|
| 423 |
error(USER, errmsg); |
| 424 |
break; |
| 425 |
} |
| 426 |
|
| 427 |
/* Num to emit is fraction of minimum target count */ |
| 428 |
numEmit = FHUGE; |
| 429 |
|
| 430 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 431 |
if (pmaps [t]) |
| 432 |
numEmit = min(pmaps [t] -> distribTarget, numEmit); |
| 433 |
|
| 434 |
numEmit *= preDistrib; |
| 435 |
} |
| 436 |
else { |
| 437 |
/* INIT PASS 2 */ |
| 438 |
/* Based on the outcome of the predistribution we can now |
| 439 |
* estimate how many more photons we have to emit for each |
| 440 |
* photon map to meet its respective target count. This |
| 441 |
* value is clamped to 0 in case the target has already been |
| 442 |
* exceeded in the pass 1. */ |
| 443 |
double maxDistribRatio = 0; |
| 444 |
|
| 445 |
/* Set the distribution ratio for each map; this indicates |
| 446 |
* how many photons of each respective type are stored per |
| 447 |
* emitted photon, and is used as probability for storing a |
| 448 |
* photon by newPhoton(). Since this biases the photon |
| 449 |
* density, newPhoton() promotes the flux of stored photons |
| 450 |
* to compensate. */ |
| 451 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 452 |
if ((pm = pmaps [t])) { |
| 453 |
pm -> distribRatio = (double)pm -> distribTarget / |
| 454 |
pm -> numPhotons - 1; |
| 455 |
|
| 456 |
/* Check if photon map "overflowed", i.e. exceeded its |
| 457 |
* target count in the prepass; correcting the photon |
| 458 |
* flux via the distribution ratio is no longer |
| 459 |
* possible, as no more photons of this type will be |
| 460 |
* stored, so notify the user rather than deliver |
| 461 |
* incorrect results. In future we should handle this |
| 462 |
* more intelligently by using the photonFlux in each |
| 463 |
* photon map to individually correct the flux after |
| 464 |
* distribution. */ |
| 465 |
if (pm -> distribRatio <= FTINY) { |
| 466 |
sprintf(errmsg, "%s photon map overflow in " |
| 467 |
"prepass, reduce -apD", pmapName [t]); |
| 468 |
error(INTERNAL, errmsg); |
| 469 |
} |
| 470 |
|
| 471 |
maxDistribRatio = max(pm -> distribRatio, |
| 472 |
maxDistribRatio); |
| 473 |
} |
| 474 |
|
| 475 |
/* Normalise distribution ratios and calculate number of |
| 476 |
* photons to emit in main pass */ |
| 477 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 478 |
if ((pm = pmaps [t])) |
| 479 |
pm -> distribRatio /= maxDistribRatio; |
| 480 |
|
| 481 |
if ((numEmit = localNumEmitted * maxDistribRatio) < FTINY) |
| 482 |
/* No photons left to distribute in main pass */ |
| 483 |
break; |
| 484 |
} |
| 485 |
|
| 486 |
/* Update shared completion counter for prog.report by parent */ |
| 487 |
photonCnt -> numComplete += numEmit; |
| 488 |
|
| 489 |
/* PHOTON DISTRIBUTION LOOP */ |
| 490 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
| 491 |
unsigned portCnt = 0; |
| 492 |
emap.src = source + srcIdx; |
| 493 |
|
| 494 |
do { /* Need at least one iteration if no ports! */ |
| 495 |
emap.port = emap.src -> sflags & SDISTANT |
| 496 |
? photonPorts + portCnt : NULL; |
| 497 |
photonPartition [emap.src -> so -> otype] (&emap); |
| 498 |
|
| 499 |
if (photonRepTime && !proc) { |
| 500 |
if (!passCnt) |
| 501 |
sprintf(errmsg, "PREPASS %d on source %s ", |
| 502 |
prePassCnt, source [srcIdx].so -> oname); |
| 503 |
else |
| 504 |
sprintf(errmsg, "MAIN PASS on source %s ", |
| 505 |
source [srcIdx].so -> oname); |
| 506 |
|
| 507 |
if (emap.port) { |
| 508 |
sprintf(errmsg2, "via port %s ", |
| 509 |
photonPorts [portCnt].so -> oname); |
| 510 |
strcat(errmsg, errmsg2); |
| 511 |
} |
| 512 |
|
| 513 |
sprintf(errmsg2, "(%lu partitions)\n", |
| 514 |
emap.numPartitions); |
| 515 |
strcat(errmsg, errmsg2); |
| 516 |
eputs(errmsg); |
| 517 |
fflush(stderr); |
| 518 |
} |
| 519 |
|
| 520 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
| 521 |
emap.partitionCnt++) { |
| 522 |
double partNumEmit; |
| 523 |
unsigned long partEmitCnt; |
| 524 |
|
| 525 |
/* Get photon origin within current source partishunn |
| 526 |
* and build emission map */ |
| 527 |
photonOrigin [emap.src -> so -> otype] (&emap); |
| 528 |
initPhotonEmission(&emap, pdfSamples); |
| 529 |
|
| 530 |
/* Number of photons to emit from ziss partishunn -- |
| 531 |
* proportional to flux; photon ray weight and scalar |
| 532 |
* flux are uniform (the latter only varying in RGB). |
| 533 |
* */ |
| 534 |
partNumEmit = numEmit * colorAvg(emap.partFlux) / |
| 535 |
totalFlux; |
| 536 |
partEmitCnt = (unsigned long)partNumEmit; |
| 537 |
|
| 538 |
/* Probabilistically account for fractional photons */ |
| 539 |
if (pmapRandom(cntState) < partNumEmit - partEmitCnt) |
| 540 |
partEmitCnt++; |
| 541 |
|
| 542 |
/* Update local and shared (global) emission counter */ |
| 543 |
photonCnt -> numEmitted += partEmitCnt; |
| 544 |
localNumEmitted += partEmitCnt; |
| 545 |
|
| 546 |
/* Integer counter avoids FP rounding errors during |
| 547 |
* iteration */ |
| 548 |
while (partEmitCnt--) { |
| 549 |
RAY photonRay; |
| 550 |
|
| 551 |
/* Emit photon based on PDF and trace through scene |
| 552 |
* until absorbed/leaked */ |
| 553 |
emitPhoton(&emap, &photonRay); |
| 554 |
tracePhoton(&photonRay); |
| 555 |
} |
| 556 |
|
| 557 |
/* Update shared global photon count for each pmap */ |
| 558 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 559 |
if (pmaps [t]) { |
| 560 |
photonCnt -> numPhotons [t] += |
| 561 |
pmaps [t] -> numPhotons - lastNumPhotons [t]; |
| 562 |
lastNumPhotons [t] = pmaps [t] -> numPhotons; |
| 563 |
} |
| 564 |
} |
| 565 |
|
| 566 |
portCnt++; |
| 567 |
} while (portCnt < numPhotonPorts); |
| 568 |
} |
| 569 |
|
| 570 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 571 |
if (pmaps [t] && !pmaps [t] -> numPhotons) { |
| 572 |
/* Double preDistrib in case a photon map is empty and |
| 573 |
* redo pass 1 --> possibility of infinite loop for |
| 574 |
* pathological scenes (e.g. absorbing materials) */ |
| 575 |
preDistrib *= 2; |
| 576 |
break; |
| 577 |
} |
| 578 |
|
| 579 |
if (t >= NUM_PMAP_TYPES) { |
| 580 |
/* No empty photon maps found; now do pass 2 */ |
| 581 |
passCnt++; |
| 582 |
#if 0 |
| 583 |
if (photonRepTime) |
| 584 |
eputs("\n"); |
| 585 |
#endif |
| 586 |
} |
| 587 |
} while (passCnt < 2); |
| 588 |
|
| 589 |
/* Unmap shared photon counters */ |
| 590 |
#if 0 |
| 591 |
munmap(photonCnt, sizeof(*photonCnt)); |
| 592 |
close(shmFile); |
| 593 |
#endif |
| 594 |
|
| 595 |
/* Flush heap buffa for every pmap one final time; this is required |
| 596 |
* to prevent data corruption! */ |
| 597 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 598 |
if (pmaps [t]) { |
| 599 |
#if 0 |
| 600 |
eputs("Final flush\n"); |
| 601 |
#endif |
| 602 |
flushPhotonHeap(pmaps [t]); |
| 603 |
fclose(pmaps [t] -> heap); |
| 604 |
#ifdef DEBUG_PMAP |
| 605 |
sprintf(errmsg, "Proc %d: total %ld photons\n", getpid(), |
| 606 |
pmaps [t] -> numPhotons); |
| 607 |
eputs(errmsg); |
| 608 |
#endif |
| 609 |
} |
| 610 |
|
| 611 |
exit(0); |
| 612 |
} |
| 613 |
else if (pid < 0) |
| 614 |
error(SYSTEM, "failed to fork subprocess in distribPhotons"); |
| 615 |
} |
| 616 |
|
| 617 |
/* PARENT PROCESS CONTINUES HERE */ |
| 618 |
/* Record start time and enable progress report signal handler */ |
| 619 |
repStartTime = time(NULL); |
| 620 |
#ifdef SIGCONT |
| 621 |
signal(SIGCONT, pmapDistribReport); |
| 622 |
#endif |
| 623 |
|
| 624 |
if (photonRepTime) |
| 625 |
eputs("\n"); |
| 626 |
|
| 627 |
/* Wait for subprocesses to complete while reporting progress */ |
| 628 |
proc = numProc; |
| 629 |
while (proc) { |
| 630 |
while (waitpid(-1, &stat, WNOHANG) > 0) { |
| 631 |
/* Subprocess exited; check status */ |
| 632 |
if (!WIFEXITED(stat) || WEXITSTATUS(stat)) |
| 633 |
error(USER, "failed photon distribution"); |
| 634 |
|
| 635 |
--proc; |
| 636 |
} |
| 637 |
|
| 638 |
/* Nod off for a bit and update progress */ |
| 639 |
sleep(1); |
| 640 |
/* Update progress report from shared subprocess counters */ |
| 641 |
repEmitted = repProgress = photonCnt -> numEmitted; |
| 642 |
repComplete = photonCnt -> numComplete; |
| 643 |
|
| 644 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 645 |
if ((pm = pmaps [t])) { |
| 646 |
#if 0 |
| 647 |
/* Get photon count from heapfile size for progress update */ |
| 648 |
fseek(pm -> heap, 0, SEEK_END); |
| 649 |
pm -> numPhotons = ftell(pm -> heap) / sizeof(Photon); */ |
| 650 |
#else |
| 651 |
/* Get global photon count from shmem updated by subprocs */ |
| 652 |
pm -> numPhotons = photonCnt -> numPhotons [t]; |
| 653 |
#endif |
| 654 |
} |
| 655 |
|
| 656 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
| 657 |
pmapDistribReport(); |
| 658 |
#ifdef SIGCONT |
| 659 |
else signal(SIGCONT, pmapDistribReport); |
| 660 |
#endif |
| 661 |
} |
| 662 |
|
| 663 |
/* =================================================================== |
| 664 |
* POST-DISTRIBUTION - Set photon flux and build data struct for photon |
| 665 |
* storage, etc. |
| 666 |
* =================================================================== */ |
| 667 |
#ifdef SIGCONT |
| 668 |
signal(SIGCONT, SIG_DFL); |
| 669 |
#endif |
| 670 |
free(emap.samples); |
| 671 |
|
| 672 |
/* Set photon flux (repProgress is total num emitted) */ |
| 673 |
totalFlux /= photonCnt -> numEmitted; |
| 674 |
|
| 675 |
/* Photon counters no longer needed, unmap shared memory */ |
| 676 |
munmap(photonCnt, sizeof(*photonCnt)); |
| 677 |
close(shmFile); |
| 678 |
#if 0 |
| 679 |
shm_unlink(shmFname); |
| 680 |
#else |
| 681 |
unlink(shmFname); |
| 682 |
#endif |
| 683 |
|
| 684 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
| 685 |
if (pmaps [t]) { |
| 686 |
if (photonRepTime) { |
| 687 |
sprintf(errmsg, "\nBuilding %s photon map...\n", pmapName [t]); |
| 688 |
eputs(errmsg); |
| 689 |
fflush(stderr); |
| 690 |
} |
| 691 |
|
| 692 |
/* Build underlying data structure; heap is destroyed */ |
| 693 |
buildPhotonMap(pmaps [t], &totalFlux, NULL, numProc); |
| 694 |
} |
| 695 |
|
| 696 |
/* Precompute photon irradiance if necessary */ |
| 697 |
if (preCompPmap) |
| 698 |
preComputeGlobal(preCompPmap); |
| 699 |
} |
