| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: pmapcontrib.c,v 2.14 2017/08/14 21:12:10 rschregle Exp $"; |
| 3 |
#endif |
| 4 |
|
| 5 |
/* |
| 6 |
====================================================================== |
| 7 |
Photon map for light source contributions |
| 8 |
|
| 9 |
Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) |
| 10 |
(c) Lucerne University of Applied Sciences and Arts, |
| 11 |
supported by the Swiss National Science Foundation (SNSF, #147053) |
| 12 |
====================================================================== |
| 13 |
|
| 14 |
$Id: pmapcontrib.c,v 2.14 2017/08/14 21:12:10 rschregle Exp $ |
| 15 |
*/ |
| 16 |
|
| 17 |
|
| 18 |
#include "pmapcontrib.h" |
| 19 |
#include "pmapmat.h" |
| 20 |
#include "pmapsrc.h" |
| 21 |
#include "pmaprand.h" |
| 22 |
#include "pmapio.h" |
| 23 |
#include "pmapdiag.h" |
| 24 |
#include "rcontrib.h" |
| 25 |
#include "otypes.h" |
| 26 |
#if NIX |
| 27 |
#include <sys/mman.h> |
| 28 |
#include <sys/wait.h> |
| 29 |
#endif |
| 30 |
|
| 31 |
|
| 32 |
static PhotonPrimaryIdx newPhotonPrimary (PhotonMap *pmap, |
| 33 |
const RAY *primRay, |
| 34 |
FILE *primHeap) |
| 35 |
/* Add primary ray for emitted photon and save light source index, origin on |
| 36 |
* source, and emitted direction; used by contrib photons. The current |
| 37 |
* primary is stored in pmap -> lastPrimary. If the previous primary |
| 38 |
* contributed photons (has srcIdx >= 0), it's appended to primHeap. If |
| 39 |
* primRay == NULL, the current primary is still flushed, but no new primary |
| 40 |
* is set. Returns updated primary counter pmap -> numPrimary. */ |
| 41 |
{ |
| 42 |
if (!pmap || !primHeap) |
| 43 |
return 0; |
| 44 |
|
| 45 |
/* Check if last primary ray has spawned photons (srcIdx >= 0, see |
| 46 |
* newPhoton()), in which case we save it to the primary heap file |
| 47 |
* before clobbering it */ |
| 48 |
if (pmap -> lastPrimary.srcIdx >= 0) { |
| 49 |
if (!fwrite(&pmap -> lastPrimary, sizeof(PhotonPrimary), 1, primHeap)) |
| 50 |
error(SYSTEM, "failed writing photon primary in newPhotonPrimary"); |
| 51 |
|
| 52 |
pmap -> numPrimary++; |
| 53 |
if (pmap -> numPrimary > PMAP_MAXPRIMARY) |
| 54 |
error(INTERNAL, "photon primary overflow in newPhotonPrimary"); |
| 55 |
} |
| 56 |
|
| 57 |
/* Mark unused with negative source index until path spawns a photon (see |
| 58 |
* newPhoton()) */ |
| 59 |
pmap -> lastPrimary.srcIdx = -1; |
| 60 |
|
| 61 |
if (primRay) { |
| 62 |
FVECT dvec; |
| 63 |
|
| 64 |
#ifdef PMAP_PRIMARYDIR |
| 65 |
/* Reverse incident direction to point to light source */ |
| 66 |
dvec [0] = -primRay -> rdir [0]; |
| 67 |
dvec [1] = -primRay -> rdir [1]; |
| 68 |
dvec [2] = -primRay -> rdir [2]; |
| 69 |
pmap -> lastPrimary.dir = encodedir(dvec); |
| 70 |
#endif |
| 71 |
#ifdef PMAP_PRIMARYPOS |
| 72 |
VCOPY(pmap -> lastPrimary.pos, primRay -> rop); |
| 73 |
#endif |
| 74 |
} |
| 75 |
|
| 76 |
return pmap -> numPrimary; |
| 77 |
} |
| 78 |
|
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|
| 80 |
|
| 81 |
#ifdef DEBUG_PMAP |
| 82 |
static int checkPrimaryHeap (FILE *file) |
| 83 |
/* Check heap for ordered primaries */ |
| 84 |
{ |
| 85 |
Photon p, lastp; |
| 86 |
int i, dup; |
| 87 |
|
| 88 |
rewind(file); |
| 89 |
memset(&lastp, 0, sizeof(lastp)); |
| 90 |
|
| 91 |
while (fread(&p, sizeof(p), 1, file)) { |
| 92 |
dup = 1; |
| 93 |
|
| 94 |
for (i = 0; i <= 2; i++) { |
| 95 |
if (p.pos [i] < thescene.cuorg [i] || |
| 96 |
p.pos [i] > thescene.cuorg [i] + thescene.cusize) { |
| 97 |
|
| 98 |
sprintf(errmsg, "corrupt photon in heap at [%f, %f, %f]\n", |
| 99 |
p.pos [0], p.pos [1], p.pos [2]); |
| 100 |
error(WARNING, errmsg); |
| 101 |
} |
| 102 |
|
| 103 |
dup &= p.pos [i] == lastp.pos [i]; |
| 104 |
} |
| 105 |
|
| 106 |
if (dup) { |
| 107 |
sprintf(errmsg, |
| 108 |
"consecutive duplicate photon in heap at [%f, %f, %f]\n", |
| 109 |
p.pos [0], p.pos [1], p.pos [2]); |
| 110 |
error(WARNING, errmsg); |
| 111 |
} |
| 112 |
} |
| 113 |
|
| 114 |
return 0; |
| 115 |
} |
| 116 |
#endif |
| 117 |
|
| 118 |
|
| 119 |
|
| 120 |
static PhotonPrimaryIdx buildPrimaries (PhotonMap *pmap, FILE **primaryHeap, |
| 121 |
char **primaryHeapFname, |
| 122 |
PhotonPrimaryIdx *primaryOfs, |
| 123 |
unsigned numHeaps) |
| 124 |
/* Consolidate per-subprocess photon primary heaps into the primary array |
| 125 |
* pmap -> primaries. Returns offset for primary index linearisation in |
| 126 |
* numPrimary. The heap files in primaryHeap are closed on return. */ |
| 127 |
{ |
| 128 |
PhotonPrimaryIdx heapLen; |
| 129 |
unsigned heap; |
| 130 |
|
| 131 |
if (!pmap || !primaryHeap || !primaryOfs || !numHeaps) |
| 132 |
return 0; |
| 133 |
|
| 134 |
pmap -> numPrimary = 0; |
| 135 |
|
| 136 |
for (heap = 0; heap < numHeaps; heap++) { |
| 137 |
primaryOfs [heap] = pmap -> numPrimary; |
| 138 |
|
| 139 |
if (fseek(primaryHeap [heap], 0, SEEK_END) < 0) |
| 140 |
error(SYSTEM, "failed photon primary seek in buildPrimaries"); |
| 141 |
pmap -> numPrimary += heapLen = ftell(primaryHeap [heap]) / |
| 142 |
sizeof(PhotonPrimary); |
| 143 |
|
| 144 |
pmap -> primaries = realloc(pmap -> primaries, |
| 145 |
pmap -> numPrimary * |
| 146 |
sizeof(PhotonPrimary)); |
| 147 |
if (!pmap -> primaries) |
| 148 |
error(SYSTEM, "failed photon primary alloc in buildPrimaries"); |
| 149 |
|
| 150 |
rewind(primaryHeap [heap]); |
| 151 |
if (fread(pmap -> primaries + primaryOfs [heap], sizeof(PhotonPrimary), |
| 152 |
heapLen, primaryHeap [heap]) != heapLen) |
| 153 |
error(SYSTEM, "failed reading photon primaries in buildPrimaries"); |
| 154 |
|
| 155 |
fclose(primaryHeap [heap]); |
| 156 |
unlink(primaryHeapFname [heap]); |
| 157 |
} |
| 158 |
|
| 159 |
return pmap -> numPrimary; |
| 160 |
} |
| 161 |
|
| 162 |
|
| 163 |
|
| 164 |
/* Defs for photon emission counter array passed by sub-processes to parent |
| 165 |
* via shared memory */ |
| 166 |
typedef unsigned long PhotonContribCnt; |
| 167 |
|
| 168 |
/* Indices for photon emission counter array: num photons stored and num |
| 169 |
* emitted per source */ |
| 170 |
#define PHOTONCNT_NUMPHOT 0 |
| 171 |
#define PHOTONCNT_NUMEMIT(n) (1 + n) |
| 172 |
|
| 173 |
|
| 174 |
|
| 175 |
void distribPhotonContrib (PhotonMap* pm, unsigned numProc) |
| 176 |
{ |
| 177 |
EmissionMap emap; |
| 178 |
char errmsg2 [128], shmFname [PMAP_TMPFNLEN]; |
| 179 |
unsigned srcIdx, proc; |
| 180 |
int shmFile, stat, pid; |
| 181 |
double *srcFlux, /* Emitted flux per light source */ |
| 182 |
srcDistribTarget; /* Target photon count per source */ |
| 183 |
PhotonContribCnt *photonCnt; /* Photon emission counter array */ |
| 184 |
unsigned photonCntSize = sizeof(PhotonContribCnt) * |
| 185 |
PHOTONCNT_NUMEMIT(nsources); |
| 186 |
FILE **primaryHeap = NULL; |
| 187 |
char **primaryHeapFname = NULL; |
| 188 |
PhotonPrimaryIdx *primaryOfs = NULL; |
| 189 |
|
| 190 |
if (!pm) |
| 191 |
error(USER, "no photon map defined in distribPhotonContrib"); |
| 192 |
|
| 193 |
if (!nsources) |
| 194 |
error(USER, "no light sources in distribPhotonContrib"); |
| 195 |
|
| 196 |
if (nsources > MAXMODLIST) |
| 197 |
error(USER, "too many light sources in distribPhotonContrib"); |
| 198 |
|
| 199 |
/* Allocate photon flux per light source; this differs for every |
| 200 |
* source as all sources contribute the same number of distributed |
| 201 |
* photons (srcDistribTarget), hence the number of photons emitted per |
| 202 |
* source does not correlate with its emitted flux. The resulting flux |
| 203 |
* per photon is therefore adjusted individually for each source. */ |
| 204 |
if (!(srcFlux = calloc(nsources, sizeof(double)))) |
| 205 |
error(SYSTEM, "can't allocate source flux in distribPhotonContrib"); |
| 206 |
|
| 207 |
/* =================================================================== |
| 208 |
* INITIALISATION - Set up emission and scattering funcs |
| 209 |
* =================================================================== */ |
| 210 |
emap.samples = NULL; |
| 211 |
emap.src = NULL; |
| 212 |
emap.maxPartitions = MAXSPART; |
| 213 |
emap.partitions = (unsigned char*)malloc(emap.maxPartitions >> 1); |
| 214 |
if (!emap.partitions) |
| 215 |
error(USER, "can't allocate source partitions in distribPhotonContrib"); |
| 216 |
|
| 217 |
/* Initialise contrib photon map */ |
| 218 |
initPhotonMap(pm, PMAP_TYPE_CONTRIB); |
| 219 |
initPhotonHeap(pm); |
| 220 |
initPhotonEmissionFuncs(); |
| 221 |
initPhotonScatterFuncs(); |
| 222 |
|
| 223 |
/* Per-subprocess / per-source target counts */ |
| 224 |
pm -> distribTarget /= numProc; |
| 225 |
srcDistribTarget = nsources ? (double)pm -> distribTarget / nsources : 0; |
| 226 |
|
| 227 |
if (!pm -> distribTarget) |
| 228 |
error(INTERNAL, "no photons to distribute in distribPhotonContrib"); |
| 229 |
|
| 230 |
/* Get photon ports if specified */ |
| 231 |
if (ambincl == 1) |
| 232 |
getPhotonPorts(); |
| 233 |
|
| 234 |
/* Get photon sensor modifiers */ |
| 235 |
getPhotonSensors(photonSensorList); |
| 236 |
|
| 237 |
#if NIX |
| 238 |
/* Set up shared mem for photon counters (zeroed by ftruncate) */ |
| 239 |
strcpy(shmFname, PMAP_TMPFNAME); |
| 240 |
shmFile = mkstemp(shmFname); |
| 241 |
|
| 242 |
if (shmFile < 0 || ftruncate(shmFile, photonCntSize) < 0) |
| 243 |
error(SYSTEM, "failed shared mem init in distribPhotonContrib"); |
| 244 |
|
| 245 |
photonCnt = mmap(NULL, photonCntSize, PROT_READ | PROT_WRITE, |
| 246 |
MAP_SHARED, shmFile, 0); |
| 247 |
|
| 248 |
if (photonCnt == MAP_FAILED) |
| 249 |
error(SYSTEM, "failed shared mem mapping in distribPhotonContrib"); |
| 250 |
#else |
| 251 |
/* Allocate photon counters statically on Windoze */ |
| 252 |
if (!(photonCnt = malloc(photonCntSize))) |
| 253 |
error(SYSTEM, "failed trivial malloc in distribPhotonContrib"); |
| 254 |
|
| 255 |
for (srcIdx = 0; srcIdx < PHOTONCNT_NUMEMIT(nsources); srcIdx++) |
| 256 |
photonCnt [srcIdx] = 0; |
| 257 |
#endif /* NIX */ |
| 258 |
|
| 259 |
if (verbose) { |
| 260 |
sprintf(errmsg, "\nIntegrating flux from %d sources", nsources); |
| 261 |
|
| 262 |
if (photonPorts) { |
| 263 |
sprintf(errmsg2, " via %d ports", numPhotonPorts); |
| 264 |
strcat(errmsg, errmsg2); |
| 265 |
} |
| 266 |
|
| 267 |
strcat(errmsg, "\n"); |
| 268 |
eputs(errmsg); |
| 269 |
} |
| 270 |
|
| 271 |
/* ============================================================= |
| 272 |
* FLUX INTEGRATION - Get total flux emitted from sources/ports |
| 273 |
* ============================================================= */ |
| 274 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
| 275 |
unsigned portCnt = 0; |
| 276 |
srcFlux [srcIdx] = 0; |
| 277 |
emap.src = source + srcIdx; |
| 278 |
|
| 279 |
do { /* Need at least one iteration if no ports! */ |
| 280 |
emap.port = emap.src -> sflags & SDISTANT ? photonPorts + portCnt |
| 281 |
: NULL; |
| 282 |
photonPartition [emap.src -> so -> otype] (&emap); |
| 283 |
|
| 284 |
if (verbose) { |
| 285 |
sprintf(errmsg, "\tIntegrating flux from source %s ", |
| 286 |
source [srcIdx].so -> oname); |
| 287 |
|
| 288 |
if (emap.port) { |
| 289 |
sprintf(errmsg2, "via port %s ", |
| 290 |
photonPorts [portCnt].so -> oname); |
| 291 |
strcat(errmsg, errmsg2); |
| 292 |
} |
| 293 |
|
| 294 |
sprintf(errmsg2, "(%lu partitions)\n", emap.numPartitions); |
| 295 |
strcat(errmsg, errmsg2); |
| 296 |
eputs(errmsg); |
| 297 |
#if NIX |
| 298 |
fflush(stderr); |
| 299 |
#endif |
| 300 |
} |
| 301 |
|
| 302 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
| 303 |
emap.partitionCnt++) { |
| 304 |
initPhotonEmission(&emap, pdfSamples); |
| 305 |
srcFlux [srcIdx] += colorAvg(emap.partFlux); |
| 306 |
} |
| 307 |
|
| 308 |
portCnt++; |
| 309 |
} while (portCnt < numPhotonPorts); |
| 310 |
|
| 311 |
if (srcFlux [srcIdx] < FTINY) { |
| 312 |
sprintf(errmsg, "source %s has zero emission", |
| 313 |
source [srcIdx].so -> oname); |
| 314 |
error(WARNING, errmsg); |
| 315 |
} |
| 316 |
} |
| 317 |
|
| 318 |
/* Allocate & init per-subprocess primary heap files */ |
| 319 |
primaryHeap = calloc(numProc, sizeof(FILE*)); |
| 320 |
primaryHeapFname = calloc(numProc, sizeof(char*)); |
| 321 |
primaryOfs = calloc(numProc, sizeof(PhotonPrimaryIdx)); |
| 322 |
if (!primaryHeap || !primaryHeapFname || !primaryOfs) |
| 323 |
error(SYSTEM, "failed primary heap allocation in " |
| 324 |
"distribPhotonContrib"); |
| 325 |
|
| 326 |
for (proc = 0; proc < numProc; proc++) { |
| 327 |
primaryHeapFname [proc] = malloc(PMAP_TMPFNLEN); |
| 328 |
if (!primaryHeapFname [proc]) |
| 329 |
error(SYSTEM, "failed primary heap file allocation in " |
| 330 |
"distribPhotonContrib"); |
| 331 |
|
| 332 |
mktemp(strcpy(primaryHeapFname [proc], PMAP_TMPFNAME)); |
| 333 |
if (!(primaryHeap [proc] = fopen(primaryHeapFname [proc], "w+b"))) |
| 334 |
error(SYSTEM, "failed opening primary heap file in " |
| 335 |
"distribPhotonContrib"); |
| 336 |
} |
| 337 |
|
| 338 |
/* Record start time for progress reports */ |
| 339 |
repStartTime = time(NULL); |
| 340 |
|
| 341 |
if (verbose) { |
| 342 |
sprintf(errmsg, "\nPhoton distribution @ %d procs\n", numProc); |
| 343 |
eputs(errmsg); |
| 344 |
} |
| 345 |
|
| 346 |
/* MAIN LOOP */ |
| 347 |
for (proc = 0; proc < numProc; proc++) { |
| 348 |
#if NIX |
| 349 |
if (!(pid = fork())) { |
| 350 |
/* SUBPROCESS ENTERS HERE; opened and mmapped files inherited */ |
| 351 |
#else |
| 352 |
if (1) { |
| 353 |
/* No subprocess under Windoze */ |
| 354 |
#endif |
| 355 |
/* Local photon counters for this subprocess */ |
| 356 |
unsigned long lastNumPhotons = 0, localNumEmitted = 0; |
| 357 |
double photonFluxSum = 0; /* Accum. photon flux */ |
| 358 |
|
| 359 |
/* Seed RNGs from PID for decorellated photon distribution */ |
| 360 |
pmapSeed(randSeed + proc, partState); |
| 361 |
pmapSeed(randSeed + proc, emitState); |
| 362 |
pmapSeed(randSeed + proc, cntState); |
| 363 |
pmapSeed(randSeed + proc, mediumState); |
| 364 |
pmapSeed(randSeed + proc, scatterState); |
| 365 |
pmapSeed(randSeed + proc, rouletteState); |
| 366 |
|
| 367 |
/* ============================================================= |
| 368 |
* 2-PASS PHOTON DISTRIBUTION |
| 369 |
* Pass 1 (pre): emit fraction of target photon count |
| 370 |
* Pass 2 (main): based on outcome of pass 1, estimate remaining |
| 371 |
* number of photons to emit to approximate target |
| 372 |
* count |
| 373 |
* ============================================================= */ |
| 374 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
| 375 |
unsigned portCnt, passCnt = 0, prePassCnt = 0; |
| 376 |
float srcPreDistrib = preDistrib; |
| 377 |
double srcNumEmit = 0; /* # to emit from source */ |
| 378 |
unsigned long srcNumDistrib = pm -> numPhotons; /* # stored */ |
| 379 |
|
| 380 |
if (srcFlux [srcIdx] < FTINY) |
| 381 |
continue; |
| 382 |
|
| 383 |
while (passCnt < 2) { |
| 384 |
if (!passCnt) { |
| 385 |
/* INIT PASS 1 */ |
| 386 |
if (++prePassCnt > maxPreDistrib && !proc) { |
| 387 |
/* Warn if no photons contributed after sufficient |
| 388 |
* iterations; only output from subprocess 0 to reduce |
| 389 |
* console clutter */ |
| 390 |
sprintf(errmsg, |
| 391 |
"source %s: too many prepasses, skipped", |
| 392 |
source [srcIdx].so -> oname); |
| 393 |
error(WARNING, errmsg); |
| 394 |
break; |
| 395 |
} |
| 396 |
|
| 397 |
/* Num to emit is fraction of target count */ |
| 398 |
srcNumEmit = srcPreDistrib * srcDistribTarget; |
| 399 |
} |
| 400 |
else { |
| 401 |
/* INIT PASS 2 */ |
| 402 |
double srcPhotonFlux, avgPhotonFlux; |
| 403 |
|
| 404 |
/* Based on the outcome of the predistribution we can now |
| 405 |
* figure out how many more photons we have to emit from |
| 406 |
* the current source to meet the target count, |
| 407 |
* srcDistribTarget. This value is clamped to 0 in case |
| 408 |
* the target has already been exceeded in pass 1. |
| 409 |
* srcNumEmit and srcNumDistrib is the number of photons |
| 410 |
* emitted and distributed (stored) from the current |
| 411 |
* source in pass 1, respectively. */ |
| 412 |
srcNumDistrib = pm -> numPhotons - srcNumDistrib; |
| 413 |
srcNumEmit *= srcNumDistrib |
| 414 |
? max(srcDistribTarget/srcNumDistrib, 1) - 1 |
| 415 |
: 0; |
| 416 |
|
| 417 |
if (!srcNumEmit) |
| 418 |
/* No photons left to distribute in main pass */ |
| 419 |
break; |
| 420 |
|
| 421 |
srcPhotonFlux = srcFlux [srcIdx] / srcNumEmit; |
| 422 |
avgPhotonFlux = photonFluxSum / (srcIdx + 1); |
| 423 |
|
| 424 |
if (avgPhotonFlux > 0 && |
| 425 |
srcPhotonFlux / avgPhotonFlux < FTINY) { |
| 426 |
/* Skip source if its photon flux is grossly below the |
| 427 |
* running average, indicating negligible contributions |
| 428 |
* at the expense of excessive distribution time; only |
| 429 |
* output from subproc 0 to reduce console clutter */ |
| 430 |
sprintf(errmsg, |
| 431 |
"source %s: itsy bitsy photon flux, skipped", |
| 432 |
source [srcIdx].so -> oname); |
| 433 |
error(WARNING, errmsg); |
| 434 |
srcNumEmit = 0; |
| 435 |
} |
| 436 |
|
| 437 |
/* Update sum of photon flux per light source */ |
| 438 |
photonFluxSum += srcPhotonFlux; |
| 439 |
} |
| 440 |
|
| 441 |
portCnt = 0; |
| 442 |
do { /* Need at least one iteration if no ports! */ |
| 443 |
emap.src = source + srcIdx; |
| 444 |
emap.port = emap.src -> sflags & SDISTANT |
| 445 |
? photonPorts + portCnt : NULL; |
| 446 |
photonPartition [emap.src -> so -> otype] (&emap); |
| 447 |
|
| 448 |
if (verbose && !proc) { |
| 449 |
/* Output from subproc 0 only to avoid race condition |
| 450 |
* on console I/O */ |
| 451 |
if (!passCnt) |
| 452 |
sprintf(errmsg, "\tPREPASS %d on source %s ", |
| 453 |
prePassCnt, source [srcIdx].so -> oname); |
| 454 |
else |
| 455 |
sprintf(errmsg, "\tMAIN PASS on source %s ", |
| 456 |
source [srcIdx].so -> oname); |
| 457 |
|
| 458 |
if (emap.port) { |
| 459 |
sprintf(errmsg2, "via port %s ", |
| 460 |
photonPorts [portCnt].so -> oname); |
| 461 |
strcat(errmsg, errmsg2); |
| 462 |
} |
| 463 |
|
| 464 |
sprintf(errmsg2, "(%lu partitions)\n", |
| 465 |
emap.numPartitions); |
| 466 |
strcat(errmsg, errmsg2); |
| 467 |
eputs(errmsg); |
| 468 |
#if NIX |
| 469 |
fflush(stderr); |
| 470 |
#endif |
| 471 |
} |
| 472 |
|
| 473 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
| 474 |
emap.partitionCnt++) { |
| 475 |
double partNumEmit; |
| 476 |
unsigned long partEmitCnt; |
| 477 |
|
| 478 |
/* Get photon origin within current source partishunn |
| 479 |
* and build emission map */ |
| 480 |
photonOrigin [emap.src -> so -> otype] (&emap); |
| 481 |
initPhotonEmission(&emap, pdfSamples); |
| 482 |
|
| 483 |
/* Number of photons to emit from ziss partishunn; |
| 484 |
* scale according to its normalised contribushunn to |
| 485 |
* the emitted source flux */ |
| 486 |
partNumEmit = srcNumEmit * colorAvg(emap.partFlux) / |
| 487 |
srcFlux [srcIdx]; |
| 488 |
partEmitCnt = (unsigned long)partNumEmit; |
| 489 |
|
| 490 |
/* Probabilistically account for fractional photons */ |
| 491 |
if (pmapRandom(cntState) < partNumEmit - partEmitCnt) |
| 492 |
partEmitCnt++; |
| 493 |
|
| 494 |
/* Update local and shared global emission counter */ |
| 495 |
photonCnt [PHOTONCNT_NUMEMIT(srcIdx)] += partEmitCnt; |
| 496 |
localNumEmitted += partEmitCnt; |
| 497 |
|
| 498 |
/* Integer counter avoids FP rounding errors during |
| 499 |
* iteration */ |
| 500 |
while (partEmitCnt--) { |
| 501 |
RAY photonRay; |
| 502 |
|
| 503 |
/* Emit photon according to PDF (if any), allocate |
| 504 |
* associated primary ray, and trace through scene |
| 505 |
* until absorbed/leaked; emitPhoton() sets the |
| 506 |
* emitting light source index in photonRay */ |
| 507 |
emitPhoton(&emap, &photonRay); |
| 508 |
#if 1 |
| 509 |
if (emap.port) |
| 510 |
/* !!! PHOTON PORT REJECTION SAMPLING HACK: set |
| 511 |
* !!! photon port as fake hit object for |
| 512 |
* !!! primary ray to check for intersection in |
| 513 |
* !!! tracePhoton() */ |
| 514 |
photonRay.ro = emap.port -> so; |
| 515 |
#endif |
| 516 |
newPhotonPrimary(pm, &photonRay, primaryHeap[proc]); |
| 517 |
/* Set subprocess index in photonRay for post- |
| 518 |
* distrib primary index linearisation; this is |
| 519 |
* propagated with the primary index in photonRay |
| 520 |
* and set for photon hits by newPhoton() */ |
| 521 |
PMAP_SETRAYPROC(&photonRay, proc); |
| 522 |
tracePhoton(&photonRay); |
| 523 |
} |
| 524 |
|
| 525 |
/* Update shared global photon count */ |
| 526 |
photonCnt [PHOTONCNT_NUMPHOT] += pm -> numPhotons - |
| 527 |
lastNumPhotons; |
| 528 |
lastNumPhotons = pm -> numPhotons; |
| 529 |
#if !NIX |
| 530 |
/* Synchronous progress report on Windoze */ |
| 531 |
if (!proc && photonRepTime > 0 && |
| 532 |
time(NULL) >= repLastTime + photonRepTime) { |
| 533 |
unsigned s; |
| 534 |
repComplete = pm -> distribTarget * numProc; |
| 535 |
repProgress = photonCnt [PHOTONCNT_NUMPHOT]; |
| 536 |
|
| 537 |
for (repEmitted = 0, s = 0; s < nsources; s++) |
| 538 |
repEmitted += photonCnt [PHOTONCNT_NUMEMIT(s)]; |
| 539 |
|
| 540 |
pmapDistribReport(); |
| 541 |
} |
| 542 |
#endif |
| 543 |
} |
| 544 |
|
| 545 |
portCnt++; |
| 546 |
} while (portCnt < numPhotonPorts); |
| 547 |
|
| 548 |
if (pm -> numPhotons == srcNumDistrib) { |
| 549 |
/* Double predistrib factor in case no photons were stored |
| 550 |
* for this source and redo pass 1 */ |
| 551 |
srcPreDistrib *= 2; |
| 552 |
} |
| 553 |
else { |
| 554 |
/* Now do pass 2 */ |
| 555 |
passCnt++; |
| 556 |
} |
| 557 |
} |
| 558 |
} |
| 559 |
|
| 560 |
/* Flush heap buffa one final time to prevent data corruption */ |
| 561 |
flushPhotonHeap(pm); |
| 562 |
/* Flush final photon primary to primary heap file */ |
| 563 |
newPhotonPrimary(pm, NULL, primaryHeap [proc]); |
| 564 |
/* Heap files closed automatically on exit |
| 565 |
fclose(pm -> heap); |
| 566 |
fclose(primaryHeap [proc]); */ |
| 567 |
|
| 568 |
#ifdef DEBUG_PMAP |
| 569 |
sprintf(errmsg, "Proc %d total %ld photons\n", proc, |
| 570 |
pm -> numPhotons); |
| 571 |
eputs(errmsg); |
| 572 |
fflush(stderr); |
| 573 |
#endif |
| 574 |
|
| 575 |
#if NIX |
| 576 |
/* Terminate subprocess */ |
| 577 |
exit(0); |
| 578 |
#endif |
| 579 |
} |
| 580 |
else if (pid < 0) |
| 581 |
error(SYSTEM, "failed to fork subprocess in distribPhotonContrib"); |
| 582 |
} |
| 583 |
|
| 584 |
#if NIX |
| 585 |
/* PARENT PROCESS CONTINUES HERE */ |
| 586 |
#ifdef SIGCONT |
| 587 |
/* Enable progress report signal handler */ |
| 588 |
signal(SIGCONT, pmapDistribReport); |
| 589 |
#endif |
| 590 |
/* Wait for subprocesses to complete while reporting progress */ |
| 591 |
proc = numProc; |
| 592 |
while (proc) { |
| 593 |
while (waitpid(-1, &stat, WNOHANG) > 0) { |
| 594 |
/* Subprocess exited; check status */ |
| 595 |
if (!WIFEXITED(stat) || WEXITSTATUS(stat)) |
| 596 |
error(USER, "failed photon distribution"); |
| 597 |
|
| 598 |
--proc; |
| 599 |
} |
| 600 |
|
| 601 |
/* Nod off for a bit and update progress */ |
| 602 |
sleep(1); |
| 603 |
|
| 604 |
/* Asynchronous progress report from shared subprocess counters */ |
| 605 |
repComplete = pm -> distribTarget * numProc; |
| 606 |
repProgress = photonCnt [PHOTONCNT_NUMPHOT]; |
| 607 |
|
| 608 |
for (repEmitted = 0, srcIdx = 0; srcIdx < nsources; srcIdx++) |
| 609 |
repEmitted += photonCnt [PHOTONCNT_NUMEMIT(srcIdx)]; |
| 610 |
|
| 611 |
/* Get global photon count from shmem updated by subprocs */ |
| 612 |
pm -> numPhotons = photonCnt [PHOTONCNT_NUMPHOT]; |
| 613 |
|
| 614 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
| 615 |
pmapDistribReport(); |
| 616 |
#ifdef SIGCONT |
| 617 |
else signal(SIGCONT, pmapDistribReport); |
| 618 |
#endif |
| 619 |
} |
| 620 |
#endif /* NIX */ |
| 621 |
|
| 622 |
/* ================================================================ |
| 623 |
* POST-DISTRIBUTION - Set photon flux and build kd-tree, etc. |
| 624 |
* ================================================================ */ |
| 625 |
#ifdef SIGCONT |
| 626 |
/* Reset signal handler */ |
| 627 |
signal(SIGCONT, SIG_DFL); |
| 628 |
#endif |
| 629 |
free(emap.samples); |
| 630 |
|
| 631 |
if (!pm -> numPhotons) |
| 632 |
error(USER, "empty contribution photon map"); |
| 633 |
|
| 634 |
/* Load per-subprocess primary rays into pm -> primary array */ |
| 635 |
/* Dumb compilers apparently need the char** cast */ |
| 636 |
pm -> numPrimary = buildPrimaries(pm, primaryHeap, |
| 637 |
(char**)primaryHeapFname, |
| 638 |
primaryOfs, numProc); |
| 639 |
if (!pm -> numPrimary) |
| 640 |
error(INTERNAL, "no primary rays in contribution photon map"); |
| 641 |
|
| 642 |
/* Set photon flux per source */ |
| 643 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) |
| 644 |
srcFlux [srcIdx] /= photonCnt [PHOTONCNT_NUMEMIT(srcIdx)]; |
| 645 |
#if NIX |
| 646 |
/* Photon counters no longer needed, unmap shared memory */ |
| 647 |
munmap(photonCnt, sizeof(*photonCnt)); |
| 648 |
close(shmFile); |
| 649 |
unlink(shmFname); |
| 650 |
#else |
| 651 |
free(photonCnt); |
| 652 |
#endif |
| 653 |
|
| 654 |
if (verbose) { |
| 655 |
eputs("\nBuilding contribution photon map...\n"); |
| 656 |
#if NIX |
| 657 |
fflush(stderr); |
| 658 |
#endif |
| 659 |
} |
| 660 |
|
| 661 |
/* Build underlying data structure; heap is destroyed */ |
| 662 |
buildPhotonMap(pm, srcFlux, primaryOfs, numProc); |
| 663 |
|
| 664 |
/* Free per-subprocess primary heap files */ |
| 665 |
for (proc = 0; proc < numProc; proc++) |
| 666 |
free(primaryHeapFname [proc]); |
| 667 |
|
| 668 |
free(primaryHeapFname); |
| 669 |
free(primaryHeap); |
| 670 |
free(primaryOfs); |
| 671 |
|
| 672 |
if (verbose) |
| 673 |
eputs("\n"); |
| 674 |
} |
