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#ifndef lint |
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static const char RCSid[] = "$Id: pmap.c,v 2.12 2016/09/26 20:19:30 greg Exp $"; |
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#endif |
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|
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|
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/* |
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====================================================================== |
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Photon map main module |
9 |
|
10 |
Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) |
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(c) Fraunhofer Institute for Solar Energy Systems, |
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(c) Lucerne University of Applied Sciences and Arts, |
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supported by the Swiss National Science Foundation (SNSF, #147053) |
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====================================================================== |
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|
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$Id: pmap.c,v 2.12 2016/09/26 20:19:30 greg Exp $ |
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*/ |
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|
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|
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#include "pmap.h" |
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#include "pmapmat.h" |
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#include "pmapsrc.h" |
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#include "pmaprand.h" |
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#include "pmapio.h" |
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#include "pmapbias.h" |
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#include "pmapdiag.h" |
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#include "otypes.h" |
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#include <time.h> |
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#if NIX |
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#include <sys/stat.h> |
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#include <sys/mman.h> |
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#include <sys/wait.h> |
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#endif |
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|
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|
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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]) |
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savePhotonMap(pmaps [t], pmaps [t] -> fileName, argc, argv); |
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} |
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} |
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|
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|
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|
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static int photonParticipate (RAY *ray) |
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/* Trace photon through participating medium. Returns 1 if passed through, |
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or 0 if absorbed and $*%&ed. Analogon to rayparticipate(). */ |
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{ |
52 |
int i; |
53 |
RREAL cosTheta, cosPhi, du, dv; |
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const float cext = colorAvg(ray -> cext), |
55 |
albedo = colorAvg(ray -> albedo); |
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FVECT u, v; |
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COLOR cvext; |
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|
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/* Mean free distance until interaction with medium */ |
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ray -> rmax = -log(pmapRandom(mediumState)) / cext; |
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|
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while (!localhit(ray, &thescene)) { |
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setcolor(cvext, exp(-ray -> rmax * ray -> cext [0]), |
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exp(-ray -> rmax * ray -> cext [1]), |
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exp(-ray -> rmax * ray -> cext [2])); |
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|
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/* Modify ray color and normalise */ |
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multcolor(ray -> rcol, cvext); |
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colorNorm(ray -> rcol); |
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VCOPY(ray -> rorg, ray -> rop); |
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|
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if (albedo > FTINY && ray -> rlvl > 0) |
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/* Add to volume photon map */ |
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newPhoton(volumePmap, ray); |
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|
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/* Absorbed? */ |
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if (pmapRandom(rouletteState) > albedo) |
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return 0; |
79 |
|
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/* Colour bleeding without attenuation (?) */ |
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multcolor(ray -> rcol, ray -> albedo); |
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scalecolor(ray -> rcol, 1 / albedo); |
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|
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/* Scatter photon */ |
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cosTheta = ray -> gecc <= FTINY ? 2 * pmapRandom(scatterState) - 1 |
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: 1 / (2 * ray -> gecc) * |
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(1 + ray -> gecc * ray -> gecc - |
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(1 - ray -> gecc * ray -> gecc) / |
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(1 - ray -> gecc + 2 * ray -> gecc * |
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pmapRandom(scatterState))); |
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|
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cosPhi = cos(2 * PI * pmapRandom(scatterState)); |
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du = dv = sqrt(1 - cosTheta * cosTheta); /* sin(theta) */ |
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du *= cosPhi; |
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dv *= sqrt(1 - cosPhi * cosPhi); /* sin(phi) */ |
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|
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/* Get axes u & v perpendicular to photon direction */ |
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i = 0; |
99 |
do { |
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v [0] = v [1] = v [2] = 0; |
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v [i++] = 1; |
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fcross(u, v, ray -> rdir); |
103 |
} while (normalize(u) < FTINY); |
104 |
fcross(v, ray -> rdir, u); |
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|
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for (i = 0; i < 3; i++) |
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ray -> rdir [i] = du * u [i] + dv * v [i] + |
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cosTheta * ray -> rdir [i]; |
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ray -> rlvl++; |
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ray -> rmax = -log(pmapRandom(mediumState)) / cext; |
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} |
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|
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setcolor(cvext, exp(-ray -> rot * ray -> cext [0]), |
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exp(-ray -> rot * ray -> cext [1]), |
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exp(-ray -> rot * ray -> cext [2])); |
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|
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/* Modify ray color and normalise */ |
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multcolor(ray -> rcol, cvext); |
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colorNorm(ray -> rcol); |
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|
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/* Passed through medium */ |
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return 1; |
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} |
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|
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|
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|
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void tracePhoton (RAY *ray) |
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/* Follow photon as it bounces around... */ |
129 |
{ |
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long mod; |
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OBJREC *mat, *port = NULL; |
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|
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if (!ray -> parent) { |
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/* !!! PHOTON PORT REJECTION SAMPLING HACK: get photon port for |
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* !!! primary ray from ray -> ro, then reset the latter to NULL so |
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* !!! as not to interfere with localhit() */ |
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port = ray -> ro; |
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ray -> ro = NULL; |
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} |
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|
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if (ray -> rlvl > photonMaxBounce) { |
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#ifdef PMAP_RUNAWAY_WARN |
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error(WARNING, "runaway photon!"); |
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#endif |
145 |
return; |
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} |
147 |
|
148 |
if (colorAvg(ray -> cext) > FTINY && !photonParticipate(ray)) |
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return; |
150 |
|
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if (localhit(ray, &thescene)) { |
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mod = ray -> ro -> omod; |
153 |
|
154 |
if (port && ray -> ro != port) { |
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/* !!! PHOTON PORT REJECTION SAMPLING HACK !!! |
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* Terminate photon if emitted from port without intersecting it; |
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* this can happen when the port's partitions extend beyond its |
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* actual geometry, e.g. with polygons. Since the total flux |
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* relayed by the port is based on the (in this case) larger |
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* partition area, it is overestimated; terminating these photons |
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* constitutes rejection sampling and thereby compensates any bias |
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* incurred by the overestimated flux. */ |
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#ifdef PMAP_PORTREJECT_WARN |
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sprintf(errmsg, "photon outside port %s", ray -> ro -> oname); |
165 |
error(WARNING, errmsg); |
166 |
#endif |
167 |
return; |
168 |
} |
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|
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if ((ray -> clipset && inset(ray -> clipset, mod)) || mod == OVOID) { |
171 |
/* Transfer ray if modifier is VOID or clipped within antimatta */ |
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RAY tray; |
173 |
photonRay(ray, &tray, PMAP_XFER, NULL); |
174 |
tracePhoton(&tray); |
175 |
} |
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else { |
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/* Scatter for modifier material */ |
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mat = objptr(mod); |
179 |
photonScatter [mat -> otype] (mat, ray); |
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} |
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} |
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} |
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|
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|
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|
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static void preComputeGlobal (PhotonMap *pmap) |
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/* Precompute irradiance from global photons for final gathering for |
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a random subset of finalGather * pmap -> numPhotons photons, and builds |
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the photon map, discarding the original photons. */ |
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/* !!! NOTE: PRECOMPUTATION WITH OOC CURRENTLY WITHOUT CACHE !!! */ |
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{ |
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unsigned long i, numPreComp; |
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unsigned j; |
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PhotonIdx pIdx; |
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Photon photon; |
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RAY ray; |
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PhotonMap nuPmap; |
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|
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repComplete = numPreComp = finalGather * pmap -> numPhotons; |
200 |
|
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if (verbose) { |
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sprintf(errmsg, |
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"\nPrecomputing irradiance for %ld global photons\n", |
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numPreComp); |
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eputs(errmsg); |
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#if NIX |
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fflush(stderr); |
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#endif |
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} |
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|
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/* Copy photon map for precomputed photons */ |
212 |
memcpy(&nuPmap, pmap, sizeof(PhotonMap)); |
213 |
|
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/* Zero counters, init new heap and extents */ |
215 |
nuPmap.numPhotons = 0; |
216 |
initPhotonHeap(&nuPmap); |
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|
218 |
for (j = 0; j < 3; j++) { |
219 |
nuPmap.minPos [j] = FHUGE; |
220 |
nuPmap.maxPos [j] = -FHUGE; |
221 |
} |
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|
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/* Record start time, baby */ |
224 |
repStartTime = time(NULL); |
225 |
#ifdef SIGCONT |
226 |
signal(SIGCONT, pmapPreCompReport); |
227 |
#endif |
228 |
repProgress = 0; |
229 |
|
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photonRay(NULL, &ray, PRIMARY, NULL); |
231 |
ray.ro = NULL; |
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|
233 |
for (i = 0; i < numPreComp; i++) { |
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/* Get random photon from stratified distribution in source heap to |
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* avoid duplicates and clustering */ |
236 |
pIdx = firstPhoton(pmap) + |
237 |
(unsigned long)((i + pmapRandom(pmap -> randState)) / |
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finalGather); |
239 |
getPhoton(pmap, pIdx, &photon); |
240 |
|
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/* Init dummy photon ray with intersection at photon position */ |
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VCOPY(ray.rop, photon.pos); |
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for (j = 0; j < 3; j++) |
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ray.ron [j] = photon.norm [j] / 127.0; |
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|
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/* Get density estimate at photon position */ |
247 |
photonDensity(pmap, &ray, ray.rcol); |
248 |
|
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/* Append photon to new heap from ray */ |
250 |
newPhoton(&nuPmap, &ray); |
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|
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/* Update progress */ |
253 |
repProgress++; |
254 |
|
255 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
256 |
pmapPreCompReport(); |
257 |
#ifdef SIGCONT |
258 |
else signal(SIGCONT, pmapPreCompReport); |
259 |
#endif |
260 |
} |
261 |
|
262 |
/* Flush heap */ |
263 |
flushPhotonHeap(&nuPmap); |
264 |
|
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#ifdef SIGCONT |
266 |
signal(SIGCONT, SIG_DFL); |
267 |
#endif |
268 |
|
269 |
/* Trash original pmap, replace with precomputed one */ |
270 |
deletePhotons(pmap); |
271 |
memcpy(pmap, &nuPmap, sizeof(PhotonMap)); |
272 |
|
273 |
if (verbose) { |
274 |
eputs("\nRebuilding precomputed photon map\n"); |
275 |
#if NIX |
276 |
fflush(stderr); |
277 |
#endif |
278 |
} |
279 |
|
280 |
/* Rebuild underlying data structure, destroying heap */ |
281 |
buildPhotonMap(pmap, NULL, NULL, 1); |
282 |
} |
283 |
|
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|
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|
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typedef struct { |
287 |
unsigned long numPhotons [NUM_PMAP_TYPES], |
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numEmitted, numComplete; |
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} PhotonCnt; |
290 |
|
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|
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|
293 |
void distribPhotons (PhotonMap **pmaps, unsigned numProc) |
294 |
{ |
295 |
EmissionMap emap; |
296 |
char errmsg2 [128], shmFname [PMAP_TMPFNLEN]; |
297 |
unsigned t, srcIdx, proc; |
298 |
double totalFlux = 0; |
299 |
int shmFile, stat, pid; |
300 |
PhotonMap *pm; |
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PhotonCnt *photonCnt; |
302 |
|
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for (t = 0; t < NUM_PMAP_TYPES && !pmaps [t]; t++); |
304 |
|
305 |
if (t >= NUM_PMAP_TYPES) |
306 |
error(USER, "no photon maps defined in distribPhotons"); |
307 |
|
308 |
if (!nsources) |
309 |
error(USER, "no light sources in distribPhotons"); |
310 |
|
311 |
/* =================================================================== |
312 |
* INITIALISATION - Set up emission and scattering funcs |
313 |
* =================================================================== */ |
314 |
emap.samples = NULL; |
315 |
emap.maxPartitions = MAXSPART; |
316 |
emap.partitions = (unsigned char*)malloc(emap.maxPartitions >> 1); |
317 |
if (!emap.partitions) |
318 |
error(INTERNAL, "can't allocate source partitions in distribPhotons"); |
319 |
|
320 |
/* Initialise all defined photon maps */ |
321 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
322 |
if (pmaps [t]) { |
323 |
initPhotonMap(pmaps [t], t); |
324 |
/* Open photon heapfile */ |
325 |
initPhotonHeap(pmaps [t]); |
326 |
/* Per-subprocess target count */ |
327 |
pmaps [t] -> distribTarget /= numProc; |
328 |
|
329 |
if (!pmaps [t] -> distribTarget) |
330 |
error(INTERNAL, "no photons to distribute in distribPhotons"); |
331 |
} |
332 |
|
333 |
initPhotonEmissionFuncs(); |
334 |
initPhotonScatterFuncs(); |
335 |
|
336 |
/* Get photon ports if specified */ |
337 |
if (ambincl == 1) |
338 |
getPhotonPorts(); |
339 |
|
340 |
/* Get photon sensor modifiers */ |
341 |
getPhotonSensors(photonSensorList); |
342 |
|
343 |
#if NIX |
344 |
/* Set up shared mem for photon counters (zeroed by ftruncate) */ |
345 |
strcpy(shmFname, PMAP_TMPFNAME); |
346 |
shmFile = mkstemp(shmFname); |
347 |
|
348 |
if (shmFile < 0 || ftruncate(shmFile, sizeof(*photonCnt)) < 0) |
349 |
error(SYSTEM, "failed shared mem init in distribPhotons"); |
350 |
|
351 |
photonCnt = mmap(NULL, sizeof(*photonCnt), PROT_READ | PROT_WRITE, |
352 |
MAP_SHARED, shmFile, 0); |
353 |
|
354 |
if (photonCnt == MAP_FAILED) |
355 |
error(SYSTEM, "failed mapping shared memory in distribPhotons"); |
356 |
#else |
357 |
/* Allocate photon counters statically on Windoze */ |
358 |
if (!(photonCnt = malloc(sizeof(PhotonCnt)))) |
359 |
error(SYSTEM, "failed trivial malloc in distribPhotons"); |
360 |
photonCnt -> numEmitted = photonCnt -> numComplete = 0; |
361 |
#endif /* NIX */ |
362 |
|
363 |
if (verbose) { |
364 |
sprintf(errmsg, "\nIntegrating flux from %d sources", nsources); |
365 |
|
366 |
if (photonPorts) { |
367 |
sprintf(errmsg2, " via %d ports", numPhotonPorts); |
368 |
strcat(errmsg, errmsg2); |
369 |
} |
370 |
|
371 |
strcat(errmsg, "\n"); |
372 |
eputs(errmsg); |
373 |
} |
374 |
|
375 |
/* =================================================================== |
376 |
* FLUX INTEGRATION - Get total photon flux from light sources |
377 |
* =================================================================== */ |
378 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
379 |
unsigned portCnt = 0; |
380 |
emap.src = source + srcIdx; |
381 |
|
382 |
do { /* Need at least one iteration if no ports! */ |
383 |
emap.port = emap.src -> sflags & SDISTANT ? photonPorts + portCnt |
384 |
: NULL; |
385 |
photonPartition [emap.src -> so -> otype] (&emap); |
386 |
|
387 |
if (verbose) { |
388 |
sprintf(errmsg, "\tIntegrating flux from source %s ", |
389 |
source [srcIdx].so -> oname); |
390 |
|
391 |
if (emap.port) { |
392 |
sprintf(errmsg2, "via port %s ", |
393 |
photonPorts [portCnt].so -> oname); |
394 |
strcat(errmsg, errmsg2); |
395 |
} |
396 |
|
397 |
sprintf(errmsg2, "(%lu partitions)\n", emap.numPartitions); |
398 |
strcat(errmsg, errmsg2); |
399 |
eputs(errmsg); |
400 |
#if NIX |
401 |
fflush(stderr); |
402 |
#endif |
403 |
} |
404 |
|
405 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
406 |
emap.partitionCnt++) { |
407 |
initPhotonEmission(&emap, pdfSamples); |
408 |
totalFlux += colorAvg(emap.partFlux); |
409 |
} |
410 |
|
411 |
portCnt++; |
412 |
} while (portCnt < numPhotonPorts); |
413 |
} |
414 |
|
415 |
if (totalFlux < FTINY) |
416 |
error(USER, "zero flux from light sources"); |
417 |
|
418 |
/* Record start time for progress reports */ |
419 |
repStartTime = time(NULL); |
420 |
|
421 |
if (verbose) { |
422 |
sprintf(errmsg, "\nPhoton distribution @ %d procs\n", numProc); |
423 |
eputs(errmsg); |
424 |
} |
425 |
|
426 |
/* MAIN LOOP */ |
427 |
for (proc = 0; proc < numProc; proc++) { |
428 |
#if NIX |
429 |
if (!(pid = fork())) { |
430 |
/* SUBPROCESS ENTERS HERE; open and mmapped files inherited */ |
431 |
#else |
432 |
if (1) { |
433 |
/* No subprocess under Windoze */ |
434 |
#endif |
435 |
/* Local photon counters for this subprocess */ |
436 |
unsigned passCnt = 0, prePassCnt = 0; |
437 |
unsigned long lastNumPhotons [NUM_PMAP_TYPES]; |
438 |
unsigned long localNumEmitted = 0; /* Num photons emitted by this |
439 |
subprocess alone */ |
440 |
|
441 |
/* Seed RNGs from PID for decorellated photon distribution */ |
442 |
pmapSeed(randSeed + proc, partState); |
443 |
pmapSeed(randSeed + (proc + 1) % numProc, emitState); |
444 |
pmapSeed(randSeed + (proc + 2) % numProc, cntState); |
445 |
pmapSeed(randSeed + (proc + 3) % numProc, mediumState); |
446 |
pmapSeed(randSeed + (proc + 4) % numProc, scatterState); |
447 |
pmapSeed(randSeed + (proc + 5) % numProc, rouletteState); |
448 |
|
449 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
450 |
lastNumPhotons [t] = 0; |
451 |
|
452 |
/* ============================================================= |
453 |
* 2-PASS PHOTON DISTRIBUTION |
454 |
* Pass 1 (pre): emit fraction of target photon count |
455 |
* Pass 2 (main): based on outcome of pass 1, estimate remaining |
456 |
* number of photons to emit to approximate target |
457 |
* count |
458 |
* ============================================================= */ |
459 |
do { |
460 |
double numEmit; |
461 |
|
462 |
if (!passCnt) { |
463 |
/* INIT PASS 1 */ |
464 |
/* Skip if no photons contributed after sufficient |
465 |
* iterations; make it clear to user which photon maps are |
466 |
* missing so (s)he can check geometry and materials */ |
467 |
if (++prePassCnt > maxPreDistrib) { |
468 |
sprintf(errmsg, "proc %d: too many prepasses", proc); |
469 |
|
470 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
471 |
if (pmaps [t] && !pmaps [t] -> numPhotons) { |
472 |
sprintf(errmsg2, ", no %s photons stored", |
473 |
pmapName [t]); |
474 |
strcat(errmsg, errmsg2); |
475 |
} |
476 |
|
477 |
error(USER, errmsg); |
478 |
break; |
479 |
} |
480 |
|
481 |
/* Num to emit is fraction of minimum target count */ |
482 |
numEmit = FHUGE; |
483 |
|
484 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
485 |
if (pmaps [t]) |
486 |
numEmit = min(pmaps [t] -> distribTarget, numEmit); |
487 |
|
488 |
numEmit *= preDistrib; |
489 |
} |
490 |
else { |
491 |
/* INIT PASS 2 */ |
492 |
/* Based on the outcome of the predistribution we can now |
493 |
* estimate how many more photons we have to emit for each |
494 |
* photon map to meet its respective target count. This |
495 |
* value is clamped to 0 in case the target has already been |
496 |
* exceeded in the pass 1. */ |
497 |
double maxDistribRatio = 0; |
498 |
|
499 |
/* Set the distribution ratio for each map; this indicates |
500 |
* how many photons of each respective type are stored per |
501 |
* emitted photon, and is used as probability for storing a |
502 |
* photon by newPhoton(). Since this biases the photon |
503 |
* density, newPhoton() promotes the flux of stored photons |
504 |
* to compensate. */ |
505 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
506 |
if ((pm = pmaps [t])) { |
507 |
pm -> distribRatio = (double)pm -> distribTarget / |
508 |
pm -> numPhotons - 1; |
509 |
|
510 |
/* Check if photon map "overflowed", i.e. exceeded its |
511 |
* target count in the prepass; correcting the photon |
512 |
* flux via the distribution ratio is no longer |
513 |
* possible, as no more photons of this type will be |
514 |
* stored, so notify the user rather than deliver |
515 |
* incorrect results. In future we should handle this |
516 |
* more intelligently by using the photonFlux in each |
517 |
* photon map to individually correct the flux after |
518 |
* distribution. */ |
519 |
if (pm -> distribRatio <= FTINY) { |
520 |
sprintf(errmsg, "%s photon map overflow in " |
521 |
"prepass, reduce -apD", pmapName [t]); |
522 |
error(INTERNAL, errmsg); |
523 |
} |
524 |
|
525 |
maxDistribRatio = max(pm -> distribRatio, |
526 |
maxDistribRatio); |
527 |
} |
528 |
|
529 |
/* Normalise distribution ratios and calculate number of |
530 |
* photons to emit in main pass */ |
531 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
532 |
if ((pm = pmaps [t])) |
533 |
pm -> distribRatio /= maxDistribRatio; |
534 |
|
535 |
if ((numEmit = localNumEmitted * maxDistribRatio) < FTINY) |
536 |
/* No photons left to distribute in main pass */ |
537 |
break; |
538 |
} |
539 |
|
540 |
/* Update shared completion counter for progreport by parent */ |
541 |
photonCnt -> numComplete += numEmit; |
542 |
|
543 |
/* PHOTON DISTRIBUTION LOOP */ |
544 |
for (srcIdx = 0; srcIdx < nsources; srcIdx++) { |
545 |
unsigned portCnt = 0; |
546 |
emap.src = source + srcIdx; |
547 |
|
548 |
do { /* Need at least one iteration if no ports! */ |
549 |
emap.port = emap.src -> sflags & SDISTANT |
550 |
? photonPorts + portCnt : NULL; |
551 |
photonPartition [emap.src -> so -> otype] (&emap); |
552 |
|
553 |
if (verbose && !proc) { |
554 |
/* Output from subproc 0 only to avoid race condition |
555 |
* on console I/O */ |
556 |
if (!passCnt) |
557 |
sprintf(errmsg, "\tPREPASS %d on source %s ", |
558 |
prePassCnt, source [srcIdx].so -> oname); |
559 |
else |
560 |
sprintf(errmsg, "\tMAIN PASS on source %s ", |
561 |
source [srcIdx].so -> oname); |
562 |
|
563 |
if (emap.port) { |
564 |
sprintf(errmsg2, "via port %s ", |
565 |
photonPorts [portCnt].so -> oname); |
566 |
strcat(errmsg, errmsg2); |
567 |
} |
568 |
|
569 |
sprintf(errmsg2, "(%lu partitions)\n", |
570 |
emap.numPartitions); |
571 |
strcat(errmsg, errmsg2); |
572 |
eputs(errmsg); |
573 |
#if NIX |
574 |
fflush(stderr); |
575 |
#endif |
576 |
} |
577 |
|
578 |
for (emap.partitionCnt = 0; emap.partitionCnt < emap.numPartitions; |
579 |
emap.partitionCnt++) { |
580 |
double partNumEmit; |
581 |
unsigned long partEmitCnt; |
582 |
|
583 |
/* Get photon origin within current source partishunn |
584 |
* and build emission map */ |
585 |
photonOrigin [emap.src -> so -> otype] (&emap); |
586 |
initPhotonEmission(&emap, pdfSamples); |
587 |
|
588 |
/* Number of photons to emit from ziss partishunn -- |
589 |
* proportional to flux; photon ray weight and scalar |
590 |
* flux are uniform (latter only varying in RGB). */ |
591 |
partNumEmit = numEmit * colorAvg(emap.partFlux) / |
592 |
totalFlux; |
593 |
partEmitCnt = (unsigned long)partNumEmit; |
594 |
|
595 |
/* Probabilistically account for fractional photons */ |
596 |
if (pmapRandom(cntState) < partNumEmit - partEmitCnt) |
597 |
partEmitCnt++; |
598 |
|
599 |
/* Update local and shared (global) emission counter */ |
600 |
photonCnt -> numEmitted += partEmitCnt; |
601 |
localNumEmitted += partEmitCnt; |
602 |
|
603 |
/* Integer counter avoids FP rounding errors during |
604 |
* iteration */ |
605 |
while (partEmitCnt--) { |
606 |
RAY photonRay; |
607 |
|
608 |
/* Emit photon based on PDF and trace through scene |
609 |
* until absorbed/leaked */ |
610 |
emitPhoton(&emap, &photonRay); |
611 |
#if 1 |
612 |
if (emap.port) |
613 |
/* !!! PHOTON PORT REJECTION SAMPLING HACK: set |
614 |
* !!! photon port as fake hit object for |
615 |
* !!! primary ray to check for intersection in |
616 |
* !!! tracePhoton() */ |
617 |
photonRay.ro = emap.port -> so; |
618 |
#endif |
619 |
tracePhoton(&photonRay); |
620 |
} |
621 |
|
622 |
/* Update shared global photon count for each pmap */ |
623 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
624 |
if (pmaps [t]) { |
625 |
photonCnt -> numPhotons [t] += |
626 |
pmaps [t] -> numPhotons - lastNumPhotons [t]; |
627 |
lastNumPhotons [t] = pmaps [t] -> numPhotons; |
628 |
} |
629 |
#if !NIX |
630 |
/* Synchronous progress report on Windoze */ |
631 |
if (!proc && photonRepTime > 0 && |
632 |
time(NULL) >= repLastTime + photonRepTime) { |
633 |
repEmitted = repProgress = photonCnt -> numEmitted; |
634 |
repComplete = photonCnt -> numComplete; |
635 |
pmapDistribReport(); |
636 |
} |
637 |
#endif |
638 |
} |
639 |
|
640 |
portCnt++; |
641 |
} while (portCnt < numPhotonPorts); |
642 |
} |
643 |
|
644 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
645 |
if (pmaps [t] && !pmaps [t] -> numPhotons) { |
646 |
/* Double preDistrib in case a photon map is empty and |
647 |
* redo pass 1 --> possibility of infinite loop for |
648 |
* pathological scenes (e.g. absorbing materials) */ |
649 |
preDistrib *= 2; |
650 |
break; |
651 |
} |
652 |
|
653 |
if (t >= NUM_PMAP_TYPES) |
654 |
/* No empty photon maps found; now do pass 2 */ |
655 |
passCnt++; |
656 |
} while (passCnt < 2); |
657 |
|
658 |
/* Flush heap buffa for every pmap one final time; |
659 |
* avoids potential data corruption! */ |
660 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
661 |
if (pmaps [t]) { |
662 |
flushPhotonHeap(pmaps [t]); |
663 |
/* Heap file closed automatically on exit |
664 |
fclose(pmaps [t] -> heap); */ |
665 |
#ifdef DEBUG_PMAP |
666 |
sprintf(errmsg, "Proc %d: total %ld photons\n", proc, |
667 |
pmaps [t] -> numPhotons); |
668 |
eputs(errmsg); |
669 |
#endif |
670 |
} |
671 |
#if NIX |
672 |
/* Terminate subprocess */ |
673 |
exit(0); |
674 |
#endif |
675 |
} |
676 |
else if (pid < 0) |
677 |
error(SYSTEM, "failed to fork subprocess in distribPhotons"); |
678 |
} |
679 |
|
680 |
#if NIX |
681 |
/* PARENT PROCESS CONTINUES HERE */ |
682 |
#ifdef SIGCONT |
683 |
/* Enable progress report signal handler */ |
684 |
signal(SIGCONT, pmapDistribReport); |
685 |
#endif |
686 |
/* Wait for subprocesses complete while reporting progress */ |
687 |
proc = numProc; |
688 |
while (proc) { |
689 |
while (waitpid(-1, &stat, WNOHANG) > 0) { |
690 |
/* Subprocess exited; check status */ |
691 |
if (!WIFEXITED(stat) || WEXITSTATUS(stat)) |
692 |
error(USER, "failed photon distribution"); |
693 |
|
694 |
--proc; |
695 |
} |
696 |
|
697 |
/* Nod off for a bit and update progress */ |
698 |
sleep(1); |
699 |
|
700 |
/* Asynchronous progress report from shared subprocess counters */ |
701 |
repEmitted = repProgress = photonCnt -> numEmitted; |
702 |
repComplete = photonCnt -> numComplete; |
703 |
|
704 |
repProgress = repComplete = 0; |
705 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
706 |
if ((pm = pmaps [t])) { |
707 |
/* Get global photon count from shmem updated by subprocs */ |
708 |
repProgress += pm -> numPhotons = photonCnt -> numPhotons [t]; |
709 |
repComplete += pm -> distribTarget; |
710 |
} |
711 |
repComplete *= numProc; |
712 |
|
713 |
if (photonRepTime > 0 && time(NULL) >= repLastTime + photonRepTime) |
714 |
pmapDistribReport(); |
715 |
#ifdef SIGCONT |
716 |
else signal(SIGCONT, pmapDistribReport); |
717 |
#endif |
718 |
} |
719 |
#endif /* NIX */ |
720 |
|
721 |
/* =================================================================== |
722 |
* POST-DISTRIBUTION - Set photon flux and build data struct for photon |
723 |
* storage, etc. |
724 |
* =================================================================== */ |
725 |
#ifdef SIGCONT |
726 |
/* Reset signal handler */ |
727 |
signal(SIGCONT, SIG_DFL); |
728 |
#endif |
729 |
free(emap.samples); |
730 |
|
731 |
/* Set photon flux */ |
732 |
totalFlux /= photonCnt -> numEmitted; |
733 |
#if NIX |
734 |
/* Photon counters no longer needed, unmap shared memory */ |
735 |
munmap(photonCnt, sizeof(*photonCnt)); |
736 |
close(shmFile); |
737 |
unlink(shmFname); |
738 |
#else |
739 |
free(photonCnt); |
740 |
#endif |
741 |
if (verbose) |
742 |
eputs("\n"); |
743 |
|
744 |
for (t = 0; t < NUM_PMAP_TYPES; t++) |
745 |
if (pmaps [t]) { |
746 |
if (verbose) { |
747 |
sprintf(errmsg, "Building %s photon map\n", pmapName [t]); |
748 |
eputs(errmsg); |
749 |
#if NIX |
750 |
fflush(stderr); |
751 |
#endif |
752 |
} |
753 |
|
754 |
/* Build underlying data structure; heap is destroyed */ |
755 |
buildPhotonMap(pmaps [t], &totalFlux, NULL, numProc); |
756 |
} |
757 |
|
758 |
/* Precompute photon irradiance if necessary */ |
759 |
if (preCompPmap) { |
760 |
if (verbose) |
761 |
eputs("\n"); |
762 |
preComputeGlobal(preCompPmap); |
763 |
} |
764 |
|
765 |
if (verbose) |
766 |
eputs("\n"); |
767 |
} |