#ifndef lint static const char RCSid[] = "$Id: pmapdata.c,v 2.19 2018/03/20 19:55:33 rschregle Exp $"; #endif /* ========================================================================= Photon map types and interface to nearest neighbour lookups in underlying point cloud data structure. The default data structure is an in-core kd-tree (see pmapkdt.{h,c}). This can be overriden with the PMAP_OOC compiletime switch, which enables an out-of-core octree (see oococt.{h,c}). Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) (c) Fraunhofer Institute for Solar Energy Systems, (c) Lucerne University of Applied Sciences and Arts, supported by the Swiss National Science Foundation (SNSF, #147053) ========================================================================== $Id: pmapdata.c,v 2.19 2018/03/20 19:55:33 rschregle Exp $ */ #include "pmapdata.h" #include "pmaprand.h" #include "pmapmat.h" #include "otypes.h" #include "source.h" #include "rcontrib.h" #include "random.h" PhotonMap *photonMaps [NUM_PMAP_TYPES] = { NULL, NULL, NULL, NULL, NULL, NULL }; /* Include routines to handle underlying point cloud data structure */ #ifdef PMAP_OOC #include "pmapooc.c" #else #include "pmapkdt.c" #endif /* Ambient include/exclude set (from ambient.c) */ #ifndef MAXASET #define MAXASET 4095 #endif extern OBJECT ambset [MAXASET+1]; void initPhotonMap (PhotonMap *pmap, PhotonMapType t) /* Init photon map 'n' stuff... */ { if (!pmap) return; pmap -> numPhotons = 0; pmap -> biasCompHist = NULL; pmap -> maxPos [0] = pmap -> maxPos [1] = pmap -> maxPos [2] = -FHUGE; pmap -> minPos [0] = pmap -> minPos [1] = pmap -> minPos [2] = FHUGE; pmap -> minGathered = pmap -> maxGathered = pmap -> totalGathered = 0; pmap -> gatherTolerance = gatherTolerance; pmap -> minError = pmap -> maxError = pmap -> rmsError = 0; pmap -> numDensity = 0; pmap -> distribRatio = 1; pmap -> type = t; pmap -> squeue.node = NULL; pmap -> squeue.len = 0; /* Init local RNG state */ pmap -> randState [0] = 10243; pmap -> randState [1] = 39829; pmap -> randState [2] = 9433; pmapSeed(randSeed, pmap -> randState); /* Set up type-specific photon lookup callback */ pmap -> lookup = pmapLookup [t]; /* Mark primary photon ray as unused */ pmap -> lastPrimary.srcIdx = -1; pmap -> numPrimary = 0; pmap -> primaries = NULL; /* Init storage */ pmap -> heap = NULL; pmap -> heapBuf = NULL; pmap -> heapBufLen = 0; #ifdef PMAP_OOC OOC_Null(&pmap -> store); #else kdT_Null(&pmap -> store); #endif } void initPhotonHeap (PhotonMap *pmap) { int fdFlags; if (!pmap) error(INTERNAL, "undefined photon map in initPhotonHeap"); if (!pmap -> heap) { /* Open heap file */ mktemp(strcpy(pmap -> heapFname, PMAP_TMPFNAME)); if (!(pmap -> heap = fopen(pmap -> heapFname, "w+b"))) error(SYSTEM, "failed opening heap file in initPhotonHeap"); #ifdef F_SETFL /* XXX is there an alternate needed for Windows? */ fdFlags = fcntl(fileno(pmap -> heap), F_GETFL); fcntl(fileno(pmap -> heap), F_SETFL, fdFlags | O_APPEND); #endif/* ftruncate(fileno(pmap -> heap), 0); */ } } void flushPhotonHeap (PhotonMap *pmap) { int fd; const unsigned long len = pmap -> heapBufLen * sizeof(Photon); if (!pmap) error(INTERNAL, "undefined photon map in flushPhotonHeap"); if (!pmap -> heap || !pmap -> heapBuf) { /* Silently ignore undefined heap error(INTERNAL, "undefined heap in flushPhotonHeap"); */ return; } /* Atomically seek and write block to heap */ /* !!! Unbuffered I/O via pwrite() avoids potential race conditions * !!! and buffer corruption which can occur with lseek()/fseek() * !!! followed by write()/fwrite(). */ fd = fileno(pmap -> heap); #ifdef DEBUG_PMAP sprintf(errmsg, "Proc %d: flushing %ld photons from pos %ld\n", getpid(), pmap -> heapBufLen, lseek(fd, 0, SEEK_END) / sizeof(Photon)); eputs(errmsg); #endif /*if (pwrite(fd, pmap -> heapBuf, len, lseek(fd, 0, SEEK_END)) != len) */ if (write(fd, pmap -> heapBuf, len) != len) error(SYSTEM, "failed append to heap file in flushPhotonHeap"); #if NIX if (fsync(fd)) error(SYSTEM, "failed fsync in flushPhotonHeap"); #endif pmap -> heapBufLen = 0; } #ifdef DEBUG_PMAP static int checkPhotonHeap (FILE *file) /* Check heap for nonsensical or duplicate photons */ { Photon p, lastp; int i, dup; rewind(file); memset(&lastp, 0, sizeof(lastp)); while (fread(&p, sizeof(p), 1, file)) { dup = 1; for (i = 0; i <= 2; i++) { if (p.pos [i] < thescene.cuorg [i] || p.pos [i] > thescene.cuorg [i] + thescene.cusize) { sprintf(errmsg, "corrupt photon in heap at [%f, %f, %f]\n", p.pos [0], p.pos [1], p.pos [2]); error(WARNING, errmsg); } dup &= p.pos [i] == lastp.pos [i]; } if (dup) { sprintf(errmsg, "consecutive duplicate photon in heap at [%f, %f, %f]\n", p.pos [0], p.pos [1], p.pos [2]); error(WARNING, errmsg); } } return 0; } #endif int newPhoton (PhotonMap* pmap, const RAY* ray) { unsigned i; Photon photon; COLOR photonFlux; /* Account for distribution ratio */ if (!pmap || pmapRandom(pmap -> randState) > pmap -> distribRatio) return -1; /* Don't store on sources */ if (ray -> robj > -1 && islight(objptr(ray -> ro -> omod) -> otype)) return -1; /* if modifier in include/exclude set */ if (ambincl != -1 && ray -> ro && ambincl != inset(ambset, ray -> ro -> omod)) return -1; if (pmapNumROI && pmapROI) { unsigned inROI = 0; /* Store photon if within a region of interest (for ze Ecksperts!) */ for (i = 0; !inROI && i < pmapNumROI; i++) inROI = (ray -> rop [0] >= pmapROI [i].min [0] && ray -> rop [0] <= pmapROI [i].max [0] && ray -> rop [1] >= pmapROI [i].min [1] && ray -> rop [1] <= pmapROI [i].max [1] && ray -> rop [2] >= pmapROI [i].min [2] && ray -> rop [2] <= pmapROI [i].max [2]); if (!inROI) return -1; } /* Adjust flux according to distribution ratio and ray weight */ copycolor(photonFlux, ray -> rcol); scalecolor(photonFlux, ray -> rweight / (pmap -> distribRatio ? pmap -> distribRatio : 1)); setPhotonFlux(&photon, photonFlux); /* Set photon position and flags */ VCOPY(photon.pos, ray -> rop); photon.flags = 0; photon.caustic = PMAP_CAUSTICRAY(ray); /* Set contrib photon's primary ray and subprocess index (the latter * to linearise the primary ray indices after photon distribution is * complete). Also set primary ray's source index, thereby marking it * as used. */ if (isContribPmap(pmap)) { photon.primary = pmap -> numPrimary; photon.proc = PMAP_GETRAYPROC(ray); pmap -> lastPrimary.srcIdx = ray -> rsrc; } else photon.primary = 0; /* Set normal */ for (i = 0; i <= 2; i++) photon.norm [i] = 127.0 * (isVolumePmap(pmap) ? ray -> rdir [i] : ray -> ron [i]); if (!pmap -> heapBuf) { /* Lazily allocate heap buffa */ #if NIX /* Randomise buffa size to temporally decorellate flushes in * multiprocessing mode */ srandom(randSeed + getpid()); pmap -> heapBufSize = PMAP_HEAPBUFSIZE * (0.5 + frandom()); #else /* Randomisation disabled for single processes on WIN; also useful * for reproducability during debugging */ pmap -> heapBufSize = PMAP_HEAPBUFSIZE; #endif if (!(pmap -> heapBuf = calloc(pmap -> heapBufSize, sizeof(Photon)))) error(SYSTEM, "failed heap buffer allocation in newPhoton"); pmap -> heapBufLen = 0; } /* Photon initialised; now append to heap buffa */ memcpy(pmap -> heapBuf + pmap -> heapBufLen, &photon, sizeof(Photon)); if (++pmap -> heapBufLen >= pmap -> heapBufSize) /* Heap buffa full, flush to heap file */ flushPhotonHeap(pmap); pmap -> numPhotons++; return 0; } void buildPhotonMap (PhotonMap *pmap, double *photonFlux, PhotonPrimaryIdx *primaryOfs, unsigned nproc) { unsigned long n, nCheck = 0; unsigned i; Photon *p; COLOR flux; char nuHeapFname [sizeof(PMAP_TMPFNAME)]; FILE *nuHeap; /* Need double here to reduce summation errors */ double avgFlux [3] = {0, 0, 0}, CoG [3] = {0, 0, 0}, CoGdist = 0; FVECT d; if (!pmap) error(INTERNAL, "undefined photon map in buildPhotonMap"); /* Get number of photons from heapfile size */ if (fseek(pmap -> heap, 0, SEEK_END) < 0) error(SYSTEM, "failed seek to end of photon heap in buildPhotonMap"); pmap -> numPhotons = ftell(pmap -> heap) / sizeof(Photon); if (!pmap -> numPhotons) error(INTERNAL, "empty photon map in buildPhotonMap"); if (!pmap -> heap) error(INTERNAL, "no heap in buildPhotonMap"); #ifdef DEBUG_PMAP eputs("Checking photon heap consistency...\n"); checkPhotonHeap(pmap -> heap); sprintf(errmsg, "Heap contains %ld photons\n", pmap -> numPhotons); eputs(errmsg); #endif /* Allocate heap buffa */ if (!pmap -> heapBuf) { pmap -> heapBufSize = PMAP_HEAPBUFSIZE; pmap -> heapBuf = calloc(pmap -> heapBufSize, sizeof(Photon)); if (!pmap -> heapBuf) error(SYSTEM, "failed to allocate postprocessed photon heap in" "buildPhotonMap"); } /* We REALLY don't need yet another @%&*! heap just to hold the scaled * photons, but can't think of a quicker fix... */ mktemp(strcpy(nuHeapFname, PMAP_TMPFNAME)); if (!(nuHeap = fopen(nuHeapFname, "w+b"))) error(SYSTEM, "failed to open postprocessed photon heap in " "buildPhotonMap"); rewind(pmap -> heap); #ifdef DEBUG_PMAP eputs("Postprocessing photons...\n"); #endif while (!feof(pmap -> heap)) { #ifdef DEBUG_PMAP printf("Reading %lu at %lu... ", pmap -> heapBufSize, ftell(pmap->heap)); #endif pmap -> heapBufLen = fread(pmap -> heapBuf, sizeof(Photon), pmap -> heapBufSize, pmap -> heap); #ifdef DEBUG_PMAP printf("Got %lu\n", pmap -> heapBufLen); #endif if (ferror(pmap -> heap)) error(SYSTEM, "failed to read photon heap in buildPhotonMap"); for (n = pmap -> heapBufLen, p = pmap -> heapBuf; n; n--, p++) { /* Update min and max pos and set photon flux */ for (i = 0; i <= 2; i++) { if (p -> pos [i] < pmap -> minPos [i]) pmap -> minPos [i] = p -> pos [i]; else if (p -> pos [i] > pmap -> maxPos [i]) pmap -> maxPos [i] = p -> pos [i]; /* Update centre of gravity with photon position */ CoG [i] += p -> pos [i]; } if (primaryOfs) /* Linearise photon primary index from subprocess index using the * per-subprocess offsets in primaryOfs */ p -> primary += primaryOfs [p -> proc]; /* Scale photon's flux (hitherto normalised to 1 over RGB); in * case of a contrib photon map, this is done per light source, * and photonFlux is assumed to be an array */ getPhotonFlux(p, flux); if (photonFlux) { scalecolor(flux, photonFlux [isContribPmap(pmap) ? photonSrcIdx(pmap, p) : 0]); setPhotonFlux(p, flux); } /* Update average photon flux; need a double here */ addcolor(avgFlux, flux); } /* Write modified photons to new heap */ fwrite(pmap -> heapBuf, sizeof(Photon), pmap -> heapBufLen, nuHeap); if (ferror(nuHeap)) error(SYSTEM, "failed postprocessing photon flux in " "buildPhotonMap"); nCheck += pmap -> heapBufLen; } #ifdef DEBUG_PMAP if (nCheck < pmap -> numPhotons) error(INTERNAL, "truncated photon heap in buildPhotonMap"); #endif /* Finalise average photon flux */ scalecolor(avgFlux, 1.0 / pmap -> numPhotons); copycolor(pmap -> photonFlux, avgFlux); /* Average photon positions to get centre of gravity */ for (i = 0; i < 3; i++) pmap -> CoG [i] = CoG [i] /= pmap -> numPhotons; rewind(pmap -> heap); /* Compute average photon distance to centre of gravity */ while (!feof(pmap -> heap)) { pmap -> heapBufLen = fread(pmap -> heapBuf, sizeof(Photon), pmap -> heapBufSize, pmap -> heap); for (n = pmap -> heapBufLen, p = pmap -> heapBuf; n; n--, p++) { VSUB(d, p -> pos, CoG); CoGdist += DOT(d, d); } } pmap -> CoGdist = CoGdist /= pmap -> numPhotons; /* Swap heaps, discarding unscaled photons */ fclose(pmap -> heap); unlink(pmap -> heapFname); pmap -> heap = nuHeap; strcpy(pmap -> heapFname, nuHeapFname); #ifdef PMAP_OOC OOC_BuildPhotonMap(pmap, nproc); #else kdT_BuildPhotonMap(pmap); #endif /* Trash heap and its buffa */ free(pmap -> heapBuf); fclose(pmap -> heap); unlink(pmap -> heapFname); pmap -> heap = NULL; pmap -> heapBuf = NULL; } /* Dynamic max photon search radius increase and reduction factors */ #define PMAP_MAXDIST_INC 4 #define PMAP_MAXDIST_DEC 0.9 /* Num successful lookups before reducing in max search radius */ #define PMAP_MAXDIST_CNT 1000 /* Threshold below which we assume increasing max radius won't help */ #define PMAP_SHORT_LOOKUP_THRESH 1 /* Coefficient for adaptive maximum search radius */ #define PMAP_MAXDIST_COEFF 100 void findPhotons (PhotonMap* pmap, const RAY* ray) { int redo = 0; if (!pmap -> squeue.len) { /* Lazy init priority queue */ #ifdef PMAP_OOC OOC_InitFindPhotons(pmap); #else kdT_InitFindPhotons(pmap); #endif pmap -> minGathered = pmap -> maxGather; pmap -> maxGathered = pmap -> minGather; pmap -> totalGathered = 0; pmap -> numLookups = pmap -> numShortLookups = 0; pmap -> shortLookupPct = 0; pmap -> minError = FHUGE; pmap -> maxError = -FHUGE; pmap -> rmsError = 0; /* SQUARED max search radius limit is based on avg photon distance to * centre of gravity, unless fixed by user (maxDistFix > 0) */ pmap -> maxDist0 = pmap -> maxDist2Limit = maxDistFix > 0 ? maxDistFix * maxDistFix : PMAP_MAXDIST_COEFF * pmap -> squeue.len * pmap -> CoGdist / pmap -> numPhotons; } do { pmap -> squeue.tail = 0; pmap -> maxDist2 = pmap -> maxDist0; /* Search position is ray -> rorg for volume photons, since we have no intersection point. Normals are ignored -- these are incident directions). */ if (isVolumePmap(pmap)) { #ifdef PMAP_OOC OOC_FindPhotons(pmap, ray -> rorg, NULL); #else kdT_FindPhotons(pmap, ray -> rorg, NULL); #endif } else { #ifdef PMAP_OOC OOC_FindPhotons(pmap, ray -> rop, ray -> ron); #else kdT_FindPhotons(pmap, ray -> rop, ray -> ron); #endif } #ifdef PMAP_LOOKUP_INFO fprintf(stderr, "%d/%d %s photons found within radius %.3f " "at (%.2f,%.2f,%.2f) on %s\n", pmap -> squeue.tail, pmap -> squeue.len, pmapName [pmap -> type], sqrt(pmap -> maxDist2), ray -> rop [0], ray -> rop [1], ray -> rop [2], ray -> ro ? ray -> ro -> oname : ""); #endif if (pmap -> squeue.tail < pmap -> squeue.len * pmap -> gatherTolerance) { /* Short lookup; too few photons found */ if (pmap -> squeue.tail > PMAP_SHORT_LOOKUP_THRESH) { /* Ignore short lookups which return fewer than * PMAP_SHORT_LOOKUP_THRESH photons under the assumption there * really are no photons in the vicinity, and increasing the max * search radius therefore won't help */ #ifdef PMAP_LOOKUP_WARN sprintf(errmsg, "%d/%d %s photons found at (%.2f,%.2f,%.2f) on %s", pmap -> squeue.tail, pmap -> squeue.len, pmapName [pmap -> type], ray -> rop [0], ray -> rop [1], ray -> rop [2], ray -> ro ? ray -> ro -> oname : ""); error(WARNING, errmsg); #endif /* Bail out after warning if maxDist is fixed */ if (maxDistFix > 0) return; if (pmap -> maxDist0 < pmap -> maxDist2Limit) { /* Increase max search radius if below limit & redo search */ pmap -> maxDist0 *= PMAP_MAXDIST_INC; #ifdef PMAP_LOOKUP_REDO redo = 1; #endif #ifdef PMAP_LOOKUP_WARN sprintf(errmsg, redo ? "restarting photon lookup with max radius %.1e" : "max photon lookup radius adjusted to %.1e", pmap -> maxDist0); error(WARNING, errmsg); #endif } #ifdef PMAP_LOOKUP_REDO else { sprintf(errmsg, "max photon lookup radius clamped to %.1e", pmap -> maxDist0); error(WARNING, errmsg); } #endif } /* Reset successful lookup counter */ pmap -> numLookups = 0; } else { /* Bail out after warning if maxDist is fixed */ if (maxDistFix > 0) return; /* Increment successful lookup counter and reduce max search radius if * wraparound */ pmap -> numLookups = (pmap -> numLookups + 1) % PMAP_MAXDIST_CNT; if (!pmap -> numLookups) pmap -> maxDist0 *= PMAP_MAXDIST_DEC; redo = 0; } } while (redo); } void find1Photon (PhotonMap *pmap, const RAY* ray, Photon *photon) { pmap -> maxDist2 = thescene.cusize; /* ? */ #ifdef PMAP_OOC OOC_Find1Photon(pmap, ray -> rop, ray -> ron, photon); #else kdT_Find1Photon(pmap, ray -> rop, ray -> ron, photon); #endif } void getPhoton (PhotonMap *pmap, PhotonIdx idx, Photon *photon) { #ifdef PMAP_OOC if (OOC_GetPhoton(pmap, idx, photon)) #else if (kdT_GetPhoton(pmap, idx, photon)) #endif error(INTERNAL, "failed photon lookup"); } Photon *getNearestPhoton (const PhotonSearchQueue *squeue, PhotonIdx idx) { #ifdef PMAP_OOC return OOC_GetNearestPhoton(squeue, idx); #else return kdT_GetNearestPhoton(squeue, idx); #endif } PhotonIdx firstPhoton (const PhotonMap *pmap) { #ifdef PMAP_OOC return OOC_FirstPhoton(pmap); #else return kdT_FirstPhoton(pmap); #endif } void deletePhotons (PhotonMap* pmap) { #ifdef PMAP_OOC OOC_Delete(&pmap -> store); #else kdT_Delete(&pmap -> store); #endif free(pmap -> squeue.node); free(pmap -> biasCompHist); pmap -> numPhotons = pmap -> minGather = pmap -> maxGather = pmap -> squeue.len = pmap -> squeue.tail = 0; }