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RadiancePmap/pmapdata.c
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#ifndef lint
static const char RCSid[] = "$Id: pmapdata.c,v 2.23 2021/04/14 11:26:25 rschregle Exp $";
#endif
/*
=========================================================================
Photon map types and high level 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,
supported by the German Research Foundation
(DFG LU-204/10-2, "Fassadenintegrierte Regelsysteme" (FARESYS))
(c) Lucerne University of Applied Sciences and Arts,
supported by the Swiss National Science Foundation
(SNSF #147053, "Daylight Redirecting Components")
(c) Tokyo University of Science,
supported by the JSPS Grants-in-Aid for Scientific Research
(KAKENHI JP19KK0115, "Three-Dimensional Light Flow")
==========================================================================
$Id: pmapdata.c,v 2.23 2021/04/14 11:26:25 rschregle Exp $
*/
#include "pmapdata.h"
#include "pmapdens.h"
#include "pmaprand.h"
#include "pmapmat.h"
#include "otypes.h"
#include "random.h"
PhotonMap *photonMaps [NUM_PMAP_TYPES] = {
NULL, NULL, NULL, NULL, NULL, NULL,
#ifdef PMAP_PHOTONFLOW
NULL
#endif
};
/* 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];
/* Callback to print photon attributes acc. to user defined format */
int (*printPhoton)(RAY *r, Photon *p, PhotonMap *pm);
/* PHOTON MAP BUILD ROUTINES ------------------------------------------ */
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;
#ifdef PMAP_PHOTONFLOW
/* Init path lookup table and its key buffer */
pmap -> pathLUT = NULL;
pmap -> pathLUTKeys = NULL;
pmap -> numPathLUTKeys = 0;
#endif
/* 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 alternative 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;
/* Ignore photon if modifier in/outside exclude/include set */
if (ambincl != -1 && ray -> ro &&
ambincl != inset(ambset, ray -> ro -> omod))
return -1;
if (pmapNumROI && pmapROI) {
unsigned inROI = 0;
FVECT photonDist;
/* Store photon if within a region of interest (for ze Ecksperts!)
Note size of spherical ROI is squared. */
for (i = 0; !inROI && i < pmapNumROI; i++) {
VSUB(photonDist, ray -> rop, pmapROI [i].pos);
inROI = (
PMAP_ROI_ISSPHERE(pmapROI + i)
? DOT(photonDist, photonDist) <= pmapROI [i].siz [0]
: fabs(photonDist [0]) <= pmapROI [i].siz [0] &&
fabs(photonDist [1]) <= pmapROI [i].siz [1] &&
fabs(photonDist [2]) <= pmapROI [i].siz [2]
);
}
if (!inROI)
return -1;
}
/* Adjust flux according to distribution ratio and ray weight */
copycolor(photonFlux, ray -> rcol);
#if 0
/* Factored out ray -> rweight as deprecated (?) for pmap, and infact
erroneously attenuates volume photon flux based on extinction,
which is already factored in by photonParticipate() */
scalecolor(photonFlux,
ray -> rweight / (pmap -> distribRatio ? pmap -> distribRatio
: 1));
#else
scalecolor(
photonFlux,
1.0 / (pmap -> distribRatio ? pmap -> distribRatio : 1)
);
#endif
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;
}
/* Set photon's path ID from ray and subprocess */
else {
photon.primary = ray -> rno;
photon.proc = PMAP_GETRAYPROC(ray);
}
/* 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++;
/* Print photon attributes */
if (printPhoton)
/* Non-const kludge */
printPhoton((RAY*)ray, &photon, pmap);
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;
}
/* PHOTON MAP SEARCH ROUTINES ------------------------------------------ */
/* 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;
/* XXX/NOTE: status returned by XXX_FindPhotons() is currently ignored;
if no photons are found, an empty queue is returned under the
assumption all photons are too distant to contribute significant
flux. */
#ifdef PMAP_PHOTONFLOW
if (isVolumePmap(pmap) && !isLightFlowPmap(pmap)) {
#else
if (isVolumePmap(pmap)) {
#endif
/* Search position is ray -> rorg for volume photons, since we have
no intersection point. Photon normals are ignored; these are
incident directions for the volume scattering func). */
#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 : "<null>");
#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 : "<null>");
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 {
/* Skip search radius reduction 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);
}
Photon *find1Photon (PhotonMap *pmap, const RAY* ray, Photon *photon)
{
/* Init (squared) search radius to avg photon dist to centre of gravity */
float maxDist2_0 = pmap -> CoGdist;
int found = 0;
#ifdef PMAP_LOOKUP_REDO
#define REDO 1
#else
#define REDO 0
#endif
do {
pmap -> maxDist2 = maxDist2_0;
#ifdef PMAP_OOC
found = OOC_Find1Photon(pmap, ray -> rop, ray -> ron, photon);
#else
found = kdT_Find1Photon(pmap, ray -> rop, ray -> ron, photon);
#endif
if (found < 0) {
/* Expand search radius to retry */
maxDist2_0 *= 2;
#ifdef PMAP_LOOKUP_WARN
sprintf(errmsg, "failed 1-NN photon lookup"
#ifdef PMAP_LOOKUP_REDO
", retrying with search radius %.2f", maxDist2_0
#endif
);
error(WARNING, errmsg);
#endif
}
} while (REDO && found < 0);
/* Return photon buffer containing valid photon, else NULL */
return found < 0 ? NULL : photon;
}
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
}
/* PHOTON MAP CLEANUP ROUTINES ------------------------------------------ */
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;
#ifdef PMAP_PHOTONFLOW
if (pmap -> pathLUT) {
lu_done(pmap -> pathLUT);
free(pmap -> pathLUT);
}
if (pmap -> pathLUTKeys) {
unsigned k;
for (k = 0; k < pmap->squeue.len + 1; free(pmap->pathLUTKeys [k++]));
free(pmap -> pathLUTKeys);
}
#endif
}
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