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greg |
2.7 |
#ifndef lint
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rschregle |
2.13 |
static const char RCSid[] = "$Id: pmapsrc.c,v 4.18 2015/10/30 19:50:12 taschreg Exp taschreg $";
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greg |
2.7 |
#endif
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greg |
2.1 |
/*
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==================================================================
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Photon map support routines for emission from light sources
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Roland Schregle (roland.schregle@{hslu.ch, gmail.com})
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(c) Fraunhofer Institute for Solar Energy Systems,
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rschregle |
2.3 |
(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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greg |
2.1 |
==================================================================
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greg |
2.8 |
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greg |
2.1 |
*/
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#include "pmapsrc.h"
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#include "pmap.h"
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#include "pmaprand.h"
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#include "otypes.h"
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SRCREC *photonPorts = NULL; /* Photon port list */
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unsigned numPhotonPorts = 0;
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void (*photonPartition [NUMOTYPE]) (EmissionMap*);
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void (*photonOrigin [NUMOTYPE]) (EmissionMap*);
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extern OBJECT ambset [];
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static int flatPhotonPartition2 (EmissionMap* emap, unsigned long mp,
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FVECT cent, FVECT u, FVECT v,
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double du2, double dv2)
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/* Recursive part of flatPhotonPartition(..) */
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{
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FVECT newct, newax;
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unsigned long npl, npu;
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if (mp > emap -> maxPartitions) {
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/* Enlarge partition array */
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emap -> maxPartitions <<= 1;
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emap -> partitions = (unsigned char*)realloc(emap -> partitions,
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emap -> maxPartitions >> 1);
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if (!emap -> partitions)
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error(USER, "can't allocate source partitions");
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greg |
2.2 |
memset(emap -> partitions + (emap -> maxPartitions >> 2), 0,
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emap -> maxPartitions >> 2);
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greg |
2.1 |
}
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if (du2 * dv2 <= 1) { /* hit limit? */
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setpart(emap -> partitions, emap -> partitionCnt, S0);
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emap -> partitionCnt++;
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return 1;
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}
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if (du2 > dv2) { /* subdivide in U */
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setpart(emap -> partitions, emap -> partitionCnt, SU);
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emap -> partitionCnt++;
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newax [0] = 0.5 * u [0];
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newax [1] = 0.5 * u [1];
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newax [2] = 0.5 * u [2];
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u = newax;
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du2 *= 0.25;
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}
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else { /* subdivide in V */
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setpart(emap -> partitions, emap -> partitionCnt, SV);
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emap -> partitionCnt++;
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newax [0] = 0.5 * v [0];
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newax [1] = 0.5 * v [1];
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newax [2] = 0.5 * v [2];
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v = newax;
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dv2 *= 0.25;
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}
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/* lower half */
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newct [0] = cent [0] - newax [0];
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newct [1] = cent [1] - newax [1];
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newct [2] = cent [2] - newax [2];
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npl = flatPhotonPartition2(emap, mp << 1, newct, u, v, du2, dv2);
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/* upper half */
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newct [0] = cent [0] + newax [0];
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newct [1] = cent [1] + newax [1];
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newct [2] = cent [2] + newax [2];
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npu = flatPhotonPartition2(emap, mp << 1, newct, u, v, du2, dv2);
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/* return total */
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return npl + npu;
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}
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static void flatPhotonPartition (EmissionMap* emap)
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/* Partition flat source for photon emission */
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{
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RREAL *vp;
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double du2, dv2;
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greg |
2.2 |
memset(emap -> partitions, 0, emap -> maxPartitions >> 1);
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greg |
2.1 |
emap -> partArea = srcsizerat * thescene.cusize;
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emap -> partArea *= emap -> partArea;
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vp = emap -> src -> ss [SU];
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du2 = DOT(vp, vp) / emap -> partArea;
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vp = emap -> src -> ss [SV];
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dv2 = DOT(vp, vp) / emap -> partArea;
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emap -> partitionCnt = 0;
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emap -> numPartitions = flatPhotonPartition2(emap, 1, emap -> src -> sloc,
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emap -> src -> ss [SU],
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emap -> src -> ss [SV],
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du2, dv2);
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emap -> partitionCnt = 0;
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emap -> partArea = emap -> src -> ss2 / emap -> numPartitions;
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}
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static void sourcePhotonPartition (EmissionMap* emap)
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/* Partition scene cube faces or photon port for photon emission from
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distant source */
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{
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if (emap -> port) {
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/* Partition photon port */
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SRCREC *src = emap -> src;
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emap -> src = emap -> port;
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photonPartition [emap -> src -> so -> otype] (emap);
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emap -> src = src;
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}
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else {
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/* No photon ports defined, so partition scene cube faces */
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greg |
2.2 |
memset(emap -> partitions, 0, emap -> maxPartitions >> 1);
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greg |
2.1 |
setpart(emap -> partitions, 0, S0);
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emap -> partitionCnt = 0;
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emap -> numPartitions = 1 / srcsizerat;
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emap -> numPartitions *= emap -> numPartitions;
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emap -> partArea = sqr(thescene.cusize) / emap -> numPartitions;
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emap -> numPartitions *= 6;
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}
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}
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static void spherePhotonPartition (EmissionMap* emap)
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/* Partition spherical source into equal solid angles using uniform
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mapping for photon emission */
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{
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unsigned numTheta, numPhi;
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greg |
2.2 |
memset(emap -> partitions, 0, emap -> maxPartitions >> 1);
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greg |
2.1 |
setpart(emap -> partitions, 0, S0);
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emap -> partArea = 4 * PI * sqr(emap -> src -> srad);
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emap -> numPartitions = emap -> partArea /
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sqr(srcsizerat * thescene.cusize);
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numTheta = max(sqrt(2 * emap -> numPartitions / PI) + 0.5, 1);
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numPhi = 0.5 * PI * numTheta + 0.5;
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emap -> numPartitions = (unsigned long)numTheta * numPhi;
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emap -> partitionCnt = 0;
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emap -> partArea /= emap -> numPartitions;
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}
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static int cylPhotonPartition2 (EmissionMap* emap, unsigned long mp,
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FVECT cent, FVECT axis, double d2)
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/* Recursive part of cyPhotonPartition(..) */
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{
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FVECT newct, newax;
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unsigned long npl, npu;
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if (mp > emap -> maxPartitions) {
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/* Enlarge partition array */
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emap -> maxPartitions <<= 1;
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emap -> partitions = (unsigned char*)realloc(emap -> partitions,
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emap -> maxPartitions >> 1);
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if (!emap -> partitions)
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error(USER, "can't allocate source partitions");
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greg |
2.2 |
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memset(emap -> partitions + (emap -> maxPartitions >> 2), 0,
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greg |
2.1 |
emap -> maxPartitions >> 2);
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}
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if (d2 <= 1) {
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/* hit limit? */
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setpart(emap -> partitions, emap -> partitionCnt, S0);
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emap -> partitionCnt++;
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return 1;
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}
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/* subdivide */
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setpart(emap -> partitions, emap -> partitionCnt, SU);
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emap -> partitionCnt++;
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newax [0] = 0.5 * axis [0];
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newax [1] = 0.5 * axis [1];
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newax [2] = 0.5 * axis [2];
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d2 *= 0.25;
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/* lower half */
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newct [0] = cent [0] - newax [0];
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newct [1] = cent [1] - newax [1];
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newct [2] = cent [2] - newax [2];
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npl = cylPhotonPartition2(emap, mp << 1, newct, newax, d2);
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/* upper half */
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newct [0] = cent [0] + newax [0];
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newct [1] = cent [1] + newax [1];
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newct [2] = cent [2] + newax [2];
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npu = cylPhotonPartition2(emap, mp << 1, newct, newax, d2);
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/* return total */
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return npl + npu;
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}
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| 224 |
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static void cylPhotonPartition (EmissionMap* emap)
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| 225 |
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/* Partition cylindrical source for photon emission */
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| 226 |
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{
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| 227 |
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double d2;
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| 228 |
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| 229 |
greg |
2.2 |
memset(emap -> partitions, 0, emap -> maxPartitions >> 1);
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| 230 |
greg |
2.1 |
d2 = srcsizerat * thescene.cusize;
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d2 = PI * emap -> src -> ss2 / (2 * emap -> src -> srad * sqr(d2));
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d2 *= d2 * DOT(emap -> src -> ss [SU], emap -> src -> ss [SU]);
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| 234 |
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emap -> partitionCnt = 0;
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emap -> numPartitions = cylPhotonPartition2(emap, 1, emap -> src -> sloc,
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| 236 |
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emap -> src -> ss [SU], d2);
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emap -> partitionCnt = 0;
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| 238 |
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emap -> partArea = PI * emap -> src -> ss2 / emap -> numPartitions;
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}
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static void flatPhotonOrigin (EmissionMap* emap)
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/* Init emission map with photon origin and associated surface axes on
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| 245 |
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flat light source surface. Also sets source aperture and sampling
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| 246 |
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hemisphere axes at origin */
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| 247 |
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{
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| 248 |
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int i, cent[3], size[3], parr[2];
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| 249 |
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FVECT vpos;
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| 250 |
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| 251 |
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cent [0] = cent [1] = cent [2] = 0;
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| 252 |
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size [0] = size [1] = size [2] = emap -> maxPartitions;
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| 253 |
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parr [0] = 0;
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| 254 |
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parr [1] = emap -> partitionCnt;
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| 255 |
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| 256 |
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if (!skipparts(cent, size, parr, emap -> partitions))
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| 257 |
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error(CONSISTENCY, "bad source partition in flatPhotonOrigin");
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| 258 |
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| 259 |
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vpos [0] = (1 - 2 * pmapRandom(partState)) * size [0] /
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| 260 |
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emap -> maxPartitions;
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vpos [1] = (1 - 2 * pmapRandom(partState)) * size [1] /
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| 262 |
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emap -> maxPartitions;
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| 263 |
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vpos [2] = 0;
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| 264 |
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| 265 |
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for (i = 0; i < 3; i++)
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| 266 |
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vpos [i] += (double)cent [i] / emap -> maxPartitions;
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| 267 |
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| 268 |
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/* Get origin */
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| 269 |
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for (i = 0; i < 3; i++)
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| 270 |
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emap -> photonOrg [i] = emap -> src -> sloc [i] +
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| 271 |
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vpos [SU] * emap -> src -> ss [SU][i] +
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| 272 |
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vpos [SV] * emap -> src -> ss [SV][i] +
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| 273 |
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vpos [SW] * emap -> src -> ss [SW][i];
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| 274 |
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| 275 |
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/* Get surface axes */
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| 276 |
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VCOPY(emap -> us, emap -> src -> ss [SU]);
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| 277 |
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normalize(emap -> us);
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| 278 |
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VCOPY(emap -> ws, emap -> src -> ss [SW]);
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| 279 |
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| 280 |
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if (emap -> port)
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| 281 |
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/* Acts as a photon port; reverse normal as it points INSIDE per
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| 282 |
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* mkillum convention */
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| 283 |
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for (i = 0; i < 3; i++)
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| 284 |
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emap -> ws [i] = -emap -> ws [i];
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| 285 |
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| 286 |
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fcross(emap -> vs, emap -> ws, emap -> us);
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| 287 |
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| 288 |
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/* Get hemisphere axes & aperture */
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| 289 |
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if (emap -> src -> sflags & SSPOT) {
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| 290 |
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VCOPY(emap -> wh, emap -> src -> sl.s -> aim);
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| 291 |
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i = 0;
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| 292 |
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| 293 |
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do {
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| 294 |
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emap -> vh [0] = emap -> vh [1] = emap -> vh [2] = 0;
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| 295 |
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emap -> vh [i++] = 1;
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| 296 |
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fcross(emap -> uh, emap -> vh, emap -> wh);
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| 297 |
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} while (normalize(emap -> uh) < FTINY);
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| 298 |
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| 299 |
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fcross(emap -> vh, emap -> wh, emap -> uh);
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| 300 |
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emap -> cosThetaMax = 1 - emap -> src -> sl.s -> siz / (2 * PI);
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| 301 |
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}
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| 302 |
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| 303 |
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else {
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| 304 |
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VCOPY(emap -> uh, emap -> us);
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| 305 |
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VCOPY(emap -> vh, emap -> vs);
|
| 306 |
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VCOPY(emap -> wh, emap -> ws);
|
| 307 |
|
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emap -> cosThetaMax = 0;
|
| 308 |
|
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}
|
| 309 |
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}
|
| 310 |
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| 311 |
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| 312 |
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|
| 313 |
|
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static void spherePhotonOrigin (EmissionMap* emap)
|
| 314 |
|
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/* Init emission map with photon origin and associated surface axes on
|
| 315 |
|
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spherical light source. Also sets source aperture and sampling
|
| 316 |
|
|
hemisphere axes at origin */
|
| 317 |
|
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{
|
| 318 |
|
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int i = 0;
|
| 319 |
|
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unsigned numTheta, numPhi, t, p;
|
| 320 |
|
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RREAL cosTheta, sinTheta, phi;
|
| 321 |
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|
| 322 |
|
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/* Get current partition */
|
| 323 |
|
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numTheta = max(sqrt(2 * emap -> numPartitions / PI) + 0.5, 1);
|
| 324 |
|
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numPhi = 0.5 * PI * numTheta + 0.5;
|
| 325 |
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|
| 326 |
|
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t = emap -> partitionCnt / numPhi;
|
| 327 |
|
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p = emap -> partitionCnt - t * numPhi;
|
| 328 |
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|
| 329 |
|
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emap -> ws [2] = cosTheta = 1 - 2 * (t + pmapRandom(partState)) / numTheta;
|
| 330 |
|
|
sinTheta = sqrt(1 - sqr(cosTheta));
|
| 331 |
|
|
phi = 2 * PI * (p + pmapRandom(partState)) / numPhi;
|
| 332 |
|
|
emap -> ws [0] = cos(phi) * sinTheta;
|
| 333 |
|
|
emap -> ws [1] = sin(phi) * sinTheta;
|
| 334 |
|
|
|
| 335 |
|
|
if (emap -> port)
|
| 336 |
|
|
/* Acts as a photon port; reverse normal as it points INSIDE per
|
| 337 |
|
|
* mkillum convention */
|
| 338 |
|
|
for (i = 0; i < 3; i++)
|
| 339 |
|
|
emap -> ws [i] = -emap -> ws [i];
|
| 340 |
|
|
|
| 341 |
|
|
/* Get surface axes us & vs perpendicular to ws */
|
| 342 |
|
|
do {
|
| 343 |
|
|
emap -> vs [0] = emap -> vs [1] = emap -> vs [2] = 0;
|
| 344 |
|
|
emap -> vs [i++] = 1;
|
| 345 |
|
|
fcross(emap -> us, emap -> vs, emap -> ws);
|
| 346 |
|
|
} while (normalize(emap -> us) < FTINY);
|
| 347 |
|
|
|
| 348 |
|
|
fcross(emap -> vs, emap -> ws, emap -> us);
|
| 349 |
|
|
|
| 350 |
|
|
/* Get origin */
|
| 351 |
|
|
for (i = 0; i < 3; i++)
|
| 352 |
|
|
emap -> photonOrg [i] = emap -> src -> sloc [i] +
|
| 353 |
|
|
emap -> src -> srad * emap -> ws [i];
|
| 354 |
|
|
|
| 355 |
|
|
/* Get hemisphere axes & aperture */
|
| 356 |
|
|
if (emap -> src -> sflags & SSPOT) {
|
| 357 |
|
|
VCOPY(emap -> wh, emap -> src -> sl.s -> aim);
|
| 358 |
|
|
i = 0;
|
| 359 |
|
|
|
| 360 |
|
|
do {
|
| 361 |
|
|
emap -> vh [0] = emap -> vh [1] = emap -> vh [2] = 0;
|
| 362 |
|
|
emap -> vh [i++] = 1;
|
| 363 |
|
|
fcross(emap -> uh, emap -> vh, emap -> wh);
|
| 364 |
|
|
} while (normalize(emap -> uh) < FTINY);
|
| 365 |
|
|
|
| 366 |
|
|
fcross(emap -> vh, emap -> wh, emap -> uh);
|
| 367 |
|
|
emap -> cosThetaMax = 1 - emap -> src -> sl.s -> siz / (2 * PI);
|
| 368 |
|
|
}
|
| 369 |
|
|
|
| 370 |
|
|
else {
|
| 371 |
|
|
VCOPY(emap -> uh, emap -> us);
|
| 372 |
|
|
VCOPY(emap -> vh, emap -> vs);
|
| 373 |
|
|
VCOPY(emap -> wh, emap -> ws);
|
| 374 |
|
|
emap -> cosThetaMax = 0;
|
| 375 |
|
|
}
|
| 376 |
|
|
}
|
| 377 |
|
|
|
| 378 |
|
|
|
| 379 |
|
|
|
| 380 |
|
|
static void sourcePhotonOrigin (EmissionMap* emap)
|
| 381 |
|
|
/* Init emission map with photon origin and associated surface axes
|
| 382 |
|
|
on scene cube face for distant light source. Also sets source
|
| 383 |
|
|
aperture (solid angle) and sampling hemisphere axes at origin */
|
| 384 |
|
|
{
|
| 385 |
|
|
unsigned long i, partsPerDim, partsPerFace;
|
| 386 |
|
|
unsigned face;
|
| 387 |
|
|
RREAL du, dv;
|
| 388 |
|
|
|
| 389 |
|
|
if (emap -> port) {
|
| 390 |
|
|
/* Get origin on photon port */
|
| 391 |
|
|
SRCREC *src = emap -> src;
|
| 392 |
|
|
emap -> src = emap -> port;
|
| 393 |
|
|
photonOrigin [emap -> src -> so -> otype] (emap);
|
| 394 |
|
|
emap -> src = src;
|
| 395 |
|
|
}
|
| 396 |
|
|
|
| 397 |
|
|
else {
|
| 398 |
|
|
/* No ports defined, so get origin on scene cube face and SUFFA! */
|
| 399 |
|
|
/* Get current face from partition number */
|
| 400 |
|
|
partsPerDim = 1 / srcsizerat;
|
| 401 |
|
|
partsPerFace = sqr(partsPerDim);
|
| 402 |
|
|
face = emap -> partitionCnt / partsPerFace;
|
| 403 |
|
|
|
| 404 |
|
|
if (!(emap -> partitionCnt % partsPerFace)) {
|
| 405 |
|
|
/* Skipped to a new face; get its normal */
|
| 406 |
|
|
emap -> ws [0] = emap -> ws [1] = emap -> ws [2] = 0;
|
| 407 |
|
|
emap -> ws [face >> 1] = face & 1 ? 1 : -1;
|
| 408 |
|
|
|
| 409 |
|
|
/* Get surface axes us & vs perpendicular to ws */
|
| 410 |
|
|
face >>= 1;
|
| 411 |
|
|
emap -> vs [0] = emap -> vs [1] = emap -> vs [2] = 0;
|
| 412 |
|
|
emap -> vs [(face + (emap -> ws [face] > 0 ? 2 : 1)) % 3] = 1;
|
| 413 |
|
|
fcross(emap -> us, emap -> vs, emap -> ws);
|
| 414 |
|
|
}
|
| 415 |
|
|
|
| 416 |
|
|
/* Get jittered offsets within face from partition number
|
| 417 |
|
|
(in range [-0.5, 0.5]) */
|
| 418 |
|
|
i = emap -> partitionCnt % partsPerFace;
|
| 419 |
|
|
du = (i / partsPerDim + pmapRandom(partState)) / partsPerDim - 0.5;
|
| 420 |
|
|
dv = (i % partsPerDim + pmapRandom(partState)) / partsPerDim - 0.5;
|
| 421 |
|
|
|
| 422 |
|
|
/* Jittered destination point within partition */
|
| 423 |
|
|
for (i = 0; i < 3; i++)
|
| 424 |
|
|
emap -> photonOrg [i] = thescene.cuorg [i] +
|
| 425 |
|
|
thescene.cusize * (0.5 + du * emap -> us [i] +
|
| 426 |
|
|
dv * emap -> vs [i] +
|
| 427 |
|
|
0.5 * emap -> ws [i]);
|
| 428 |
|
|
}
|
| 429 |
|
|
|
| 430 |
|
|
/* Get hemisphere axes & aperture */
|
| 431 |
|
|
VCOPY(emap -> wh, emap -> src -> sloc);
|
| 432 |
|
|
i = 0;
|
| 433 |
|
|
|
| 434 |
|
|
do {
|
| 435 |
|
|
emap -> vh [0] = emap -> vh [1] = emap -> vh [2] = 0;
|
| 436 |
|
|
emap -> vh [i++] = 1;
|
| 437 |
|
|
fcross(emap -> uh, emap -> vh, emap -> wh);
|
| 438 |
|
|
} while (normalize(emap -> uh) < FTINY);
|
| 439 |
|
|
|
| 440 |
|
|
fcross(emap -> vh, emap -> wh, emap -> uh);
|
| 441 |
|
|
|
| 442 |
|
|
/* Get aperture */
|
| 443 |
|
|
emap -> cosThetaMax = 1 - emap -> src -> ss2 / (2 * PI);
|
| 444 |
|
|
emap -> cosThetaMax = min(1, max(-1, emap -> cosThetaMax));
|
| 445 |
|
|
}
|
| 446 |
|
|
|
| 447 |
|
|
|
| 448 |
|
|
|
| 449 |
|
|
static void cylPhotonOrigin (EmissionMap* emap)
|
| 450 |
|
|
/* Init emission map with photon origin and associated surface axes
|
| 451 |
|
|
on cylindrical light source surface. Also sets source aperture
|
| 452 |
|
|
and sampling hemisphere axes at origin */
|
| 453 |
|
|
{
|
| 454 |
|
|
int i, cent[3], size[3], parr[2];
|
| 455 |
|
|
FVECT v;
|
| 456 |
|
|
|
| 457 |
|
|
cent [0] = cent [1] = cent [2] = 0;
|
| 458 |
|
|
size [0] = size [1] = size [2] = emap -> maxPartitions;
|
| 459 |
|
|
parr [0] = 0;
|
| 460 |
|
|
parr [1] = emap -> partitionCnt;
|
| 461 |
|
|
|
| 462 |
|
|
if (!skipparts(cent, size, parr, emap -> partitions))
|
| 463 |
|
|
error(CONSISTENCY, "bad source partition in cylPhotonOrigin");
|
| 464 |
|
|
|
| 465 |
|
|
v [SU] = 0;
|
| 466 |
|
|
v [SV] = (1 - 2 * pmapRandom(partState)) * (double)size [1] /
|
| 467 |
|
|
emap -> maxPartitions;
|
| 468 |
|
|
v [SW] = (1 - 2 * pmapRandom(partState)) * (double)size [2] /
|
| 469 |
|
|
emap -> maxPartitions;
|
| 470 |
|
|
normalize(v);
|
| 471 |
|
|
v [SU] = (1 - 2 * pmapRandom(partState)) * (double)size [1] /
|
| 472 |
|
|
emap -> maxPartitions;
|
| 473 |
|
|
|
| 474 |
|
|
for (i = 0; i < 3; i++)
|
| 475 |
|
|
v [i] += (double)cent [i] / emap -> maxPartitions;
|
| 476 |
|
|
|
| 477 |
|
|
/* Get surface axes */
|
| 478 |
|
|
for (i = 0; i < 3; i++)
|
| 479 |
|
|
emap -> photonOrg [i] = emap -> ws [i] =
|
| 480 |
|
|
(v [SV] * emap -> src -> ss [SV][i] +
|
| 481 |
|
|
v [SW] * emap -> src -> ss [SW][i]) / 0.8559;
|
| 482 |
|
|
|
| 483 |
|
|
if (emap -> port)
|
| 484 |
|
|
/* Acts as a photon port; reverse normal as it points INSIDE per
|
| 485 |
|
|
* mkillum convention */
|
| 486 |
|
|
for (i = 0; i < 3; i++)
|
| 487 |
|
|
emap -> ws [i] = -emap -> ws [i];
|
| 488 |
|
|
|
| 489 |
|
|
normalize(emap -> ws);
|
| 490 |
|
|
VCOPY(emap -> us, emap -> src -> ss [SU]);
|
| 491 |
|
|
normalize(emap -> us);
|
| 492 |
|
|
fcross(emap -> vs, emap -> ws, emap -> us);
|
| 493 |
|
|
|
| 494 |
|
|
/* Get origin */
|
| 495 |
|
|
for (i = 0; i < 3; i++)
|
| 496 |
|
|
emap -> photonOrg [i] += v [SU] * emap -> src -> ss [SU][i] +
|
| 497 |
|
|
emap -> src -> sloc [i];
|
| 498 |
|
|
|
| 499 |
|
|
/* Get hemisphere axes & aperture */
|
| 500 |
|
|
if (emap -> src -> sflags & SSPOT) {
|
| 501 |
|
|
VCOPY(emap -> wh, emap -> src -> sl.s -> aim);
|
| 502 |
|
|
i = 0;
|
| 503 |
|
|
|
| 504 |
|
|
do {
|
| 505 |
|
|
emap -> vh [0] = emap -> vh [1] = emap -> vh [2] = 0;
|
| 506 |
|
|
emap -> vh [i++] = 1;
|
| 507 |
|
|
fcross(emap -> uh, emap -> vh, emap -> wh);
|
| 508 |
|
|
} while (normalize(emap -> uh) < FTINY);
|
| 509 |
|
|
|
| 510 |
|
|
fcross(emap -> vh, emap -> wh, emap -> uh);
|
| 511 |
|
|
emap -> cosThetaMax = 1 - emap -> src -> sl.s -> siz / (2 * PI);
|
| 512 |
|
|
}
|
| 513 |
|
|
|
| 514 |
|
|
else {
|
| 515 |
|
|
VCOPY(emap -> uh, emap -> us);
|
| 516 |
|
|
VCOPY(emap -> vh, emap -> vs);
|
| 517 |
|
|
VCOPY(emap -> wh, emap -> ws);
|
| 518 |
|
|
emap -> cosThetaMax = 0;
|
| 519 |
|
|
}
|
| 520 |
|
|
}
|
| 521 |
|
|
|
| 522 |
|
|
|
| 523 |
|
|
|
| 524 |
|
|
void getPhotonPorts ()
|
| 525 |
|
|
/* Find geometry declared as photon ports */
|
| 526 |
|
|
{
|
| 527 |
|
|
OBJECT i;
|
| 528 |
rschregle |
2.11 |
OBJREC *obj, *mat;
|
| 529 |
greg |
2.1 |
|
| 530 |
|
|
/* Check for missing port modifiers */
|
| 531 |
|
|
if (!ambset [0])
|
| 532 |
rschregle |
2.11 |
error(USER, "no photon ports");
|
| 533 |
greg |
2.1 |
|
| 534 |
|
|
for (i = 0; i < nobjects; i++) {
|
| 535 |
|
|
obj = objptr(i);
|
| 536 |
rschregle |
2.11 |
mat = findmaterial(obj);
|
| 537 |
greg |
2.1 |
|
| 538 |
rschregle |
2.10 |
/* Check if object is a surface and NOT a light source (duh) and
|
| 539 |
|
|
* resolve its material via any aliases, then check for inclusion in
|
| 540 |
|
|
* port modifier list */
|
| 541 |
rschregle |
2.12 |
if (issurface(obj -> otype) && mat && !islight(mat -> otype) &&
|
| 542 |
rschregle |
2.11 |
inset(ambset, objndx(mat))) {
|
| 543 |
greg |
2.1 |
/* Add photon port */
|
| 544 |
|
|
photonPorts = (SRCREC*)realloc(photonPorts,
|
| 545 |
|
|
(numPhotonPorts + 1) *
|
| 546 |
|
|
sizeof(SRCREC));
|
| 547 |
|
|
if (!photonPorts)
|
| 548 |
|
|
error(USER, "can't allocate photon ports");
|
| 549 |
|
|
|
| 550 |
|
|
photonPorts [numPhotonPorts].so = obj;
|
| 551 |
|
|
photonPorts [numPhotonPorts].sflags = 0;
|
| 552 |
|
|
|
| 553 |
|
|
if (!sfun [obj -> otype].of || !sfun[obj -> otype].of -> setsrc)
|
| 554 |
|
|
objerror(obj, USER, "illegal photon port");
|
| 555 |
|
|
|
| 556 |
|
|
setsource(photonPorts + numPhotonPorts, obj);
|
| 557 |
|
|
numPhotonPorts++;
|
| 558 |
|
|
}
|
| 559 |
|
|
}
|
| 560 |
rschregle |
2.11 |
|
| 561 |
|
|
if (!numPhotonPorts)
|
| 562 |
|
|
error(USER, "no valid photon ports found");
|
| 563 |
greg |
2.1 |
}
|
| 564 |
|
|
|
| 565 |
|
|
|
| 566 |
|
|
|
| 567 |
|
|
static void defaultEmissionFunc (EmissionMap* emap)
|
| 568 |
|
|
/* Default behaviour when no emission funcs defined for this source type */
|
| 569 |
|
|
{
|
| 570 |
|
|
objerror(emap -> src -> so, INTERNAL,
|
| 571 |
|
|
"undefined photon emission function");
|
| 572 |
|
|
}
|
| 573 |
|
|
|
| 574 |
|
|
|
| 575 |
|
|
|
| 576 |
|
|
void initPhotonEmissionFuncs ()
|
| 577 |
|
|
/* Init photonPartition[] and photonOrigin[] dispatch tables */
|
| 578 |
|
|
{
|
| 579 |
|
|
int i;
|
| 580 |
|
|
|
| 581 |
|
|
for (i = 0; i < NUMOTYPE; i++)
|
| 582 |
|
|
photonPartition [i] = photonOrigin [i] = defaultEmissionFunc;
|
| 583 |
|
|
|
| 584 |
|
|
photonPartition [OBJ_FACE] = photonPartition [OBJ_RING] = flatPhotonPartition;
|
| 585 |
|
|
photonPartition [OBJ_SOURCE] = sourcePhotonPartition;
|
| 586 |
|
|
photonPartition [OBJ_SPHERE] = spherePhotonPartition;
|
| 587 |
|
|
photonPartition [OBJ_CYLINDER] = cylPhotonPartition;
|
| 588 |
|
|
photonOrigin [OBJ_FACE] = photonOrigin [OBJ_RING] = flatPhotonOrigin;
|
| 589 |
|
|
photonOrigin [OBJ_SOURCE] = sourcePhotonOrigin;
|
| 590 |
|
|
photonOrigin [OBJ_SPHERE] = spherePhotonOrigin;
|
| 591 |
|
|
photonOrigin [OBJ_CYLINDER] = cylPhotonOrigin;
|
| 592 |
|
|
}
|
| 593 |
|
|
|
| 594 |
|
|
|
| 595 |
|
|
|
| 596 |
|
|
void initPhotonEmission (EmissionMap *emap, float numPdfSamples)
|
| 597 |
|
|
/* Initialize photon emission from partitioned light source emap -> src;
|
| 598 |
|
|
* this involves integrating the flux emitted from the current photon
|
| 599 |
|
|
* origin emap -> photonOrg and setting up a PDF to sample the emission
|
| 600 |
|
|
* distribution with numPdfSamples samples */
|
| 601 |
|
|
{
|
| 602 |
|
|
unsigned i, t, p;
|
| 603 |
|
|
double phi, cosTheta, sinTheta, du, dv, dOmega, thetaScale;
|
| 604 |
|
|
EmissionSample* sample;
|
| 605 |
greg |
2.4 |
const OBJREC* mod = findmaterial(emap -> src -> so);
|
| 606 |
greg |
2.1 |
static RAY r;
|
| 607 |
|
|
#if 0
|
| 608 |
|
|
static double lastCosNorm = FHUGE;
|
| 609 |
|
|
static SRCREC *lastSrc = NULL, *lastPort = NULL;
|
| 610 |
|
|
#endif
|
| 611 |
|
|
|
| 612 |
greg |
2.4 |
setcolor(emap -> partFlux, 0, 0, 0);
|
| 613 |
|
|
|
| 614 |
greg |
2.1 |
photonOrigin [emap -> src -> so -> otype] (emap);
|
| 615 |
|
|
cosTheta = DOT(emap -> ws, emap -> wh);
|
| 616 |
|
|
|
| 617 |
|
|
#if 0
|
| 618 |
|
|
if (emap -> src == lastSrc && emap -> port == lastPort &&
|
| 619 |
|
|
(emap -> src -> sflags & SDISTANT || mod -> omod == OVOID) &&
|
| 620 |
|
|
cosTheta == lastCosNorm)
|
| 621 |
|
|
/* Same source, port, and aperture-normal angle, and source is
|
| 622 |
|
|
either distant (and thus translationally invariant) or has
|
| 623 |
|
|
no modifier --> flux unchanged */
|
| 624 |
|
|
/* BUG: this optimisation ignores partial occlusion of ports and
|
| 625 |
|
|
can lead to erroneous "zero emission" bailouts.
|
| 626 |
|
|
It can also lead to bias with modifiers exhibiting high variance!
|
| 627 |
|
|
Disabled for now -- RS 12/13 */
|
| 628 |
|
|
return;
|
| 629 |
|
|
|
| 630 |
|
|
lastSrc = emap -> src;
|
| 631 |
|
|
lastPort = emap -> port;
|
| 632 |
|
|
lastCosNorm = cosTheta;
|
| 633 |
|
|
#endif
|
| 634 |
|
|
|
| 635 |
|
|
/* Need to recompute flux & PDF */
|
| 636 |
|
|
emap -> cdf = 0;
|
| 637 |
|
|
emap -> numSamples = 0;
|
| 638 |
|
|
|
| 639 |
|
|
if (cosTheta <= 0 &&
|
| 640 |
|
|
sqrt(1 - sqr(cosTheta)) <= emap -> cosThetaMax + FTINY)
|
| 641 |
|
|
/* Aperture below surface; no emission from current origin */
|
| 642 |
|
|
return;
|
| 643 |
|
|
|
| 644 |
|
|
if (mod -> omod == OVOID && !emap -> port &&
|
| 645 |
|
|
(cosTheta >= 1 - FTINY || (emap -> src -> sflags & SDISTANT &&
|
| 646 |
|
|
acos(cosTheta) + acos(emap -> cosThetaMax) <= 0.5 * PI))) {
|
| 647 |
|
|
/* Source is unmodified and has no port (which requires testing for
|
| 648 |
|
|
occlusion), and is either local with normal aligned aperture or
|
| 649 |
|
|
distant with aperture above surface; analytical flux & PDF */
|
| 650 |
|
|
setcolor(emap -> partFlux, mod -> oargs.farg [0],
|
| 651 |
|
|
mod -> oargs.farg [1], mod -> oargs.farg [2]);
|
| 652 |
|
|
|
| 653 |
|
|
/* Multiply radiance by Omega * dA to get flux */
|
| 654 |
|
|
scalecolor(emap -> partFlux,
|
| 655 |
|
|
PI * cosTheta * (1 - sqr(max(emap -> cosThetaMax, 0))) *
|
| 656 |
|
|
emap -> partArea);
|
| 657 |
|
|
}
|
| 658 |
|
|
|
| 659 |
|
|
else {
|
| 660 |
|
|
/* Source is either modified, has a port, is local with off-normal
|
| 661 |
|
|
aperture, or distant with aperture partly below surface; get flux
|
| 662 |
|
|
via numerical integration */
|
| 663 |
|
|
thetaScale = (1 - emap -> cosThetaMax);
|
| 664 |
|
|
|
| 665 |
|
|
/* Figga out numba of aperture samples for integration;
|
| 666 |
|
|
numTheta / numPhi ratio is 1 / PI */
|
| 667 |
|
|
du = sqrt(pdfSamples * 2 * thetaScale);
|
| 668 |
|
|
emap -> numTheta = max(du + 0.5, 1);
|
| 669 |
|
|
emap -> numPhi = max(PI * du + 0.5, 1);
|
| 670 |
|
|
|
| 671 |
|
|
dOmega = 2 * PI * thetaScale / (emap -> numTheta * emap -> numPhi);
|
| 672 |
|
|
thetaScale /= emap -> numTheta;
|
| 673 |
|
|
|
| 674 |
|
|
/* Allocate PDF, baby */
|
| 675 |
|
|
sample = emap -> samples = (EmissionSample*)
|
| 676 |
|
|
realloc(emap -> samples,
|
| 677 |
|
|
sizeof(EmissionSample) *
|
| 678 |
|
|
emap -> numTheta * emap -> numPhi);
|
| 679 |
|
|
if (!emap -> samples)
|
| 680 |
|
|
error(USER, "can't allocate emission PDF");
|
| 681 |
|
|
|
| 682 |
|
|
VCOPY(r.rorg, emap -> photonOrg);
|
| 683 |
|
|
VCOPY(r.rop, emap -> photonOrg);
|
| 684 |
greg |
2.5 |
r.rmax = 0;
|
| 685 |
greg |
2.1 |
|
| 686 |
|
|
for (t = 0; t < emap -> numTheta; t++) {
|
| 687 |
|
|
for (p = 0; p < emap -> numPhi; p++) {
|
| 688 |
|
|
/* This uniform mapping handles 0 <= thetaMax <= PI */
|
| 689 |
|
|
cosTheta = 1 - (t + pmapRandom(emitState)) * thetaScale;
|
| 690 |
|
|
sinTheta = sqrt(1 - sqr(cosTheta));
|
| 691 |
|
|
phi = 2 * PI * (p + pmapRandom(emitState)) / emap -> numPhi;
|
| 692 |
|
|
du = cos(phi) * sinTheta;
|
| 693 |
|
|
dv = sin(phi) * sinTheta;
|
| 694 |
|
|
rayorigin(&r, PRIMARY, NULL, NULL);
|
| 695 |
|
|
|
| 696 |
|
|
for (i = 0; i < 3; i++)
|
| 697 |
|
|
r.rdir [i] = du * emap -> uh [i] + dv * emap -> vh [i] +
|
| 698 |
|
|
cosTheta * emap -> wh [i];
|
| 699 |
|
|
|
| 700 |
|
|
/* Sample behind surface? */
|
| 701 |
|
|
VCOPY(r.ron, emap -> ws);
|
| 702 |
|
|
if ((r.rod = DOT(r.rdir, r.ron)) <= 0)
|
| 703 |
|
|
continue;
|
| 704 |
|
|
|
| 705 |
|
|
/* Get radiance emitted in this direction; to get flux we
|
| 706 |
|
|
multiply by cos(theta_surface), dOmega, and dA. Ray
|
| 707 |
|
|
is directed towards light source for raytexture(). */
|
| 708 |
|
|
if (!(emap -> src -> sflags & SDISTANT))
|
| 709 |
|
|
for (i = 0; i < 3; i++)
|
| 710 |
|
|
r.rdir [i] = -r.rdir [i];
|
| 711 |
|
|
|
| 712 |
|
|
/* Port occluded in this direction? */
|
| 713 |
|
|
if (emap -> port && localhit(&r, &thescene))
|
| 714 |
|
|
continue;
|
| 715 |
|
|
|
| 716 |
|
|
raytexture(&r, mod -> omod);
|
| 717 |
|
|
setcolor(r.rcol, mod -> oargs.farg [0], mod -> oargs.farg [1],
|
| 718 |
|
|
mod -> oargs.farg [2]);
|
| 719 |
|
|
multcolor(r.rcol, r.pcol);
|
| 720 |
|
|
|
| 721 |
|
|
/* Multiply by cos(theta_surface) */
|
| 722 |
|
|
scalecolor(r.rcol, r.rod);
|
| 723 |
|
|
|
| 724 |
|
|
/* Add PDF sample if nonzero; importance info for photon emission
|
| 725 |
|
|
* could go here... */
|
| 726 |
|
|
if (colorAvg(r.rcol)) {
|
| 727 |
|
|
copycolor(sample -> pdf, r.rcol);
|
| 728 |
|
|
sample -> cdf = emap -> cdf += colorAvg(sample -> pdf);
|
| 729 |
|
|
sample -> theta = t;
|
| 730 |
|
|
sample++ -> phi = p;
|
| 731 |
|
|
emap -> numSamples++;
|
| 732 |
|
|
addcolor(emap -> partFlux, r.rcol);
|
| 733 |
|
|
}
|
| 734 |
|
|
}
|
| 735 |
|
|
}
|
| 736 |
|
|
|
| 737 |
|
|
/* Multiply by dOmega * dA */
|
| 738 |
|
|
scalecolor(emap -> partFlux, dOmega * emap -> partArea);
|
| 739 |
|
|
}
|
| 740 |
|
|
}
|
| 741 |
|
|
|
| 742 |
|
|
|
| 743 |
|
|
|
| 744 |
|
|
#define vomitPhoton emitPhoton
|
| 745 |
|
|
#define bluarrrghPhoton vomitPhoton
|
| 746 |
|
|
|
| 747 |
|
|
void emitPhoton (const EmissionMap* emap, RAY* ray)
|
| 748 |
|
|
/* Emit photon from current partition emap -> partitionCnt based on
|
| 749 |
|
|
emission distribution. Returns new photon ray. */
|
| 750 |
|
|
{
|
| 751 |
|
|
unsigned long i, lo, hi;
|
| 752 |
|
|
const EmissionSample* sample = emap -> samples;
|
| 753 |
|
|
RREAL du, dv, cosTheta, cosThetaSqr, sinTheta, phi;
|
| 754 |
greg |
2.4 |
const OBJREC* mod = findmaterial(emap -> src -> so);
|
| 755 |
greg |
2.1 |
|
| 756 |
|
|
/* Choose a new origin within current partition for every
|
| 757 |
|
|
emitted photon to break up clustering artifacts */
|
| 758 |
|
|
photonOrigin [emap -> src -> so -> otype] ((EmissionMap*)emap);
|
| 759 |
greg |
2.5 |
/* If we have a local glow source with a maximum radius, then
|
| 760 |
|
|
restrict our photon to the specified distance (otherwise no limit) */
|
| 761 |
greg |
2.6 |
if (mod -> otype == MAT_GLOW && !(emap -> src -> sflags & SDISTANT)
|
| 762 |
greg |
2.5 |
&& mod -> oargs.farg[3] > FTINY)
|
| 763 |
|
|
ray -> rmax = mod -> oargs.farg[3];
|
| 764 |
|
|
else
|
| 765 |
|
|
ray -> rmax = 0;
|
| 766 |
greg |
2.1 |
rayorigin(ray, PRIMARY, NULL, NULL);
|
| 767 |
|
|
|
| 768 |
|
|
if (!emap -> numSamples) {
|
| 769 |
|
|
/* Source is unmodified and has no port, and either local with
|
| 770 |
|
|
normal aligned aperture, or distant with aperture above surface;
|
| 771 |
|
|
use cosine weighted distribution */
|
| 772 |
|
|
cosThetaSqr = 1 - pmapRandom(emitState) *
|
| 773 |
|
|
(1 - sqr(max(emap -> cosThetaMax, 0)));
|
| 774 |
|
|
cosTheta = sqrt(cosThetaSqr);
|
| 775 |
|
|
sinTheta = sqrt(1 - cosThetaSqr);
|
| 776 |
|
|
phi = 2 * PI * pmapRandom(emitState);
|
| 777 |
|
|
setcolor(ray -> rcol, mod -> oargs.farg [0], mod -> oargs.farg [1],
|
| 778 |
|
|
mod -> oargs.farg [2]);
|
| 779 |
|
|
}
|
| 780 |
|
|
|
| 781 |
|
|
else {
|
| 782 |
|
|
/* Source is either modified, has a port, is local with off-normal
|
| 783 |
|
|
aperture, or distant with aperture partly below surface; choose
|
| 784 |
|
|
direction from constructed cumulative distribution function with
|
| 785 |
|
|
Monte Carlo inversion using binary search. */
|
| 786 |
|
|
du = pmapRandom(emitState) * emap -> cdf;
|
| 787 |
|
|
lo = 1;
|
| 788 |
|
|
hi = emap -> numSamples;
|
| 789 |
|
|
|
| 790 |
|
|
while (hi > lo) {
|
| 791 |
|
|
i = (lo + hi) >> 1;
|
| 792 |
|
|
sample = emap -> samples + i - 1;
|
| 793 |
|
|
|
| 794 |
|
|
if (sample -> cdf >= du)
|
| 795 |
|
|
hi = i;
|
| 796 |
|
|
if (sample -> cdf < du)
|
| 797 |
|
|
lo = i + 1;
|
| 798 |
|
|
}
|
| 799 |
|
|
|
| 800 |
|
|
/* This is a uniform mapping, mon */
|
| 801 |
|
|
cosTheta = 1 - (sample -> theta + pmapRandom(emitState)) *
|
| 802 |
|
|
(1 - emap -> cosThetaMax) / emap -> numTheta;
|
| 803 |
|
|
sinTheta = sqrt(1 - sqr(cosTheta));
|
| 804 |
|
|
phi = 2 * PI * (sample -> phi + pmapRandom(emitState)) / emap -> numPhi;
|
| 805 |
|
|
copycolor(ray -> rcol, sample -> pdf);
|
| 806 |
|
|
}
|
| 807 |
|
|
|
| 808 |
|
|
/* Normalize photon flux so that average over RGB is 1 */
|
| 809 |
|
|
colorNorm(ray -> rcol);
|
| 810 |
|
|
|
| 811 |
|
|
VCOPY(ray -> rorg, emap -> photonOrg);
|
| 812 |
|
|
du = cos(phi) * sinTheta;
|
| 813 |
|
|
dv = sin(phi) * sinTheta;
|
| 814 |
|
|
|
| 815 |
|
|
for (i = 0; i < 3; i++)
|
| 816 |
|
|
ray -> rdir [i] = du * emap -> uh [i] + dv * emap -> vh [i] +
|
| 817 |
|
|
cosTheta * emap -> wh [i];
|
| 818 |
|
|
|
| 819 |
|
|
if (emap -> src -> sflags & SDISTANT)
|
| 820 |
|
|
/* Distant source; reverse ray direction to point into the scene. */
|
| 821 |
|
|
for (i = 0; i < 3; i++)
|
| 822 |
|
|
ray -> rdir [i] = -ray -> rdir [i];
|
| 823 |
|
|
|
| 824 |
|
|
if (emap -> port)
|
| 825 |
|
|
/* Photon emitted from port; move origin just behind port so it
|
| 826 |
|
|
will be scattered */
|
| 827 |
|
|
for (i = 0; i < 3; i++)
|
| 828 |
|
|
ray -> rorg [i] -= 2 * FTINY * ray -> rdir [i];
|
| 829 |
|
|
|
| 830 |
|
|
/* Assign emitting light source index */
|
| 831 |
|
|
ray -> rsrc = emap -> src - source;
|
| 832 |
|
|
}
|
| 833 |
|
|
|
| 834 |
|
|
|
| 835 |
|
|
|
| 836 |
|
|
void multDirectPmap (RAY *r)
|
| 837 |
|
|
/* Factor irradiance from direct photons into r -> rcol; interface to
|
| 838 |
|
|
* direct() */
|
| 839 |
|
|
{
|
| 840 |
|
|
COLOR photonIrrad;
|
| 841 |
|
|
|
| 842 |
|
|
/* Lookup direct photon irradiance */
|
| 843 |
|
|
(directPmap -> lookup)(directPmap, r, photonIrrad);
|
| 844 |
|
|
|
| 845 |
|
|
/* Multiply with coefficient in ray */
|
| 846 |
|
|
multcolor(r -> rcol, photonIrrad);
|
| 847 |
|
|
|
| 848 |
|
|
return;
|
| 849 |
|
|
}
|
| 850 |
|
|
|
| 851 |
|
|
|
| 852 |
|
|
|
| 853 |
|
|
void inscatterVolumePmap (RAY *r, COLOR inscatter)
|
| 854 |
|
|
/* Add inscattering from volume photon map; interface to srcscatter() */
|
| 855 |
|
|
{
|
| 856 |
|
|
/* Add ambient in-scattering via lookup callback */
|
| 857 |
|
|
(volumePmap -> lookup)(volumePmap, r, inscatter);
|
| 858 |
|
|
}
|
