| 1 |
/* |
| 2 |
================================================================== |
| 3 |
Photon map data structures and kd-tree handling |
| 4 |
|
| 5 |
Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) |
| 6 |
(c) Fraunhofer Institute for Solar Energy Systems, |
| 7 |
Lucerne University of Applied Sciences & Arts |
| 8 |
================================================================== |
| 9 |
|
| 10 |
$Id: pmapdata.h,v 4.20 2015/01/30 19:08:50 taschreg Exp taschreg $ |
| 11 |
*/ |
| 12 |
|
| 13 |
|
| 14 |
#ifndef PMAPDATA_H |
| 15 |
#define PMAPDATA_H |
| 16 |
|
| 17 |
#include "ray.h" |
| 18 |
#include "pmaptype.h" |
| 19 |
#include "lookup.h" |
| 20 |
|
| 21 |
|
| 22 |
/* Define PMAP_FLOAT_FLUX to store photon flux as floats instead of |
| 23 |
* compact RGBE, which was found to improve accuracy in analytical |
| 24 |
* validation. */ |
| 25 |
#ifdef PMAP_FLOAT_FLUX |
| 26 |
#define setPhotonFlux(p,f) copycolor((p) -> flux, f) |
| 27 |
#define getPhotonFlux(p,f) copycolor(f, (p) -> flux) |
| 28 |
#else |
| 29 |
#define setPhotonFlux(p,f) setcolr((p)->flux, (f)[0], (f)[1], (f)[2]) |
| 30 |
#define getPhotonFlux(p,f) colr_color(f, (p) -> flux) |
| 31 |
#endif |
| 32 |
|
| 33 |
|
| 34 |
/* Primary photon ray for light source contributions */ |
| 35 |
typedef struct { |
| 36 |
short srcIdx; /* Index of emitting light source */ |
| 37 |
float dir [3], org [3]; /* Incident dir & origin on source */ |
| 38 |
} PhotonPrimary; |
| 39 |
|
| 40 |
#define photonSrcIdx(pm, p) ((pm) -> primary [(p) -> primary].srcIdx) |
| 41 |
|
| 42 |
|
| 43 |
typedef struct { |
| 44 |
float pos [3]; /* Photon position */ |
| 45 |
signed char norm [3]; /* Surface normal at pos (incident |
| 46 |
direction for volume photons) */ |
| 47 |
char flags; /* Bit 0-1: kd-tree discriminator axis, |
| 48 |
Bit 2: caustic photon */ |
| 49 |
#ifdef PMAP_FLOAT_FLUX |
| 50 |
COLOR flux; |
| 51 |
#else |
| 52 |
COLR flux; /* Photon flux */ |
| 53 |
#endif |
| 54 |
|
| 55 |
unsigned primary; /* Index to primary ray */ |
| 56 |
} Photon; |
| 57 |
|
| 58 |
/* Photon flag bitmasks and manipulation macros */ |
| 59 |
#define PMAP_DISCR_BIT 3 |
| 60 |
#define PMAP_CAUST_BIT 4 |
| 61 |
#define photonDiscr(p) ((p).flags & PMAP_DISCR_BIT) |
| 62 |
#define setPhotonDiscr(p, d) ((p).flags = ((p).flags & ~PMAP_DISCR_BIT) | \ |
| 63 |
((d) & PMAP_DISCR_BIT)) |
| 64 |
|
| 65 |
/* Photon map type tests */ |
| 66 |
#define isGlobalPmap(p) ((p) -> type == PMAP_TYPE_GLOBAL) |
| 67 |
#define isCausticPmap(p) ((p) -> type == PMAP_TYPE_CAUSTIC) |
| 68 |
#define isContribPmap(p) ((p) -> type == PMAP_TYPE_CONTRIB) |
| 69 |
#define isVolumePmap(p) ((p) -> type == PMAP_TYPE_VOLUME) |
| 70 |
|
| 71 |
|
| 72 |
/* Queue node for photon lookups */ |
| 73 |
typedef struct { |
| 74 |
Photon *photon; |
| 75 |
float dist; |
| 76 |
} PhotonSQNode; |
| 77 |
|
| 78 |
/* Bias compensation history node */ |
| 79 |
typedef struct { |
| 80 |
COLOR irrad; |
| 81 |
float weight; |
| 82 |
} PhotonBCNode; |
| 83 |
|
| 84 |
|
| 85 |
struct PhotonMap; /* Forward declarations */ |
| 86 |
|
| 87 |
typedef struct PhotonMap { |
| 88 |
PhotonMapType type; /* See pmaptype.h */ |
| 89 |
char *fileName; /* Photon map file */ |
| 90 |
Photon *heap; /* Photon k-d tree as linear array */ |
| 91 |
PhotonSQNode *squeue; /* Search queue */ |
| 92 |
PhotonBCNode *biasCompHist; /* Bias compensation history */ |
| 93 |
char lookupFlags; /* Flags passed to findPhotons() */ |
| 94 |
|
| 95 |
unsigned long distribTarget, /* Num stored specified by user */ |
| 96 |
heapSize, |
| 97 |
heapSizeInc, |
| 98 |
heapEnd, /* Num actually stored in heap */ |
| 99 |
numDensity, /* Num density estimates */ |
| 100 |
totalGathered, /* Total photons gathered */ |
| 101 |
numLookups, /* Counters for short photon lookups */ |
| 102 |
numShortLookups; |
| 103 |
|
| 104 |
unsigned minGather, /* Specified min/max photons per */ |
| 105 |
maxGather, /* density estimate */ |
| 106 |
squeueSize, |
| 107 |
squeueEnd, |
| 108 |
minGathered, /* Min/max photons actually gathered */ |
| 109 |
maxGathered, /* per density estimate */ |
| 110 |
shortLookupPct; /* Percentage of short lookups (for |
| 111 |
statistics output */ |
| 112 |
|
| 113 |
/* NOTE: All distances are SQUARED */ |
| 114 |
float maxDist, /* Max search radius during NN search */ |
| 115 |
maxDist0, /* Initial value for above */ |
| 116 |
maxDistLimit, /* Hard limit for above */ |
| 117 |
CoGdist, /* Avg distance to centre of gravity */ |
| 118 |
maxPos [3], minPos [3], /* Max & min photon positions */ |
| 119 |
distribRatio, /* Probability of photon storage */ |
| 120 |
gatherTolerance, /* Fractional deviation from minGather/ |
| 121 |
maxGather for short lookup */ |
| 122 |
minError, maxError, /* Min/max/rms density estimate error */ |
| 123 |
rmsError; |
| 124 |
|
| 125 |
FVECT CoG; /* Centre of gravity (avg photon pos) */ |
| 126 |
COLOR photonFlux; /* Average photon flux */ |
| 127 |
unsigned short randState [3]; /* Local RNG state */ |
| 128 |
|
| 129 |
void (*lookup)(struct PhotonMap*, RAY*, COLOR); |
| 130 |
/* Callback for type-specific photon |
| 131 |
* lookup (usually density estimate) */ |
| 132 |
|
| 133 |
PhotonPrimary *primary; /* Primary photon rays & associated |
| 134 |
counters */ |
| 135 |
unsigned primarySize, primaryEnd; |
| 136 |
|
| 137 |
LUTAB *srcContrib; /* lookup table for source contribs */ |
| 138 |
} PhotonMap; |
| 139 |
|
| 140 |
|
| 141 |
|
| 142 |
/* Photon maps by type (see PhotonMapType) */ |
| 143 |
extern PhotonMap *photonMaps []; |
| 144 |
|
| 145 |
/* Macros for specific photon map types */ |
| 146 |
#define globalPmap (photonMaps [PMAP_TYPE_GLOBAL]) |
| 147 |
#define preCompPmap (photonMaps [PMAP_TYPE_PRECOMP]) |
| 148 |
#define causticPmap (photonMaps [PMAP_TYPE_CAUSTIC]) |
| 149 |
#define volumePmap (photonMaps [PMAP_TYPE_VOLUME]) |
| 150 |
#define directPmap (photonMaps [PMAP_TYPE_DIRECT]) |
| 151 |
#define contribPmap (photonMaps [PMAP_TYPE_CONTRIB]) |
| 152 |
|
| 153 |
|
| 154 |
|
| 155 |
void initPhotonMap (PhotonMap *pmap, PhotonMapType t); |
| 156 |
/* Initialise empty photon map of specified type */ |
| 157 |
|
| 158 |
const PhotonPrimary* addPhotonPrimary (PhotonMap *pmap, const RAY *ray); |
| 159 |
/* Add primary ray for emitted photon and save light source index, origin |
| 160 |
* on source, and emitted direction; used by contrib photons */ |
| 161 |
|
| 162 |
const Photon* addPhoton (PhotonMap *pmap, const RAY *ray); |
| 163 |
/* Create new photon with ray's direction, intersection point, and flux, |
| 164 |
and add to photon map subject to acceptance probability pmap -> |
| 165 |
distribRatio for global density control; if the photon is rejected, |
| 166 |
NULL is returned. The flux is scaled by ray -> rweight and |
| 167 |
1 / pmap -> distribRatio. */ |
| 168 |
|
| 169 |
void balancePhotons (PhotonMap *pmap, double *photonFlux); |
| 170 |
/* Build a balanced kd-tree as heap to guarantee logarithmic search |
| 171 |
* times. This must be called prior to performing photon search with |
| 172 |
* findPhotons(). |
| 173 |
* PhotonFlux is the flux scaling factor per photon averaged over RGB. In |
| 174 |
* the case of a contribution photon map, this is an array with a |
| 175 |
* separate factor specific to each light source due to non-uniform |
| 176 |
* photon emission; Otherwise it is referenced as a scalar value. Flux is |
| 177 |
* not scaled if photonFlux == NULL. */ |
| 178 |
|
| 179 |
void buildHeap (Photon *heap, unsigned long *heapIdx, |
| 180 |
unsigned long *heapXdi, const float min [3], |
| 181 |
const float max [3], unsigned long left, |
| 182 |
unsigned long right, unsigned long root); |
| 183 |
/* Recursive part of balancePhotons(..); builds heap from subarray |
| 184 |
* defined by indices left and right. */ |
| 185 |
|
| 186 |
void findPhotons (PhotonMap* pmap, const RAY *ray); |
| 187 |
/* Find pmap -> squeueSize closest photons to ray -> rop with similar |
| 188 |
normal. For volume photons ray -> rorg is used and the normal is |
| 189 |
ignored (being the incident direction in this case). Found photons |
| 190 |
are placed in pmap -> squeue, with pmap -> squeueEnd being the number |
| 191 |
actually found. */ |
| 192 |
|
| 193 |
Photon *find1Photon (PhotonMap *pmap, const RAY *ray); |
| 194 |
/* Finds single closest photon to ray -> rop with similar normal. |
| 195 |
Returns NULL if none found. */ |
| 196 |
|
| 197 |
void deletePhotons (PhotonMap*); |
| 198 |
/* Free dem mammaries... */ |
| 199 |
|
| 200 |
#endif |
