| 1 | greg | 2.1 | #ifndef lint | 
| 2 | greg | 2.2 | static const char RCSid[] = "$Id: pmcontrib2.c,v 2.1 2016/09/29 21:51:58 greg Exp $"; | 
| 3 | greg | 2.1 | #endif | 
| 4 |  |  |  | 
| 5 |  |  | /* | 
| 6 |  |  | ====================================================================== | 
| 7 |  |  | Photon map support for using light source contributions | 
| 8 |  |  |  | 
| 9 |  |  | Roland Schregle (roland.schregle@{hslu.ch, gmail.com}) | 
| 10 |  |  | (c) Lucerne University of Applied Sciences and Arts, | 
| 11 |  |  | supported by the Swiss National Science Foundation (SNSF, #147053) | 
| 12 |  |  | ====================================================================== | 
| 13 |  |  |  | 
| 14 | greg | 2.2 | $Id: pmcontrib2.c,v 2.1 2016/09/29 21:51:58 greg Exp $ | 
| 15 | greg | 2.1 | */ | 
| 16 |  |  |  | 
| 17 |  |  |  | 
| 18 |  |  | #include "pmapcontrib.h" | 
| 19 |  |  | #include "pmapmat.h" | 
| 20 |  |  | #include "pmapsrc.h" | 
| 21 |  |  | #include "pmaprand.h" | 
| 22 |  |  | #include "pmapio.h" | 
| 23 |  |  | #include "pmapdiag.h" | 
| 24 |  |  | #include "rcontrib.h" | 
| 25 |  |  | #include "otypes.h" | 
| 26 |  |  |  | 
| 27 |  |  |  | 
| 28 |  |  |  | 
| 29 |  |  | static void setPmapContribParams (PhotonMap *pmap, LUTAB *srcContrib) | 
| 30 |  |  | /* Set parameters for light source contributions */ | 
| 31 |  |  | { | 
| 32 |  |  | /* Set light source modifier list and appropriate callback to extract | 
| 33 |  |  | * their contributions from the photon map */ | 
| 34 |  |  | if (pmap) { | 
| 35 |  |  | pmap -> srcContrib = srcContrib; | 
| 36 |  |  | pmap -> lookup = photonContrib; | 
| 37 |  |  | /* Ensure we get all requested photon contribs during lookups */ | 
| 38 |  |  | pmap -> gatherTolerance = 1.0; | 
| 39 |  |  | } | 
| 40 |  |  | } | 
| 41 |  |  |  | 
| 42 |  |  |  | 
| 43 |  |  |  | 
| 44 |  |  | static void checkPmapContribs (const PhotonMap *pmap, LUTAB *srcContrib) | 
| 45 |  |  | /* Check modifiers for light source contributions */ | 
| 46 |  |  | { | 
| 47 |  |  | const PhotonPrimary  *primary = pmap -> primaries; | 
| 48 |  |  | PhotonPrimaryIdx     i, found = 0; | 
| 49 |  |  | OBJREC *srcMod; | 
| 50 |  |  |  | 
| 51 |  |  | /* Make sure at least one of the modifiers is actually in the pmap, | 
| 52 |  |  | * otherwise findPhotons() winds up in an infinite loop! */ | 
| 53 |  |  | for (i = pmap -> numPrimary; i; --i, ++primary) { | 
| 54 |  |  | if (primary -> srcIdx < 0 || primary -> srcIdx >= nsources) | 
| 55 |  |  | error(INTERNAL, "invalid light source index in photon map"); | 
| 56 |  |  |  | 
| 57 |  |  | srcMod = findmaterial(source [primary -> srcIdx].so); | 
| 58 |  |  | if ((MODCONT*)lu_find(srcContrib, srcMod -> oname) -> data) | 
| 59 |  |  | ++found; | 
| 60 |  |  | } | 
| 61 |  |  |  | 
| 62 |  |  | if (!found) | 
| 63 |  |  | error(USER, "modifiers not in photon map"); | 
| 64 |  |  | } | 
| 65 |  |  |  | 
| 66 |  |  |  | 
| 67 |  |  |  | 
| 68 |  |  | void initPmapContrib (LUTAB *srcContrib, unsigned numSrcContrib) | 
| 69 |  |  | { | 
| 70 |  |  | unsigned t; | 
| 71 |  |  |  | 
| 72 |  |  | for (t = 0; t < NUM_PMAP_TYPES; t++) | 
| 73 |  |  | if (photonMaps [t] && t != PMAP_TYPE_CONTRIB) { | 
| 74 |  |  | sprintf(errmsg, "%s photon map does not support contributions", | 
| 75 |  |  | pmapName [t]); | 
| 76 |  |  | error(USER, errmsg); | 
| 77 |  |  | } | 
| 78 |  |  |  | 
| 79 |  |  | /* Get params */ | 
| 80 |  |  | setPmapContribParams(contribPmap, srcContrib); | 
| 81 |  |  |  | 
| 82 |  |  | if (contribPhotonMapping) { | 
| 83 |  |  | if (contribPmap -> maxGather < numSrcContrib) { | 
| 84 |  |  | /* Adjust density estimate bandwidth if lower than modifier | 
| 85 |  |  | * count, otherwise contributions are missing */ | 
| 86 |  |  | error(WARNING, "contrib density estimate bandwidth too low, " | 
| 87 |  |  | "adjusting to modifier count"); | 
| 88 |  |  | contribPmap -> maxGather = numSrcContrib; | 
| 89 |  |  | } | 
| 90 |  |  |  | 
| 91 |  |  | /* Sanity check */ | 
| 92 |  |  | checkPmapContribs(contribPmap, srcContrib); | 
| 93 |  |  | } | 
| 94 |  |  | } | 
| 95 |  |  |  | 
| 96 |  |  |  | 
| 97 |  |  |  | 
| 98 |  |  | void photonContrib (PhotonMap *pmap, RAY *ray, COLOR irrad) | 
| 99 |  |  | /* Sum up light source contributions from photons in pmap->srcContrib */ | 
| 100 |  |  | { | 
| 101 |  |  | unsigned                i; | 
| 102 |  |  | PhotonSearchQueueNode   *sqn; | 
| 103 |  |  | float                   r, invArea; | 
| 104 |  |  | RREAL                   rayCoeff [3]; | 
| 105 |  |  | Photon                  *photon; | 
| 106 |  |  | static char             warn = 1; | 
| 107 |  |  |  | 
| 108 |  |  | setcolor(irrad, 0, 0, 0); | 
| 109 |  |  |  | 
| 110 |  |  | if (!pmap -> maxGather) | 
| 111 |  |  | return; | 
| 112 |  |  |  | 
| 113 |  |  | /* Ignore sources */ | 
| 114 |  |  | if (ray -> ro && islight(objptr(ray -> ro -> omod) -> otype)) | 
| 115 |  |  | return; | 
| 116 |  |  |  | 
| 117 |  |  | /* Get cumulative path coefficient up to photon lookup point */ | 
| 118 |  |  | raycontrib(rayCoeff, ray, PRIMARY); | 
| 119 |  |  |  | 
| 120 |  |  | /* Lookup photons */ | 
| 121 |  |  | pmap -> squeue.tail = 0; | 
| 122 |  |  | findPhotons(pmap, ray); | 
| 123 |  |  |  | 
| 124 |  |  | /* Need at least 2 photons */ | 
| 125 |  |  | if (pmap -> squeue.tail < 2) { | 
| 126 |  |  | #ifdef PMAP_NONEFOUND | 
| 127 |  |  | sprintf(errmsg, "no photons found on %s at (%.3f, %.3f, %.3f)", | 
| 128 |  |  | ray -> ro ? ray -> ro -> oname : "<null>", | 
| 129 |  |  | ray -> rop [0], ray -> rop [1], ray -> rop [2]); | 
| 130 |  |  | error(WARNING, errmsg); | 
| 131 |  |  | #endif | 
| 132 |  |  |  | 
| 133 |  |  | return; | 
| 134 |  |  | } | 
| 135 |  |  |  | 
| 136 |  |  | /* Average (squared) radius between furthest two photons to improve | 
| 137 |  |  | * accuracy and get inverse search area 1 / (PI * r^2), with extra | 
| 138 |  |  | * normalisation factor 1 / PI for ambient calculation */ | 
| 139 |  |  | sqn = pmap -> squeue.node + 1; | 
| 140 |  |  | r = max(sqn -> dist2, (sqn + 1) -> dist2); | 
| 141 |  |  | r = 0.25 * (pmap -> maxDist2 + r + 2 * sqrt(pmap -> maxDist2 * r)); | 
| 142 |  |  | invArea = 1 / (PI * PI * r); | 
| 143 |  |  |  | 
| 144 |  |  | /* Skip the extra photon */ | 
| 145 |  |  | for (i = 1 ; i < pmap -> squeue.tail; i++, sqn++) { | 
| 146 |  |  | COLOR flux; | 
| 147 |  |  |  | 
| 148 |  |  | /* Get photon's contribution to density estimate */ | 
| 149 |  |  | photon = getNearestPhoton(&pmap -> squeue, sqn -> idx); | 
| 150 |  |  | getPhotonFlux(photon, flux); | 
| 151 |  |  | scalecolor(flux, invArea); | 
| 152 |  |  | #ifdef PMAP_EPANECHNIKOV | 
| 153 |  |  | /* Apply Epanechnikov kernel to photon flux based on photon distance */ | 
| 154 |  |  | scalecolor(flux, 2 * (1 - sqn -> dist2 / r)); | 
| 155 |  |  | #endif | 
| 156 |  |  | addcolor(irrad, flux); | 
| 157 |  |  |  | 
| 158 |  |  | if (pmap -> srcContrib) { | 
| 159 |  |  | const PhotonPrimary  *primary = pmap -> primaries + | 
| 160 |  |  | photon -> primary; | 
| 161 |  |  | const SRCREC         *sp = &source [primary -> srcIdx]; | 
| 162 |  |  | OBJREC               *srcMod = findmaterial(sp -> so); | 
| 163 |  |  | MODCONT *srcContrib = (MODCONT*)lu_find(pmap -> srcContrib, | 
| 164 |  |  | srcMod -> oname) -> data; | 
| 165 |  |  | double   srcBinReal; | 
| 166 |  |  | int      srcBin; | 
| 167 |  |  | RAY      srcRay; | 
| 168 |  |  |  | 
| 169 |  |  | if (!srcContrib) | 
| 170 |  |  | continue; | 
| 171 |  |  |  | 
| 172 |  |  | /* Photon's emitting light source has modifier whose contributions | 
| 173 |  |  | * are sought */ | 
| 174 |  |  | if (srcContrib -> binv -> type != NUM) { | 
| 175 |  |  | /* Use intersection function to set shadow ray parameters if | 
| 176 |  |  | * it's not simply a constant */ | 
| 177 |  |  | rayorigin(&srcRay, SHADOW, NULL, NULL); | 
| 178 |  |  | srcRay.rsrc = primary -> srcIdx; | 
| 179 |  |  | #ifdef PMAP_PRIMARYPOS | 
| 180 |  |  | VCOPY(srcRay.rorg, primary -> pos); | 
| 181 |  |  | #else | 
| 182 |  |  | /* No primary hitpoints; set dummy ray origin and warn once */ | 
| 183 |  |  | srcRay.rorg [0] = srcRay.rorg [1] = srcRay.rorg [2] = 0; | 
| 184 |  |  | if (warn) { | 
| 185 |  |  | error(WARNING, "no photon primary hitpoints for bin evaluation;" | 
| 186 |  |  | " using dummy (0,0,0) !"); | 
| 187 |  |  | warn = 0; | 
| 188 |  |  | } | 
| 189 |  |  | #endif | 
| 190 |  |  | decodedir(srcRay.rdir, primary -> dir); | 
| 191 |  |  |  | 
| 192 |  |  | if (!(sp->sflags & SDISTANT | 
| 193 |  |  | ? sourcehit(&srcRay) | 
| 194 |  |  | : (*ofun[sp -> so -> otype].funp)(sp -> so, &srcRay))) | 
| 195 |  |  | continue;                /* XXX shouldn't happen! */ | 
| 196 |  |  |  | 
| 197 |  |  | worldfunc(RCCONTEXT, &srcRay); | 
| 198 |  |  | set_eparams((char *)srcContrib -> params); | 
| 199 |  |  | } | 
| 200 |  |  |  | 
| 201 |  |  | if ((srcBinReal = evalue(srcContrib -> binv)) < -.5) | 
| 202 |  |  | continue;           /* silently ignore negative bins */ | 
| 203 |  |  |  | 
| 204 |  |  | if ((srcBin = srcBinReal + .5) >= srcContrib -> nbins) { | 
| 205 |  |  | error(WARNING, "bad bin number (ignored)"); | 
| 206 |  |  | continue; | 
| 207 |  |  | } | 
| 208 |  |  |  | 
| 209 |  |  | if (!contrib) { | 
| 210 |  |  | /* Ray coefficient mode; normalise by light source radiance | 
| 211 |  |  | * after applying distrib pattern */ | 
| 212 |  |  | int j; | 
| 213 |  |  |  | 
| 214 |  |  | raytexture(ray, srcMod -> omod); | 
| 215 |  |  | setcolor(ray -> rcol, srcMod -> oargs.farg [0], | 
| 216 |  |  | srcMod -> oargs.farg [1], srcMod -> oargs.farg [2]); | 
| 217 |  |  | multcolor(ray -> rcol, ray -> pcol); | 
| 218 |  |  | for (j = 0; j < 3; j++) | 
| 219 |  |  | flux [j] = ray -> rcol [j] ? flux [j] / ray -> rcol [j] : 0; | 
| 220 |  |  | } | 
| 221 |  |  |  | 
| 222 |  |  | multcolor(flux, rayCoeff); | 
| 223 |  |  | addcolor(srcContrib -> cbin [srcBin], flux); | 
| 224 |  |  | } | 
| 225 |  |  | } | 
| 226 |  |  |  | 
| 227 |  |  | return; | 
| 228 |  |  | } |