--- ray/src/rt/m_bsdf.c 2012/09/02 15:33:15 2.22 +++ ray/src/rt/m_bsdf.c 2024/04/17 16:46:00 2.73 @@ -1,5 +1,5 @@ #ifndef lint -static const char RCSid[] = "$Id: m_bsdf.c,v 2.22 2012/09/02 15:33:15 greg Exp $"; +static const char RCSid[] = "$Id: m_bsdf.c,v 2.73 2024/04/17 16:46:00 greg Exp $"; #endif /* * Shading for materials with BSDFs taken from XML data files @@ -8,25 +8,26 @@ static const char RCSid[] = "$Id: m_bsdf.c,v 2.22 2012 #include "copyright.h" #include "ray.h" +#include "otypes.h" #include "ambient.h" #include "source.h" #include "func.h" #include "bsdf.h" #include "random.h" +#include "pmapmat.h" /* * Arguments to this material include optional diffuse colors. * String arguments include the BSDF and function files. - * A non-zero thickness causes the strange but useful behavior + * For the MAT_BSDF type, a non-zero thickness causes the useful behavior * of translating transmitted rays this distance beneath the surface * (opposite the surface normal) to bypass any intervening geometry. * Translation only affects scattered, non-source-directed samples. * A non-zero thickness has the further side-effect that an unscattered - * (view) ray will pass right through our material if it has any - * non-diffuse transmission, making the BSDF surface invisible. This - * shows the proxied geometry instead. Thickness has the further - * effect of turning off reflection on the hidden side so that rays - * heading in the opposite direction pass unimpeded through the BSDF + * (view) ray will pass right through our material, making the BSDF + * surface invisible and showing the proxied geometry instead. Thickness + * has the further effect of turning off reflection on the reverse side so + * rays heading in the opposite direction pass unimpeded through the BSDF * surface. A paired surface may be placed on the opposide side of * the detail geometry, less than this thickness away, if a two-way * proxy is desired. Note that the sign of the thickness is important. @@ -35,6 +36,13 @@ static const char RCSid[] = "$Id: m_bsdf.c,v 2.22 2012 * hides geometry in front of the surface when rays hit from behind, * and applies only the transmission and backside reflectance properties. * Reflection is ignored on the hidden side, as those rays pass through. + * For the MAT_ABSDF type, we check for a strong "through" component. + * Such a component will cause direct rays to pass through unscattered. + * A separate test prevents over-counting by dropping samples that are + * too close to this "through" direction. BSDFs with such a through direction + * will also have a view component, meaning they are somewhat see-through. + * A MAT_BSDF type with zero thickness behaves the same as a MAT_ABSDF + * type with no strong through component. * The "up" vector for the BSDF is given by three variables, defined * (along with the thickness) by the named function file, or '.' if none. * Together with the surface normal, this defines the local coordinate @@ -42,11 +50,18 @@ static const char RCSid[] = "$Id: m_bsdf.c,v 2.22 2012 * We do not reorient the surface, so if the BSDF has no back-side * reflectance and none is given in the real arguments, a BSDF surface * with zero thickness will appear black when viewed from behind - * unless backface visibility is off. + * unless backface visibility is on, when it becomes invisible. * The diffuse arguments are added to components in the BSDF file, * not multiplied. However, patterns affect this material as a multiplier * on everything except non-diffuse reflection. * + * Arguments for MAT_ABSDF are: + * 5+ BSDFfile ux uy uz funcfile transform + * 0 + * 0|3|6|9 rdf gdf bdf + * rdb gdb bdb + * rdt gdt bdt + * * Arguments for MAT_BSDF are: * 6+ thick BSDFfile ux uy uz funcfile transform * 0 @@ -58,7 +73,7 @@ static const char RCSid[] = "$Id: m_bsdf.c,v 2.22 2012 /* * Note that our reverse ray-tracing process means that the positions * of incoming and outgoing vectors may be reversed in our calls - * to the BSDF library. This is fine, since the bidirectional nature + * to the BSDF library. This is usually fine, since the bidirectional nature * of the BSDF (that's what the 'B' stands for) means it all works out. */ @@ -71,15 +86,138 @@ typedef struct { RREAL toloc[3][3]; /* world to local BSDF coords */ RREAL fromloc[3][3]; /* local BSDF coords to world */ double thick; /* surface thickness */ + SCOLOR cthru; /* "through" component for MAT_ABSDF */ + SCOLOR cthru_surr; /* surround for "through" component */ SDData *sd; /* loaded BSDF data */ - COLOR runsamp; /* BSDF hemispherical reflection */ - COLOR rdiff; /* added diffuse reflection */ - COLOR tunsamp; /* BSDF hemispherical transmission */ - COLOR tdiff; /* added diffuse transmission */ + SCOLOR rdiff; /* diffuse reflection */ + SCOLOR runsamp; /* BSDF hemispherical reflection */ + SCOLOR tdiff; /* diffuse transmission */ + SCOLOR tunsamp; /* BSDF hemispherical transmission */ } BSDFDAT; /* BSDF material data */ -#define cvt_sdcolor(cv, svp) ccy2rgb(&(svp)->spec, (svp)->cieY, cv) +#define cvt_sdcolor(scv, svp) ccy2scolor(&(svp)->spec, (svp)->cieY, scv) +typedef struct { + double vy; /* brightness (for sorting) */ + FVECT tdir; /* through sample direction (normalized) */ + SCOLOR vcol; /* BTDF color */ +} PEAKSAMP; /* BTDF peak sample */ + +/* Comparison function to put near-peak values in descending order */ +static int +cmp_psamp(const void *p1, const void *p2) +{ + double diff = (*(const PEAKSAMP *)p1).vy - (*(const PEAKSAMP *)p2).vy; + if (diff > 0) return(-1); + if (diff < 0) return(1); + return(0); +} + +/* Compute "through" component color for MAT_ABSDF */ +static void +compute_through(BSDFDAT *ndp) +{ +#define NDIR2CHECK 29 + static const float dir2check[NDIR2CHECK][2] = { + {0, 0}, {-0.6, 0}, {0, 0.6}, + {0, -0.6}, {0.6, 0}, {-0.6, 0.6}, + {-0.6, -0.6}, {0.6, 0.6}, {0.6, -0.6}, + {-1.2, 0}, {0, 1.2}, {0, -1.2}, + {1.2, 0}, {-1.2, 1.2}, {-1.2, -1.2}, + {1.2, 1.2}, {1.2, -1.2}, {-1.8, 0}, + {0, 1.8}, {0, -1.8}, {1.8, 0}, + {-1.8, 1.8}, {-1.8, -1.8}, {1.8, 1.8}, + {1.8, -1.8}, {-2.4, 0}, {0, 2.4}, + {0, -2.4}, {2.4, 0}, + }; + PEAKSAMP psamp[NDIR2CHECK]; + SDSpectralDF *dfp; + FVECT pdir; + double tomega, srchrad; + double tomsum, tomsurr; + SCOLOR vpeak, vsurr, btdiff; + double vypeak; + int i, ns; + SDError ec; + + if (ndp->pr->rod > 0) + dfp = (ndp->sd->tf != NULL) ? ndp->sd->tf : ndp->sd->tb; + else + dfp = (ndp->sd->tb != NULL) ? ndp->sd->tb : ndp->sd->tf; + + if (dfp == NULL) + return; /* no specular transmission */ + if (sintens(ndp->pr->pcol) <= FTINY) + return; /* pattern is black, here */ + srchrad = sqrt(dfp->minProjSA); /* else evaluate peak */ + for (i = 0; i < NDIR2CHECK; i++) { + SDValue sv; + psamp[i].tdir[0] = -ndp->vray[0] + dir2check[i][0]*srchrad; + psamp[i].tdir[1] = -ndp->vray[1] + dir2check[i][1]*srchrad; + psamp[i].tdir[2] = -ndp->vray[2]; + normalize(psamp[i].tdir); + ec = SDevalBSDF(&sv, ndp->vray, psamp[i].tdir, ndp->sd); + if (ec) + goto baderror; + cvt_sdcolor(psamp[i].vcol, &sv); + psamp[i].vy = sv.cieY; + } + qsort(psamp, NDIR2CHECK, sizeof(PEAKSAMP), cmp_psamp); + if (psamp[0].vy <= FTINY) + return; /* zero BTDF here */ + scolorblack(vpeak); + scolorblack(vsurr); + vypeak = tomsum = tomsurr = 0; /* combine top unique values */ + ns = 0; + for (i = 0; i < NDIR2CHECK; i++) { + if (i && psamp[i].vy == psamp[i-1].vy) + continue; /* assume duplicate sample */ + + ec = SDsizeBSDF(&tomega, ndp->vray, psamp[i].tdir, + SDqueryMin, ndp->sd); + if (ec) + goto baderror; + + scalescolor(psamp[i].vcol, tomega); + /* not part of peak? */ + if (tomega > 1.5*dfp->minProjSA || + vypeak > 8.*psamp[i].vy*ns) { + if (!i) return; /* abort */ + saddscolor(vsurr, psamp[i].vcol); + tomsurr += tomega; + continue; + } + saddscolor(vpeak, psamp[i].vcol); + tomsum += tomega; + vypeak += psamp[i].vy; + ++ns; + } + if (tomsurr < 0.2*tomsum) /* insufficient surround? */ + return; + scalescolor(vsurr, 1./tomsurr); /* surround is avg. BTDF */ + if (ndp->vray[2] > 0) /* get diffuse BTDF */ + cvt_sdcolor(btdiff, &ndp->sd->tLambFront); + else + cvt_sdcolor(btdiff, &ndp->sd->tLambBack); + scalescolor(btdiff, (1./PI)); + for (i = NCSAMP; i--; ) { /* remove diffuse contrib. */ + if ((vpeak[i] -= tomsum*btdiff[i]) < 0) + vpeak[i] = 0; + if ((vsurr[i] -= btdiff[i]) < 0) + vsurr[i] = 0; + } + if (pbright(vpeak) < .0005) /* < 0.05% specular? */ + return; + smultscolor(vsurr, ndp->pr->pcol); /* modify by pattern */ + smultscolor(vpeak, ndp->pr->pcol); + copyscolor(ndp->cthru_surr, vsurr); + copyscolor(ndp->cthru, vpeak); + return; +baderror: + objerror(ndp->mp, USER, transSDError(ec)); +#undef NDIR2CHECK +} + /* Jitter ray sample according to projected solid angle and specjitter */ static void bsdf_jitter(FVECT vres, BSDFDAT *ndp, double sr_psa) @@ -94,67 +232,108 @@ bsdf_jitter(FVECT vres, BSDFDAT *ndp, double sr_psa) normalize(vres); } -/* Evaluate BSDF for direct component, returning true if OK to proceed */ +/* Get BSDF specular for direct component, returning true if OK to proceed */ static int -direct_bsdf_OK(COLOR cval, FVECT ldir, double omega, BSDFDAT *ndp) +direct_specular_OK(SCOLOR scval, FVECT ldir, double omega, BSDFDAT *ndp) { - int nsamp, ok = 0; - FVECT vsrc, vsmp, vjit; - double tomega; - double sf, tsr, sd[2]; - COLOR csmp; + int nsamp = 1; + int scnt = 0; + FVECT vsrc, vjit; + double tomega, tomega2; + double tsr, sd[2]; + SCOLOR csmp, cdiff; + double diffY; SDValue sv; SDError ec; int i; + /* in case we fail */ + scolorblack(scval); /* transform source direction */ if (SDmapDir(vsrc, ndp->toloc, ldir) != SDEnone) return(0); - /* assign number of samples */ + /* check indirect over-counting */ + if ((vsrc[2] > 0) ^ (ndp->vray[2] > 0) && sintens(ndp->cthru) > FTINY) { + double dx = vsrc[0] + ndp->vray[0]; + double dy = vsrc[1] + ndp->vray[1]; + SDSpectralDF *dfp = (ndp->pr->rod > 0) ? + ((ndp->sd->tf != NULL) ? ndp->sd->tf : ndp->sd->tb) : + ((ndp->sd->tb != NULL) ? ndp->sd->tb : ndp->sd->tf) ; + + tomega = omega*fabs(vsrc[2]); + if (dx*dx + dy*dy <= (2.5*4./PI)*(tomega + dfp->minProjSA + + 2.*sqrt(tomega*dfp->minProjSA))) { + if (sintens(ndp->cthru_surr) <= FTINY) + return(0); + copyscolor(scval, ndp->cthru_surr); + return(1); /* return non-zero surround BTDF */ + } + } + /* will discount diffuse portion */ + switch ((vsrc[2] > 0)<<1 | (ndp->vray[2] > 0)) { + case 3: + if (ndp->sd->rf == NULL) + return(0); /* all diffuse */ + sv = ndp->sd->rLambFront; + break; + case 0: + if (ndp->sd->rb == NULL) + return(0); /* all diffuse */ + sv = ndp->sd->rLambBack; + break; + case 1: + if ((ndp->sd->tf == NULL) & (ndp->sd->tb == NULL)) + return(0); /* all diffuse */ + sv = ndp->sd->tLambFront; + break; + case 2: + if ((ndp->sd->tf == NULL) & (ndp->sd->tb == NULL)) + return(0); /* all diffuse */ + sv = ndp->sd->tLambBack; + break; + } + if (sv.cieY > FTINY) { + diffY = sv.cieY *= 1./PI; + cvt_sdcolor(cdiff, &sv); + } else { + diffY = 0; + scolorblack(cdiff); + } ec = SDsizeBSDF(&tomega, ndp->vray, vsrc, SDqueryMin, ndp->sd); if (ec) goto baderror; - /* check indirect over-counting */ - if (ndp->thick != 0 && ndp->pr->crtype & (SPECULAR|AMBIENT) - && vsrc[2] > 0 ^ ndp->vray[2] > 0) { - double dx = vsrc[0] + ndp->vray[0]; - double dy = vsrc[1] + ndp->vray[1]; - if (dx*dx + dy*dy <= omega+tomega) - return(0); + /* check if sampling BSDF */ + if ((tsr = sqrt(tomega)) > 0) { + nsamp = 4.*specjitter*ndp->pr->rweight + .5; + nsamp += !nsamp; } - sf = specjitter * ndp->pr->rweight; - if (25.*tomega <= omega) - nsamp = 100.*sf + .5; - else - nsamp = 4.*sf*omega/tomega + .5; - nsamp += !nsamp; - setcolor(cval, .0, .0, .0); /* sample our source area */ - sf = sqrt(omega); - tsr = sqrt(tomega); + /* jitter to fuzz BSDF cells */ for (i = nsamp; i--; ) { - VCOPY(vsmp, vsrc); /* jitter query directions */ - if (nsamp > 1) { - multisamp(sd, 2, (i + frandom())/(double)nsamp); - vsmp[0] += (sd[0] - .5)*sf; - vsmp[1] += (sd[1] - .5)*sf; - if (normalize(vsmp) == 0) { - --nsamp; - continue; - } - } bsdf_jitter(vjit, ndp, tsr); /* compute BSDF */ - ec = SDevalBSDF(&sv, vjit, vsmp, ndp->sd); + ec = SDevalBSDF(&sv, vjit, vsrc, ndp->sd); if (ec) goto baderror; - if (sv.cieY <= FTINY) /* worth using? */ - continue; + if (sv.cieY - diffY <= FTINY) + continue; /* no specular part */ + /* check for variable resolution */ + ec = SDsizeBSDF(&tomega2, vjit, vsrc, SDqueryMin, ndp->sd); + if (ec) + goto baderror; + if (tomega2 < .12*tomega) + continue; /* not safe to include */ cvt_sdcolor(csmp, &sv); - addcolor(cval, csmp); /* average it in */ - ++ok; + saddscolor(scval, csmp); + ++scnt; } - sf = 1./(double)nsamp; - scalecolor(cval, sf); - return(ok); + if (!scnt) /* no valid specular samples? */ + return(0); + + scalescolor(scval, 1./scnt); /* weighted average BSDF */ + /* subtract diffuse contribution */ + for (i = NCSAMP*(diffY > FTINY); i--; ) + if ((scval[i] -= cdiff[i]) < 0) + scval[i] = 0; + return(1); baderror: objerror(ndp->mp, USER, transSDError(ec)); return(0); /* gratis return */ @@ -163,7 +342,7 @@ baderror: /* Compute source contribution for BSDF (reflected & transmitted) */ static void dir_bsdf( - COLOR cval, /* returned coefficient */ + SCOLOR scval, /* returned coefficient */ void *nnp, /* material data */ FVECT ldir, /* light source direction */ double omega /* light source size */ @@ -172,61 +351,52 @@ dir_bsdf( BSDFDAT *np = (BSDFDAT *)nnp; double ldot; double dtmp; - COLOR ctmp; + SCOLOR sctmp; - setcolor(cval, .0, .0, .0); + scolorblack(scval); ldot = DOT(np->pnorm, ldir); if ((-FTINY <= ldot) & (ldot <= FTINY)) return; - if (ldot > 0 && bright(np->rdiff) > FTINY) { + if (ldot > 0 && sintens(np->rdiff) > FTINY) { /* - * Compute added diffuse reflected component. + * Compute diffuse reflected component */ - copycolor(ctmp, np->rdiff); + copyscolor(sctmp, np->rdiff); dtmp = ldot * omega * (1./PI); - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } - if (ldot < 0 && bright(np->tdiff) > FTINY) { + if (ldot < 0 && sintens(np->tdiff) > FTINY) { /* - * Compute added diffuse transmission. + * Compute diffuse transmission */ - copycolor(ctmp, np->tdiff); - dtmp = -ldot * omega * (1.0/PI); - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + copyscolor(sctmp, np->tdiff); + dtmp = -ldot * omega * (1./PI); + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } + if (ambRayInPmap(np->pr)) + return; /* specular already in photon map */ /* - * Compute scattering coefficient using BSDF. + * Compute specular scattering coefficient using BSDF */ - if (!direct_bsdf_OK(ctmp, ldir, omega, np)) + if (!direct_specular_OK(sctmp, ldir, omega, np)) return; - if (ldot > 0) { /* pattern only diffuse reflection */ - COLOR ctmp1, ctmp2; - dtmp = (np->pr->rod > 0) ? np->sd->rLambFront.cieY - : np->sd->rLambBack.cieY; - /* diffuse fraction */ - dtmp /= PI * bright(ctmp); - copycolor(ctmp2, np->pr->pcol); - scalecolor(ctmp2, dtmp); - setcolor(ctmp1, 1.-dtmp, 1.-dtmp, 1.-dtmp); - addcolor(ctmp1, ctmp2); - multcolor(ctmp, ctmp1); /* apply derated pattern */ - dtmp = ldot * omega; - } else { /* full pattern on transmission */ - multcolor(ctmp, np->pr->pcol); + if (ldot < 0) { /* pattern for specular transmission */ + smultscolor(sctmp, np->pr->pcol); dtmp = -ldot * omega; - } - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + } else + dtmp = ldot * omega; + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } /* Compute source contribution for BSDF (reflected only) */ static void dir_brdf( - COLOR cval, /* returned coefficient */ + SCOLOR scval, /* returned coefficient */ void *nnp, /* material data */ FVECT ldir, /* light source direction */ double omega /* light source size */ @@ -235,47 +405,40 @@ dir_brdf( BSDFDAT *np = (BSDFDAT *)nnp; double ldot; double dtmp; - COLOR ctmp, ctmp1, ctmp2; + SCOLOR sctmp; - setcolor(cval, .0, .0, .0); + scolorblack(scval); ldot = DOT(np->pnorm, ldir); if (ldot <= FTINY) return; - if (bright(np->rdiff) > FTINY) { + if (sintens(np->rdiff) > FTINY) { /* - * Compute added diffuse reflected component. + * Compute diffuse reflected component */ - copycolor(ctmp, np->rdiff); + copyscolor(sctmp, np->rdiff); dtmp = ldot * omega * (1./PI); - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } + if (ambRayInPmap(np->pr)) + return; /* specular already in photon map */ /* - * Compute reflection coefficient using BSDF. + * Compute specular reflection coefficient using BSDF */ - if (!direct_bsdf_OK(ctmp, ldir, omega, np)) + if (!direct_specular_OK(sctmp, ldir, omega, np)) return; - /* pattern only diffuse reflection */ - dtmp = (np->pr->rod > 0) ? np->sd->rLambFront.cieY - : np->sd->rLambBack.cieY; - dtmp /= PI * bright(ctmp); /* diffuse fraction */ - copycolor(ctmp2, np->pr->pcol); - scalecolor(ctmp2, dtmp); - setcolor(ctmp1, 1.-dtmp, 1.-dtmp, 1.-dtmp); - addcolor(ctmp1, ctmp2); - multcolor(ctmp, ctmp1); /* apply derated pattern */ dtmp = ldot * omega; - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } /* Compute source contribution for BSDF (transmitted only) */ static void dir_btdf( - COLOR cval, /* returned coefficient */ + SCOLOR scval, /* returned coefficient */ void *nnp, /* material data */ FVECT ldir, /* light source direction */ double omega /* light source size */ @@ -284,88 +447,105 @@ dir_btdf( BSDFDAT *np = (BSDFDAT *)nnp; double ldot; double dtmp; - COLOR ctmp; + SCOLOR sctmp; - setcolor(cval, .0, .0, .0); + scolorblack(scval); ldot = DOT(np->pnorm, ldir); if (ldot >= -FTINY) return; - if (bright(np->tdiff) > FTINY) { + if (sintens(np->tdiff) > FTINY) { /* - * Compute added diffuse transmission. + * Compute diffuse transmission */ - copycolor(ctmp, np->tdiff); - dtmp = -ldot * omega * (1.0/PI); - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + copyscolor(sctmp, np->tdiff); + dtmp = -ldot * omega * (1./PI); + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } + if (ambRayInPmap(np->pr)) + return; /* specular already in photon map */ /* - * Compute scattering coefficient using BSDF. + * Compute specular scattering coefficient using BSDF */ - if (!direct_bsdf_OK(ctmp, ldir, omega, np)) + if (!direct_specular_OK(sctmp, ldir, omega, np)) return; /* full pattern on transmission */ - multcolor(ctmp, np->pr->pcol); + smultscolor(sctmp, np->pr->pcol); dtmp = -ldot * omega; - scalecolor(ctmp, dtmp); - addcolor(cval, ctmp); + scalescolor(sctmp, dtmp); + saddscolor(scval, sctmp); } /* Sample separate BSDF component */ static int -sample_sdcomp(BSDFDAT *ndp, SDComponent *dcp, int usepat) +sample_sdcomp(BSDFDAT *ndp, SDComponent *dcp, int xmit) { - int nstarget = 1; - int nsent; - SDError ec; - SDValue bsv; - double xrand; - FVECT vsmp; - RAY sr; + const int hasthru = (xmit && + !(ndp->pr->crtype & (SPECULAR|AMBIENT)) + && sintens(ndp->cthru) > FTINY); + int nstarget = 1; + int nsent = 0; + int n; + SDError ec; + SDValue bsv; + double xrand; + FVECT vsmp, vinc; + RAY sr; /* multiple samples? */ if (specjitter > 1.5) { nstarget = specjitter*ndp->pr->rweight + .5; nstarget += !nstarget; } /* run through our samples */ - for (nsent = 0; nsent < nstarget; nsent++) { + for (n = 0; n < nstarget; n++) { if (nstarget == 1) { /* stratify random variable */ xrand = urand(ilhash(dimlist,ndims)+samplendx); if (specjitter < 1.) xrand = .5 + specjitter*(xrand-.5); } else { - xrand = (nsent + frandom())/(double)nstarget; + xrand = (n + frandom())/(double)nstarget; } SDerrorDetail[0] = '\0'; /* sample direction & coef. */ bsdf_jitter(vsmp, ndp, ndp->sr_vpsa[0]); + VCOPY(vinc, vsmp); /* to compare after */ ec = SDsampComponent(&bsv, vsmp, xrand, dcp); if (ec) objerror(ndp->mp, USER, transSDError(ec)); if (bsv.cieY <= FTINY) /* zero component? */ break; - /* map vector to world */ + if (hasthru) { /* check for view ray */ + double dx = vinc[0] + vsmp[0]; + double dy = vinc[1] + vsmp[1]; + if (dx*dx + dy*dy <= ndp->sr_vpsa[0]*ndp->sr_vpsa[0]) + continue; /* exclude view sample */ + } + /* map non-view sample->world */ if (SDmapDir(sr.rdir, ndp->fromloc, vsmp) != SDEnone) break; /* spawn a specular ray */ if (nstarget > 1) bsv.cieY /= (double)nstarget; cvt_sdcolor(sr.rcoef, &bsv); /* use sample color */ - if (usepat) /* apply pattern? */ - multcolor(sr.rcoef, ndp->pr->pcol); - if (rayorigin(&sr, SPECULAR, ndp->pr, sr.rcoef) < 0) { - if (maxdepth > 0) - break; - continue; /* Russian roulette victim */ + if (xmit) /* apply pattern on transmit */ + smultscolor(sr.rcoef, ndp->pr->pcol); + if (rayorigin(&sr, xmit ? TSPECULAR : RSPECULAR, ndp->pr, sr.rcoef) < 0) { + if (!n & (nstarget > 1)) { + n = nstarget; /* avoid infinitue loop */ + nstarget = nstarget*sr.rweight/(minweight + 1e-20); + if (n == nstarget) break; + n = -1; /* moved target */ + } + continue; /* try again */ } - /* need to offset origin? */ - if (ndp->thick != 0 && ndp->pr->rod > 0 ^ vsmp[2] > 0) + if (xmit && ndp->thick != 0) /* need to offset origin? */ VSUM(sr.rorg, sr.rorg, ndp->pr->ron, -ndp->thick); rayvalue(&sr); /* send & evaluate sample */ - multcolor(sr.rcol, sr.rcoef); - addcolor(ndp->pr->rcol, sr.rcol); + smultscolor(sr.rcol, sr.rcoef); + saddscolor(ndp->pr->rcol, sr.rcol); + ++nsent; } return(nsent); } @@ -374,7 +554,11 @@ sample_sdcomp(BSDFDAT *ndp, SDComponent *dcp, int usep static int sample_sdf(BSDFDAT *ndp, int sflags) { + int hasthru = (sflags == SDsampSpT && + !(ndp->pr->crtype & (SPECULAR|AMBIENT)) + && sintens(ndp->cthru) > FTINY); int n, ntotal = 0; + double b = 0; SDSpectralDF *dfp; COLORV *unsc; @@ -384,40 +568,50 @@ sample_sdf(BSDFDAT *ndp, int sflags) dfp = (ndp->sd->tf != NULL) ? ndp->sd->tf : ndp->sd->tb; else dfp = (ndp->sd->tb != NULL) ? ndp->sd->tb : ndp->sd->tf; - cvt_sdcolor(unsc, &ndp->sd->tLamb); } else /* sflags == SDsampSpR */ { unsc = ndp->runsamp; - if (ndp->pr->rod > 0) { + if (ndp->pr->rod > 0) dfp = ndp->sd->rf; - cvt_sdcolor(unsc, &ndp->sd->rLambFront); - } else { + else dfp = ndp->sd->rb; - cvt_sdcolor(unsc, &ndp->sd->rLambBack); - } } - multcolor(unsc, ndp->pr->pcol); + scolorblack(unsc); if (dfp == NULL) /* no specular component? */ return(0); - /* below sampling threshold? */ - if (dfp->maxHemi <= specthresh+FTINY) { - if (dfp->maxHemi > FTINY) { /* XXX no color from BSDF */ - FVECT vjit; - double d; - COLOR ctmp; - bsdf_jitter(vjit, ndp, ndp->sr_vpsa[1]); - d = SDdirectHemi(vjit, sflags, ndp->sd); + + if (hasthru) { /* separate view sample? */ + RAY tr; + if (rayorigin(&tr, TRANS, ndp->pr, ndp->cthru) == 0) { + VCOPY(tr.rdir, ndp->pr->rdir); + rayvalue(&tr); + smultscolor(tr.rcol, tr.rcoef); + saddscolor(ndp->pr->rcol, tr.rcol); + ndp->pr->rxt = ndp->pr->rot + raydistance(&tr); + ++ntotal; + b = pbright(ndp->cthru); + } else + hasthru = 0; + } + if (dfp->maxHemi - b <= FTINY) { /* have specular to sample? */ + b = 0; + } else { + FVECT vjit; + bsdf_jitter(vjit, ndp, ndp->sr_vpsa[1]); + b = SDdirectHemi(vjit, sflags, ndp->sd) - b; + b *= (b > 0); + } + if (b <= specthresh+FTINY) { /* below sampling threshold? */ + if (b > FTINY) { /* XXX no color from BSDF */ if (sflags == SDsampSpT) { - copycolor(ctmp, ndp->pr->pcol); - scalecolor(ctmp, d); + copyscolor(unsc, ndp->pr->pcol); + scalescolor(unsc, b); } else /* no pattern on reflection */ - setcolor(ctmp, d, d, d); - addcolor(unsc, ctmp); + setscolor(unsc, b, b, b); } - return(0); + return(ntotal); } - /* else need to sample */ - dimlist[ndims++] = (int)(size_t)ndp->mp; - ndims++; + dimlist[ndims] = (int)(size_t)ndp->mp; /* else sample specular */ + ndims += 2; for (n = dfp->ncomp; n--; ) { /* loop over components */ dimlist[ndims-1] = n + 9438; ntotal += sample_sdcomp(ndp, &dfp->comp[n], sflags==SDsampSpT); @@ -430,83 +624,96 @@ sample_sdf(BSDFDAT *ndp, int sflags) int m_bsdf(OBJREC *m, RAY *r) { + int hasthick = (m->otype == MAT_BSDF); int hitfront; - COLOR ctmp; + SCOLOR sctmp; SDError ec; FVECT upvec, vtmp; MFUNC *mf; BSDFDAT nd; /* check arguments */ - if ((m->oargs.nsargs < 6) | (m->oargs.nfargs > 9) | + if ((m->oargs.nsargs < hasthick+5) | (m->oargs.nfargs > 9) | (m->oargs.nfargs % 3)) objerror(m, USER, "bad # arguments"); /* record surface struck */ hitfront = (r->rod > 0); /* load cal file */ - mf = getfunc(m, 5, 0x1d, 1); - /* get thickness */ - nd.thick = evalue(mf->ep[0]); - if ((-FTINY <= nd.thick) & (nd.thick <= FTINY)) - nd.thick = .0; - /* check shadow */ - if (r->crtype & SHADOW) { - if (nd.thick != 0) - raytrans(r); /* pass-through */ - return(1); /* or shadow */ + mf = hasthick ? getfunc(m, 5, 0x1d, 1) + : getfunc(m, 4, 0xe, 1) ; + setfunc(m, r); + nd.thick = 0; /* set thickness */ + if (hasthick) { + nd.thick = evalue(mf->ep[0]); + if ((-FTINY <= nd.thick) & (nd.thick <= FTINY)) + nd.thick = 0; } + /* check backface visibility */ + if (!hitfront & !backvis) { + raytrans(r); + return(1); + } /* check other rays to pass */ - if (nd.thick != 0 && (!(r->crtype & (SPECULAR|AMBIENT)) || - nd.thick > 0 ^ hitfront)) { + if (nd.thick != 0 && (r->crtype & SHADOW || + !(r->crtype & (SPECULAR|AMBIENT)) || + (nd.thick > 0) ^ hitfront)) { raytrans(r); /* hide our proxy */ return(1); } + if (hasthick && r->crtype & SHADOW) /* early shadow check #1 */ + return(1); + nd.mp = m; + nd.pr = r; /* get BSDF data */ - nd.sd = loadBSDF(m->oargs.sarg[1]); - /* diffuse reflectance */ + nd.sd = loadBSDF(m->oargs.sarg[hasthick]); + /* early shadow check #2 */ + if (r->crtype & SHADOW && (nd.sd->tf == NULL) & (nd.sd->tb == NULL)) { + SDfreeCache(nd.sd); + return(1); + } + /* diffuse components */ if (hitfront) { - if (m->oargs.nfargs < 3) - setcolor(nd.rdiff, .0, .0, .0); - else - setcolor(nd.rdiff, m->oargs.farg[0], + cvt_sdcolor(nd.rdiff, &nd.sd->rLambFront); + if (m->oargs.nfargs >= 3) { + setscolor(sctmp, m->oargs.farg[0], m->oargs.farg[1], m->oargs.farg[2]); + saddscolor(nd.rdiff, sctmp); + } + cvt_sdcolor(nd.tdiff, &nd.sd->tLambFront); } else { - if (m->oargs.nfargs < 6) { /* check invisible backside */ - if (!backvis && (nd.sd->rb == NULL) & - (nd.sd->tb == NULL)) { - SDfreeCache(nd.sd); - raytrans(r); - return(1); - } - setcolor(nd.rdiff, .0, .0, .0); - } else - setcolor(nd.rdiff, m->oargs.farg[3], + cvt_sdcolor(nd.rdiff, &nd.sd->rLambBack); + if (m->oargs.nfargs >= 6) { + setscolor(sctmp, m->oargs.farg[3], m->oargs.farg[4], m->oargs.farg[5]); + saddscolor(nd.rdiff, sctmp); + } + cvt_sdcolor(nd.tdiff, &nd.sd->tLambBack); } - /* diffuse transmittance */ - if (m->oargs.nfargs < 9) - setcolor(nd.tdiff, .0, .0, .0); - else - setcolor(nd.tdiff, m->oargs.farg[6], + if (m->oargs.nfargs >= 9) { /* add diffuse transmittance? */ + setscolor(sctmp, m->oargs.farg[6], m->oargs.farg[7], m->oargs.farg[8]); - nd.mp = m; - nd.pr = r; + saddscolor(nd.tdiff, sctmp); + } /* get modifiers */ raytexture(r, m->omod); /* modify diffuse values */ - multcolor(nd.rdiff, r->pcol); - multcolor(nd.tdiff, r->pcol); + smultscolor(nd.rdiff, r->pcol); + smultscolor(nd.tdiff, r->pcol); /* get up vector */ - upvec[0] = evalue(mf->ep[1]); - upvec[1] = evalue(mf->ep[2]); - upvec[2] = evalue(mf->ep[3]); + upvec[0] = evalue(mf->ep[hasthick+0]); + upvec[1] = evalue(mf->ep[hasthick+1]); + upvec[2] = evalue(mf->ep[hasthick+2]); /* return to world coords */ if (mf->fxp != &unitxf) { multv3(upvec, upvec, mf->fxp->xfm); nd.thick *= mf->fxp->sca; } + if (r->rox != NULL) { + multv3(upvec, upvec, r->rox->f.xfm); + nd.thick *= r->rox->f.sca; + } raynormal(nd.pnorm, r); /* compute local BSDF xform */ ec = SDcompXform(nd.toloc, nd.pnorm, upvec); @@ -516,14 +723,31 @@ m_bsdf(OBJREC *m, RAY *r) nd.vray[2] = -r->rdir[2]; ec = SDmapDir(nd.vray, nd.toloc, nd.vray); } - if (!ec) - ec = SDinvXform(nd.fromloc, nd.toloc); if (ec) { objerror(m, WARNING, "Illegal orientation vector"); + SDfreeCache(nd.sd); return(1); } - /* determine BSDF resolution */ - ec = SDsizeBSDF(nd.sr_vpsa, nd.vray, NULL, SDqueryMin+SDqueryMax, nd.sd); + scolorblack(nd.cthru); /* consider through component */ + scolorblack(nd.cthru_surr); + if (m->otype == MAT_ABSDF) { + compute_through(&nd); + if (r->crtype & SHADOW) { + RAY tr; /* attempt to pass shadow ray */ + SDfreeCache(nd.sd); + if (rayorigin(&tr, TRANS, r, nd.cthru) < 0) + return(1); /* no through component */ + VCOPY(tr.rdir, r->rdir); + rayvalue(&tr); /* transmit with scaling */ + smultscolor(tr.rcol, tr.rcoef); + copyscolor(r->rcol, tr.rcol); + return(1); /* we're done */ + } + } + ec = SDinvXform(nd.fromloc, nd.toloc); + if (!ec) /* determine BSDF resolution */ + ec = SDsizeBSDF(nd.sr_vpsa, nd.vray, NULL, + SDqueryMin+SDqueryMax, nd.sd); if (ec) objerror(m, USER, transSDError(ec)); @@ -539,39 +763,31 @@ m_bsdf(OBJREC *m, RAY *r) /* sample transmission */ sample_sdf(&nd, SDsampSpT); /* compute indirect diffuse */ - copycolor(ctmp, nd.rdiff); - addcolor(ctmp, nd.runsamp); - if (bright(ctmp) > FTINY) { /* ambient from reflection */ - if (!hitfront) - flipsurface(r); - multambient(ctmp, r, nd.pnorm); - addcolor(r->rcol, ctmp); - if (!hitfront) - flipsurface(r); + copyscolor(sctmp, nd.rdiff); + saddscolor(sctmp, nd.runsamp); + if (sintens(sctmp) > FTINY) { /* ambient from reflection */ + multambient(sctmp, r, nd.pnorm); + saddscolor(r->rcol, sctmp); } - copycolor(ctmp, nd.tdiff); - addcolor(ctmp, nd.tunsamp); - if (bright(ctmp) > FTINY) { /* ambient from other side */ + copyscolor(sctmp, nd.tdiff); + saddscolor(sctmp, nd.tunsamp); + if (sintens(sctmp) > FTINY) { /* ambient from other side */ FVECT bnorm; - if (hitfront) - flipsurface(r); bnorm[0] = -nd.pnorm[0]; bnorm[1] = -nd.pnorm[1]; bnorm[2] = -nd.pnorm[2]; if (nd.thick != 0) { /* proxy with offset? */ VCOPY(vtmp, r->rop); VSUM(r->rop, vtmp, r->ron, nd.thick); - multambient(ctmp, r, bnorm); + multambient(sctmp, r, bnorm); VCOPY(r->rop, vtmp); } else - multambient(ctmp, r, bnorm); - addcolor(r->rcol, ctmp); - if (hitfront) - flipsurface(r); + multambient(sctmp, r, bnorm); + saddscolor(r->rcol, sctmp); } /* add direct component */ - if ((bright(nd.tdiff) <= FTINY) & (nd.sd->tf == NULL) & - (nd.sd->tb == NULL)) { + if ((nd.sd->tf == NULL) & (nd.sd->tb == NULL) && + sintens(nd.tdiff) <= FTINY) { direct(r, dir_brdf, &nd); /* reflection only */ } else if (nd.thick == 0) { direct(r, dir_bsdf, &nd); /* thin surface scattering */