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/* Copyright (c) 1996 Regents of the University of California */ |
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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static const char RCSid[] = "$Id$"; |
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#endif |
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|
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/* |
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* normal.c - shading function for normal materials. |
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* |
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* Later changes described in delta comments. |
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*/ |
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|
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#include "ray.h" |
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#include "copyright.h" |
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|
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#include "ray.h" |
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#include "ambient.h" |
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#include "source.h" |
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#include "otypes.h" |
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#include "rtotypes.h" |
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#include "random.h" |
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|
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extern double specthresh; /* specular sampling threshold */ |
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extern double specjitter; /* specular sampling jitter */ |
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|
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extern int backvis; /* back faces visible? */ |
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|
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#ifndef MAXITER |
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#define MAXITER 10 /* maximum # specular ray attempts */ |
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#endif |
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/* estimate of Fresnel function */ |
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#define FRESNE(ci) (exp(-5.85*(ci)) - 0.00287989916) |
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#define FRESTHRESH 0.017999 /* minimum specularity for approx. */ |
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|
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static gaussamp(); |
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|
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/* |
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* This routine implements the isotropic Gaussian |
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double pdot; /* perturbed dot product */ |
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} NORMDAT; /* normal material data */ |
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|
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static srcdirf_t dirnorm; |
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static void gaussamp(RAY *r, NORMDAT *np); |
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|
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dirnorm(cval, np, ldir, omega) /* compute source contribution */ |
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COLOR cval; /* returned coefficient */ |
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register NORMDAT *np; /* material data */ |
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FVECT ldir; /* light source direction */ |
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double omega; /* light source size */ |
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|
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static void |
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dirnorm( /* compute source contribution */ |
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COLOR cval, /* returned coefficient */ |
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void *nnp, /* material data */ |
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FVECT ldir, /* light source direction */ |
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double omega /* light source size */ |
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) |
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{ |
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register NORMDAT *np = nnp; |
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double ldot; |
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double dtmp, d2; |
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double lrdiff, ltdiff; |
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double dtmp, d2, d3, d4; |
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FVECT vtmp; |
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COLOR ctmp; |
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|
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if (ldot < 0.0 ? np->trans <= FTINY : np->trans >= 1.0-FTINY) |
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return; /* wrong side */ |
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|
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if (ldot > FTINY && np->rdiff > FTINY) { |
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/* Fresnel estimate */ |
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lrdiff = np->rdiff; |
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ltdiff = np->tdiff; |
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if (np->specfl & SP_PURE && np->rspec >= FRESTHRESH && |
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(lrdiff > FTINY) | (ltdiff > FTINY)) { |
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dtmp = 1. - FRESNE(fabs(ldot)); |
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lrdiff *= dtmp; |
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ltdiff *= dtmp; |
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} |
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|
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if (ldot > FTINY && lrdiff > FTINY) { |
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/* |
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* Compute and add diffuse reflected component to returned |
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* color. The diffuse reflected component will always be |
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* modified by the color of the material. |
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*/ |
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copycolor(ctmp, np->mcolor); |
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dtmp = ldot * omega * np->rdiff / PI; |
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dtmp = ldot * omega * lrdiff * (1.0/PI); |
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scalecolor(ctmp, dtmp); |
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addcolor(cval, ctmp); |
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} |
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if (ldot > FTINY && (np->specfl&(SP_REFL|SP_PURE)) == SP_REFL) { |
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/* |
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* Compute specular reflection coefficient using |
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* gaussian distribution model. |
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* Gaussian distribution model. |
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*/ |
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/* roughness */ |
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dtmp = np->alpha2; |
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/* + source if flat */ |
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if (np->specfl & SP_FLAT) |
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dtmp += omega/(4.0*PI); |
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dtmp += omega * (0.25/PI); |
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/* half vector */ |
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vtmp[0] = ldir[0] - np->rp->rdir[0]; |
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vtmp[1] = ldir[1] - np->rp->rdir[1]; |
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vtmp[2] = ldir[2] - np->rp->rdir[2]; |
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d2 = DOT(vtmp, np->pnorm); |
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d2 *= d2; |
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d2 = (DOT(vtmp,vtmp) - d2) / d2; |
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/* gaussian */ |
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dtmp = exp(-d2/dtmp)/(4.*PI*dtmp); |
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d3 = DOT(vtmp,vtmp); |
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d4 = (d3 - d2) / d2; |
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/* new W-G-M-D model */ |
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dtmp = exp(-d4/dtmp) * d3 / (PI * d2*d2 * dtmp); |
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/* worth using? */ |
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if (dtmp > FTINY) { |
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copycolor(ctmp, np->scolor); |
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dtmp *= omega * sqrt(ldot/np->pdot); |
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dtmp *= ldot * omega; |
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scalecolor(ctmp, dtmp); |
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addcolor(cval, ctmp); |
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} |
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} |
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if (ldot < -FTINY && np->tdiff > FTINY) { |
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if (ldot < -FTINY && ltdiff > FTINY) { |
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/* |
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* Compute diffuse transmission. |
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*/ |
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copycolor(ctmp, np->mcolor); |
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dtmp = -ldot * omega * np->tdiff / PI; |
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dtmp = -ldot * omega * ltdiff * (1.0/PI); |
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scalecolor(ctmp, dtmp); |
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addcolor(cval, ctmp); |
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} |
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* is always modified by material color. |
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*/ |
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/* roughness + source */ |
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dtmp = np->alpha2 + omega/PI; |
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/* gaussian */ |
158 |
> |
dtmp = np->alpha2 + omega*(1.0/PI); |
159 |
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/* Gaussian */ |
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dtmp = exp((2.*DOT(np->prdir,ldir)-2.)/dtmp)/(PI*dtmp); |
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/* worth using? */ |
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if (dtmp > FTINY) { |
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} |
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|
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|
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m_normal(m, r) /* color a ray that hit something normal */ |
173 |
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register OBJREC *m; |
174 |
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register RAY *r; |
172 |
> |
extern int |
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m_normal( /* color a ray that hit something normal */ |
174 |
> |
register OBJREC *m, |
175 |
> |
register RAY *r |
176 |
> |
) |
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{ |
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NORMDAT nd; |
179 |
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double fest; |
180 |
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double transtest, transdist; |
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double mirtest, mirdist; |
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int hastexture; |
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raytrans(r); |
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return(1); |
197 |
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} |
198 |
+ |
raytexture(r, m->omod); |
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flipsurface(r); /* reorient if backvis */ |
200 |
< |
} |
200 |
> |
} else |
201 |
> |
raytexture(r, m->omod); |
202 |
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nd.mp = m; |
203 |
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nd.rp = r; |
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/* get material color */ |
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nd.alpha2 = m->oargs.farg[4]; |
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if ((nd.alpha2 *= nd.alpha2) <= FTINY) |
212 |
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nd.specfl |= SP_PURE; |
213 |
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if (r->ro != NULL && isflat(r->ro->otype)) |
214 |
< |
nd.specfl |= SP_FLAT; |
195 |
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/* get modifiers */ |
196 |
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raytexture(r, m->omod); |
197 |
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if (hastexture = DOT(r->pert,r->pert) > FTINY*FTINY) |
213 |
> |
|
214 |
> |
if ( (hastexture = (DOT(r->pert,r->pert) > FTINY*FTINY)) ) { |
215 |
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nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */ |
216 |
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else { |
216 |
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} else { |
217 |
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VCOPY(nd.pnorm, r->ron); |
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nd.pdot = r->rod; |
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} |
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if (r->ro != NULL && isflat(r->ro->otype)) |
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nd.specfl |= SP_FLAT; |
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if (nd.pdot < .001) |
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nd.pdot = .001; /* non-zero for dirnorm() */ |
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multcolor(nd.mcolor, r->pcol); /* modify material color */ |
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mirtest = transtest = 0; |
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mirdist = transdist = r->rot; |
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nd.rspec = m->oargs.farg[3]; |
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/* compute Fresnel approx. */ |
229 |
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if (nd.specfl & SP_PURE && nd.rspec >= FRESTHRESH) { |
230 |
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fest = FRESNE(r->rod); |
231 |
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nd.rspec += fest*(1. - nd.rspec); |
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} else |
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fest = 0.; |
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/* compute transmission */ |
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if (m->otype == MAT_TRANS) { |
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nd.trans = m->oargs.farg[5]*(1.0 - nd.rspec); |
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} else |
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nd.tdiff = nd.tspec = nd.trans = 0.0; |
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/* transmitted ray */ |
260 |
< |
if (nd.specfl&SP_TRAN && (nd.specfl&SP_PURE || r->crtype&SHADOW)) { |
260 |
> |
if ((nd.specfl&(SP_TRAN|SP_PURE|SP_TBLT)) == (SP_TRAN|SP_PURE)) { |
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RAY lr; |
262 |
< |
if (rayorigin(&lr, r, TRANS, nd.tspec) == 0) { |
262 |
> |
copycolor(lr.rcoef, nd.mcolor); /* modified by color */ |
263 |
> |
scalecolor(lr.rcoef, nd.tspec); |
264 |
> |
if (rayorigin(&lr, TRANS, r, lr.rcoef) == 0) { |
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VCOPY(lr.rdir, nd.prdir); |
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rayvalue(&lr); |
267 |
< |
scalecolor(lr.rcol, nd.tspec); |
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< |
multcolor(lr.rcol, nd.mcolor); /* modified by color */ |
267 |
> |
multcolor(lr.rcol, lr.rcoef); |
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addcolor(r->rcol, lr.rcol); |
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transtest *= bright(lr.rcol); |
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transdist = r->rot + lr.rt; |
280 |
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if (nd.rspec > FTINY) { |
281 |
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nd.specfl |= SP_REFL; |
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/* compute specular color */ |
283 |
< |
if (m->otype == MAT_METAL) |
283 |
> |
if (m->otype != MAT_METAL) { |
284 |
> |
setcolor(nd.scolor, nd.rspec, nd.rspec, nd.rspec); |
285 |
> |
} else if (fest > FTINY) { |
286 |
> |
d = nd.rspec*(1. - fest); |
287 |
> |
for (i = 0; i < 3; i++) |
288 |
> |
nd.scolor[i] = fest + nd.mcolor[i]*d; |
289 |
> |
} else { |
290 |
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copycolor(nd.scolor, nd.mcolor); |
291 |
< |
else |
292 |
< |
setcolor(nd.scolor, 1.0, 1.0, 1.0); |
261 |
< |
scalecolor(nd.scolor, nd.rspec); |
291 |
> |
scalecolor(nd.scolor, nd.rspec); |
292 |
> |
} |
293 |
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/* check threshold */ |
294 |
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if (!(nd.specfl & SP_PURE) && specthresh >= nd.rspec-FTINY) |
295 |
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nd.specfl |= SP_RBLT; |
300 |
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if (hastexture && DOT(nd.vrefl, r->ron) <= FTINY) |
301 |
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for (i = 0; i < 3; i++) /* safety measure */ |
302 |
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nd.vrefl[i] = r->rdir[i] + 2.*r->rod*r->ron[i]; |
303 |
< |
|
304 |
< |
if (!(r->crtype & SHADOW) && nd.specfl & SP_PURE) { |
305 |
< |
RAY lr; |
306 |
< |
if (rayorigin(&lr, r, REFLECTED, nd.rspec) == 0) { |
307 |
< |
VCOPY(lr.rdir, nd.vrefl); |
308 |
< |
rayvalue(&lr); |
309 |
< |
multcolor(lr.rcol, nd.scolor); |
310 |
< |
addcolor(r->rcol, lr.rcol); |
311 |
< |
if (!hastexture && nd.specfl & SP_FLAT) { |
312 |
< |
mirtest = 2.*bright(lr.rcol); |
313 |
< |
mirdist = r->rot + lr.rt; |
314 |
< |
} |
303 |
> |
checknorm(nd.vrefl); |
304 |
> |
} |
305 |
> |
/* reflected ray */ |
306 |
> |
if ((nd.specfl&(SP_REFL|SP_PURE|SP_RBLT)) == (SP_REFL|SP_PURE)) { |
307 |
> |
RAY lr; |
308 |
> |
if (rayorigin(&lr, REFLECTED, r, nd.scolor) == 0) { |
309 |
> |
VCOPY(lr.rdir, nd.vrefl); |
310 |
> |
rayvalue(&lr); |
311 |
> |
multcolor(lr.rcol, lr.rcoef); |
312 |
> |
addcolor(r->rcol, lr.rcol); |
313 |
> |
if (!hastexture && nd.specfl & SP_FLAT) { |
314 |
> |
mirtest = 2.*bright(lr.rcol); |
315 |
> |
mirdist = r->rot + lr.rt; |
316 |
|
} |
317 |
|
} |
318 |
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} |
322 |
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if (nd.specfl & SP_PURE && nd.rdiff <= FTINY && nd.tdiff <= FTINY) |
323 |
|
return(1); /* 100% pure specular */ |
324 |
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|
325 |
< |
if (nd.specfl & (SP_REFL|SP_TRAN) && !(nd.specfl & SP_PURE)) |
326 |
< |
gaussamp(r, &nd); |
325 |
> |
if (!(nd.specfl & SP_PURE)) |
326 |
> |
gaussamp(r, &nd); /* checks *BLT flags */ |
327 |
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|
328 |
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if (nd.rdiff > FTINY) { /* ambient from this side */ |
329 |
< |
ambient(ctmp, r, hastexture?nd.pnorm:r->ron); |
329 |
> |
copycolor(ctmp, nd.mcolor); /* modified by material color */ |
330 |
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if (nd.specfl & SP_RBLT) |
331 |
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scalecolor(ctmp, 1.0-nd.trans); |
332 |
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else |
333 |
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scalecolor(ctmp, nd.rdiff); |
334 |
< |
multcolor(ctmp, nd.mcolor); /* modified by material color */ |
334 |
> |
multambient(ctmp, r, hastexture ? nd.pnorm : r->ron); |
335 |
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addcolor(r->rcol, ctmp); /* add to returned color */ |
336 |
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} |
337 |
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if (nd.tdiff > FTINY) { /* ambient from other side */ |
338 |
+ |
copycolor(ctmp, nd.mcolor); /* modified by color */ |
339 |
+ |
if (nd.specfl & SP_TBLT) |
340 |
+ |
scalecolor(ctmp, nd.trans); |
341 |
+ |
else |
342 |
+ |
scalecolor(ctmp, nd.tdiff); |
343 |
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flipsurface(r); |
344 |
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if (hastexture) { |
345 |
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FVECT bnorm; |
346 |
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bnorm[0] = -nd.pnorm[0]; |
347 |
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bnorm[1] = -nd.pnorm[1]; |
348 |
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bnorm[2] = -nd.pnorm[2]; |
349 |
< |
ambient(ctmp, r, bnorm); |
349 |
> |
multambient(ctmp, r, bnorm); |
350 |
|
} else |
351 |
< |
ambient(ctmp, r, r->ron); |
315 |
< |
if (nd.specfl & SP_TBLT) |
316 |
< |
scalecolor(ctmp, nd.trans); |
317 |
< |
else |
318 |
< |
scalecolor(ctmp, nd.tdiff); |
319 |
< |
multcolor(ctmp, nd.mcolor); /* modified by color */ |
351 |
> |
multambient(ctmp, r, r->ron); |
352 |
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addcolor(r->rcol, ctmp); |
353 |
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flipsurface(r); |
354 |
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} |
365 |
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} |
366 |
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|
367 |
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|
368 |
< |
static |
369 |
< |
gaussamp(r, np) /* sample gaussian specular */ |
370 |
< |
RAY *r; |
371 |
< |
register NORMDAT *np; |
368 |
> |
static void |
369 |
> |
gaussamp( /* sample Gaussian specular */ |
370 |
> |
RAY *r, |
371 |
> |
register NORMDAT *np |
372 |
> |
) |
373 |
|
{ |
374 |
|
RAY sr; |
375 |
|
FVECT u, v, h; |
392 |
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fcross(v, np->pnorm, u); |
393 |
|
/* compute reflection */ |
394 |
|
if ((np->specfl & (SP_REFL|SP_RBLT)) == SP_REFL && |
395 |
< |
rayorigin(&sr, r, SPECULAR, np->rspec) == 0) { |
395 |
> |
rayorigin(&sr, SPECULAR, r, np->scolor) == 0) { |
396 |
|
dimlist[ndims++] = (int)np->mp; |
397 |
|
for (niter = 0; niter < MAXITER; niter++) { |
398 |
|
if (niter) |
401 |
|
d = urand(ilhash(dimlist,ndims)+samplendx); |
402 |
|
multisamp(rv, 2, d); |
403 |
|
d = 2.0*PI * rv[0]; |
404 |
< |
cosp = cos(d); |
405 |
< |
sinp = sin(d); |
404 |
> |
cosp = tcos(d); |
405 |
> |
sinp = tsin(d); |
406 |
|
rv[1] = 1.0 - specjitter*rv[1]; |
407 |
|
if (rv[1] <= FTINY) |
408 |
|
d = 1.0; |
415 |
|
sr.rdir[i] = r->rdir[i] + d*h[i]; |
416 |
|
if (DOT(sr.rdir, r->ron) > FTINY) { |
417 |
|
rayvalue(&sr); |
418 |
< |
multcolor(sr.rcol, np->scolor); |
418 |
> |
multcolor(sr.rcol, sr.rcoef); |
419 |
|
addcolor(r->rcol, sr.rcol); |
420 |
|
break; |
421 |
|
} |
423 |
|
ndims--; |
424 |
|
} |
425 |
|
/* compute transmission */ |
426 |
+ |
copycolor(sr.rcoef, np->mcolor); /* modified by color */ |
427 |
+ |
scalecolor(sr.rcoef, np->tspec); |
428 |
|
if ((np->specfl & (SP_TRAN|SP_TBLT)) == SP_TRAN && |
429 |
< |
rayorigin(&sr, r, SPECULAR, np->tspec) == 0) { |
429 |
> |
rayorigin(&sr, SPECULAR, r, sr.rcoef) == 0) { |
430 |
|
dimlist[ndims++] = (int)np->mp; |
431 |
|
for (niter = 0; niter < MAXITER; niter++) { |
432 |
|
if (niter) |
435 |
|
d = urand(ilhash(dimlist,ndims)+1823+samplendx); |
436 |
|
multisamp(rv, 2, d); |
437 |
|
d = 2.0*PI * rv[0]; |
438 |
< |
cosp = cos(d); |
439 |
< |
sinp = sin(d); |
438 |
> |
cosp = tcos(d); |
439 |
> |
sinp = tsin(d); |
440 |
|
rv[1] = 1.0 - specjitter*rv[1]; |
441 |
|
if (rv[1] <= FTINY) |
442 |
|
d = 1.0; |
443 |
|
else |
444 |
< |
d = sqrt( -log(rv[1]) * np->alpha2 ); |
444 |
> |
d = sqrt( np->alpha2 * -log(rv[1]) ); |
445 |
|
for (i = 0; i < 3; i++) |
446 |
|
sr.rdir[i] = np->prdir[i] + d*(cosp*u[i] + sinp*v[i]); |
447 |
|
if (DOT(sr.rdir, r->ron) < -FTINY) { |
448 |
|
normalize(sr.rdir); /* OK, normalize */ |
449 |
|
rayvalue(&sr); |
450 |
< |
scalecolor(sr.rcol, np->tspec); |
416 |
< |
multcolor(sr.rcol, np->mcolor); /* modified */ |
450 |
> |
multcolor(sr.rcol, sr.rcoef); |
451 |
|
addcolor(r->rcol, sr.rcol); |
452 |
|
break; |
453 |
|
} |