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typedef struct { |
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OBJREC *mp; /* material pointer */ |
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RAY *rp; /* ray pointer */ |
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short specfl; /* specularity flags, defined above */ |
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COLOR mcolor; /* color of this material */ |
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COLOR scolor; /* color of specular component */ |
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double omega; /* light source size */ |
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{ |
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double ldot; |
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double dtmp; |
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int i; |
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double dtmp, d2; |
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FVECT vtmp; |
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COLOR ctmp; |
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setcolor(cval, 0.0, 0.0, 0.0); |
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* gaussian distribution model. |
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*/ |
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/* roughness */ |
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dtmp = 2.0*np->alpha2; |
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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/(2.0*PI); |
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dtmp += omega/(4.0*PI); |
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/* delta */ |
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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 = 2.0 - 2.0*d2/sqrt(DOT(vtmp,vtmp)); |
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/* gaussian */ |
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dtmp = exp((DOT(np->vrefl,ldir)-1.)/dtmp)/(2.*PI)/dtmp; |
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dtmp = exp(-d2/dtmp)/(4.*PI*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 / np->pdot; |
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dtmp *= omega * sqrt(ldot/np->pdot); |
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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->alpha2/2.0 + omega/(2.0*PI); |
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dtmp = np->alpha2/4.0 + omega/PI; |
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/* gaussian */ |
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< |
dtmp = exp((DOT(np->prdir,ldir)-1.)/dtmp)/(2.*PI)/dtmp; |
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> |
dtmp = exp((2.*DOT(np->prdir,ldir)-2.)/dtmp)/(4.*PI*dtmp); |
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/* worth using? */ |
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if (dtmp > FTINY) { |
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copycolor(ctmp, np->mcolor); |
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< |
dtmp *= np->tspec * omega / np->pdot; |
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> |
dtmp *= np->tspec * omega * sqrt(-ldot/np->pdot); |
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scalecolor(ctmp, dtmp); |
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addcolor(cval, ctmp); |
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} |
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if (m->oargs.nfargs != (m->otype == MAT_TRANS ? 7 : 5)) |
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objerror(m, USER, "bad number of arguments"); |
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nd.mp = m; |
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nd.rp = r; |
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/* get material color */ |
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setcolor(nd.mcolor, m->oargs.farg[0], |
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m->oargs.farg[1], |
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colval(nd.scolor,i) += (1.0-colval(nd.scolor,i))*dtmp; |
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nd.rspec += (1.0-nd.rspec)*dtmp; |
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/* check threshold */ |
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< |
if (specthresh > FTINY && |
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< |
((specthresh >= 1.-FTINY || |
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< |
specthresh + (.05 - .1*frandom()) > nd.rspec))) |
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> |
if (!(nd.specfl & SP_PURE) && |
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> |
specthresh > FTINY && |
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> |
(specthresh >= 1.-FTINY || |
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> |
specthresh + .05 - .1*frandom() > nd.rspec)) |
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nd.specfl |= SP_RBLT; |
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/* compute reflected ray */ |
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for (i = 0; i < 3; i++) |
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if (nd.tspec > FTINY) { |
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nd.specfl |= SP_TRAN; |
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/* check threshold */ |
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< |
if (specthresh > FTINY && |
| 234 |
< |
((specthresh >= 1.-FTINY || |
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< |
specthresh + |
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< |
(.05 - .1*frandom()) > nd.tspec))) |
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> |
if (!(nd.specfl & SP_PURE) && specthresh > FTINY && |
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> |
(specthresh >= 1.-FTINY || |
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> |
specthresh + .05 - .1*frandom() > nd.tspec)) |
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nd.specfl |= SP_TBLT; |
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if (r->crtype & SHADOW || |
| 238 |
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DOT(r->pert,r->pert) <= FTINY*FTINY) { |
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double rv[2]; |
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double d, sinp, cosp; |
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register int i; |
| 321 |
+ |
/* quick test */ |
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if ((np->specfl & (SP_REFL|SP_RBLT)) != SP_REFL && |
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(np->specfl & (SP_TRAN|SP_TBLT)) != SP_TRAN) |
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return; |
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/* set up sample coordinates */ |
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v[0] = v[1] = v[2] = 0.0; |
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for (i = 0; i < 3; i++) |
