| 38 |
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|
| 39 |
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typedef struct { |
| 40 |
|
OBJREC *mp; /* material pointer */ |
| 41 |
– |
RAY *pr; /* intersected ray */ |
| 41 |
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COLOR mcolor; /* color of this material */ |
| 42 |
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COLOR scolor; /* color of specular component */ |
| 43 |
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FVECT vrefl; /* vector in direction of reflected ray */ |
| 44 |
+ |
FVECT prdir; /* vector in transmitted direction */ |
| 45 |
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double alpha2; /* roughness squared times 2 */ |
| 46 |
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double rdiff, rspec; /* reflected specular, diffuse */ |
| 47 |
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double trans; /* transmissivity */ |
| 91 |
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/* worth using? */ |
| 92 |
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if (dtmp > FTINY) { |
| 93 |
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copycolor(ctmp, np->scolor); |
| 94 |
< |
dtmp *= omega; |
| 94 |
> |
dtmp *= omega / np->pdot; |
| 95 |
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scalecolor(ctmp, dtmp); |
| 96 |
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addcolor(cval, ctmp); |
| 97 |
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} |
| 108 |
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if (ldot < -FTINY && np->tspec > FTINY && np->alpha2 > FTINY) { |
| 109 |
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/* |
| 110 |
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* Compute specular transmission. Specular transmission |
| 111 |
< |
* is unaffected by material color. |
| 111 |
> |
* is always modified by material color. |
| 112 |
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*/ |
| 113 |
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/* roughness + source */ |
| 114 |
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dtmp = np->alpha2 + omega/(2.0*PI); |
| 115 |
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/* gaussian */ |
| 116 |
< |
dtmp = exp((DOT(np->pr->rdir,ldir)-1.)/dtmp)/(2.*PI)/dtmp; |
| 116 |
> |
dtmp = exp((DOT(np->prdir,ldir)-1.)/dtmp)/(2.*PI)/dtmp; |
| 117 |
|
/* worth using? */ |
| 118 |
|
if (dtmp > FTINY) { |
| 119 |
< |
dtmp *= np->tspec * omega; |
| 120 |
< |
setcolor(ctmp, dtmp, dtmp, dtmp); |
| 119 |
> |
copycolor(ctmp, np->mcolor); |
| 120 |
> |
dtmp *= np->tspec * omega / np->pdot; |
| 121 |
> |
scalecolor(ctmp, dtmp); |
| 122 |
|
addcolor(cval, ctmp); |
| 123 |
|
} |
| 124 |
|
} |
| 141 |
|
if (r->crtype & SHADOW && m->otype != MAT_TRANS) |
| 142 |
|
return; |
| 143 |
|
nd.mp = m; |
| 143 |
– |
nd.pr = r; |
| 144 |
|
/* get material color */ |
| 145 |
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setcolor(nd.mcolor, m->oargs.farg[0], |
| 146 |
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m->oargs.farg[1], |
| 154 |
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/* get modifiers */ |
| 155 |
|
raytexture(r, m->omod); |
| 156 |
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nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */ |
| 157 |
+ |
if (nd.pdot < .001) |
| 158 |
+ |
nd.pdot = .001; /* non-zero for dirnorm() */ |
| 159 |
|
multcolor(nd.mcolor, r->pcol); /* modify material color */ |
| 160 |
|
transtest = 0; |
| 161 |
|
/* get specular component */ |
| 192 |
|
nd.trans = m->oargs.farg[5]*(1.0 - nd.rspec); |
| 193 |
|
nd.tspec = nd.trans * m->oargs.farg[6]; |
| 194 |
|
nd.tdiff = nd.trans - nd.tspec; |
| 195 |
+ |
if (r->crtype & SHADOW || DOT(r->pert,r->pert) <= FTINY*FTINY) { |
| 196 |
+ |
VCOPY(nd.prdir, r->rdir); |
| 197 |
+ |
transtest = 2; |
| 198 |
+ |
} else { |
| 199 |
+ |
for (i = 0; i < 3; i++) /* perturb direction */ |
| 200 |
+ |
nd.prdir[i] = r->rdir[i] - .75*r->pert[i]; |
| 201 |
+ |
normalize(nd.prdir); |
| 202 |
+ |
} |
| 203 |
|
} else |
| 204 |
|
nd.tdiff = nd.tspec = nd.trans = 0.0; |
| 205 |
|
/* transmitted ray */ |
| 206 |
|
if (nd.tspec > FTINY && nd.alpha2 <= FTINY) { |
| 207 |
|
RAY lr; |
| 208 |
|
if (rayorigin(&lr, r, TRANS, nd.tspec) == 0) { |
| 209 |
< |
if (!(r->crtype & SHADOW) && |
| 200 |
< |
DOT(r->pert,r->pert) > FTINY*FTINY) { |
| 201 |
< |
for (i = 0; i < 3; i++) /* perturb direction */ |
| 202 |
< |
lr.rdir[i] = r->rdir[i] - |
| 203 |
< |
.75*r->pert[i]; |
| 204 |
< |
normalize(lr.rdir); |
| 205 |
< |
} else { |
| 206 |
< |
VCOPY(lr.rdir, r->rdir); |
| 207 |
< |
transtest = 2; |
| 208 |
< |
} |
| 209 |
> |
VCOPY(lr.rdir, nd.prdir); |
| 210 |
|
rayvalue(&lr); |
| 211 |
|
scalecolor(lr.rcol, nd.tspec); |
| 212 |
|
multcolor(lr.rcol, nd.mcolor); /* modified by color */ |
| 239 |
|
scalecolor(ctmp, nd.tdiff); |
| 240 |
|
else |
| 241 |
|
scalecolor(ctmp, nd.trans); |
| 242 |
< |
multcolor(ctmp, nd.mcolor); |
| 242 |
> |
multcolor(ctmp, nd.mcolor); /* modified by color */ |
| 243 |
|
addcolor(r->rcol, ctmp); |
| 244 |
|
flipsurface(r); |
| 245 |
|
} |
