| 20 |
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#include "random.h" |
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| 22 |
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| 23 |
– |
#define DISKTFRAC 0.25 /* disk area pretest fraction */ |
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double getdisk(); |
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| 25 |
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static OBJECT *vobject; /* virtual source objects */ |
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FVECT onorm; |
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FVECT offsdir; |
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double or, d; |
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+ |
int infront; |
| 237 |
+ |
int ssn; |
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int nok, nhit; |
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register int i, n; |
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/* return if pretesting disabled */ |
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/* get surface normal */ |
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(*sfun[o->otype].of->getpleq)(onorm, o); |
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/* set number of rays to sample */ |
| 246 |
< |
if (source[sn].sflags & SDISTANT) |
| 246 |
> |
if (source[sn].sflags & SDISTANT) { |
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n = (2./3.*PI*PI)*or2/(thescene.cusize*thescene.cusize)* |
| 248 |
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vspretest + .5; |
| 249 |
< |
else |
| 249 |
> |
infront = DOT(onorm, source[sn].sloc) > 0.; |
| 250 |
> |
} else { |
| 251 |
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n = or2/dist2(oc,source[sn].sloc)*vspretest + .5; |
| 252 |
+ |
for (i = 0; i < 3; i++) |
| 253 |
+ |
offsdir[i] = source[sn].sloc[i] - oc[i]; |
| 254 |
+ |
infront = DOT(onorm, offsdir) > 0.; |
| 255 |
+ |
} |
| 256 |
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if (n < 1) n = 1; |
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– |
/* limit tests to central region */ |
| 253 |
– |
or = DISKTFRAC*sqrt(or2); |
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/* sample */ |
| 258 |
+ |
or = sqrt(or2); |
| 259 |
+ |
ssn = 7*n; |
| 260 |
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nhit = nok = 0; |
| 261 |
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while (n-- > 0) { |
| 262 |
< |
samplendx++; |
| 263 |
< |
/* |
| 264 |
< |
* We're being real sloppy with our sample locations here. |
| 265 |
< |
*/ |
| 266 |
< |
for (i = 0; i < 3; i++) |
| 267 |
< |
offsdir[i] = or*(1. - 2.*urand(931*i+5821+n)); |
| 268 |
< |
d = DOT(offsdir,onorm); |
| 269 |
< |
for (i = 0; i < 3; i++) |
| 270 |
< |
sr.rorg[i] = oc[i] + (1.-d)*offsdir[i]; |
| 262 |
> |
/* get sample point */ |
| 263 |
> |
do { |
| 264 |
> |
if (--ssn < 0) |
| 265 |
> |
return(f); /* too small a target! */ |
| 266 |
> |
for (i = 0; i < 3; i++) |
| 267 |
> |
offsdir[i] = or*(1. - |
| 268 |
> |
2.*urand(931*i+5827+ssn)); |
| 269 |
> |
for (i = 0; i < 3; i++) |
| 270 |
> |
sr.rorg[i] = oc[i] + offsdir[i]; |
| 271 |
> |
d = DOT(offsdir,onorm); |
| 272 |
> |
if (infront) |
| 273 |
> |
for (i = 0; i < 3; i++) { |
| 274 |
> |
sr.rorg[i] -= (d-.0001)*onorm[i]; |
| 275 |
> |
sr.rdir[i] = -onorm[i]; |
| 276 |
> |
} |
| 277 |
> |
else |
| 278 |
> |
for (i = 0; i < 3; i++) { |
| 279 |
> |
sr.rorg[i] -= (d+.0001)*onorm[i]; |
| 280 |
> |
sr.rdir[i] = onorm[i]; |
| 281 |
> |
} |
| 282 |
> |
rayorigin(&sr, NULL, PRIMARY, 1.0); |
| 283 |
> |
} while (!(*ofun[o->otype].funp)(o, &sr)); |
| 284 |
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/* check against source */ |
| 285 |
+ |
samplendx++; |
| 286 |
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if (srcray(&sr, NULL, sn) == 0.0) |
| 287 |
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continue; |
| 288 |
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sr.revf = srcvalue; |
