| 60 |
|
{ |
| 61 |
|
double cos_thresh; |
| 62 |
|
int ii, jj; |
| 63 |
< |
/* min. spacing = 1/10th division */ |
| 64 |
< |
cos_thresh = (PI/10.)/(double)hp->ns; |
| 63 |
> |
/* min. spacing = 1/4th division */ |
| 64 |
> |
cos_thresh = (PI/4.)/(double)hp->ns; |
| 65 |
|
cos_thresh = 1. - .5*cos_thresh*cos_thresh; |
| 66 |
|
/* check existing neighbors */ |
| 67 |
|
for (ii = i-1; ii <= i+1; ii++) { |
| 126 |
|
/* avoid coincident samples */ |
| 127 |
|
if (!n && ambcollision(hp, i, j, ar.rdir)) { |
| 128 |
|
spt[0] = frandom(); spt[1] = frandom(); |
| 129 |
< |
goto resample; |
| 129 |
> |
goto resample; /* reject this sample */ |
| 130 |
|
} |
| 131 |
|
dimlist[ndims++] = AI(hp,i,j) + 90171; |
| 132 |
|
rayvalue(&ar); /* evaluate ray */ |
| 137 |
|
if (ar.rt*ap->d < 1.0) /* new/closer distance? */ |
| 138 |
|
ap->d = 1.0/ar.rt; |
| 139 |
|
if (!n) { /* record first vertex & value */ |
| 140 |
< |
if (ar.rt > 10.0*thescene.cusize) |
| 141 |
< |
ar.rt = 10.0*thescene.cusize; |
| 140 |
> |
if (ar.rt > 10.0*thescene.cusize + 1000.) |
| 141 |
> |
ar.rt = 10.0*thescene.cusize + 1000.; |
| 142 |
|
VSUM(ap->p, ar.rorg, ar.rdir, ar.rt); |
| 143 |
|
copycolor(ap->v, ar.rcol); |
| 144 |
|
} else { /* else update recorded value */ |
| 156 |
|
} |
| 157 |
|
|
| 158 |
|
|
| 159 |
< |
/* Estimate errors based on ambient division differences */ |
| 159 |
> |
/* Estimate variance based on relative ambient division differences */ |
| 160 |
|
static float * |
| 161 |
|
getambdiffs(AMBHEMI *hp) |
| 162 |
|
{ |
| 163 |
+ |
const double normf = 1./bright(hp->acoef); |
| 164 |
|
float *earr = (float *)calloc(hp->ns*hp->ns, sizeof(float)); |
| 165 |
|
float *ep; |
| 166 |
|
AMBSAMP *ap; |
| 167 |
< |
double b, d2; |
| 167 |
> |
double b, b1, d2; |
| 168 |
|
int i, j; |
| 169 |
|
|
| 170 |
|
if (earr == NULL) /* out of memory? */ |
| 171 |
|
return(NULL); |
| 172 |
< |
/* compute squared neighbor diffs */ |
| 172 |
> |
/* sum squared neighbor diffs */ |
| 173 |
|
for (ap = hp->sa, ep = earr, i = 0; i < hp->ns; i++) |
| 174 |
|
for (j = 0; j < hp->ns; j++, ap++, ep++) { |
| 175 |
|
b = bright(ap[0].v); |
| 176 |
|
if (i) { /* from above */ |
| 177 |
< |
d2 = b - bright(ap[-hp->ns].v); |
| 178 |
< |
d2 *= d2; |
| 177 |
> |
b1 = bright(ap[-hp->ns].v); |
| 178 |
> |
d2 = (b - b1)/(b + b1); |
| 179 |
> |
d2 *= d2*normf; |
| 180 |
|
ep[0] += d2; |
| 181 |
|
ep[-hp->ns] += d2; |
| 182 |
|
} |
| 183 |
|
if (!j) continue; |
| 184 |
|
/* from behind */ |
| 185 |
< |
d2 = b - bright(ap[-1].v); |
| 186 |
< |
d2 *= d2; |
| 185 |
> |
b1 = bright(ap[-1].v); |
| 186 |
> |
d2 = (b - b1)/(b + b1); |
| 187 |
> |
d2 *= d2*normf; |
| 188 |
|
ep[0] += d2; |
| 189 |
|
ep[-1] += d2; |
| 190 |
|
if (!i) continue; |
| 191 |
|
/* diagonal */ |
| 192 |
< |
d2 = b - bright(ap[-hp->ns-1].v); |
| 193 |
< |
d2 *= d2; |
| 192 |
> |
b1 = bright(ap[-hp->ns-1].v); |
| 193 |
> |
d2 = (b - b1)/(b + b1); |
| 194 |
> |
d2 *= d2*normf; |
| 195 |
|
ep[0] += d2; |
| 196 |
|
ep[-hp->ns-1] += d2; |
| 197 |
|
} |
| 218 |
|
{ |
| 219 |
|
float *earr = getambdiffs(hp); |
| 220 |
|
double e2rem = 0; |
| 217 |
– |
AMBSAMP *ap; |
| 221 |
|
float *ep; |
| 222 |
|
int i, j, n, nss; |
| 223 |
|
|
| 227 |
|
for (ep = earr + hp->ns*hp->ns; ep > earr; ) |
| 228 |
|
e2rem += *--ep; |
| 229 |
|
ep = earr; /* perform super-sampling */ |
| 230 |
< |
for (ap = hp->sa, i = 0; i < hp->ns; i++) |
| 231 |
< |
for (j = 0; j < hp->ns; j++, ap++) { |
| 230 |
> |
for (i = 0; i < hp->ns; i++) |
| 231 |
> |
for (j = 0; j < hp->ns; j++) { |
| 232 |
|
if (e2rem <= FTINY) |
| 233 |
|
goto done; /* nothing left to do */ |
| 234 |
|
nss = *ep/e2rem*cnt + frandom(); |
| 235 |
|
for (n = 1; n <= nss && ambsample(hp,i,j,n); n++) |
| 236 |
< |
--cnt; |
| 236 |
> |
if (!--cnt) goto done; |
| 237 |
|
e2rem -= *ep++; /* update remainder */ |
| 238 |
|
} |
| 239 |
|
done: |
| 251 |
|
AMBHEMI *hp; |
| 252 |
|
double d; |
| 253 |
|
int n, i, j; |
| 254 |
+ |
/* insignificance check */ |
| 255 |
+ |
if (bright(rcol) <= FTINY) |
| 256 |
+ |
return(NULL); |
| 257 |
|
/* set number of divisions */ |
| 258 |
|
if (ambacc <= FTINY && |
| 259 |
|
wt > (d = 0.8*intens(rcol)*r->rweight/(ambdiv*minweight))) |
| 676 |
|
for (a1 = ang-ang_res; a1 <= ang+ang_res; a1 += ang_step) |
| 677 |
|
flgs |= 1L<<(int)(16/PI*(a1 + 2.*PI*(a1 < 0))); |
| 678 |
|
} |
| 673 |
– |
/* add low-angle incident (< 20deg) */ |
| 674 |
– |
if (fabs(hp->rp->rod) <= 0.342) { |
| 675 |
– |
u = -DOT(hp->rp->rdir, uv[0]); |
| 676 |
– |
v = -DOT(hp->rp->rdir, uv[1]); |
| 677 |
– |
if ((r0*r0*u*u + r1*r1*v*v) > hp->rp->rot*hp->rp->rot) { |
| 678 |
– |
ang = atan2a(v, u); |
| 679 |
– |
ang += 2.*PI*(ang < 0); |
| 680 |
– |
ang *= 16/PI; |
| 681 |
– |
if ((ang < .5) | (ang >= 31.5)) |
| 682 |
– |
flgs |= 0x80000001; |
| 683 |
– |
else |
| 684 |
– |
flgs |= 3L<<(int)(ang-.5); |
| 685 |
– |
} |
| 686 |
– |
} |
| 679 |
|
return(flgs); |
| 680 |
|
} |
| 681 |
|
|
