| 11 |
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#include "rterror.h" |
| 12 |
|
#include "platform.h" |
| 13 |
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#include <stdlib.h> |
| 14 |
+ |
#include <math.h> |
| 15 |
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|
| 16 |
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float *datarr; /* our loaded BSDF data array */ |
| 17 |
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int ttrank = 4; /* tensor tree rank */ |
| 18 |
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int log2g = 4; /* log2 of grid resolution */ |
| 19 |
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int infmt = 'a'; /* input format ('a','f','d') */ |
| 20 |
< |
double tthresh = .05; /* relative acceptance threshold */ |
| 20 |
> |
double pctcull = 95.; /* target culling percentile */ |
| 21 |
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|
| 22 |
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#define dval3(ix,ox,oy) datarr[((((ix)<<log2g)+(ox))<<log2g)+(oy)] |
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#define dval4(ix,iy,ox,oy) datarr[((((((ix)<<log2g)+(iy))<<log2g)+(ox))<<log2g)+(oy)] |
| 24 |
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|
| 24 |
– |
#define above_threshold(tp) ((tp)->vmax - (tp)->vmin > 2.*tthresh*(tp)->vavg) |
| 25 |
– |
|
| 25 |
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/* Tensor tree node */ |
| 26 |
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typedef struct ttree_s { |
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float vmin, vmax; /* value extrema */ |
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struct ttree_s *kid; /* 2^ttrank children */ |
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} TNODE; |
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|
| 32 |
+ |
#define HISTLEN 300 /* histogram resolution */ |
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#define HISTMAX 10. /* maximum recorded measure in histogram */ |
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|
| 35 |
+ |
int histo[HISTLEN]; /* histogram freq. of variance measure */ |
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+ |
|
| 37 |
+ |
double tthresh; /* acceptance threshold (TBD) */ |
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|
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+ |
#define var_measure(tp) ( ((tp)->vmax - (tp)->vmin) / \ |
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+ |
(sqrt((tp)->vavg) + .03) ) |
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#define above_threshold(tp) (var_measure(tp) > tthresh) |
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|
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/* Allocate a new set of children for the given node (no checks) */ |
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static void |
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new_kids(TNODE *pn) |
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tp->vavg += val; |
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} |
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tp->vavg /= (float)(1<<ttrank); |
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/* record stats */ |
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i = (HISTLEN/HISTMAX) * var_measure(tp); |
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if (i >= HISTLEN) i = HISTLEN-1; |
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++histo[i]; |
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return; |
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} |
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--l2s; /* else still branching */ |
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tp->vavg += tp->kid[i].vavg; |
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} |
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tp->vavg /= (float)(1<<ttrank); |
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– |
/* is variation above threshold? */ |
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– |
if (!above_threshold(tp)) |
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– |
free_kids(tp); /* if not, trim branches */ |
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} |
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|
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/* Set our trimming threshold */ |
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static void |
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set_threshold(void) |
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{ |
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int hsum = 0; |
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int i; |
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|
| 118 |
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for (i = HISTLEN; i--; ) |
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hsum += histo[i]; |
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hsum = pctcull*.01 * (double)hsum; |
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for (i = 0; hsum > 0; i++) |
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hsum -= histo[i]; |
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tthresh = (HISTMAX/HISTLEN) * i; |
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} |
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|
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/* Trim our tree according to the current threshold */ |
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static void |
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trim_tree(TNODE *tp) |
| 129 |
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{ |
| 130 |
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if (tp->kid == NULL) |
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return; |
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if (above_threshold(tp)) { /* keeping branches? */ |
| 133 |
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int i = 1<<ttrank; |
| 134 |
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while (i--) |
| 135 |
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trim_tree(tp->kid+i); |
| 136 |
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return; |
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} |
| 138 |
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free_kids(tp); /* else trim at this point */ |
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} |
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|
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/* Print a tensor tree from the given hypercube */ |
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static void |
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print_tree(const TNODE *tp, const int bmin[], int l2s) |
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for (i = 0; i < 1<<ttrank; i++) { |
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float val; |
| 154 |
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for (j = ttrank; j--; ) |
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< |
bkmin[j] = bmin[j] + (i>>j & 1); |
| 155 |
> |
bkmin[j] = bmin[j] + (i>>(ttrank-1-j) & 1); |
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val = (ttrank == 3) ? dval3(bkmin[0],bkmin[1],bkmin[2]) |
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: dval4(bkmin[0],bkmin[1],bkmin[2],bkmin[3]); |
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printf(" %.4e", val); |
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return(nread); |
| 236 |
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} |
| 237 |
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|
| 238 |
+ |
/* Truncate any negative values to zero */ |
| 239 |
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static void |
| 240 |
+ |
noneg(float *varr, int n) |
| 241 |
+ |
{ |
| 242 |
+ |
int nnan = 0; |
| 243 |
+ |
|
| 244 |
+ |
while (n-- > 0) { |
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+ |
#ifdef isnan |
| 246 |
+ |
if (isnan(*varr)) { |
| 247 |
+ |
*varr = 0; |
| 248 |
+ |
++nnan; |
| 249 |
+ |
} else |
| 250 |
+ |
#endif |
| 251 |
+ |
if (*varr < 0) *varr = 0; |
| 252 |
+ |
++varr; |
| 253 |
+ |
} |
| 254 |
+ |
if (nnan) |
| 255 |
+ |
fprintf(stderr, "Warning: BSDF data contains %d NaN values\n", |
| 256 |
+ |
nnan); |
| 257 |
+ |
} |
| 258 |
+ |
|
| 259 |
|
/* Load data array, filling zeroes for rank 3 demi-tensor */ |
| 260 |
|
static void |
| 261 |
< |
load_data() |
| 261 |
> |
load_data(void) |
| 262 |
|
{ |
| 263 |
|
int (*readf)(float *, int) = NULL; |
| 264 |
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|
| 281 |
|
error(SYSTEM, "out of memory in load_data"); |
| 282 |
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if (ttrank == 3) { |
| 283 |
|
int ix, ox; |
| 284 |
< |
for (ix = 0; ix < 1<<log2g; ix++) |
| 284 |
> |
for (ix = 0; ix < 1<<(log2g-1); ix++) |
| 285 |
|
for (ox = 0; ox < 1<<log2g; ox++) |
| 286 |
< |
(*readf)(datarr+((((ix)<<log2g)+(ox))<<log2g), |
| 287 |
< |
1<<(log2g-1)); |
| 286 |
> |
(*readf)(datarr+(((ix<<log2g)+ox)<<log2g), |
| 287 |
> |
1<<log2g); |
| 288 |
|
} else /* ttrank == 4 */ { |
| 289 |
|
int ix, iy, ox; |
| 290 |
|
for (ix = 0; ix < 1<<log2g; ix++) |
| 291 |
|
for (iy = 0; iy < 1<<log2g; iy++) |
| 292 |
|
for (ox = 0; ox < 1<<log2g; ox++) |
| 293 |
|
(*readf)(datarr + |
| 294 |
< |
((((((ix)<<log2g)+(iy))<<log2g)+(ox))<<log2g), |
| 294 |
> |
(((((ix<<log2g)+iy)<<log2g)+ox)<<log2g), |
| 295 |
|
1<<log2g); |
| 296 |
|
} |
| 297 |
|
(*readf)(NULL, 0); /* releases any buffers */ |
| 310 |
|
} |
| 311 |
|
} else if (getc(stdin) != EOF) |
| 312 |
|
error(WARNING, "binary data past end of expected input"); |
| 313 |
+ |
|
| 314 |
+ |
noneg(datarr, 1<<(log2g*ttrank)); /* take precautions */ |
| 315 |
|
} |
| 316 |
|
|
| 317 |
+ |
/* Enforce reciprocity by averaging data values */ |
| 318 |
+ |
static void |
| 319 |
+ |
do_reciprocity(void) |
| 320 |
+ |
{ |
| 321 |
+ |
const int siz = 1<<log2g; |
| 322 |
+ |
float *v1p, *v2p; |
| 323 |
+ |
|
| 324 |
+ |
if (ttrank == 3) { |
| 325 |
+ |
int ix, ox, oy; |
| 326 |
+ |
for (ix = 0; ix < siz>>1; ix++) |
| 327 |
+ |
for (ox = 0; ox < siz; ox++) |
| 328 |
+ |
for (oy = 0; oy < siz>>1; oy++) { |
| 329 |
+ |
v1p = &dval3(ix,ox,oy); |
| 330 |
+ |
v2p = &dval3(ix,ox,siz-1-oy); |
| 331 |
+ |
*v1p = *v2p = .5f*( *v1p + *v2p ); |
| 332 |
+ |
} |
| 333 |
+ |
} else /* ttrank == 4 */ { |
| 334 |
+ |
int ix, iy, ox, oy; |
| 335 |
+ |
for (ix = 1; ix < siz; ix++) |
| 336 |
+ |
for (iy = 1; iy < siz; iy++) |
| 337 |
+ |
for (ox = 0; ox < ix; ox++) |
| 338 |
+ |
for (oy = 0; oy < iy; oy++) { |
| 339 |
+ |
v1p = &dval4(siz-1-ix,siz-1-iy,ox,oy); |
| 340 |
+ |
v2p = &dval4(siz-1-ox,siz-1-oy,ix,iy); |
| 341 |
+ |
*v1p = *v2p = .5f*( *v1p + *v2p ); |
| 342 |
+ |
} |
| 343 |
+ |
} |
| 344 |
+ |
} |
| 345 |
+ |
|
| 346 |
|
/* Load BSDF array, coalesce uniform regions and format as tensor tree */ |
| 347 |
|
int |
| 348 |
|
main(int argc, char *argv[]) |
| 349 |
|
{ |
| 350 |
|
int doheader = 1; |
| 351 |
+ |
int recipavg = 0; |
| 352 |
|
int bmin[4]; |
| 353 |
|
TNODE gtree; |
| 354 |
|
int i; |
| 355 |
|
/* get options and parameters */ |
| 356 |
|
for (i = 1; i < argc && argv[i][0] == '-'; i++) |
| 357 |
|
switch (argv[i][1]) { |
| 358 |
+ |
case 'a': |
| 359 |
+ |
recipavg = !recipavg; |
| 360 |
+ |
break; |
| 361 |
|
case 'h': |
| 362 |
|
doheader = !doheader; |
| 363 |
|
break; |
| 372 |
|
goto userr; |
| 373 |
|
break; |
| 374 |
|
case 't': |
| 375 |
< |
tthresh = atof(argv[++i]); |
| 376 |
< |
if (tthresh <= 0) |
| 375 |
> |
pctcull = atof(argv[++i]); |
| 376 |
> |
if ((pctcull < 0) | (pctcull >= 100.)) |
| 377 |
|
goto userr; |
| 378 |
|
break; |
| 379 |
|
case 'f': |
| 387 |
|
if (i < argc-1) |
| 388 |
|
goto userr; |
| 389 |
|
/* load input data */ |
| 390 |
< |
if (i == argc-1 && freopen(argv[i], "rb", stdin) == NULL) { |
| 390 |
> |
if (i == argc-1 && freopen(argv[i], "r", stdin) == NULL) { |
| 391 |
|
sprintf(errmsg, "cannot open input file '%s'", argv[i]); |
| 392 |
|
error(SYSTEM, errmsg); |
| 393 |
|
} |
| 394 |
|
if (infmt != 'a') |
| 395 |
|
SET_FILE_BINARY(stdin); |
| 396 |
+ |
#ifdef getc_unlocked /* avoid lock/unlock overhead */ |
| 397 |
+ |
flockfile(stdin); |
| 398 |
+ |
#endif |
| 399 |
|
load_data(); |
| 400 |
+ |
if (recipavg) |
| 401 |
+ |
do_reciprocity(); |
| 402 |
|
if (doheader) { |
| 403 |
|
for (i = 0; i < argc; i++) { |
| 404 |
|
fputs(argv[i], stdout); |
| 409 |
|
gtree.kid = NULL; /* create our tree */ |
| 410 |
|
bmin[0] = bmin[1] = bmin[2] = bmin[3] = 0; |
| 411 |
|
build_tree(>ree, bmin, log2g); |
| 412 |
+ |
/* compute threshold & trim tree */ |
| 413 |
+ |
set_threshold(); |
| 414 |
+ |
trim_tree(>ree); |
| 415 |
|
/* format to stdout */ |
| 416 |
|
print_tree(>ree, bmin, log2g); |
| 417 |
|
/* Clean up isn't necessary for main()... |
| 420 |
|
*/ |
| 421 |
|
return(0); |
| 422 |
|
userr: |
| 423 |
< |
fprintf(stderr, "Usage: %s [-h][-f{a|f|d}][-r {3|4}][-g log2grid][-t thresh] [input]\n", |
| 423 |
> |
fprintf(stderr, "Usage: %s [-h][-a][-f{a|f|d}][-r {3|4}][-g log2grid][-t trim%%] [input]\n", |
| 424 |
|
argv[0]); |
| 425 |
|
return(1); |
| 426 |
|
} |