1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: mkillum4.c,v 2.18 2009/06/06 05:03:47 greg Exp $"; |
3 |
#endif |
4 |
/* |
5 |
* Routines for handling BSDF data within mkillum |
6 |
*/ |
7 |
|
8 |
#include "mkillum.h" |
9 |
#include "paths.h" |
10 |
#include "ezxml.h" |
11 |
#include <ctype.h> |
12 |
|
13 |
#ifndef NBSDFSAMPS |
14 |
#define NBSDFSAMPS 32 /* BSDF resampling count */ |
15 |
#endif |
16 |
#define MAXLATS 46 /* maximum number of latitudes */ |
17 |
|
18 |
/* BSDF angle specification */ |
19 |
typedef struct { |
20 |
char name[64]; /* basis name */ |
21 |
int nangles; /* total number of directions */ |
22 |
struct { |
23 |
float tmin; /* starting theta */ |
24 |
short nphis; /* number of phis (0 term) */ |
25 |
} lat[MAXLATS+1]; /* latitudes */ |
26 |
} ANGLE_BASIS; |
27 |
|
28 |
#define MAXABASES 3 /* limit on defined bases */ |
29 |
|
30 |
static ANGLE_BASIS abase_list[MAXABASES] = { |
31 |
{ |
32 |
"LBNL/Klems Full", 145, |
33 |
{ {-5., 1}, |
34 |
{5., 8}, |
35 |
{15., 16}, |
36 |
{25., 20}, |
37 |
{35., 24}, |
38 |
{45., 24}, |
39 |
{55., 24}, |
40 |
{65., 16}, |
41 |
{75., 12}, |
42 |
{90., 0} } |
43 |
}, { |
44 |
"LBNL/Klems Half", 73, |
45 |
{ {-6.5, 1}, |
46 |
{6.5, 8}, |
47 |
{19.5, 12}, |
48 |
{32.5, 16}, |
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{46.5, 20}, |
50 |
{61.5, 12}, |
51 |
{76.5, 4}, |
52 |
{90., 0} } |
53 |
}, { |
54 |
"LBNL/Klems Quarter", 41, |
55 |
{ {-9., 1}, |
56 |
{9., 8}, |
57 |
{27., 12}, |
58 |
{46., 12}, |
59 |
{66., 8}, |
60 |
{90., 0} } |
61 |
} |
62 |
}; |
63 |
|
64 |
static int nabases = 3; /* current number of defined bases */ |
65 |
|
66 |
|
67 |
static int |
68 |
ab_getvec( /* get vector for this angle basis index */ |
69 |
FVECT v, |
70 |
int ndx, |
71 |
void *p |
72 |
) |
73 |
{ |
74 |
ANGLE_BASIS *ab = (ANGLE_BASIS *)p; |
75 |
int li; |
76 |
double alt, azi, d; |
77 |
|
78 |
if ((ndx < 0) | (ndx >= ab->nangles)) |
79 |
return(0); |
80 |
for (li = 0; ndx >= ab->lat[li].nphis; li++) |
81 |
ndx -= ab->lat[li].nphis; |
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alt = PI/180.*0.5*(ab->lat[li].tmin + ab->lat[li+1].tmin); |
83 |
azi = 2.*PI*ndx/ab->lat[li].nphis; |
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v[2] = d = cos(alt); |
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d = sqrt(1. - d*d); /* sin(alt) */ |
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v[0] = cos(azi)*d; |
87 |
v[1] = sin(azi)*d; |
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return(1); |
89 |
} |
90 |
|
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|
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static int |
93 |
ab_getndx( /* get index corresponding to the given vector */ |
94 |
FVECT v, |
95 |
void *p |
96 |
) |
97 |
{ |
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ANGLE_BASIS *ab = (ANGLE_BASIS *)p; |
99 |
int li, ndx; |
100 |
double alt, azi, d; |
101 |
|
102 |
if ((v[2] < -1.0) | (v[2] > 1.0)) |
103 |
return(-1); |
104 |
alt = 180.0/PI*acos(v[2]); |
105 |
azi = 180.0/PI*atan2(v[1], v[0]); |
106 |
if (azi < 0.0) azi += 360.0; |
107 |
for (li = 1; ab->lat[li].tmin <= alt; li++) |
108 |
if (!ab->lat[li].nphis) |
109 |
return(-1); |
110 |
--li; |
111 |
ndx = (int)((1./360.)*azi*ab->lat[li].nphis + 0.5); |
112 |
if (ndx >= ab->lat[li].nphis) ndx = 0; |
113 |
while (li--) |
114 |
ndx += ab->lat[li].nphis; |
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return(ndx); |
116 |
} |
117 |
|
118 |
|
119 |
static double |
120 |
ab_getohm( /* get solid angle for this angle basis index */ |
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int ndx, |
122 |
void *p |
123 |
) |
124 |
{ |
125 |
ANGLE_BASIS *ab = (ANGLE_BASIS *)p; |
126 |
int li; |
127 |
double theta, theta1; |
128 |
|
129 |
if ((ndx < 0) | (ndx >= ab->nangles)) |
130 |
return(0); |
131 |
for (li = 0; ndx >= ab->lat[li].nphis; li++) |
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ndx -= ab->lat[li].nphis; |
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theta1 = PI/180. * ab->lat[li+1].tmin; |
134 |
if (ab->lat[li].nphis == 1) { /* special case */ |
135 |
if (ab->lat[li].tmin > FTINY) |
136 |
error(USER, "unsupported BSDF coordinate system"); |
137 |
return(2.*PI*(1. - cos(theta1))); |
138 |
} |
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theta = PI/180. * ab->lat[li].tmin; |
140 |
return(2.*PI*(cos(theta) - cos(theta1))/(double)ab->lat[li].nphis); |
141 |
} |
142 |
|
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|
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static int |
145 |
ab_getvecR( /* get reverse vector for this angle basis index */ |
146 |
FVECT v, |
147 |
int ndx, |
148 |
void *p |
149 |
) |
150 |
{ |
151 |
if (!ab_getvec(v, ndx, p)) |
152 |
return(0); |
153 |
|
154 |
v[0] = -v[0]; |
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v[1] = -v[1]; |
156 |
v[2] = -v[2]; |
157 |
|
158 |
return(1); |
159 |
} |
160 |
|
161 |
|
162 |
static int |
163 |
ab_getndxR( /* get index corresponding to the reverse vector */ |
164 |
FVECT v, |
165 |
void *p |
166 |
) |
167 |
{ |
168 |
FVECT v2; |
169 |
|
170 |
v2[0] = -v[0]; |
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v2[1] = -v[1]; |
172 |
v2[2] = -v[2]; |
173 |
|
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return ab_getndx(v2, p); |
175 |
} |
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|
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|
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static void |
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load_bsdf_data( /* load BSDF distribution for this wavelength */ |
180 |
struct BSDF_data *dp, |
181 |
ezxml_t wdb |
182 |
) |
183 |
{ |
184 |
char *cbasis = ezxml_txt(ezxml_child(wdb,"ColumnAngleBasis")); |
185 |
char *rbasis = ezxml_txt(ezxml_child(wdb,"RowAngleBasis")); |
186 |
char *sdata; |
187 |
int i; |
188 |
|
189 |
if ((cbasis == NULL) | (rbasis == NULL)) { |
190 |
error(WARNING, "missing column/row basis for BSDF"); |
191 |
return; |
192 |
} |
193 |
/* XXX need to add routines for loading in foreign bases */ |
194 |
for (i = nabases; i--; ) |
195 |
if (!strcmp(cbasis, abase_list[i].name)) { |
196 |
dp->ninc = abase_list[i].nangles; |
197 |
dp->ib_priv = (void *)&abase_list[i]; |
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dp->ib_vec = ab_getvecR; |
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dp->ib_ndx = ab_getndxR; |
200 |
dp->ib_ohm = ab_getohm; |
201 |
break; |
202 |
} |
203 |
if (i < 0) { |
204 |
sprintf(errmsg, "unsupported ColumnAngleBasis '%s'", cbasis); |
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error(WARNING, errmsg); |
206 |
return; |
207 |
} |
208 |
for (i = nabases; i--; ) |
209 |
if (!strcmp(rbasis, abase_list[i].name)) { |
210 |
dp->nout = abase_list[i].nangles; |
211 |
dp->ob_priv = (void *)&abase_list[i]; |
212 |
dp->ob_vec = ab_getvec; |
213 |
dp->ob_ndx = ab_getndx; |
214 |
dp->ob_ohm = ab_getohm; |
215 |
break; |
216 |
} |
217 |
if (i < 0) { |
218 |
sprintf(errmsg, "unsupported RowAngleBasis '%s'", cbasis); |
219 |
error(WARNING, errmsg); |
220 |
return; |
221 |
} |
222 |
/* read BSDF data */ |
223 |
sdata = ezxml_txt(ezxml_child(wdb,"ScatteringData")); |
224 |
if (sdata == NULL) { |
225 |
error(WARNING, "missing BSDF ScatteringData"); |
226 |
return; |
227 |
} |
228 |
dp->bsdf = (float *)malloc(sizeof(float)*dp->ninc*dp->nout); |
229 |
if (dp->bsdf == NULL) |
230 |
error(SYSTEM, "out of memory in load_bsdf_data"); |
231 |
for (i = 0; i < dp->ninc*dp->nout; i++) { |
232 |
char *sdnext = fskip(sdata); |
233 |
if (sdnext == NULL) { |
234 |
error(WARNING, "bad/missing BSDF ScatteringData"); |
235 |
free(dp->bsdf); dp->bsdf = NULL; |
236 |
return; |
237 |
} |
238 |
while (*sdnext && isspace(*sdnext)) |
239 |
sdnext++; |
240 |
if (*sdnext == ',') sdnext++; |
241 |
dp->bsdf[i] = atof(sdata); |
242 |
sdata = sdnext; |
243 |
} |
244 |
while (isspace(*sdata)) |
245 |
sdata++; |
246 |
if (*sdata) { |
247 |
sprintf(errmsg, "%d extra characters after BSDF ScatteringData", |
248 |
strlen(sdata)); |
249 |
error(WARNING, errmsg); |
250 |
} |
251 |
} |
252 |
|
253 |
|
254 |
static int |
255 |
check_bsdf_data( /* check that BSDF data is sane */ |
256 |
struct BSDF_data *dp |
257 |
) |
258 |
{ |
259 |
double * omega_arr; |
260 |
double dom, hemi_total; |
261 |
int nneg; |
262 |
int i, o; |
263 |
|
264 |
if (dp == NULL || dp->bsdf == NULL) |
265 |
return(0); |
266 |
omega_arr = (double *)calloc(dp->nout, sizeof(double)); |
267 |
if (omega_arr == NULL) |
268 |
error(SYSTEM, "out of memory in check_bsdf_data"); |
269 |
hemi_total = .0; |
270 |
for (o = dp->nout; o--; ) { |
271 |
FVECT v; |
272 |
dom = getBSDF_outohm(dp,o); |
273 |
if (dom <= .0) { |
274 |
error(WARNING, "zero/negative solid angle"); |
275 |
continue; |
276 |
} |
277 |
if (!getBSDF_outvec(v,dp,o) || v[2] < -FTINY) { |
278 |
error(WARNING, "illegal outgoing BSDF direction"); |
279 |
free(omega_arr); |
280 |
return(0); |
281 |
} |
282 |
hemi_total += omega_arr[o] = dom*v[2]; |
283 |
} |
284 |
if ((hemi_total > 1.02*PI) | (hemi_total < 0.98*PI)) { |
285 |
sprintf(errmsg, "outgoing BSDF hemisphere off by %.1f%%", |
286 |
100.*(hemi_total/PI - 1.)); |
287 |
error(WARNING, errmsg); |
288 |
} |
289 |
dom = PI / hemi_total; /* normalize solid angles */ |
290 |
for (o = dp->nout; o--; ) |
291 |
omega_arr[o] *= dom; |
292 |
nneg = 0; |
293 |
for (i = dp->ninc; i--; ) { |
294 |
hemi_total = .0; |
295 |
for (o = dp->nout; o--; ) { |
296 |
double f = BSDF_value(dp,i,o); |
297 |
if (f > .0) |
298 |
hemi_total += f*omega_arr[o]; |
299 |
else if (f < -FTINY) |
300 |
++nneg; |
301 |
} |
302 |
if (hemi_total > 1.02) { |
303 |
sprintf(errmsg, "BSDF direction passes %.1f%% of light", |
304 |
100.*hemi_total); |
305 |
error(WARNING, errmsg); |
306 |
} |
307 |
} |
308 |
free(omega_arr); |
309 |
if (nneg > 0) { |
310 |
sprintf(errmsg, "%d negative BSDF values", nneg); |
311 |
error(WARNING, errmsg); |
312 |
return(0); |
313 |
} |
314 |
return(1); |
315 |
} |
316 |
|
317 |
struct BSDF_data * |
318 |
load_BSDF( /* load BSDF data from file */ |
319 |
char *fname |
320 |
) |
321 |
{ |
322 |
char *path; |
323 |
ezxml_t fl, wtl, wld, wdb; |
324 |
struct BSDF_data *dp; |
325 |
|
326 |
path = getpath(fname, getrlibpath(), R_OK); |
327 |
if (path == NULL) { |
328 |
sprintf(errmsg, "cannot find BSDF file \"%s\"", fname); |
329 |
error(WARNING, errmsg); |
330 |
return(NULL); |
331 |
} |
332 |
fl = ezxml_parse_file(path); |
333 |
if (fl == NULL) { |
334 |
sprintf(errmsg, "cannot open BSDF \"%s\"", path); |
335 |
error(WARNING, errmsg); |
336 |
return(NULL); |
337 |
} |
338 |
if (ezxml_error(fl)[0]) { |
339 |
sprintf(errmsg, "BSDF \"%s\" %s", path, ezxml_error(fl)); |
340 |
error(WARNING, errmsg); |
341 |
ezxml_free(fl); |
342 |
return(NULL); |
343 |
} |
344 |
if (strcmp(ezxml_name(fl), "WindowElement")) { |
345 |
sprintf(errmsg, |
346 |
"BSDF \"%s\": top level node not 'WindowElement'", |
347 |
path); |
348 |
error(WARNING, errmsg); |
349 |
ezxml_free(fl); |
350 |
return(NULL); |
351 |
} |
352 |
wtl = ezxml_child(ezxml_child(fl, "Optical"), "Layer"); |
353 |
dp = (struct BSDF_data *)calloc(1, sizeof(struct BSDF_data)); |
354 |
for (wld = ezxml_child(wtl, "WavelengthData"); |
355 |
wld != NULL; wld = wld->next) { |
356 |
if (strcmp(ezxml_txt(ezxml_child(wld,"Wavelength")), "Visible")) |
357 |
continue; |
358 |
wdb = ezxml_child(wld, "WavelengthDataBlock"); |
359 |
if (wdb == NULL) continue; |
360 |
if (strcmp(ezxml_txt(ezxml_child(wdb,"WavelengthDataDirection")), |
361 |
"Transmission Front")) |
362 |
continue; |
363 |
load_bsdf_data(dp, wdb); /* load front BTDF */ |
364 |
break; /* ignore the rest */ |
365 |
} |
366 |
ezxml_free(fl); /* done with XML file */ |
367 |
if (!check_bsdf_data(dp)) { |
368 |
sprintf(errmsg, "bad/missing BTDF data in \"%s\"", path); |
369 |
error(WARNING, errmsg); |
370 |
free_BSDF(dp); |
371 |
dp = NULL; |
372 |
} |
373 |
return(dp); |
374 |
} |
375 |
|
376 |
|
377 |
void |
378 |
free_BSDF( /* free BSDF data structure */ |
379 |
struct BSDF_data *b |
380 |
) |
381 |
{ |
382 |
if (b == NULL) |
383 |
return; |
384 |
if (b->bsdf != NULL) |
385 |
free(b->bsdf); |
386 |
free(b); |
387 |
} |
388 |
|
389 |
|
390 |
int |
391 |
r_BSDF_incvec( /* compute random input vector at given location */ |
392 |
FVECT v, |
393 |
struct BSDF_data *b, |
394 |
int i, |
395 |
double rv, |
396 |
MAT4 xm |
397 |
) |
398 |
{ |
399 |
FVECT pert; |
400 |
double rad; |
401 |
int j; |
402 |
|
403 |
if (!getBSDF_incvec(v, b, i)) |
404 |
return(0); |
405 |
rad = sqrt(getBSDF_incohm(b, i) / PI); |
406 |
multisamp(pert, 3, rv); |
407 |
for (j = 0; j < 3; j++) |
408 |
v[j] += rad*(2.*pert[j] - 1.); |
409 |
if (xm != NULL) |
410 |
multv3(v, v, xm); |
411 |
return(normalize(v) != 0.0); |
412 |
} |
413 |
|
414 |
|
415 |
int |
416 |
r_BSDF_outvec( /* compute random output vector at given location */ |
417 |
FVECT v, |
418 |
struct BSDF_data *b, |
419 |
int o, |
420 |
double rv, |
421 |
MAT4 xm |
422 |
) |
423 |
{ |
424 |
FVECT pert; |
425 |
double rad; |
426 |
int j; |
427 |
|
428 |
if (!getBSDF_outvec(v, b, o)) |
429 |
return(0); |
430 |
rad = sqrt(getBSDF_outohm(b, o) / PI); |
431 |
multisamp(pert, 3, rv); |
432 |
for (j = 0; j < 3; j++) |
433 |
v[j] += rad*(2.*pert[j] - 1.); |
434 |
if (xm != NULL) |
435 |
multv3(v, v, xm); |
436 |
return(normalize(v) != 0.0); |
437 |
} |
438 |
|
439 |
|
440 |
#define FEQ(a,b) ((a)-(b) <= 1e-7 && (b)-(a) <= 1e-7) |
441 |
|
442 |
static int |
443 |
addrot( /* compute rotation (x,y,z) => (xp,yp,zp) */ |
444 |
char *xfarg[], |
445 |
FVECT xp, |
446 |
FVECT yp, |
447 |
FVECT zp |
448 |
) |
449 |
{ |
450 |
static char bufs[3][16]; |
451 |
int bn = 0; |
452 |
char **xfp = xfarg; |
453 |
double theta; |
454 |
|
455 |
if (yp[2]*yp[2] + zp[2]*zp[2] < 2.*FTINY*FTINY) { |
456 |
/* Special case for X' along Z-axis */ |
457 |
theta = -atan2(yp[0], yp[1]); |
458 |
*xfp++ = "-ry"; |
459 |
*xfp++ = xp[2] < 0.0 ? "90" : "-90"; |
460 |
*xfp++ = "-rz"; |
461 |
sprintf(bufs[bn], "%f", theta*(180./PI)); |
462 |
*xfp++ = bufs[bn++]; |
463 |
return(xfp - xfarg); |
464 |
} |
465 |
theta = atan2(yp[2], zp[2]); |
466 |
if (!FEQ(theta,0.0)) { |
467 |
*xfp++ = "-rx"; |
468 |
sprintf(bufs[bn], "%f", theta*(180./PI)); |
469 |
*xfp++ = bufs[bn++]; |
470 |
} |
471 |
theta = asin(-xp[2]); |
472 |
if (!FEQ(theta,0.0)) { |
473 |
*xfp++ = "-ry"; |
474 |
sprintf(bufs[bn], " %f", theta*(180./PI)); |
475 |
*xfp++ = bufs[bn++]; |
476 |
} |
477 |
theta = atan2(xp[1], xp[0]); |
478 |
if (!FEQ(theta,0.0)) { |
479 |
*xfp++ = "-rz"; |
480 |
sprintf(bufs[bn], "%f", theta*(180./PI)); |
481 |
*xfp++ = bufs[bn++]; |
482 |
} |
483 |
*xfp = NULL; |
484 |
return(xfp - xfarg); |
485 |
} |
486 |
|
487 |
|
488 |
int |
489 |
getBSDF_xfm( /* compute BSDF orient. -> world orient. transform */ |
490 |
MAT4 xm, |
491 |
FVECT nrm, |
492 |
UpDir ud |
493 |
) |
494 |
{ |
495 |
char *xfargs[7]; |
496 |
XF myxf; |
497 |
FVECT updir, xdest, ydest; |
498 |
|
499 |
updir[0] = updir[1] = updir[2] = 0.; |
500 |
switch (ud) { |
501 |
case UDzneg: |
502 |
updir[2] = -1.; |
503 |
break; |
504 |
case UDyneg: |
505 |
updir[1] = -1.; |
506 |
break; |
507 |
case UDxneg: |
508 |
updir[0] = -1.; |
509 |
break; |
510 |
case UDxpos: |
511 |
updir[0] = 1.; |
512 |
break; |
513 |
case UDypos: |
514 |
updir[1] = 1.; |
515 |
break; |
516 |
case UDzpos: |
517 |
updir[2] = 1.; |
518 |
break; |
519 |
case UDunknown: |
520 |
return(0); |
521 |
} |
522 |
fcross(xdest, updir, nrm); |
523 |
if (normalize(xdest) == 0.0) |
524 |
return(0); |
525 |
fcross(ydest, nrm, xdest); |
526 |
xf(&myxf, addrot(xfargs, xdest, ydest, nrm), xfargs); |
527 |
copymat4(xm, myxf.xfm); |
528 |
return(1); |
529 |
} |
530 |
|
531 |
|
532 |
void |
533 |
redistribute( /* pass distarr ray sums through BSDF */ |
534 |
struct BSDF_data *b, |
535 |
int nalt, |
536 |
int nazi, |
537 |
FVECT u, |
538 |
FVECT v, |
539 |
FVECT w, |
540 |
MAT4 xm |
541 |
) |
542 |
{ |
543 |
int nout = 0; |
544 |
MAT4 mymat, inmat; |
545 |
COLORV *idist; |
546 |
COLORV *cp; |
547 |
FVECT dv; |
548 |
double wt; |
549 |
int i, j, k, c, o; |
550 |
COLOR col, cinc; |
551 |
/* copy incoming distribution */ |
552 |
if (b->ninc > distsiz) |
553 |
error(INTERNAL, "error 1 in redistribute"); |
554 |
idist = (COLORV *)malloc(sizeof(COLOR)*b->ninc); |
555 |
if (idist == NULL) |
556 |
error(SYSTEM, "out of memory in redistribute"); |
557 |
memcpy(idist, distarr, sizeof(COLOR)*b->ninc); |
558 |
/* compose direction transform */ |
559 |
for (i = 3; i--; ) { |
560 |
mymat[i][0] = u[i]; |
561 |
mymat[i][1] = v[i]; |
562 |
mymat[i][2] = w[i]; |
563 |
mymat[i][3] = 0.; |
564 |
} |
565 |
mymat[3][0] = mymat[3][1] = mymat[3][2] = 0.; |
566 |
mymat[3][3] = 1.; |
567 |
if (xm != NULL) |
568 |
multmat4(mymat, xm, mymat); |
569 |
for (i = 3; i--; ) { /* make sure it's normalized */ |
570 |
wt = 1./sqrt( mymat[0][i]*mymat[0][i] + |
571 |
mymat[1][i]*mymat[1][i] + |
572 |
mymat[2][i]*mymat[2][i] ); |
573 |
for (j = 3; j--; ) |
574 |
mymat[j][i] *= wt; |
575 |
} |
576 |
if (!invmat4(inmat, mymat)) /* need inverse as well */ |
577 |
error(INTERNAL, "cannot invert BSDF transform"); |
578 |
newdist(nalt*nazi); /* resample distribution */ |
579 |
for (i = b->ninc; i--; ) { |
580 |
int direct_out = -1; |
581 |
COLOR cdir; |
582 |
getBSDF_incvec(dv, b, i); /* compute incident irrad. */ |
583 |
multv3(dv, dv, mymat); |
584 |
if (dv[2] < 0.0) { |
585 |
dv[0] = -dv[0]; dv[1] = -dv[1]; dv[2] = -dv[2]; |
586 |
direct_out += (direct_discount != NULL); |
587 |
} |
588 |
wt = getBSDF_incohm(b, i); |
589 |
wt *= dv[2]; /* solid_angle*cosine(theta) */ |
590 |
cp = &idist[3*i]; |
591 |
copycolor(cinc, cp); |
592 |
scalecolor(cinc, wt); |
593 |
if (!direct_out) { /* discount direct contr. */ |
594 |
cp = &direct_discount[3*i]; |
595 |
copycolor(cdir, cp); |
596 |
scalecolor(cdir, -wt); |
597 |
direct_out = flatindex(dv, nalt, nazi); |
598 |
} |
599 |
for (k = nalt; k--; ) /* loop over distribution */ |
600 |
for (j = nazi; j--; ) { |
601 |
int rstart = random(); |
602 |
for (c = NBSDFSAMPS; c--; ) { |
603 |
double sp[2]; |
604 |
multisamp(sp, 2, urand(rstart+c)); |
605 |
flatdir(dv, (k + sp[0])/nalt, |
606 |
(j + .5 - sp[1])/nazi); |
607 |
multv3(dv, dv, inmat); |
608 |
/* evaluate BSDF @ outgoing */ |
609 |
o = getBSDF_outndx(b, dv); |
610 |
if (o < 0) { |
611 |
nout++; |
612 |
continue; |
613 |
} |
614 |
wt = BSDF_value(b, i, o) * (1./NBSDFSAMPS); |
615 |
copycolor(col, cinc); |
616 |
o = k*nazi + j; |
617 |
if (o == direct_out) |
618 |
addcolor(col, cdir); /* minus direct */ |
619 |
scalecolor(col, wt); |
620 |
cp = &distarr[3*o]; |
621 |
addcolor(cp, col); /* sum into distribution */ |
622 |
} |
623 |
} |
624 |
} |
625 |
free(idist); /* free temp space */ |
626 |
if (nout) { |
627 |
sprintf(errmsg, "missing %.1f%% of BSDF directions", |
628 |
100.*nout/(b->ninc*nalt*nazi*NBSDFSAMPS)); |
629 |
error(WARNING, errmsg); |
630 |
} |
631 |
} |