1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: bsdf_m.c,v 3.45 2022/01/25 01:34:20 greg Exp $"; |
3 |
#endif |
4 |
/* |
5 |
* bsdf_m.c |
6 |
* |
7 |
* Definitions supporting BSDF matrices |
8 |
* |
9 |
* Created by Greg Ward on 2/2/11. |
10 |
* Copyright 2011 Anyhere Software. All rights reserved. |
11 |
* |
12 |
*/ |
13 |
|
14 |
#define _USE_MATH_DEFINES |
15 |
#include "rtio.h" |
16 |
#include <math.h> |
17 |
#include <ctype.h> |
18 |
#include "ezxml.h" |
19 |
#include "bsdf.h" |
20 |
#include "bsdf_m.h" |
21 |
|
22 |
/* Function return codes */ |
23 |
#define RC_GOOD 1 |
24 |
#define RC_FAIL 0 |
25 |
#define RC_FORMERR (-1) |
26 |
#define RC_DATERR (-2) |
27 |
#define RC_UNSUPP (-3) |
28 |
#define RC_INTERR (-4) |
29 |
#define RC_MEMERR (-5) |
30 |
|
31 |
ANGLE_BASIS abase_list[MAXABASES] = { |
32 |
{ |
33 |
"LBNL/Klems Full", 145, |
34 |
{ {0., 1}, |
35 |
{5., 8}, |
36 |
{15., 16}, |
37 |
{25., 20}, |
38 |
{35., 24}, |
39 |
{45., 24}, |
40 |
{55., 24}, |
41 |
{65., 16}, |
42 |
{75., 12}, |
43 |
{90., 0} } |
44 |
}, { |
45 |
"LBNL/Klems Half", 77, |
46 |
{ {0., 1}, |
47 |
{6.5, 8}, |
48 |
{19.5, 12}, |
49 |
{32.5, 16}, |
50 |
{45.5, 20}, |
51 |
{58.5, 12}, |
52 |
{71.5, 8}, |
53 |
{90., 0} } |
54 |
}, { |
55 |
"LBNL/Klems Quarter", 41, |
56 |
{ {0., 1}, |
57 |
{9., 8}, |
58 |
{27., 12}, |
59 |
{45., 12}, |
60 |
{63., 8}, |
61 |
{90., 0} } |
62 |
} |
63 |
}; |
64 |
|
65 |
int nabases = 3; /* current number of defined bases */ |
66 |
|
67 |
C_COLOR mtx_RGB_prim[3]; /* our RGB primaries */ |
68 |
float mtx_RGB_coef[3]; /* corresponding Y coefficients */ |
69 |
|
70 |
enum {mtx_Y, mtx_X, mtx_Z}; /* matrix components (mtx_Y==0) */ |
71 |
|
72 |
/* check if two real values are near enough to equal */ |
73 |
static int |
74 |
fequal(double a, double b) |
75 |
{ |
76 |
if (b != 0) |
77 |
a = a/b - 1.; |
78 |
return (a <= 1e-6) & (a >= -1e-6); |
79 |
} |
80 |
|
81 |
/* convert error to standard BSDF code */ |
82 |
static SDError |
83 |
convert_errcode(int ec) |
84 |
{ |
85 |
switch (ec) { |
86 |
case RC_GOOD: |
87 |
return SDEnone; |
88 |
case RC_FORMERR: |
89 |
return SDEformat; |
90 |
case RC_DATERR: |
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return SDEdata; |
92 |
case RC_UNSUPP: |
93 |
return SDEsupport; |
94 |
case RC_INTERR: |
95 |
return SDEinternal; |
96 |
case RC_MEMERR: |
97 |
return SDEmemory; |
98 |
} |
99 |
return SDEunknown; |
100 |
} |
101 |
|
102 |
/* allocate a BSDF matrix of the given size */ |
103 |
static SDMat * |
104 |
SDnewMatrix(int ni, int no) |
105 |
{ |
106 |
SDMat *sm; |
107 |
|
108 |
if ((ni <= 0) | (no <= 0)) { |
109 |
strcpy(SDerrorDetail, "Empty BSDF matrix request"); |
110 |
return NULL; |
111 |
} |
112 |
sm = (SDMat *)malloc(sizeof(SDMat) + (ni*no - 1)*sizeof(float)); |
113 |
if (sm == NULL) { |
114 |
sprintf(SDerrorDetail, "Cannot allocate %dx%d BSDF matrix", |
115 |
ni, no); |
116 |
return NULL; |
117 |
} |
118 |
memset(sm, 0, sizeof(SDMat)-sizeof(float)); |
119 |
sm->ninc = ni; |
120 |
sm->nout = no; |
121 |
|
122 |
return sm; |
123 |
} |
124 |
|
125 |
/* Free a BSDF matrix */ |
126 |
void |
127 |
SDfreeMatrix(void *ptr) |
128 |
{ |
129 |
SDMat *mp = (SDMat *)ptr; |
130 |
|
131 |
if (mp->chroma != NULL) free(mp->chroma); |
132 |
free(ptr); |
133 |
} |
134 |
|
135 |
/* compute square of real value */ |
136 |
static double sq(double x) { return x*x; } |
137 |
|
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/* Get vector for this angle basis index (front exiting) */ |
139 |
int |
140 |
fo_getvec(FVECT v, double ndxr, void *p) |
141 |
{ |
142 |
ANGLE_BASIS *ab = (ANGLE_BASIS *)p; |
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int ndx = (int)ndxr; |
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double randX = ndxr - ndx; |
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double rx[2]; |
146 |
int li; |
147 |
double azi, d; |
148 |
|
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if ((ndxr < 0) | (ndx >= ab->nangles)) |
150 |
return RC_FAIL; |
151 |
for (li = 0; ndx >= ab->lat[li].nphis; li++) |
152 |
ndx -= ab->lat[li].nphis; |
153 |
SDmultiSamp(rx, 2, randX); |
154 |
d = (1. - rx[0])*sq(cos(M_PI/180.*ab->lat[li].tmin)) + |
155 |
rx[0]*sq(cos(M_PI/180.*ab->lat[li+1].tmin)); |
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v[2] = d = sqrt(d); /* cos(pol) */ |
157 |
azi = 2.*M_PI*(ndx + rx[1] - .5)/ab->lat[li].nphis; |
158 |
d = sqrt(1. - d*d); /* sin(pol) */ |
159 |
v[0] = cos(azi)*d; |
160 |
v[1] = sin(azi)*d; |
161 |
return RC_GOOD; |
162 |
} |
163 |
|
164 |
/* Get index corresponding to the given vector (front exiting) */ |
165 |
int |
166 |
fo_getndx(const FVECT v, void *p) |
167 |
{ |
168 |
ANGLE_BASIS *ab = (ANGLE_BASIS *)p; |
169 |
int li, ndx; |
170 |
double pol, azi; |
171 |
|
172 |
if (v == NULL) |
173 |
return -1; |
174 |
if ((v[2] < 0) | (v[2] > 1.00001)) |
175 |
return -1; |
176 |
pol = 180.0/M_PI*Acos(v[2]); |
177 |
azi = 180.0/M_PI*atan2(v[1], v[0]); |
178 |
if (azi < 0.0) azi += 360.0; |
179 |
for (li = 1; ab->lat[li].tmin <= pol; li++) |
180 |
if (!ab->lat[li].nphis) |
181 |
return -1; |
182 |
--li; |
183 |
ndx = (int)((1./360.)*azi*ab->lat[li].nphis + 0.5); |
184 |
if (ndx >= ab->lat[li].nphis) ndx = 0; |
185 |
while (li--) |
186 |
ndx += ab->lat[li].nphis; |
187 |
return ndx; |
188 |
} |
189 |
|
190 |
/* Get projected solid angle for this angle basis index (universal) */ |
191 |
double |
192 |
io_getohm(int ndx, void *p) |
193 |
{ |
194 |
static void *last_p = NULL; |
195 |
static int last_li = -1; |
196 |
static double last_ohm; |
197 |
ANGLE_BASIS *ab = (ANGLE_BASIS *)p; |
198 |
int li; |
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double theta, theta1; |
200 |
|
201 |
if ((ndx < 0) | (ndx >= ab->nangles)) |
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return -1.; |
203 |
for (li = 0; ndx >= ab->lat[li].nphis; li++) |
204 |
ndx -= ab->lat[li].nphis; |
205 |
if ((p == last_p) & (li == last_li)) /* cached latitude? */ |
206 |
return last_ohm; |
207 |
last_p = p; |
208 |
last_li = li; |
209 |
theta = M_PI/180. * ab->lat[li].tmin; |
210 |
theta1 = M_PI/180. * ab->lat[li+1].tmin; |
211 |
return last_ohm = M_PI*(sq(cos(theta)) - sq(cos(theta1))) / |
212 |
(double)ab->lat[li].nphis; |
213 |
} |
214 |
|
215 |
/* Get vector for this angle basis index (back incident) */ |
216 |
int |
217 |
bi_getvec(FVECT v, double ndxr, void *p) |
218 |
{ |
219 |
if (!fo_getvec(v, ndxr, p)) |
220 |
return RC_FAIL; |
221 |
|
222 |
v[0] = -v[0]; |
223 |
v[1] = -v[1]; |
224 |
v[2] = -v[2]; |
225 |
|
226 |
return RC_GOOD; |
227 |
} |
228 |
|
229 |
/* Get index corresponding to the vector (back incident) */ |
230 |
int |
231 |
bi_getndx(const FVECT v, void *p) |
232 |
{ |
233 |
FVECT v2; |
234 |
|
235 |
v2[0] = -v[0]; |
236 |
v2[1] = -v[1]; |
237 |
v2[2] = -v[2]; |
238 |
|
239 |
return fo_getndx(v2, p); |
240 |
} |
241 |
|
242 |
/* Get vector for this angle basis index (back exiting) */ |
243 |
int |
244 |
bo_getvec(FVECT v, double ndxr, void *p) |
245 |
{ |
246 |
if (!fo_getvec(v, ndxr, p)) |
247 |
return RC_FAIL; |
248 |
|
249 |
v[2] = -v[2]; |
250 |
|
251 |
return RC_GOOD; |
252 |
} |
253 |
|
254 |
/* Get index corresponding to the vector (back exiting) */ |
255 |
int |
256 |
bo_getndx(const FVECT v, void *p) |
257 |
{ |
258 |
FVECT v2; |
259 |
|
260 |
v2[0] = v[0]; |
261 |
v2[1] = v[1]; |
262 |
v2[2] = -v[2]; |
263 |
|
264 |
return fo_getndx(v2, p); |
265 |
} |
266 |
|
267 |
/* Get vector for this angle basis index (front incident) */ |
268 |
int |
269 |
fi_getvec(FVECT v, double ndxr, void *p) |
270 |
{ |
271 |
if (!fo_getvec(v, ndxr, p)) |
272 |
return RC_FAIL; |
273 |
|
274 |
v[0] = -v[0]; |
275 |
v[1] = -v[1]; |
276 |
|
277 |
return RC_GOOD; |
278 |
} |
279 |
|
280 |
/* Get index corresponding to the vector (front incident) */ |
281 |
int |
282 |
fi_getndx(const FVECT v, void *p) |
283 |
{ |
284 |
FVECT v2; |
285 |
|
286 |
v2[0] = -v[0]; |
287 |
v2[1] = -v[1]; |
288 |
v2[2] = v[2]; |
289 |
|
290 |
return fo_getndx(v2, p); |
291 |
} |
292 |
|
293 |
/* Get color or grayscale value for BSDF for the given direction pair */ |
294 |
int |
295 |
mBSDF_color(float coef[], const SDMat *dp, int i, int o) |
296 |
{ |
297 |
C_COLOR cxy; |
298 |
double d; |
299 |
|
300 |
coef[0] = mBSDF_value(dp, o, i); |
301 |
/* position-specific perturbation */ |
302 |
d = 2*dp->ninc/(i + .22545) + 4*dp->nout/(o + .70281); |
303 |
d -= (int)d; |
304 |
coef[0] *= 1. + 6e-4*(d - .5); |
305 |
if (dp->chroma == NULL) |
306 |
return 1; /* grayscale */ |
307 |
|
308 |
c_decodeChroma(&cxy, mBSDF_chroma(dp,o,i)); |
309 |
c_toSharpRGB(&cxy, coef[0], coef); |
310 |
coef[0] *= mtx_RGB_coef[0]; |
311 |
coef[1] *= mtx_RGB_coef[1]; |
312 |
coef[2] *= mtx_RGB_coef[2]; |
313 |
return 3; /* RGB color */ |
314 |
} |
315 |
|
316 |
/* load custom BSDF angle basis */ |
317 |
static int |
318 |
load_angle_basis(ezxml_t wab) |
319 |
{ |
320 |
char *abname = ezxml_txt(ezxml_child(wab, "AngleBasisName")); |
321 |
ezxml_t wbb; |
322 |
int i; |
323 |
|
324 |
if (!abname || !*abname) |
325 |
return RC_FAIL; |
326 |
for (i = nabases; i--; ) |
327 |
if (!strcasecmp(abname, abase_list[i].name)) |
328 |
return RC_GOOD; /* assume it's the same */ |
329 |
if (nabases >= MAXABASES) { |
330 |
sprintf(SDerrorDetail, "Out of angle bases reading '%s'", |
331 |
abname); |
332 |
return RC_INTERR; |
333 |
} |
334 |
strcpy(abase_list[nabases].name, abname); |
335 |
abase_list[nabases].nangles = 0; |
336 |
for (i = 0, wbb = ezxml_child(wab, "AngleBasisBlock"); |
337 |
wbb != NULL; i++, wbb = wbb->next) { |
338 |
if (i >= MAXLATS) { |
339 |
sprintf(SDerrorDetail, "Too many latitudes for '%s'", |
340 |
abname); |
341 |
return RC_INTERR; |
342 |
} |
343 |
abase_list[nabases].lat[i+1].tmin = atof(ezxml_txt( |
344 |
ezxml_child(ezxml_child(wbb, |
345 |
"ThetaBounds"), "UpperTheta"))); |
346 |
if (!i) |
347 |
abase_list[nabases].lat[0].tmin = 0; |
348 |
else if (!fequal(atof(ezxml_txt(ezxml_child(ezxml_child(wbb, |
349 |
"ThetaBounds"), "LowerTheta"))), |
350 |
abase_list[nabases].lat[i].tmin)) { |
351 |
sprintf(SDerrorDetail, "Theta values disagree in '%s'", |
352 |
abname); |
353 |
return RC_DATERR; |
354 |
} |
355 |
abase_list[nabases].nangles += |
356 |
abase_list[nabases].lat[i].nphis = |
357 |
atoi(ezxml_txt(ezxml_child(wbb, "nPhis"))); |
358 |
if (abase_list[nabases].lat[i].nphis <= 0 || |
359 |
(abase_list[nabases].lat[i].nphis == 1 && |
360 |
abase_list[nabases].lat[i].tmin > FTINY)) { |
361 |
sprintf(SDerrorDetail, "Illegal phi count in '%s'", |
362 |
abname); |
363 |
return RC_DATERR; |
364 |
} |
365 |
} |
366 |
abase_list[nabases++].lat[i].nphis = 0; |
367 |
return RC_GOOD; |
368 |
} |
369 |
|
370 |
/* compute min. proj. solid angle and max. direct hemispherical scattering */ |
371 |
static int |
372 |
get_extrema(SDSpectralDF *df) |
373 |
{ |
374 |
SDMat *dp = (SDMat *)df->comp[0].dist; |
375 |
double *ohma; |
376 |
int i, o; |
377 |
/* initialize extrema */ |
378 |
df->minProjSA = M_PI; |
379 |
df->maxHemi = .0; |
380 |
ohma = (double *)malloc(dp->nout*sizeof(double)); |
381 |
if (ohma == NULL) |
382 |
return RC_MEMERR; |
383 |
/* get outgoing solid angles */ |
384 |
for (o = dp->nout; o--; ) |
385 |
if ((ohma[o] = mBSDF_outohm(dp,o)) < df->minProjSA) |
386 |
df->minProjSA = ohma[o]; |
387 |
/* compute hemispherical sums */ |
388 |
for (i = dp->ninc; i--; ) { |
389 |
double hemi = .0; |
390 |
for (o = dp->nout; o--; ) |
391 |
hemi += ohma[o] * mBSDF_value(dp, o, i); |
392 |
if (hemi > df->maxHemi) |
393 |
df->maxHemi = hemi; |
394 |
} |
395 |
free(ohma); |
396 |
/* need incoming solid angles, too? */ |
397 |
if ((dp->ib_ohm != dp->ob_ohm) | (dp->ib_priv != dp->ob_priv)) { |
398 |
double ohm; |
399 |
for (i = dp->ninc; i--; ) |
400 |
if ((ohm = mBSDF_incohm(dp,i)) < df->minProjSA) |
401 |
df->minProjSA = ohm; |
402 |
} |
403 |
return (df->maxHemi <= 1.01); |
404 |
} |
405 |
|
406 |
/* load BSDF distribution for this wavelength */ |
407 |
static int |
408 |
load_bsdf_data(SDData *sd, ezxml_t wdb, int ct, int rowinc) |
409 |
{ |
410 |
SDSpectralDF *df; |
411 |
SDMat *dp; |
412 |
char *sdata; |
413 |
int inbi, outbi; |
414 |
int i; |
415 |
/* allocate BSDF component */ |
416 |
sdata = ezxml_txt(ezxml_child(wdb, "WavelengthDataDirection")); |
417 |
if (!sdata) |
418 |
return RC_FAIL; |
419 |
/* |
420 |
* Remember that front and back are reversed from WINDOW 6 orientations |
421 |
*/ |
422 |
if (!strcasecmp(sdata, "Transmission Front")) { |
423 |
if (sd->tb == NULL && (sd->tb = SDnewSpectralDF(3)) == NULL) |
424 |
return RC_MEMERR; |
425 |
df = sd->tb; |
426 |
} else if (!strcasecmp(sdata, "Transmission Back")) { |
427 |
if (sd->tf == NULL && (sd->tf = SDnewSpectralDF(3)) == NULL) |
428 |
return RC_MEMERR; |
429 |
df = sd->tf; |
430 |
} else if (!strcasecmp(sdata, "Reflection Front")) { |
431 |
if (sd->rb == NULL && (sd->rb = SDnewSpectralDF(3)) == NULL) |
432 |
return RC_MEMERR; |
433 |
df = sd->rb; |
434 |
} else if (!strcasecmp(sdata, "Reflection Back")) { |
435 |
if (sd->rf == NULL && (sd->rf = SDnewSpectralDF(3)) == NULL) |
436 |
return RC_MEMERR; |
437 |
df = sd->rf; |
438 |
} else |
439 |
return RC_FAIL; |
440 |
/* free previous matrix if any */ |
441 |
if (df->comp[ct].dist != NULL) { |
442 |
SDfreeMatrix(df->comp[ct].dist); |
443 |
df->comp[ct].dist = NULL; |
444 |
} |
445 |
/* get angle bases */ |
446 |
sdata = ezxml_txt(ezxml_child(wdb,"ColumnAngleBasis")); |
447 |
if (!sdata || !*sdata) { |
448 |
sprintf(SDerrorDetail, "Missing column basis for BSDF '%s'", |
449 |
sd->name); |
450 |
return RC_FORMERR; |
451 |
} |
452 |
for (inbi = nabases; inbi--; ) |
453 |
if (!strcasecmp(sdata, abase_list[inbi].name)) |
454 |
break; |
455 |
if (inbi < 0) { |
456 |
sprintf(SDerrorDetail, "Undefined ColumnAngleBasis '%s'", sdata); |
457 |
return RC_FORMERR; |
458 |
} |
459 |
sdata = ezxml_txt(ezxml_child(wdb,"RowAngleBasis")); |
460 |
if (!sdata || !*sdata) { |
461 |
sprintf(SDerrorDetail, "Missing row basis for BSDF '%s'", |
462 |
sd->name); |
463 |
return RC_FORMERR; |
464 |
} |
465 |
for (outbi = nabases; outbi--; ) |
466 |
if (!strcasecmp(sdata, abase_list[outbi].name)) |
467 |
break; |
468 |
if (outbi < 0) { |
469 |
sprintf(SDerrorDetail, "Undefined RowAngleBasis '%s'", sdata); |
470 |
return RC_FORMERR; |
471 |
} |
472 |
/* allocate BSDF matrix */ |
473 |
dp = SDnewMatrix(abase_list[inbi].nangles, abase_list[outbi].nangles); |
474 |
if (dp == NULL) |
475 |
return RC_MEMERR; |
476 |
dp->ib_priv = &abase_list[inbi]; |
477 |
dp->ob_priv = &abase_list[outbi]; |
478 |
if (df == sd->tf) { |
479 |
dp->ib_vec = &fi_getvec; |
480 |
dp->ib_ndx = &fi_getndx; |
481 |
dp->ob_vec = &bo_getvec; |
482 |
dp->ob_ndx = &bo_getndx; |
483 |
} else if (df == sd->tb) { |
484 |
dp->ib_vec = &bi_getvec; |
485 |
dp->ib_ndx = &bi_getndx; |
486 |
dp->ob_vec = &fo_getvec; |
487 |
dp->ob_ndx = &fo_getndx; |
488 |
} else if (df == sd->rf) { |
489 |
dp->ib_vec = &fi_getvec; |
490 |
dp->ib_ndx = &fi_getndx; |
491 |
dp->ob_vec = &fo_getvec; |
492 |
dp->ob_ndx = &fo_getndx; |
493 |
} else /* df == sd->rb */ { |
494 |
dp->ib_vec = &bi_getvec; |
495 |
dp->ib_ndx = &bi_getndx; |
496 |
dp->ob_vec = &bo_getvec; |
497 |
dp->ob_ndx = &bo_getndx; |
498 |
} |
499 |
dp->ib_ohm = &io_getohm; |
500 |
dp->ob_ohm = &io_getohm; |
501 |
df->comp[ct].dist = dp; |
502 |
df->comp[ct].func = &SDhandleMtx; |
503 |
/* read BSDF data */ |
504 |
sdata = ezxml_txt(ezxml_child(wdb, "ScatteringData")); |
505 |
if (!sdata || !*sdata) { |
506 |
sprintf(SDerrorDetail, "Missing BSDF ScatteringData in '%s'", |
507 |
sd->name); |
508 |
return RC_FORMERR; |
509 |
} |
510 |
for (i = 0; i < dp->ninc*dp->nout; i++) { |
511 |
char *sdnext = fskip(sdata); |
512 |
double val; |
513 |
if (sdnext == NULL) { |
514 |
sprintf(SDerrorDetail, |
515 |
"Bad/missing BSDF ScatteringData in '%s'", |
516 |
sd->name); |
517 |
return RC_FORMERR; |
518 |
} |
519 |
while (isspace(*sdnext)) |
520 |
sdnext++; |
521 |
if (*sdnext == ',') sdnext++; |
522 |
if ((val = atof(sdata)) < 0) |
523 |
val = 0; /* don't allow negative values */ |
524 |
if (rowinc) { |
525 |
int r = i/dp->nout; |
526 |
int c = i - r*dp->nout; |
527 |
mBSDF_value(dp,c,r) = val; |
528 |
} else |
529 |
dp->bsdf[i] = val; |
530 |
sdata = sdnext; |
531 |
} |
532 |
return (ct == mtx_Y) ? get_extrema(df) : RC_GOOD; |
533 |
} |
534 |
|
535 |
/* copy our RGB (x,y) primary chromaticities */ |
536 |
static void |
537 |
copy_RGB_prims(C_COLOR cspec[]) |
538 |
{ |
539 |
if (mtx_RGB_coef[1] < .001) { /* need to initialize */ |
540 |
int i = 3; |
541 |
while (i--) { |
542 |
float rgb[3]; |
543 |
rgb[0] = rgb[1] = rgb[2] = .0f; |
544 |
rgb[i] = 1.f; |
545 |
mtx_RGB_coef[i] = c_fromSharpRGB(rgb, &mtx_RGB_prim[i]); |
546 |
} |
547 |
} |
548 |
memcpy(cspec, mtx_RGB_prim, sizeof(mtx_RGB_prim)); |
549 |
} |
550 |
|
551 |
/* encode chromaticity if XYZ -- reduce to one channel in any case */ |
552 |
static SDSpectralDF * |
553 |
encode_chroma(SDSpectralDF *df) |
554 |
{ |
555 |
SDMat *mpx, *mpy, *mpz; |
556 |
int n; |
557 |
|
558 |
if (df == NULL || df->ncomp != 3) |
559 |
return df; |
560 |
|
561 |
mpy = (SDMat *)df->comp[mtx_Y].dist; |
562 |
if (mpy == NULL) { |
563 |
free(df); |
564 |
return NULL; |
565 |
} |
566 |
mpx = (SDMat *)df->comp[mtx_X].dist; |
567 |
mpz = (SDMat *)df->comp[mtx_Z].dist; |
568 |
if (mpx == NULL || (mpx->ninc != mpy->ninc) | (mpx->nout != mpy->nout)) |
569 |
goto done; |
570 |
if (mpz == NULL || (mpz->ninc != mpy->ninc) | (mpz->nout != mpy->nout)) |
571 |
goto done; |
572 |
mpy->chroma = (C_CHROMA *)malloc(sizeof(C_CHROMA)*mpy->ninc*mpy->nout); |
573 |
if (mpy->chroma == NULL) |
574 |
goto done; /* XXX punt */ |
575 |
/* encode chroma values */ |
576 |
for (n = mpy->ninc*mpy->nout; n--; ) { |
577 |
const double sum = mpx->bsdf[n] + mpy->bsdf[n] + mpz->bsdf[n]; |
578 |
C_COLOR cxy; |
579 |
if (sum > .0) |
580 |
c_cset(&cxy, mpx->bsdf[n]/sum, mpy->bsdf[n]/sum); |
581 |
else |
582 |
c_cset(&cxy, 1./3., 1./3.); |
583 |
mpy->chroma[n] = c_encodeChroma(&cxy); |
584 |
} |
585 |
done: /* free X & Z channels */ |
586 |
if (mpx != NULL) SDfreeMatrix(mpx); |
587 |
if (mpz != NULL) SDfreeMatrix(mpz); |
588 |
if (mpy->chroma == NULL) /* grayscale after all? */ |
589 |
df->comp[0].cspec[0] = c_dfcolor; |
590 |
else /* else copy RGB primaries */ |
591 |
copy_RGB_prims(df->comp[0].cspec); |
592 |
df->ncomp = 1; /* return resized struct */ |
593 |
return (SDSpectralDF *)realloc(df, sizeof(SDSpectralDF)); |
594 |
} |
595 |
|
596 |
/* subtract minimum (diffuse) scattering amount from BSDF */ |
597 |
static double |
598 |
subtract_min(C_COLOR *cs, SDMat *sm) |
599 |
{ |
600 |
const int ncomp = 1 + 2*(sm->chroma != NULL); |
601 |
float min_coef[3], ymin, coef[3]; |
602 |
int i, o, c; |
603 |
|
604 |
min_coef[0] = min_coef[1] = min_coef[2] = FHUGE; |
605 |
for (i = 0; i < sm->ninc; i++) |
606 |
for (o = 0; o < sm->nout; o++) { |
607 |
c = mBSDF_color(coef, sm, i, o); |
608 |
while (c--) |
609 |
if (coef[c] < min_coef[c]) |
610 |
min_coef[c] = coef[c]; |
611 |
} |
612 |
ymin = 0; |
613 |
for (c = ncomp; c--; ) |
614 |
ymin += min_coef[c]; |
615 |
if (ymin <= .01/M_PI) /* not worth bothering about? */ |
616 |
return .0; |
617 |
if (ncomp == 1) { /* subtract grayscale minimum */ |
618 |
for (i = sm->ninc*sm->nout; i--; ) |
619 |
sm->bsdf[i] -= ymin; |
620 |
*cs = c_dfcolor; |
621 |
return M_PI*ymin; |
622 |
} |
623 |
/* else subtract colored minimum */ |
624 |
for (i = 0; i < sm->ninc; i++) |
625 |
for (o = 0; o < sm->nout; o++) { |
626 |
C_COLOR cxy; |
627 |
c = mBSDF_color(coef, sm, i, o); |
628 |
while (c--) |
629 |
coef[c] = (coef[c] - min_coef[c]) / |
630 |
mtx_RGB_coef[c]; |
631 |
if (c_fromSharpRGB(coef, &cxy) > 1e-5) |
632 |
mBSDF_chroma(sm,o,i) = c_encodeChroma(&cxy); |
633 |
mBSDF_value(sm,o,i) -= ymin; |
634 |
} |
635 |
/* return colored minimum */ |
636 |
for (i = 3; i--; ) |
637 |
coef[i] = min_coef[i]/mtx_RGB_coef[i]; |
638 |
c_fromSharpRGB(coef, cs); |
639 |
|
640 |
return M_PI*ymin; |
641 |
} |
642 |
|
643 |
/* Extract and separate diffuse portion of BSDF & convert color */ |
644 |
static SDSpectralDF * |
645 |
extract_diffuse(SDValue *dv, SDSpectralDF *df) |
646 |
{ |
647 |
|
648 |
df = encode_chroma(df); /* reduce XYZ to Y + chroma */ |
649 |
if (df == NULL || df->ncomp <= 0) { |
650 |
dv->spec = c_dfcolor; |
651 |
dv->cieY = .0; |
652 |
return df; |
653 |
} |
654 |
/* subtract minimum value */ |
655 |
dv->cieY = subtract_min(&dv->spec, (SDMat *)df->comp[0].dist); |
656 |
df->maxHemi -= dv->cieY; /* adjust maximum hemispherical */ |
657 |
|
658 |
c_ccvt(&dv->spec, C_CSXY); /* make sure (x,y) is set */ |
659 |
return df; |
660 |
} |
661 |
|
662 |
/* Load a BSDF matrix from an open XML file */ |
663 |
SDError |
664 |
SDloadMtx(SDData *sd, ezxml_t wtl) |
665 |
{ |
666 |
ezxml_t wld, wdb; |
667 |
int rowIn; |
668 |
char *txt; |
669 |
int rval; |
670 |
/* basic checks and data ordering */ |
671 |
txt = ezxml_txt(ezxml_child(ezxml_child(wtl, |
672 |
"DataDefinition"), "IncidentDataStructure")); |
673 |
if (txt == NULL || !*txt) { |
674 |
sprintf(SDerrorDetail, |
675 |
"BSDF \"%s\": missing IncidentDataStructure", |
676 |
sd->name); |
677 |
return SDEformat; |
678 |
} |
679 |
if (!strcasecmp(txt, "Rows")) |
680 |
rowIn = 1; |
681 |
else if (!strcasecmp(txt, "Columns")) |
682 |
rowIn = 0; |
683 |
else { |
684 |
sprintf(SDerrorDetail, |
685 |
"BSDF \"%s\": unsupported IncidentDataStructure", |
686 |
sd->name); |
687 |
return SDEsupport; |
688 |
} |
689 |
/* get angle bases */ |
690 |
for (wld = ezxml_child(ezxml_child(wtl, "DataDefinition"), "AngleBasis"); |
691 |
wld != NULL; wld = wld->next) { |
692 |
rval = load_angle_basis(wld); |
693 |
if (rval < 0) |
694 |
return convert_errcode(rval); |
695 |
} |
696 |
/* load BSDF components */ |
697 |
for (wld = ezxml_child(wtl, "WavelengthData"); |
698 |
wld != NULL; wld = wld->next) { |
699 |
const char *cnm = ezxml_txt(ezxml_child(wld,"Wavelength")); |
700 |
int ct = -1; |
701 |
if (!strcasecmp(cnm, "Visible")) |
702 |
ct = mtx_Y; |
703 |
else if (!strcasecmp(cnm, "CIE-X")) |
704 |
ct = mtx_X; |
705 |
else if (!strcasecmp(cnm, "CIE-Z")) |
706 |
ct = mtx_Z; |
707 |
else |
708 |
continue; |
709 |
for (wdb = ezxml_child(wld, "WavelengthDataBlock"); |
710 |
wdb != NULL; wdb = wdb->next) |
711 |
if ((rval = load_bsdf_data(sd, wdb, ct, rowIn)) < 0) |
712 |
return convert_errcode(rval); |
713 |
} |
714 |
/* separate diffuse components */ |
715 |
sd->rf = extract_diffuse(&sd->rLambFront, sd->rf); |
716 |
sd->rb = extract_diffuse(&sd->rLambBack, sd->rb); |
717 |
sd->tf = extract_diffuse(&sd->tLambFront, sd->tf); |
718 |
if (sd->tb != NULL) { |
719 |
sd->tb = extract_diffuse(&sd->tLambBack, sd->tb); |
720 |
if (sd->tf == NULL) |
721 |
sd->tLambFront = sd->tLambBack; |
722 |
} else if (sd->tf != NULL) |
723 |
sd->tLambBack = sd->tLambFront; |
724 |
/* return success */ |
725 |
return SDEnone; |
726 |
} |
727 |
|
728 |
/* Get Matrix BSDF value */ |
729 |
static int |
730 |
SDgetMtxBSDF(float coef[SDmaxCh], const FVECT inVec, |
731 |
const FVECT outVec, SDComponent *sdc) |
732 |
{ |
733 |
const SDMat *dp; |
734 |
int i_ndx, o_ndx; |
735 |
/* check arguments */ |
736 |
if ((coef == NULL) | (outVec == NULL) | (inVec == NULL) | (sdc == NULL) |
737 |
|| (dp = (SDMat *)sdc->dist) == NULL) |
738 |
return 0; |
739 |
/* get angle indices */ |
740 |
i_ndx = mBSDF_incndx(dp, inVec); |
741 |
o_ndx = mBSDF_outndx(dp, outVec); |
742 |
/* try reciprocity if necessary */ |
743 |
if ((i_ndx < 0) & (o_ndx < 0)) { |
744 |
i_ndx = mBSDF_incndx(dp, outVec); |
745 |
o_ndx = mBSDF_outndx(dp, inVec); |
746 |
} |
747 |
if ((i_ndx < 0) | (o_ndx < 0)) |
748 |
return 0; /* nothing from this component */ |
749 |
|
750 |
return mBSDF_color(coef, dp, i_ndx, o_ndx); |
751 |
} |
752 |
|
753 |
/* Query solid angle for vector(s) */ |
754 |
static SDError |
755 |
SDqueryMtxProjSA(double *psa, const FVECT v1, const RREAL *v2, |
756 |
int qflags, SDComponent *sdc) |
757 |
{ |
758 |
const SDMat *dp; |
759 |
double inc_psa, out_psa; |
760 |
/* check arguments */ |
761 |
if ((psa == NULL) | (v1 == NULL) | (sdc == NULL) || |
762 |
(dp = (SDMat *)sdc->dist) == NULL) |
763 |
return SDEargument; |
764 |
if (v2 == NULL) |
765 |
v2 = v1; |
766 |
/* get projected solid angles */ |
767 |
out_psa = mBSDF_outohm(dp, mBSDF_outndx(dp, v1)); |
768 |
inc_psa = mBSDF_incohm(dp, mBSDF_incndx(dp, v2)); |
769 |
if ((v1 != v2) & (out_psa <= 0) & (inc_psa <= 0)) { |
770 |
inc_psa = mBSDF_outohm(dp, mBSDF_outndx(dp, v2)); |
771 |
out_psa = mBSDF_incohm(dp, mBSDF_incndx(dp, v1)); |
772 |
} |
773 |
|
774 |
switch (qflags) { /* record based on flag settings */ |
775 |
case SDqueryMax: |
776 |
if (inc_psa > psa[0]) |
777 |
psa[0] = inc_psa; |
778 |
if (out_psa > psa[0]) |
779 |
psa[0] = out_psa; |
780 |
break; |
781 |
case SDqueryMin+SDqueryMax: |
782 |
if (inc_psa > psa[1]) |
783 |
psa[1] = inc_psa; |
784 |
if (out_psa > psa[1]) |
785 |
psa[1] = out_psa; |
786 |
/* fall through */ |
787 |
case SDqueryVal: |
788 |
if (qflags == SDqueryVal) |
789 |
psa[0] = M_PI; |
790 |
/* fall through */ |
791 |
case SDqueryMin: |
792 |
if ((inc_psa > 0) & (inc_psa < psa[0])) |
793 |
psa[0] = inc_psa; |
794 |
if ((out_psa > 0) & (out_psa < psa[0])) |
795 |
psa[0] = out_psa; |
796 |
break; |
797 |
} |
798 |
/* make sure it's legal */ |
799 |
return (psa[0] <= 0) ? SDEinternal : SDEnone; |
800 |
} |
801 |
|
802 |
/* Compute new cumulative distribution from BSDF */ |
803 |
static int |
804 |
make_cdist(SDMatCDst *cd, const FVECT inVec, SDMat *dp, int rev) |
805 |
{ |
806 |
const unsigned maxval = ~0; |
807 |
double *cmtab, scale; |
808 |
int o; |
809 |
|
810 |
cmtab = (double *)malloc((cd->calen+1)*sizeof(double)); |
811 |
if (cmtab == NULL) |
812 |
return 0; |
813 |
cmtab[0] = .0; |
814 |
for (o = 0; o < cd->calen; o++) { |
815 |
if (rev) |
816 |
cmtab[o+1] = mBSDF_value(dp, cd->indx, o) * |
817 |
(*dp->ib_ohm)(o, dp->ib_priv); |
818 |
else |
819 |
cmtab[o+1] = mBSDF_value(dp, o, cd->indx) * |
820 |
(*dp->ob_ohm)(o, dp->ob_priv); |
821 |
cmtab[o+1] += cmtab[o]; |
822 |
} |
823 |
cd->cTotal = cmtab[cd->calen]; |
824 |
scale = (double)maxval / cd->cTotal; |
825 |
cd->carr[0] = 0; |
826 |
for (o = 1; o < cd->calen; o++) |
827 |
cd->carr[o] = scale*cmtab[o] + .5; |
828 |
cd->carr[cd->calen] = maxval; |
829 |
free(cmtab); |
830 |
return 1; |
831 |
} |
832 |
|
833 |
/* Get cumulative distribution for matrix BSDF */ |
834 |
static const SDCDst * |
835 |
SDgetMtxCDist(const FVECT inVec, SDComponent *sdc) |
836 |
{ |
837 |
SDMat *dp; |
838 |
int reverse; |
839 |
SDMatCDst myCD; |
840 |
SDMatCDst *cd, *cdlast; |
841 |
/* check arguments */ |
842 |
if ((inVec == NULL) | (sdc == NULL) || |
843 |
(dp = (SDMat *)sdc->dist) == NULL) |
844 |
return NULL; |
845 |
memset(&myCD, 0, sizeof(myCD)); |
846 |
myCD.indx = mBSDF_incndx(dp, inVec); |
847 |
if (myCD.indx >= 0) { |
848 |
myCD.ob_priv = dp->ob_priv; |
849 |
myCD.ob_vec = dp->ob_vec; |
850 |
myCD.calen = dp->nout; |
851 |
reverse = 0; |
852 |
} else { /* try reciprocity */ |
853 |
myCD.indx = mBSDF_outndx(dp, inVec); |
854 |
if (myCD.indx < 0) |
855 |
return NULL; |
856 |
myCD.ob_priv = dp->ib_priv; |
857 |
myCD.ob_vec = dp->ib_vec; |
858 |
myCD.calen = dp->ninc; |
859 |
reverse = 1; |
860 |
} |
861 |
cdlast = NULL; /* check for it in cache list */ |
862 |
/* PLACE MUTEX LOCK HERE FOR THREAD-SAFE */ |
863 |
for (cd = (SDMatCDst *)sdc->cdList; cd != NULL; |
864 |
cdlast = cd, cd = cd->next) |
865 |
if (cd->indx == myCD.indx && (cd->calen == myCD.calen) & |
866 |
(cd->ob_priv == myCD.ob_priv) & |
867 |
(cd->ob_vec == myCD.ob_vec)) |
868 |
break; |
869 |
if (cd == NULL) { /* need to allocate new entry */ |
870 |
cd = (SDMatCDst *)malloc(sizeof(SDMatCDst) + |
871 |
sizeof(myCD.carr[0])*myCD.calen); |
872 |
if (cd == NULL) |
873 |
return NULL; |
874 |
*cd = myCD; /* compute cumulative distribution */ |
875 |
if (!make_cdist(cd, inVec, dp, reverse)) { |
876 |
free(cd); |
877 |
return NULL; |
878 |
} |
879 |
cdlast = cd; |
880 |
} |
881 |
if (cdlast != NULL) { /* move entry to head of cache list */ |
882 |
cdlast->next = cd->next; |
883 |
cd->next = (SDMatCDst *)sdc->cdList; |
884 |
sdc->cdList = (SDCDst *)cd; |
885 |
} |
886 |
/* END MUTEX LOCK */ |
887 |
return (SDCDst *)cd; /* ready to go */ |
888 |
} |
889 |
|
890 |
/* Sample cumulative distribution */ |
891 |
static SDError |
892 |
SDsampMtxCDist(FVECT ioVec, double randX, const SDCDst *cdp) |
893 |
{ |
894 |
const unsigned maxval = ~0; |
895 |
const SDMatCDst *mcd = (const SDMatCDst *)cdp; |
896 |
const unsigned target = randX*maxval; |
897 |
int i, iupper, ilower; |
898 |
/* check arguments */ |
899 |
if ((ioVec == NULL) | (mcd == NULL)) |
900 |
return SDEargument; |
901 |
/* binary search to find index */ |
902 |
ilower = 0; iupper = mcd->calen; |
903 |
while ((i = (iupper + ilower) >> 1) != ilower) |
904 |
if (target >= mcd->carr[i]) |
905 |
ilower = i; |
906 |
else |
907 |
iupper = i; |
908 |
/* localize random position */ |
909 |
randX = (randX*maxval - mcd->carr[ilower]) / |
910 |
(double)(mcd->carr[iupper] - mcd->carr[ilower]); |
911 |
/* convert index to vector */ |
912 |
if ((*mcd->ob_vec)(ioVec, i+randX, mcd->ob_priv)) |
913 |
return SDEnone; |
914 |
strcpy(SDerrorDetail, "Matrix BSDF sampling fault"); |
915 |
return SDEinternal; |
916 |
} |
917 |
|
918 |
/* Fixed resolution BSDF methods */ |
919 |
const SDFunc SDhandleMtx = { |
920 |
&SDgetMtxBSDF, |
921 |
&SDqueryMtxProjSA, |
922 |
&SDgetMtxCDist, |
923 |
&SDsampMtxCDist, |
924 |
&SDfreeMatrix, |
925 |
}; |