1 |
– |
/* Copyright (c) 1991 Regents of the University of California */ |
2 |
– |
|
1 |
|
#ifndef lint |
2 |
< |
static char SCCSid[] = "$SunId$ LBL"; |
2 |
> |
static const char RCSid[] = "$Id$"; |
3 |
|
#endif |
6 |
– |
|
4 |
|
/* |
5 |
|
* Shading for materials with arbitrary BRDF's |
6 |
|
*/ |
7 |
|
|
8 |
+ |
#include "copyright.h" |
9 |
+ |
|
10 |
|
#include "ray.h" |
11 |
|
|
12 |
|
#include "data.h" |
20 |
|
* String arguments include the reflection function and files. |
21 |
|
* The BRDF is currently used just for the specular component to light |
22 |
|
* sources. Reflectance values or data coordinates are functions |
23 |
< |
* of the direction to the light source. |
23 |
> |
* of the direction to the light source. (Data modification functions |
24 |
> |
* are passed the source direction as args 2-4.) |
25 |
|
* We orient the surface towards the incoming ray, so a single |
26 |
|
* surface can be used to represent an infinitely thin object. |
27 |
|
* |
77 |
|
} BRDFDAT; /* BRDF material data */ |
78 |
|
|
79 |
|
|
80 |
+ |
static void |
81 |
|
dirbrdf(cval, np, ldir, omega) /* compute source contribution */ |
82 |
|
COLOR cval; /* returned coefficient */ |
83 |
|
register BRDFDAT *np; /* material data */ |
88 |
|
double dtmp; |
89 |
|
COLOR ctmp; |
90 |
|
FVECT ldx; |
91 |
< |
double lddx[3], pt[MAXDIM]; |
91 |
> |
static double vldx[5], pt[MAXDIM]; |
92 |
|
register char **sa; |
93 |
|
register int i; |
94 |
+ |
#define lddx (vldx+1) |
95 |
|
|
96 |
|
setcolor(cval, 0.0, 0.0, 0.0); |
97 |
|
|
132 |
|
multv3(ldx, ldir, funcxf.xfm); |
133 |
|
for (i = 0; i < 3; i++) |
134 |
|
lddx[i] = ldx[i]/funcxf.sca; |
135 |
+ |
lddx[3] = omega; |
136 |
|
/* compute BRTDF */ |
137 |
|
if (np->mp->otype == MAT_BRTDF) { |
138 |
|
if (sa[6][0] == '0') /* special case */ |
139 |
|
colval(ctmp,RED) = 0.0; |
140 |
|
else |
141 |
< |
colval(ctmp,RED) = funvalue(sa[6], 3, lddx); |
141 |
> |
colval(ctmp,RED) = funvalue(sa[6], 4, lddx); |
142 |
|
if (!strcmp(sa[7],sa[6])) |
143 |
|
colval(ctmp,GRN) = colval(ctmp,RED); |
144 |
|
else |
145 |
< |
colval(ctmp,GRN) = funvalue(sa[7], 3, lddx); |
145 |
> |
colval(ctmp,GRN) = funvalue(sa[7], 4, lddx); |
146 |
|
if (!strcmp(sa[8],sa[6])) |
147 |
|
colval(ctmp,BLU) = colval(ctmp,RED); |
148 |
|
else if (!strcmp(sa[8],sa[7])) |
149 |
|
colval(ctmp,BLU) = colval(ctmp,GRN); |
150 |
|
else |
151 |
< |
colval(ctmp,BLU) = funvalue(sa[8], 3, lddx); |
151 |
> |
colval(ctmp,BLU) = funvalue(sa[8], 4, lddx); |
152 |
|
dtmp = bright(ctmp); |
153 |
|
} else if (np->dp == NULL) { |
154 |
< |
dtmp = funvalue(sa[0], 3, lddx); |
154 |
> |
dtmp = funvalue(sa[0], 4, lddx); |
155 |
|
setcolor(ctmp, dtmp, dtmp, dtmp); |
156 |
|
} else { |
157 |
|
for (i = 0; i < np->dp->nd; i++) |
158 |
< |
pt[i] = funvalue(sa[3+i], 3, lddx); |
159 |
< |
dtmp = datavalue(np->dp, pt); |
160 |
< |
dtmp = funvalue(sa[0], 1, &dtmp); |
158 |
> |
pt[i] = funvalue(sa[3+i], 4, lddx); |
159 |
> |
vldx[0] = datavalue(np->dp, pt); |
160 |
> |
dtmp = funvalue(sa[0], 5, vldx); |
161 |
|
setcolor(ctmp, dtmp, dtmp, dtmp); |
162 |
|
} |
163 |
|
if (errno) { |
185 |
|
scalecolor(ctmp, dtmp); |
186 |
|
addcolor(cval, ctmp); |
187 |
|
} |
188 |
+ |
#undef lddx |
189 |
|
} |
190 |
|
|
191 |
|
|
192 |
< |
m_brdf(m, r) /* color a ray which hit a BRDTF material */ |
192 |
> |
int |
193 |
> |
m_brdf(m, r) /* color a ray that hit a BRDTfunc material */ |
194 |
|
register OBJREC *m; |
195 |
|
register RAY *r; |
196 |
|
{ |
197 |
+ |
int hitfront = 1; |
198 |
|
BRDFDAT nd; |
199 |
|
RAY sr; |
200 |
|
double transtest, transdist; |
201 |
|
int hasrefl, hastrans; |
202 |
|
COLOR ctmp; |
203 |
< |
double dtmp; |
203 |
> |
FVECT vtmp; |
204 |
|
register MFUNC *mf; |
205 |
|
register int i; |
206 |
|
/* check arguments */ |
224 |
|
setcolor(nd.tdiff, m->oargs.farg[6], |
225 |
|
m->oargs.farg[7], |
226 |
|
m->oargs.farg[8]); |
227 |
< |
/* get modifiers */ |
227 |
> |
/* get modifiers */ |
228 |
|
raytexture(r, m->omod); |
229 |
|
nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */ |
230 |
|
if (r->rod < 0.0) { /* orient perturbed values */ |
233 |
|
nd.pnorm[i] = -nd.pnorm[i]; |
234 |
|
r->pert[i] = -r->pert[i]; |
235 |
|
} |
236 |
+ |
hitfront = 0; |
237 |
|
} |
238 |
|
copycolor(nd.mcolor, r->pcol); /* get pattern color */ |
239 |
|
multcolor(nd.rdiff, nd.mcolor); /* modify diffuse values */ |
246 |
|
/* compute transmitted ray */ |
247 |
|
setbrdfunc(&nd); |
248 |
|
transtest = 0; |
249 |
+ |
transdist = r->rot; |
250 |
|
errno = 0; |
251 |
|
setcolor(ctmp, evalue(mf->ep[3]), |
252 |
|
evalue(mf->ep[4]), |
273 |
|
transdist = r->rot + sr.rt; |
274 |
|
} |
275 |
|
if (r->crtype & SHADOW) /* the rest is shadow */ |
276 |
< |
return; |
276 |
> |
return(1); |
277 |
|
/* compute reflected ray */ |
278 |
|
setbrdfunc(&nd); |
279 |
|
errno = 0; |
291 |
|
} |
292 |
|
/* compute ambient */ |
293 |
|
if (hasrefl) { |
294 |
< |
if (nd.pdot < 0.0) |
294 |
> |
if (!hitfront) |
295 |
|
flipsurface(r); |
296 |
< |
ambient(ctmp, r); |
296 |
> |
ambient(ctmp, r, nd.pnorm); |
297 |
|
multcolor(ctmp, nd.rdiff); |
298 |
|
addcolor(r->rcol, ctmp); /* add to returned color */ |
299 |
< |
if (nd.pdot < 0.0) |
299 |
> |
if (!hitfront) |
300 |
|
flipsurface(r); |
301 |
|
} |
302 |
|
if (hastrans) { /* from other side */ |
303 |
< |
if (nd.pdot > 0.0) |
303 |
> |
if (hitfront) |
304 |
|
flipsurface(r); |
305 |
< |
ambient(ctmp, r); |
305 |
> |
vtmp[0] = -nd.pnorm[0]; |
306 |
> |
vtmp[1] = -nd.pnorm[1]; |
307 |
> |
vtmp[2] = -nd.pnorm[2]; |
308 |
> |
ambient(ctmp, r, vtmp); |
309 |
|
multcolor(ctmp, nd.tdiff); |
310 |
|
addcolor(r->rcol, ctmp); |
311 |
< |
if (nd.pdot > 0.0) |
311 |
> |
if (hitfront) |
312 |
|
flipsurface(r); |
313 |
|
} |
314 |
|
if (hasrefl | hastrans || m->oargs.sarg[6][0] != '0') |
316 |
|
/* check distance */ |
317 |
|
if (transtest > bright(r->rcol)) |
318 |
|
r->rt = transdist; |
319 |
+ |
|
320 |
+ |
return(1); |
321 |
|
} |
322 |
|
|
323 |
|
|
324 |
|
|
325 |
< |
m_brdf2(m, r) /* color a ray which hit a BRDF material */ |
325 |
> |
int |
326 |
> |
m_brdf2(m, r) /* color a ray that hit a BRDF material */ |
327 |
|
register OBJREC *m; |
328 |
|
register RAY *r; |
329 |
|
{ |
330 |
|
BRDFDAT nd; |
331 |
|
COLOR ctmp; |
332 |
+ |
FVECT vtmp; |
333 |
|
double dtmp; |
334 |
|
/* always a shadow */ |
335 |
|
if (r->crtype & SHADOW) |
336 |
< |
return; |
336 |
> |
return(1); |
337 |
|
/* check arguments */ |
338 |
|
if (m->oargs.nsargs < (hasdata(m->otype)?4:2) | m->oargs.nfargs < |
339 |
|
(m->otype==MAT_TFUNC|m->otype==MAT_TDATA?6:4)) |
340 |
|
objerror(m, USER, "bad # arguments"); |
341 |
+ |
/* check for back side */ |
342 |
+ |
if (r->rod < 0.0) { |
343 |
+ |
if (!backvis && m->otype != MAT_TFUNC |
344 |
+ |
&& m->otype != MAT_TDATA) { |
345 |
+ |
raytrans(r); |
346 |
+ |
return(1); |
347 |
+ |
} |
348 |
+ |
raytexture(r, m->omod); |
349 |
+ |
flipsurface(r); /* reorient if backvis */ |
350 |
+ |
} else |
351 |
+ |
raytexture(r, m->omod); |
352 |
+ |
|
353 |
|
nd.mp = m; |
354 |
|
nd.pr = r; |
355 |
|
/* get material color */ |
371 |
|
/* compute reflectance */ |
372 |
|
dtmp = 1.0 - nd.trans - nd.rspec; |
373 |
|
setcolor(nd.rdiff, dtmp, dtmp, dtmp); |
347 |
– |
/* fix orientation */ |
348 |
– |
if (r->rod < 0.0) |
349 |
– |
flipsurface(r); |
350 |
– |
/* get modifiers */ |
351 |
– |
raytexture(r, m->omod); |
374 |
|
nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */ |
375 |
|
multcolor(nd.mcolor, r->pcol); /* modify material color */ |
376 |
|
multcolor(nd.rdiff, nd.mcolor); |
385 |
|
} |
386 |
|
/* compute ambient */ |
387 |
|
if (nd.trans < 1.0-FTINY) { |
388 |
< |
ambient(ctmp, r); |
388 |
> |
ambient(ctmp, r, nd.pnorm); |
389 |
|
scalecolor(ctmp, 1.0-nd.trans); |
390 |
|
multcolor(ctmp, nd.mcolor); /* modified by material color */ |
391 |
|
addcolor(r->rcol, ctmp); /* add to returned color */ |
392 |
|
} |
393 |
|
if (nd.trans > FTINY) { /* from other side */ |
394 |
|
flipsurface(r); |
395 |
< |
ambient(ctmp, r); |
395 |
> |
vtmp[0] = -nd.pnorm[0]; |
396 |
> |
vtmp[1] = -nd.pnorm[1]; |
397 |
> |
vtmp[2] = -nd.pnorm[2]; |
398 |
> |
ambient(ctmp, r, vtmp); |
399 |
|
scalecolor(ctmp, nd.trans); |
400 |
|
multcolor(ctmp, nd.mcolor); |
401 |
|
addcolor(r->rcol, ctmp); |
403 |
|
} |
404 |
|
/* add direct component */ |
405 |
|
direct(r, dirbrdf, &nd); |
406 |
+ |
|
407 |
+ |
return(1); |
408 |
|
} |
409 |
|
|
410 |
|
|
411 |
+ |
int |
412 |
|
setbrdfunc(np) /* set up brdf function and variables */ |
413 |
|
register BRDFDAT *np; |
414 |
|
{ |