1 |
– |
/* Copyright (c) 1996 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 |
|
* normal.c - shading function for normal materials. |
6 |
|
* |
11 |
|
* Later changes described in delta comments. |
12 |
|
*/ |
13 |
|
|
14 |
< |
#include "ray.h" |
14 |
> |
#include "copyright.h" |
15 |
|
|
16 |
+ |
#include "ray.h" |
17 |
+ |
#include "ambient.h" |
18 |
+ |
#include "source.h" |
19 |
|
#include "otypes.h" |
20 |
< |
|
20 |
> |
#include "rtotypes.h" |
21 |
|
#include "random.h" |
22 |
|
|
23 |
– |
extern double specthresh; /* specular sampling threshold */ |
24 |
– |
extern double specjitter; /* specular sampling jitter */ |
25 |
– |
|
26 |
– |
extern int backvis; /* back faces visible? */ |
27 |
– |
|
23 |
|
#ifndef MAXITER |
24 |
|
#define MAXITER 10 /* maximum # specular ray attempts */ |
25 |
|
#endif |
26 |
+ |
/* estimate of Fresnel function */ |
27 |
+ |
#define FRESNE(ci) (exp(-5.85*(ci)) - 0.00287989916) |
28 |
|
|
32 |
– |
static gaussamp(); |
29 |
|
|
30 |
|
/* |
31 |
|
* This routine implements the isotropic Gaussian |
64 |
|
double pdot; /* perturbed dot product */ |
65 |
|
} NORMDAT; /* normal material data */ |
66 |
|
|
67 |
+ |
static srcdirf_t dirnorm; |
68 |
+ |
static void gaussamp(RAY *r, NORMDAT *np); |
69 |
|
|
70 |
< |
dirnorm(cval, np, ldir, omega) /* compute source contribution */ |
71 |
< |
COLOR cval; /* returned coefficient */ |
72 |
< |
register NORMDAT *np; /* material data */ |
73 |
< |
FVECT ldir; /* light source direction */ |
74 |
< |
double omega; /* light source size */ |
70 |
> |
|
71 |
> |
static void |
72 |
> |
dirnorm( /* compute source contribution */ |
73 |
> |
COLOR cval, /* returned coefficient */ |
74 |
> |
void *nnp, /* material data */ |
75 |
> |
FVECT ldir, /* light source direction */ |
76 |
> |
double omega /* light source size */ |
77 |
> |
) |
78 |
|
{ |
79 |
+ |
register NORMDAT *np = nnp; |
80 |
|
double ldot; |
81 |
+ |
double ldiff; |
82 |
|
double dtmp, d2; |
83 |
|
FVECT vtmp; |
84 |
|
COLOR ctmp; |
90 |
|
if (ldot < 0.0 ? np->trans <= FTINY : np->trans >= 1.0-FTINY) |
91 |
|
return; /* wrong side */ |
92 |
|
|
93 |
< |
if (ldot > FTINY && np->rdiff > FTINY) { |
93 |
> |
/* Fresnel estimate */ |
94 |
> |
ldiff = np->rdiff; |
95 |
> |
if (np->specfl & SP_PURE && (np->rspec > FTINY) & (ldiff > FTINY)) |
96 |
> |
ldiff *= 1. - FRESNE(fabs(ldot)); |
97 |
> |
|
98 |
> |
if (ldot > FTINY && ldiff > FTINY) { |
99 |
|
/* |
100 |
|
* Compute and add diffuse reflected component to returned |
101 |
|
* color. The diffuse reflected component will always be |
102 |
|
* modified by the color of the material. |
103 |
|
*/ |
104 |
|
copycolor(ctmp, np->mcolor); |
105 |
< |
dtmp = ldot * omega * np->rdiff / PI; |
105 |
> |
dtmp = ldot * omega * ldiff / PI; |
106 |
|
scalecolor(ctmp, dtmp); |
107 |
|
addcolor(cval, ctmp); |
108 |
|
} |
162 |
|
} |
163 |
|
|
164 |
|
|
165 |
< |
m_normal(m, r) /* color a ray that hit something normal */ |
166 |
< |
register OBJREC *m; |
167 |
< |
register RAY *r; |
165 |
> |
extern int |
166 |
> |
m_normal( /* color a ray that hit something normal */ |
167 |
> |
register OBJREC *m, |
168 |
> |
register RAY *r |
169 |
> |
) |
170 |
|
{ |
171 |
|
NORMDAT nd; |
172 |
+ |
double fest; |
173 |
|
double transtest, transdist; |
174 |
|
double mirtest, mirdist; |
175 |
|
int hastexture; |
188 |
|
raytrans(r); |
189 |
|
return(1); |
190 |
|
} |
191 |
+ |
raytexture(r, m->omod); |
192 |
|
flipsurface(r); /* reorient if backvis */ |
193 |
< |
} |
193 |
> |
} else |
194 |
> |
raytexture(r, m->omod); |
195 |
|
nd.mp = m; |
196 |
|
nd.rp = r; |
197 |
|
/* get material color */ |
203 |
|
nd.alpha2 = m->oargs.farg[4]; |
204 |
|
if ((nd.alpha2 *= nd.alpha2) <= FTINY) |
205 |
|
nd.specfl |= SP_PURE; |
206 |
< |
if (r->ro != NULL && isflat(r->ro->otype)) |
207 |
< |
nd.specfl |= SP_FLAT; |
195 |
< |
/* get modifiers */ |
196 |
< |
raytexture(r, m->omod); |
197 |
< |
if (hastexture = DOT(r->pert,r->pert) > FTINY*FTINY) |
206 |
> |
|
207 |
> |
if ( (hastexture = (DOT(r->pert,r->pert) > FTINY*FTINY)) ) { |
208 |
|
nd.pdot = raynormal(nd.pnorm, r); /* perturb normal */ |
209 |
< |
else { |
209 |
> |
} else { |
210 |
|
VCOPY(nd.pnorm, r->ron); |
211 |
|
nd.pdot = r->rod; |
212 |
|
} |
213 |
+ |
if (r->ro != NULL && isflat(r->ro->otype)) |
214 |
+ |
nd.specfl |= SP_FLAT; |
215 |
|
if (nd.pdot < .001) |
216 |
|
nd.pdot = .001; /* non-zero for dirnorm() */ |
217 |
|
multcolor(nd.mcolor, r->pcol); /* modify material color */ |
218 |
|
mirtest = transtest = 0; |
219 |
|
mirdist = transdist = r->rot; |
220 |
|
nd.rspec = m->oargs.farg[3]; |
221 |
+ |
/* compute Fresnel approx. */ |
222 |
+ |
if (nd.specfl & SP_PURE && nd.rspec > FTINY) { |
223 |
+ |
fest = FRESNE(r->rod); |
224 |
+ |
nd.rspec += fest*(1. - nd.rspec); |
225 |
+ |
} else |
226 |
+ |
fest = 0.; |
227 |
|
/* compute transmission */ |
228 |
|
if (m->otype == MAT_TRANS) { |
229 |
|
nd.trans = m->oargs.farg[5]*(1.0 - nd.rspec); |
272 |
|
if (nd.rspec > FTINY) { |
273 |
|
nd.specfl |= SP_REFL; |
274 |
|
/* compute specular color */ |
275 |
< |
if (m->otype == MAT_METAL) |
275 |
> |
if (m->otype != MAT_METAL) { |
276 |
> |
setcolor(nd.scolor, nd.rspec, nd.rspec, nd.rspec); |
277 |
> |
} else if (fest > FTINY) { |
278 |
> |
d = nd.rspec*(1. - fest); |
279 |
> |
for (i = 0; i < 3; i++) |
280 |
> |
nd.scolor[i] = fest + nd.mcolor[i]*d; |
281 |
> |
} else { |
282 |
|
copycolor(nd.scolor, nd.mcolor); |
283 |
< |
else |
284 |
< |
setcolor(nd.scolor, 1.0, 1.0, 1.0); |
261 |
< |
scalecolor(nd.scolor, nd.rspec); |
283 |
> |
scalecolor(nd.scolor, nd.rspec); |
284 |
> |
} |
285 |
|
/* check threshold */ |
286 |
|
if (!(nd.specfl & SP_PURE) && specthresh >= nd.rspec-FTINY) |
287 |
|
nd.specfl |= SP_RBLT; |
356 |
|
} |
357 |
|
|
358 |
|
|
359 |
< |
static |
360 |
< |
gaussamp(r, np) /* sample gaussian specular */ |
361 |
< |
RAY *r; |
362 |
< |
register NORMDAT *np; |
359 |
> |
static void |
360 |
> |
gaussamp( /* sample gaussian specular */ |
361 |
> |
RAY *r, |
362 |
> |
register NORMDAT *np |
363 |
> |
) |
364 |
|
{ |
365 |
|
RAY sr; |
366 |
|
FVECT u, v, h; |
392 |
|
d = urand(ilhash(dimlist,ndims)+samplendx); |
393 |
|
multisamp(rv, 2, d); |
394 |
|
d = 2.0*PI * rv[0]; |
395 |
< |
cosp = cos(d); |
396 |
< |
sinp = sin(d); |
395 |
> |
cosp = tcos(d); |
396 |
> |
sinp = tsin(d); |
397 |
|
rv[1] = 1.0 - specjitter*rv[1]; |
398 |
|
if (rv[1] <= FTINY) |
399 |
|
d = 1.0; |
424 |
|
d = urand(ilhash(dimlist,ndims)+1823+samplendx); |
425 |
|
multisamp(rv, 2, d); |
426 |
|
d = 2.0*PI * rv[0]; |
427 |
< |
cosp = cos(d); |
428 |
< |
sinp = sin(d); |
427 |
> |
cosp = tcos(d); |
428 |
> |
sinp = tsin(d); |
429 |
|
rv[1] = 1.0 - specjitter*rv[1]; |
430 |
|
if (rv[1] <= FTINY) |
431 |
|
d = 1.0; |
432 |
|
else |
433 |
< |
d = sqrt( -log(rv[1]) * np->alpha2 ); |
433 |
> |
d = sqrt( np->alpha2 * -log(rv[1]) ); |
434 |
|
for (i = 0; i < 3; i++) |
435 |
|
sr.rdir[i] = np->prdir[i] + d*(cosp*u[i] + sinp*v[i]); |
436 |
|
if (DOT(sr.rdir, r->ron) < -FTINY) { |