1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: mkillum2.c,v 2.39 2014/12/04 05:26:28 greg Exp $"; |
3 |
#endif |
4 |
/* |
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* Routines to do the actual calculation for mkillum |
6 |
*/ |
7 |
|
8 |
#include <string.h> |
9 |
|
10 |
#include "mkillum.h" |
11 |
#include "face.h" |
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#include "cone.h" |
13 |
#include "source.h" |
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#include "paths.h" |
15 |
|
16 |
#ifndef NBSDFSAMPS |
17 |
#define NBSDFSAMPS 256 /* BSDF resampling count */ |
18 |
#endif |
19 |
|
20 |
COLORV * distarr = NULL; /* distribution array */ |
21 |
int distsiz = 0; |
22 |
|
23 |
|
24 |
void |
25 |
newdist( /* allocate & clear distribution array */ |
26 |
int siz |
27 |
) |
28 |
{ |
29 |
if (siz <= 0) { |
30 |
if (distsiz > 0) |
31 |
free(distarr); |
32 |
distarr = NULL; |
33 |
distsiz = 0; |
34 |
return; |
35 |
} |
36 |
if (distsiz < siz) { |
37 |
if (distsiz > 0) |
38 |
free(distarr); |
39 |
distarr = (COLORV *)malloc(sizeof(COLOR)*siz); |
40 |
if (distarr == NULL) |
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error(SYSTEM, "out of memory in newdist"); |
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distsiz = siz; |
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} |
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memset(distarr, '\0', sizeof(COLOR)*siz); |
45 |
} |
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|
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|
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int |
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process_ray( /* process a ray result or report error */ |
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RAY *r, |
51 |
int rv |
52 |
) |
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{ |
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COLORV *colp; |
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|
56 |
if (rv == 0) /* no result ready */ |
57 |
return(0); |
58 |
if (rv < 0) |
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error(USER, "ray tracing process died"); |
60 |
if (r->rno >= distsiz) |
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error(INTERNAL, "bad returned index in process_ray"); |
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multcolor(r->rcol, r->rcoef); /* in case it's a source ray */ |
63 |
colp = &distarr[r->rno * 3]; |
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addcolor(colp, r->rcol); |
65 |
return(1); |
66 |
} |
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|
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|
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void |
70 |
raysamp( /* queue a ray sample */ |
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int ndx, |
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FVECT org, |
73 |
FVECT dir |
74 |
) |
75 |
{ |
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RAY myRay; |
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int rv; |
78 |
|
79 |
if ((ndx < 0) | (ndx >= distsiz)) |
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error(INTERNAL, "bad index in raysamp"); |
81 |
VCOPY(myRay.rorg, org); |
82 |
VCOPY(myRay.rdir, dir); |
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myRay.rmax = .0; |
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rayorigin(&myRay, PRIMARY|SPECULAR, NULL, NULL); |
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myRay.rno = ndx; |
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/* queue ray, check result */ |
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process_ray(&myRay, ray_pqueue(&myRay)); |
88 |
} |
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|
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|
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void |
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srcsamps( /* sample sources from this surface position */ |
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struct illum_args *il, |
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FVECT org, |
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FVECT nrm, |
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MAT4 ixfm |
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) |
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{ |
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int nalt=1, nazi=1; |
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SRCINDEX si; |
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RAY sr; |
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FVECT v; |
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double d; |
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int i, j; |
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/* get sampling density */ |
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if (il->sampdens > 0) { |
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i = PI * il->sampdens; |
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nalt = sqrt(i/PI) + .5; |
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nazi = PI*nalt + .5; |
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} |
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initsrcindex(&si); /* loop over (sub)sources */ |
112 |
for ( ; ; ) { |
113 |
VCOPY(sr.rorg, org); /* pick side to shoot from */ |
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d = 5.*FTINY; |
115 |
VSUM(sr.rorg, sr.rorg, nrm, d); |
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samplendx++; /* increment sample counter */ |
117 |
if (!srcray(&sr, NULL, &si)) |
118 |
break; /* end of sources */ |
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/* index direction */ |
120 |
if (ixfm != NULL) |
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multv3(v, sr.rdir, ixfm); |
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else |
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VCOPY(v, sr.rdir); |
124 |
if (v[2] >= -FTINY) |
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continue; /* only sample transmission */ |
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v[0] = -v[0]; v[1] = -v[1]; v[2] = -v[2]; |
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sr.rno = flatindex(v, nalt, nazi); |
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d = nalt*nazi*(1./PI) * v[2]; |
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d *= si.dom; /* solid angle correction */ |
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scalecolor(sr.rcoef, d); |
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process_ray(&sr, ray_pqueue(&sr)); |
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} |
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} |
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|
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|
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void |
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rayclean() /* finish all pending rays */ |
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{ |
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RAY myRay; |
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|
141 |
while (process_ray(&myRay, ray_presult(&myRay, 0))) |
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; |
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} |
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|
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|
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static void |
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mkaxes( /* compute u and v to go with n */ |
148 |
FVECT u, |
149 |
FVECT v, |
150 |
FVECT n |
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) |
152 |
{ |
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getperpendicular(u, n, 1); |
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fcross(v, n, u); |
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} |
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|
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|
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static void |
159 |
rounddir( /* compute uniform spherical direction */ |
160 |
FVECT dv, |
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double alt, |
162 |
double azi |
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) |
164 |
{ |
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double d1, d2; |
166 |
|
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dv[2] = 1. - 2.*alt; |
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d1 = sqrt(1. - dv[2]*dv[2]); |
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d2 = 2.*PI * azi; |
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dv[0] = d1*cos(d2); |
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dv[1] = d1*sin(d2); |
172 |
} |
173 |
|
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|
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void |
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flatdir( /* compute uniform hemispherical direction */ |
177 |
FVECT dv, |
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double alt, |
179 |
double azi |
180 |
) |
181 |
{ |
182 |
double d1, d2; |
183 |
|
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d1 = sqrt(alt); |
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d2 = 2.*PI * azi; |
186 |
dv[0] = d1*cos(d2); |
187 |
dv[1] = d1*sin(d2); |
188 |
dv[2] = sqrt(1. - alt); |
189 |
} |
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|
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|
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int |
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flatindex( /* compute index for hemispherical direction */ |
194 |
FVECT dv, |
195 |
int nalt, |
196 |
int nazi |
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) |
198 |
{ |
199 |
double d; |
200 |
int i, j; |
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|
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d = 1.0 - dv[2]*dv[2]; |
203 |
i = d*nalt; |
204 |
d = atan2(dv[1], dv[0]) * (0.5/PI); |
205 |
if (d < 0.0) d += 1.0; |
206 |
j = d*nazi + 0.5; |
207 |
if (j >= nazi) j = 0; |
208 |
return(i*nazi + j); |
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} |
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|
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|
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int |
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my_default( /* default illum action */ |
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OBJREC *ob, |
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struct illum_args *il, |
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char *nm |
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) |
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{ |
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sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"", |
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nm, ofun[ob->otype].funame, ob->oname); |
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error(WARNING, errmsg); |
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printobj(il->altmat, ob); |
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return(1); |
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} |
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|
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|
227 |
int |
228 |
my_face( /* make an illum face */ |
229 |
OBJREC *ob, |
230 |
struct illum_args *il, |
231 |
char *nm |
232 |
) |
233 |
{ |
234 |
int dim[2]; |
235 |
int n, nalt, nazi, alti; |
236 |
double sp[2], r1, r2; |
237 |
int h; |
238 |
FVECT dn, org, dir; |
239 |
FVECT u, v; |
240 |
double ur[2], vr[2]; |
241 |
MAT4 xfm; |
242 |
char xfrot[64]; |
243 |
int nallow; |
244 |
FACE *fa; |
245 |
int i, j; |
246 |
/* get/check arguments */ |
247 |
fa = getface(ob); |
248 |
if (fa->area == 0.0) { |
249 |
freeface(ob); |
250 |
return(my_default(ob, il, nm)); |
251 |
} |
252 |
/* set up sampling */ |
253 |
if (il->sampdens <= 0) { |
254 |
nalt = nazi = 1; /* diffuse assumption */ |
255 |
} else { |
256 |
n = PI * il->sampdens; |
257 |
nalt = sqrt(n/PI) + .5; |
258 |
nazi = PI*nalt + .5; |
259 |
} |
260 |
n = nazi*nalt; |
261 |
newdist(n); |
262 |
/* take first edge >= sqrt(area) */ |
263 |
for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) { |
264 |
u[0] = VERTEX(fa,i)[0] - VERTEX(fa,j)[0]; |
265 |
u[1] = VERTEX(fa,i)[1] - VERTEX(fa,j)[1]; |
266 |
u[2] = VERTEX(fa,i)[2] - VERTEX(fa,j)[2]; |
267 |
if ((r1 = DOT(u,u)) >= fa->area-FTINY) |
268 |
break; |
269 |
} |
270 |
if (i < fa->nv) { /* got one! -- let's align our axes */ |
271 |
r2 = 1.0/sqrt(r1); |
272 |
u[0] *= r2; u[1] *= r2; u[2] *= r2; |
273 |
fcross(v, fa->norm, u); |
274 |
} else /* oh well, we'll just have to wing it */ |
275 |
mkaxes(u, v, fa->norm); |
276 |
/* now, find limits in (u,v) coordinates */ |
277 |
ur[0] = vr[0] = FHUGE; |
278 |
ur[1] = vr[1] = -FHUGE; |
279 |
for (i = 0; i < fa->nv; i++) { |
280 |
r1 = DOT(VERTEX(fa,i),u); |
281 |
if (r1 < ur[0]) ur[0] = r1; |
282 |
if (r1 > ur[1]) ur[1] = r1; |
283 |
r2 = DOT(VERTEX(fa,i),v); |
284 |
if (r2 < vr[0]) vr[0] = r2; |
285 |
if (r2 > vr[1]) vr[1] = r2; |
286 |
} |
287 |
dim[0] = random(); |
288 |
/* sample polygon */ |
289 |
nallow = 5*n*il->nsamps; |
290 |
for (dim[1] = 0; dim[1] < n; dim[1]++) |
291 |
for (i = 0; i < il->nsamps; i++) { |
292 |
/* randomize direction */ |
293 |
h = ilhash(dim, 2) + i; |
294 |
multisamp(sp, 2, urand(h)); |
295 |
alti = dim[1]/nazi; |
296 |
r1 = (alti + sp[0])/nalt; |
297 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi; |
298 |
flatdir(dn, r1, r2); |
299 |
for (j = 0; j < 3; j++) |
300 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - |
301 |
dn[2]*fa->norm[j]; |
302 |
/* randomize location */ |
303 |
do { |
304 |
multisamp(sp, 2, urand(h+4862+nallow)); |
305 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
306 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
307 |
for (j = 0; j < 3; j++) |
308 |
org[j] = r1*u[j] + r2*v[j] |
309 |
+ fa->offset*fa->norm[j]; |
310 |
} while (!inface(org, fa) && nallow-- > 0); |
311 |
if (nallow < 0) { |
312 |
objerror(ob, WARNING, "bad aspect"); |
313 |
rayclean(); |
314 |
freeface(ob); |
315 |
return(my_default(ob, il, nm)); |
316 |
} |
317 |
r1 = 5.*FTINY; |
318 |
for (j = 0; j < 3; j++) |
319 |
org[j] += r1*fa->norm[j]; |
320 |
/* send sample */ |
321 |
raysamp(dim[1], org, dir); |
322 |
} |
323 |
/* add in direct component? */ |
324 |
if (il->flags & IL_LIGHT) { |
325 |
MAT4 ixfm; |
326 |
for (i = 3; i--; ) { |
327 |
ixfm[i][0] = u[i]; |
328 |
ixfm[i][1] = v[i]; |
329 |
ixfm[i][2] = fa->norm[i]; |
330 |
ixfm[i][3] = 0.; |
331 |
} |
332 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.; |
333 |
ixfm[3][3] = 1.; |
334 |
dim[0] = random(); |
335 |
nallow = 10*il->nsamps; |
336 |
for (i = 0; i < il->nsamps; i++) { |
337 |
/* randomize location */ |
338 |
h = dim[0] + samplendx++; |
339 |
do { |
340 |
multisamp(sp, 2, urand(h+nallow)); |
341 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
342 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
343 |
for (j = 0; j < 3; j++) |
344 |
org[j] = r1*u[j] + r2*v[j] |
345 |
+ fa->offset*fa->norm[j]; |
346 |
} while (!inface(org, fa) && nallow-- > 0); |
347 |
if (nallow < 0) { |
348 |
objerror(ob, WARNING, "bad aspect"); |
349 |
rayclean(); |
350 |
freeface(ob); |
351 |
return(my_default(ob, il, nm)); |
352 |
} |
353 |
/* sample source rays */ |
354 |
srcsamps(il, org, fa->norm, ixfm); |
355 |
} |
356 |
} |
357 |
/* wait for all rays to finish */ |
358 |
rayclean(); |
359 |
/* write out the face and its distribution */ |
360 |
if (average(il, distarr, n)) { |
361 |
if (il->sampdens > 0) |
362 |
flatout(il, distarr, nalt, nazi, u, v, fa->norm); |
363 |
illumout(il, ob); |
364 |
} else |
365 |
printobj(il->altmat, ob); |
366 |
/* clean up */ |
367 |
freeface(ob); |
368 |
return(0); |
369 |
} |
370 |
|
371 |
|
372 |
int |
373 |
my_sphere( /* make an illum sphere */ |
374 |
OBJREC *ob, |
375 |
struct illum_args *il, |
376 |
char *nm |
377 |
) |
378 |
{ |
379 |
int dim[3]; |
380 |
int n, nalt, nazi; |
381 |
double sp[4], r1, r2, r3; |
382 |
FVECT org, dir; |
383 |
FVECT u, v; |
384 |
int i, j; |
385 |
/* check arguments */ |
386 |
if (ob->oargs.nfargs != 4) |
387 |
objerror(ob, USER, "bad # of arguments"); |
388 |
/* set up sampling */ |
389 |
if (il->sampdens <= 0) |
390 |
nalt = nazi = 1; |
391 |
else { |
392 |
n = 4.*PI * il->sampdens; |
393 |
nalt = sqrt(2./PI*n) + .5; |
394 |
nazi = PI/2.*nalt + .5; |
395 |
} |
396 |
n = nalt*nazi; |
397 |
newdist(n); |
398 |
dim[0] = random(); |
399 |
/* sample sphere */ |
400 |
for (dim[1] = 0; dim[1] < nalt; dim[1]++) |
401 |
for (dim[2] = 0; dim[2] < nazi; dim[2]++) |
402 |
for (i = 0; i < il->nsamps; i++) { |
403 |
/* next sample point */ |
404 |
multisamp(sp, 4, urand(ilhash(dim,3)+i)); |
405 |
/* random direction */ |
406 |
r1 = (dim[1] + sp[0])/nalt; |
407 |
r2 = (dim[2] + sp[1] - .5)/nazi; |
408 |
rounddir(dir, r1, r2); |
409 |
/* random location */ |
410 |
mkaxes(u, v, dir); /* yuck! */ |
411 |
r3 = sqrt(sp[2]); |
412 |
r2 = 2.*PI*sp[3]; |
413 |
r1 = r3*ob->oargs.farg[3]*cos(r2); |
414 |
r2 = r3*ob->oargs.farg[3]*sin(r2); |
415 |
r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3); |
416 |
for (j = 0; j < 3; j++) { |
417 |
org[j] = ob->oargs.farg[j] + r1*u[j] + r2*v[j] + |
418 |
r3*dir[j]; |
419 |
dir[j] = -dir[j]; |
420 |
} |
421 |
/* send sample */ |
422 |
raysamp(dim[1]*nazi+dim[2], org, dir); |
423 |
} |
424 |
/* wait for all rays to finish */ |
425 |
rayclean(); |
426 |
/* write out the sphere and its distribution */ |
427 |
if (average(il, distarr, n)) { |
428 |
if (il->sampdens > 0) |
429 |
roundout(il, distarr, nalt, nazi); |
430 |
else |
431 |
objerror(ob, WARNING, "diffuse distribution"); |
432 |
illumout(il, ob); |
433 |
} else |
434 |
printobj(il->altmat, ob); |
435 |
/* clean up */ |
436 |
return(1); |
437 |
} |
438 |
|
439 |
|
440 |
int |
441 |
my_ring( /* make an illum ring */ |
442 |
OBJREC *ob, |
443 |
struct illum_args *il, |
444 |
char *nm |
445 |
) |
446 |
{ |
447 |
int dim[2]; |
448 |
int n, nalt, nazi, alti; |
449 |
double sp[2], r1, r2, r3; |
450 |
int h; |
451 |
FVECT dn, org, dir; |
452 |
FVECT u, v; |
453 |
MAT4 xfm; |
454 |
CONE *co; |
455 |
int i, j; |
456 |
/* get/check arguments */ |
457 |
co = getcone(ob, 0); |
458 |
/* set up sampling */ |
459 |
if (il->sampdens <= 0) { |
460 |
nalt = nazi = 1; /* diffuse assumption */ |
461 |
} else { |
462 |
n = PI * il->sampdens; |
463 |
nalt = sqrt(n/PI) + .5; |
464 |
nazi = PI*nalt + .5; |
465 |
} |
466 |
n = nazi*nalt; |
467 |
newdist(n); |
468 |
mkaxes(u, v, co->ad); |
469 |
dim[0] = random(); |
470 |
/* sample disk */ |
471 |
for (dim[1] = 0; dim[1] < n; dim[1]++) |
472 |
for (i = 0; i < il->nsamps; i++) { |
473 |
/* next sample point */ |
474 |
h = ilhash(dim,2) + i; |
475 |
/* randomize direction */ |
476 |
multisamp(sp, 2, urand(h)); |
477 |
alti = dim[1]/nazi; |
478 |
r1 = (alti + sp[0])/nalt; |
479 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi; |
480 |
flatdir(dn, r1, r2); |
481 |
for (j = 0; j < 3; j++) |
482 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j]; |
483 |
/* randomize location */ |
484 |
multisamp(sp, 2, urand(h+8371)); |
485 |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
486 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
487 |
r2 = 2.*PI*sp[1]; |
488 |
r1 = r3*cos(r2); |
489 |
r2 = r3*sin(r2); |
490 |
r3 = 5.*FTINY; |
491 |
for (j = 0; j < 3; j++) |
492 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] + |
493 |
r3*co->ad[j]; |
494 |
/* send sample */ |
495 |
raysamp(dim[1], org, dir); |
496 |
} |
497 |
/* add in direct component? */ |
498 |
if (il->flags & IL_LIGHT) { |
499 |
MAT4 ixfm; |
500 |
for (i = 3; i--; ) { |
501 |
ixfm[i][0] = u[i]; |
502 |
ixfm[i][1] = v[i]; |
503 |
ixfm[i][2] = co->ad[i]; |
504 |
ixfm[i][3] = 0.; |
505 |
} |
506 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.; |
507 |
ixfm[3][3] = 1.; |
508 |
dim[0] = random(); |
509 |
for (i = 0; i < il->nsamps; i++) { |
510 |
/* randomize location */ |
511 |
h = dim[0] + samplendx++; |
512 |
multisamp(sp, 2, urand(h)); |
513 |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
514 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
515 |
r2 = 2.*PI*sp[1]; |
516 |
r1 = r3*cos(r2); |
517 |
r2 = r3*sin(r2); |
518 |
for (j = 0; j < 3; j++) |
519 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j]; |
520 |
/* sample source rays */ |
521 |
srcsamps(il, org, co->ad, ixfm); |
522 |
} |
523 |
} |
524 |
/* wait for all rays to finish */ |
525 |
rayclean(); |
526 |
/* write out the ring and its distribution */ |
527 |
if (average(il, distarr, n)) { |
528 |
if (il->sampdens > 0) |
529 |
flatout(il, distarr, nalt, nazi, u, v, co->ad); |
530 |
illumout(il, ob); |
531 |
} else |
532 |
printobj(il->altmat, ob); |
533 |
/* clean up */ |
534 |
freecone(ob); |
535 |
return(1); |
536 |
} |