1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: mkillum2.c,v 2.37 2011/08/16 18:09:53 greg Exp $"; |
3 |
#endif |
4 |
/* |
5 |
* Routines to do the actual calculation for mkillum |
6 |
*/ |
7 |
|
8 |
#include <string.h> |
9 |
|
10 |
#include "mkillum.h" |
11 |
#include "face.h" |
12 |
#include "cone.h" |
13 |
#include "source.h" |
14 |
#include "paths.h" |
15 |
|
16 |
#ifndef NBSDFSAMPS |
17 |
#define NBSDFSAMPS 256 /* BSDF resampling count */ |
18 |
#endif |
19 |
|
20 |
COLORV * distarr = NULL; /* distribution array */ |
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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; |
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} |
36 |
if (distsiz < siz) { |
37 |
if (distsiz > 0) |
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free(distarr); |
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distarr = (COLORV *)malloc(sizeof(COLOR)*siz); |
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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); |
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} |
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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 |
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) |
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{ |
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COLORV *colp; |
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|
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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) |
61 |
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); |
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return(1); |
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} |
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|
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|
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void |
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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; |
77 |
int rv; |
78 |
|
79 |
if ((ndx < 0) | (ndx >= distsiz)) |
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error(INTERNAL, "bad index in raysamp"); |
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VCOPY(myRay.rorg, org); |
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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)) |
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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; |
140 |
|
141 |
while (process_ray(&myRay, ray_presult(&myRay, 0))) |
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; |
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} |
144 |
|
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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, |
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FVECT n |
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) |
152 |
{ |
153 |
register int i; |
154 |
|
155 |
v[0] = v[1] = v[2] = 0.0; |
156 |
for (i = 0; i < 3; i++) |
157 |
if (n[i] < 0.6 && n[i] > -0.6) |
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break; |
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v[i] = 1.0; |
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fcross(u, v, n); |
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normalize(u); |
162 |
fcross(v, n, u); |
163 |
} |
164 |
|
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|
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static void |
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rounddir( /* compute uniform spherical direction */ |
168 |
register FVECT dv, |
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double alt, |
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double azi |
171 |
) |
172 |
{ |
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double d1, d2; |
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|
175 |
dv[2] = 1. - 2.*alt; |
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d1 = sqrt(1. - dv[2]*dv[2]); |
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d2 = 2.*PI * azi; |
178 |
dv[0] = d1*cos(d2); |
179 |
dv[1] = d1*sin(d2); |
180 |
} |
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|
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|
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void |
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flatdir( /* compute uniform hemispherical direction */ |
185 |
FVECT dv, |
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double alt, |
187 |
double azi |
188 |
) |
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{ |
190 |
double d1, d2; |
191 |
|
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d1 = sqrt(alt); |
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d2 = 2.*PI * azi; |
194 |
dv[0] = d1*cos(d2); |
195 |
dv[1] = d1*sin(d2); |
196 |
dv[2] = sqrt(1. - alt); |
197 |
} |
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|
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|
200 |
int |
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flatindex( /* compute index for hemispherical direction */ |
202 |
FVECT dv, |
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int nalt, |
204 |
int nazi |
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) |
206 |
{ |
207 |
double d; |
208 |
int i, j; |
209 |
|
210 |
d = 1.0 - dv[2]*dv[2]; |
211 |
i = d*nalt; |
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d = atan2(dv[1], dv[0]) * (0.5/PI); |
213 |
if (d < 0.0) d += 1.0; |
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j = d*nazi + 0.5; |
215 |
if (j >= nazi) j = 0; |
216 |
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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) |
226 |
{ |
227 |
sprintf(errmsg, "(%s): cannot make illum for %s \"%s\"", |
228 |
nm, ofun[ob->otype].funame, ob->oname); |
229 |
error(WARNING, errmsg); |
230 |
printobj(il->altmat, ob); |
231 |
return(1); |
232 |
} |
233 |
|
234 |
|
235 |
int |
236 |
my_face( /* make an illum face */ |
237 |
OBJREC *ob, |
238 |
struct illum_args *il, |
239 |
char *nm |
240 |
) |
241 |
{ |
242 |
int dim[2]; |
243 |
int n, nalt, nazi, alti; |
244 |
double sp[2], r1, r2; |
245 |
int h; |
246 |
FVECT dn, org, dir; |
247 |
FVECT u, v; |
248 |
double ur[2], vr[2]; |
249 |
MAT4 xfm; |
250 |
char xfrot[64]; |
251 |
int nallow; |
252 |
FACE *fa; |
253 |
int i, j; |
254 |
/* get/check arguments */ |
255 |
fa = getface(ob); |
256 |
if (fa->area == 0.0) { |
257 |
freeface(ob); |
258 |
return(my_default(ob, il, nm)); |
259 |
} |
260 |
/* set up sampling */ |
261 |
if (il->sampdens <= 0) { |
262 |
nalt = nazi = 1; /* diffuse assumption */ |
263 |
} else { |
264 |
n = PI * il->sampdens; |
265 |
nalt = sqrt(n/PI) + .5; |
266 |
nazi = PI*nalt + .5; |
267 |
} |
268 |
n = nazi*nalt; |
269 |
newdist(n); |
270 |
/* take first edge >= sqrt(area) */ |
271 |
for (j = fa->nv-1, i = 0; i < fa->nv; j = i++) { |
272 |
u[0] = VERTEX(fa,i)[0] - VERTEX(fa,j)[0]; |
273 |
u[1] = VERTEX(fa,i)[1] - VERTEX(fa,j)[1]; |
274 |
u[2] = VERTEX(fa,i)[2] - VERTEX(fa,j)[2]; |
275 |
if ((r1 = DOT(u,u)) >= fa->area-FTINY) |
276 |
break; |
277 |
} |
278 |
if (i < fa->nv) { /* got one! -- let's align our axes */ |
279 |
r2 = 1.0/sqrt(r1); |
280 |
u[0] *= r2; u[1] *= r2; u[2] *= r2; |
281 |
fcross(v, fa->norm, u); |
282 |
} else /* oh well, we'll just have to wing it */ |
283 |
mkaxes(u, v, fa->norm); |
284 |
/* now, find limits in (u,v) coordinates */ |
285 |
ur[0] = vr[0] = FHUGE; |
286 |
ur[1] = vr[1] = -FHUGE; |
287 |
for (i = 0; i < fa->nv; i++) { |
288 |
r1 = DOT(VERTEX(fa,i),u); |
289 |
if (r1 < ur[0]) ur[0] = r1; |
290 |
if (r1 > ur[1]) ur[1] = r1; |
291 |
r2 = DOT(VERTEX(fa,i),v); |
292 |
if (r2 < vr[0]) vr[0] = r2; |
293 |
if (r2 > vr[1]) vr[1] = r2; |
294 |
} |
295 |
dim[0] = random(); |
296 |
/* sample polygon */ |
297 |
nallow = 5*n*il->nsamps; |
298 |
for (dim[1] = 0; dim[1] < n; dim[1]++) |
299 |
for (i = 0; i < il->nsamps; i++) { |
300 |
/* randomize direction */ |
301 |
h = ilhash(dim, 2) + i; |
302 |
multisamp(sp, 2, urand(h)); |
303 |
alti = dim[1]/nazi; |
304 |
r1 = (alti + sp[0])/nalt; |
305 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi; |
306 |
flatdir(dn, r1, r2); |
307 |
for (j = 0; j < 3; j++) |
308 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - |
309 |
dn[2]*fa->norm[j]; |
310 |
/* randomize location */ |
311 |
do { |
312 |
multisamp(sp, 2, urand(h+4862+nallow)); |
313 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
314 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
315 |
for (j = 0; j < 3; j++) |
316 |
org[j] = r1*u[j] + r2*v[j] |
317 |
+ fa->offset*fa->norm[j]; |
318 |
} while (!inface(org, fa) && nallow-- > 0); |
319 |
if (nallow < 0) { |
320 |
objerror(ob, WARNING, "bad aspect"); |
321 |
rayclean(); |
322 |
freeface(ob); |
323 |
return(my_default(ob, il, nm)); |
324 |
} |
325 |
r1 = 5.*FTINY; |
326 |
for (j = 0; j < 3; j++) |
327 |
org[j] += r1*fa->norm[j]; |
328 |
/* send sample */ |
329 |
raysamp(dim[1], org, dir); |
330 |
} |
331 |
/* add in direct component? */ |
332 |
if (il->flags & IL_LIGHT) { |
333 |
MAT4 ixfm; |
334 |
for (i = 3; i--; ) { |
335 |
ixfm[i][0] = u[i]; |
336 |
ixfm[i][1] = v[i]; |
337 |
ixfm[i][2] = fa->norm[i]; |
338 |
ixfm[i][3] = 0.; |
339 |
} |
340 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.; |
341 |
ixfm[3][3] = 1.; |
342 |
dim[0] = random(); |
343 |
nallow = 10*il->nsamps; |
344 |
for (i = 0; i < il->nsamps; i++) { |
345 |
/* randomize location */ |
346 |
h = dim[0] + samplendx++; |
347 |
do { |
348 |
multisamp(sp, 2, urand(h+nallow)); |
349 |
r1 = ur[0] + (ur[1]-ur[0]) * sp[0]; |
350 |
r2 = vr[0] + (vr[1]-vr[0]) * sp[1]; |
351 |
for (j = 0; j < 3; j++) |
352 |
org[j] = r1*u[j] + r2*v[j] |
353 |
+ fa->offset*fa->norm[j]; |
354 |
} while (!inface(org, fa) && nallow-- > 0); |
355 |
if (nallow < 0) { |
356 |
objerror(ob, WARNING, "bad aspect"); |
357 |
rayclean(); |
358 |
freeface(ob); |
359 |
return(my_default(ob, il, nm)); |
360 |
} |
361 |
/* sample source rays */ |
362 |
srcsamps(il, org, fa->norm, ixfm); |
363 |
} |
364 |
} |
365 |
/* wait for all rays to finish */ |
366 |
rayclean(); |
367 |
/* write out the face and its distribution */ |
368 |
if (average(il, distarr, n)) { |
369 |
if (il->sampdens > 0) |
370 |
flatout(il, distarr, nalt, nazi, u, v, fa->norm); |
371 |
illumout(il, ob); |
372 |
} else |
373 |
printobj(il->altmat, ob); |
374 |
/* clean up */ |
375 |
freeface(ob); |
376 |
return(0); |
377 |
} |
378 |
|
379 |
|
380 |
int |
381 |
my_sphere( /* make an illum sphere */ |
382 |
register OBJREC *ob, |
383 |
struct illum_args *il, |
384 |
char *nm |
385 |
) |
386 |
{ |
387 |
int dim[3]; |
388 |
int n, nalt, nazi; |
389 |
double sp[4], r1, r2, r3; |
390 |
FVECT org, dir; |
391 |
FVECT u, v; |
392 |
register int i, j; |
393 |
/* check arguments */ |
394 |
if (ob->oargs.nfargs != 4) |
395 |
objerror(ob, USER, "bad # of arguments"); |
396 |
/* set up sampling */ |
397 |
if (il->sampdens <= 0) |
398 |
nalt = nazi = 1; |
399 |
else { |
400 |
n = 4.*PI * il->sampdens; |
401 |
nalt = sqrt(2./PI*n) + .5; |
402 |
nazi = PI/2.*nalt + .5; |
403 |
} |
404 |
n = nalt*nazi; |
405 |
newdist(n); |
406 |
dim[0] = random(); |
407 |
/* sample sphere */ |
408 |
for (dim[1] = 0; dim[1] < nalt; dim[1]++) |
409 |
for (dim[2] = 0; dim[2] < nazi; dim[2]++) |
410 |
for (i = 0; i < il->nsamps; i++) { |
411 |
/* next sample point */ |
412 |
multisamp(sp, 4, urand(ilhash(dim,3)+i)); |
413 |
/* random direction */ |
414 |
r1 = (dim[1] + sp[0])/nalt; |
415 |
r2 = (dim[2] + sp[1] - .5)/nazi; |
416 |
rounddir(dir, r1, r2); |
417 |
/* random location */ |
418 |
mkaxes(u, v, dir); /* yuck! */ |
419 |
r3 = sqrt(sp[2]); |
420 |
r2 = 2.*PI*sp[3]; |
421 |
r1 = r3*ob->oargs.farg[3]*cos(r2); |
422 |
r2 = r3*ob->oargs.farg[3]*sin(r2); |
423 |
r3 = ob->oargs.farg[3]*sqrt(1.01-r3*r3); |
424 |
for (j = 0; j < 3; j++) { |
425 |
org[j] = ob->oargs.farg[j] + r1*u[j] + r2*v[j] + |
426 |
r3*dir[j]; |
427 |
dir[j] = -dir[j]; |
428 |
} |
429 |
/* send sample */ |
430 |
raysamp(dim[1]*nazi+dim[2], org, dir); |
431 |
} |
432 |
/* wait for all rays to finish */ |
433 |
rayclean(); |
434 |
/* write out the sphere and its distribution */ |
435 |
if (average(il, distarr, n)) { |
436 |
if (il->sampdens > 0) |
437 |
roundout(il, distarr, nalt, nazi); |
438 |
else |
439 |
objerror(ob, WARNING, "diffuse distribution"); |
440 |
illumout(il, ob); |
441 |
} else |
442 |
printobj(il->altmat, ob); |
443 |
/* clean up */ |
444 |
return(1); |
445 |
} |
446 |
|
447 |
|
448 |
int |
449 |
my_ring( /* make an illum ring */ |
450 |
OBJREC *ob, |
451 |
struct illum_args *il, |
452 |
char *nm |
453 |
) |
454 |
{ |
455 |
int dim[2]; |
456 |
int n, nalt, nazi, alti; |
457 |
double sp[2], r1, r2, r3; |
458 |
int h; |
459 |
FVECT dn, org, dir; |
460 |
FVECT u, v; |
461 |
MAT4 xfm; |
462 |
CONE *co; |
463 |
int i, j; |
464 |
/* get/check arguments */ |
465 |
co = getcone(ob, 0); |
466 |
/* set up sampling */ |
467 |
if (il->sampdens <= 0) { |
468 |
nalt = nazi = 1; /* diffuse assumption */ |
469 |
} else { |
470 |
n = PI * il->sampdens; |
471 |
nalt = sqrt(n/PI) + .5; |
472 |
nazi = PI*nalt + .5; |
473 |
} |
474 |
n = nazi*nalt; |
475 |
newdist(n); |
476 |
mkaxes(u, v, co->ad); |
477 |
dim[0] = random(); |
478 |
/* sample disk */ |
479 |
for (dim[1] = 0; dim[1] < n; dim[1]++) |
480 |
for (i = 0; i < il->nsamps; i++) { |
481 |
/* next sample point */ |
482 |
h = ilhash(dim,2) + i; |
483 |
/* randomize direction */ |
484 |
multisamp(sp, 2, urand(h)); |
485 |
alti = dim[1]/nazi; |
486 |
r1 = (alti + sp[0])/nalt; |
487 |
r2 = (dim[1] - alti*nazi + sp[1] - .5)/nazi; |
488 |
flatdir(dn, r1, r2); |
489 |
for (j = 0; j < 3; j++) |
490 |
dir[j] = -dn[0]*u[j] - dn[1]*v[j] - dn[2]*co->ad[j]; |
491 |
/* randomize location */ |
492 |
multisamp(sp, 2, urand(h+8371)); |
493 |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
494 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
495 |
r2 = 2.*PI*sp[1]; |
496 |
r1 = r3*cos(r2); |
497 |
r2 = r3*sin(r2); |
498 |
r3 = 5.*FTINY; |
499 |
for (j = 0; j < 3; j++) |
500 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j] + |
501 |
r3*co->ad[j]; |
502 |
/* send sample */ |
503 |
raysamp(dim[1], org, dir); |
504 |
} |
505 |
/* add in direct component? */ |
506 |
if (il->flags & IL_LIGHT) { |
507 |
MAT4 ixfm; |
508 |
for (i = 3; i--; ) { |
509 |
ixfm[i][0] = u[i]; |
510 |
ixfm[i][1] = v[i]; |
511 |
ixfm[i][2] = co->ad[i]; |
512 |
ixfm[i][3] = 0.; |
513 |
} |
514 |
ixfm[3][0] = ixfm[3][1] = ixfm[3][2] = 0.; |
515 |
ixfm[3][3] = 1.; |
516 |
dim[0] = random(); |
517 |
for (i = 0; i < il->nsamps; i++) { |
518 |
/* randomize location */ |
519 |
h = dim[0] + samplendx++; |
520 |
multisamp(sp, 2, urand(h)); |
521 |
r3 = sqrt(CO_R0(co)*CO_R0(co) + |
522 |
sp[0]*(CO_R1(co)*CO_R1(co) - CO_R0(co)*CO_R0(co))); |
523 |
r2 = 2.*PI*sp[1]; |
524 |
r1 = r3*cos(r2); |
525 |
r2 = r3*sin(r2); |
526 |
for (j = 0; j < 3; j++) |
527 |
org[j] = CO_P0(co)[j] + r1*u[j] + r2*v[j]; |
528 |
/* sample source rays */ |
529 |
srcsamps(il, org, co->ad, ixfm); |
530 |
} |
531 |
} |
532 |
/* wait for all rays to finish */ |
533 |
rayclean(); |
534 |
/* write out the ring and its distribution */ |
535 |
if (average(il, distarr, n)) { |
536 |
if (il->sampdens > 0) |
537 |
flatout(il, distarr, nalt, nazi, u, v, co->ad); |
538 |
illumout(il, ob); |
539 |
} else |
540 |
printobj(il->altmat, ob); |
541 |
/* clean up */ |
542 |
freecone(ob); |
543 |
return(1); |
544 |
} |