105 |
|
theta = PI/180.0/2.0 * so->oargs.farg[3]; |
106 |
|
if (theta <= FTINY) |
107 |
|
objerror(so, USER, "zero size"); |
108 |
< |
src->ss = theta >= PI/4 ? 1.0 : tan(theta); |
108 |
> |
src->ss = theta >= PI/4.0 ? 1.0 : tan(theta); |
109 |
|
src->ss2 = 2.0*PI * (1.0 - cos(theta)); |
110 |
|
} |
111 |
|
|
150 |
|
makespot(m) /* make a spotlight */ |
151 |
|
register OBJREC *m; |
152 |
|
{ |
153 |
– |
extern double cos(); |
153 |
|
register SPOT *ns; |
154 |
|
|
155 |
|
if ((ns = (SPOT *)malloc(sizeof(SPOT))) == NULL) |
168 |
|
OBJREC *op; |
169 |
|
{ |
170 |
|
double maxrad2; |
171 |
< |
double d2; |
171 |
> |
double d; |
172 |
|
register int i, j; |
173 |
|
register FACE *f; |
174 |
|
|
175 |
|
f = getface(op); |
176 |
+ |
if (f->area == 0.) |
177 |
+ |
return(0.); |
178 |
|
for (i = 0; i < 3; i++) { |
179 |
|
ocent[i] = 0.; |
180 |
|
for (j = 0; j < f->nv; j++) |
181 |
|
ocent[i] += VERTEX(f,j)[i]; |
182 |
|
ocent[i] /= (double)f->nv; |
183 |
|
} |
184 |
+ |
d = DOT(ocent,f->norm); |
185 |
+ |
for (i = 0; i < 3; i++) |
186 |
+ |
ocent[i] += (f->offset - d)*f->norm[i]; |
187 |
|
maxrad2 = 0.; |
188 |
|
for (j = 0; j < f->nv; j++) { |
189 |
< |
d2 = dist2(VERTEX(f,j), ocent); |
190 |
< |
if (d2 > maxrad2) |
191 |
< |
maxrad2 = d2; |
189 |
> |
d = dist2(VERTEX(f,j), ocent); |
190 |
> |
if (d > maxrad2) |
191 |
> |
maxrad2 = d; |
192 |
|
} |
193 |
|
return(maxrad2); |
194 |
|
} |
230 |
|
co = getcone(op, 0); |
231 |
|
VCOPY(nvec, co->ad); |
232 |
|
return(DOT(nvec, CO_P0(co))); |
233 |
+ |
} |
234 |
+ |
|
235 |
+ |
|
236 |
+ |
commonspot(sp1, sp2, org) /* set sp1 to intersection of sp1 and sp2 */ |
237 |
+ |
register SPOT *sp1, *sp2; |
238 |
+ |
FVECT org; |
239 |
+ |
{ |
240 |
+ |
FVECT cent; |
241 |
+ |
double rad2, cos1, cos2; |
242 |
+ |
|
243 |
+ |
cos1 = 1. - sp1->siz/(2.*PI); |
244 |
+ |
cos2 = 1. - sp2->siz/(2.*PI); |
245 |
+ |
if (sp2->siz >= 2.*PI-FTINY) /* BIG, just check overlap */ |
246 |
+ |
return(DOT(sp1->aim,sp2->aim) >= cos1*cos2 - |
247 |
+ |
sqrt((1.-cos1*cos1)*(1.-cos2*cos2))); |
248 |
+ |
/* compute and check disks */ |
249 |
+ |
rad2 = intercircle(cent, sp1->aim, sp2->aim, |
250 |
+ |
1./(cos1*cos1) - 1., 1./(cos2*cos2) - 1.); |
251 |
+ |
if (rad2 <= FTINY || normalize(cent) == 0.) |
252 |
+ |
return(0); |
253 |
+ |
VCOPY(sp1->aim, cent); |
254 |
+ |
sp1->siz = 2.*PI*(1. - 1./sqrt(1.+rad2)); |
255 |
+ |
return(1); |
256 |
+ |
} |
257 |
+ |
|
258 |
+ |
|
259 |
+ |
commonbeam(sp1, sp2, dir) /* set sp1 to intersection of sp1 and sp2 */ |
260 |
+ |
register SPOT *sp1, *sp2; |
261 |
+ |
FVECT dir; |
262 |
+ |
{ |
263 |
+ |
FVECT cent, c1, c2; |
264 |
+ |
double rad2, d; |
265 |
+ |
register int i; |
266 |
+ |
/* move centers to common plane */ |
267 |
+ |
d = DOT(sp1->aim, dir); |
268 |
+ |
for (i = 0; i < 3; i++) |
269 |
+ |
c1[i] = sp1->aim[i] - d*dir[i]; |
270 |
+ |
d = DOT(sp2->aim, dir); |
271 |
+ |
for (i = 0; i < 3; i++) |
272 |
+ |
c2[i] = sp2->aim[i] - d*dir[i]; |
273 |
+ |
/* compute overlap */ |
274 |
+ |
rad2 = intercircle(cent, c1, c2, sp1->siz/PI, sp2->siz/PI); |
275 |
+ |
if (rad2 <= FTINY) |
276 |
+ |
return(0); |
277 |
+ |
VCOPY(sp1->aim, cent); |
278 |
+ |
sp1->siz = PI*rad2; |
279 |
+ |
return(1); |
280 |
+ |
} |
281 |
+ |
|
282 |
+ |
|
283 |
+ |
checkspot(sp, nrm) /* check spotlight for behind source */ |
284 |
+ |
register SPOT *sp; /* spotlight */ |
285 |
+ |
FVECT nrm; /* source surface normal */ |
286 |
+ |
{ |
287 |
+ |
double d, d1; |
288 |
+ |
|
289 |
+ |
d = DOT(sp->aim, nrm); |
290 |
+ |
if (d > FTINY) /* center in front? */ |
291 |
+ |
return(0); |
292 |
+ |
/* else check horizon */ |
293 |
+ |
d1 = 1. - sp->siz/(2.*PI); |
294 |
+ |
return(1.-FTINY-d*d > d1*d1); |
295 |
+ |
} |
296 |
+ |
|
297 |
+ |
|
298 |
+ |
double |
299 |
+ |
spotdisk(oc, op, sp, pos) /* intersect spot with object op */ |
300 |
+ |
FVECT oc; |
301 |
+ |
OBJREC *op; |
302 |
+ |
register SPOT *sp; |
303 |
+ |
FVECT pos; |
304 |
+ |
{ |
305 |
+ |
FVECT onorm; |
306 |
+ |
double offs, d, dist; |
307 |
+ |
register int i; |
308 |
+ |
|
309 |
+ |
offs = getplaneq(onorm, op); |
310 |
+ |
d = -DOT(onorm, sp->aim); |
311 |
+ |
if (d >= -FTINY && d <= FTINY) |
312 |
+ |
return(0.); |
313 |
+ |
dist = (DOT(pos, onorm) - offs)/d; |
314 |
+ |
if (dist < 0.) |
315 |
+ |
return(0.); |
316 |
+ |
for (i = 0; i < 3; i++) |
317 |
+ |
oc[i] = pos[i] + dist*sp->aim[i]; |
318 |
+ |
return(sp->siz*dist*dist/PI/(d*d)); |
319 |
+ |
} |
320 |
+ |
|
321 |
+ |
|
322 |
+ |
double |
323 |
+ |
beamdisk(oc, op, sp, dir) /* intersect beam with object op */ |
324 |
+ |
FVECT oc; |
325 |
+ |
OBJREC *op; |
326 |
+ |
register SPOT *sp; |
327 |
+ |
FVECT dir; |
328 |
+ |
{ |
329 |
+ |
FVECT onorm; |
330 |
+ |
double offs, d, dist; |
331 |
+ |
register int i; |
332 |
+ |
|
333 |
+ |
offs = getplaneq(onorm, op); |
334 |
+ |
d = -DOT(onorm, dir); |
335 |
+ |
if (d >= -FTINY && d <= FTINY) |
336 |
+ |
return(0.); |
337 |
+ |
dist = (DOT(sp->aim, onorm) - offs)/d; |
338 |
+ |
for (i = 0; i < 3; i++) |
339 |
+ |
oc[i] = sp->aim[i] + dist*dir[i]; |
340 |
+ |
return(sp->siz/PI/(d*d)); |
341 |
+ |
} |
342 |
+ |
|
343 |
+ |
|
344 |
+ |
double |
345 |
+ |
intercircle(cc, c1, c2, r1s, r2s) /* intersect two circles */ |
346 |
+ |
FVECT cc; /* midpoint (return value) */ |
347 |
+ |
FVECT c1, c2; /* circle centers */ |
348 |
+ |
double r1s, r2s; /* radii squared */ |
349 |
+ |
{ |
350 |
+ |
double a2, d2, l; |
351 |
+ |
FVECT disp; |
352 |
+ |
register int i; |
353 |
+ |
|
354 |
+ |
for (i = 0; i < 3; i++) |
355 |
+ |
disp[i] = c2[i] - c1[i]; |
356 |
+ |
d2 = DOT(disp,disp); |
357 |
+ |
/* circle within overlap? */ |
358 |
+ |
if (r1s < r2s) { |
359 |
+ |
if (r2s >= r1s + d2) { |
360 |
+ |
VCOPY(cc, c1); |
361 |
+ |
return(r1s); |
362 |
+ |
} |
363 |
+ |
} else { |
364 |
+ |
if (r1s >= r2s + d2) { |
365 |
+ |
VCOPY(cc, c2); |
366 |
+ |
return(r2s); |
367 |
+ |
} |
368 |
+ |
} |
369 |
+ |
a2 = .25*(2.*(r1s+r2s) - d2 - (r2s-r1s)*(r2s-r1s)/d2); |
370 |
+ |
/* no overlap? */ |
371 |
+ |
if (a2 <= 0.) |
372 |
+ |
return(0.); |
373 |
+ |
/* overlap, compute center */ |
374 |
+ |
l = sqrt((r1s - a2)/d2); |
375 |
+ |
for (i = 0; i < 3; i++) |
376 |
+ |
cc[i] = c1[i] + l*disp[i]; |
377 |
+ |
return(a2); |
378 |
|
} |
379 |
|
|
380 |
|
|