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 */ |