7 |
|
/* |
8 |
|
* Compute Glare Index given by program name: |
9 |
|
* |
10 |
< |
* gnuth_dgr - Gnuth discomfort glare rating |
11 |
< |
* gnuth_vcp - Gnuth visual comfort probability |
10 |
> |
* guth_dgr - Guth discomfort glare rating |
11 |
> |
* guth_vcp - Guth visual comfort probability |
12 |
> |
* cie_cgi - CIE Glare Index (1983) |
13 |
|
* |
14 |
|
* 12 April 1991 Greg Ward EPFL |
15 |
|
*/ |
22 |
|
double posindex(); |
23 |
|
int headline(); |
24 |
|
|
25 |
< |
double direct(), gnuth_dgr(), gnuth_vcp(); |
25 |
> |
double direct(), guth_dgr(), guth_vcp(), cie_cgi(); |
26 |
|
|
27 |
|
struct named_func { |
28 |
|
char *name; |
29 |
|
double (*func)(); |
30 |
|
} all_funcs[] = { |
31 |
|
{"direct", direct}, |
32 |
< |
{"gnuth_dgr", gnuth_dgr}, |
33 |
< |
{"gnuth_vcp", gnuth_vcp}, |
32 |
> |
{"guth_dgr", guth_dgr}, |
33 |
> |
{"guth_vcp", guth_vcp}, |
34 |
> |
{"cie_cgi", cie_cgi}, |
35 |
|
{NULL} |
36 |
|
}; |
37 |
|
|
55 |
|
|
56 |
|
VIEW midview = STDVIEW; |
57 |
|
|
58 |
+ |
int wrongformat = 0; |
59 |
|
|
60 |
+ |
|
61 |
|
main(argc, argv) |
62 |
|
int argc; |
63 |
|
char *argv[]; |
93 |
|
exit(1); |
94 |
|
} |
95 |
|
/* read header */ |
96 |
< |
getheader(stdin, headline); |
96 |
> |
getheader(stdin, headline, NULL); |
97 |
> |
if (wrongformat) { |
98 |
> |
fprintf(stderr, "%s: bad input format\n", progname); |
99 |
> |
exit(1); |
100 |
> |
} |
101 |
|
if (print_header) { /* add to header */ |
102 |
|
printargs(i, argv, stdout); |
103 |
|
putchar('\n'); |
104 |
|
} |
105 |
|
/* set view */ |
106 |
|
if (setview(&midview) != NULL) { |
107 |
< |
fprintf(stderr, "%s: bad view information in input\n"); |
107 |
> |
fprintf(stderr, "%s: bad view information in input\n", |
108 |
> |
progname); |
109 |
|
exit(1); |
110 |
|
} |
111 |
|
/* get findglare data */ |
128 |
|
headline(s) /* get line from header */ |
129 |
|
char *s; |
130 |
|
{ |
131 |
+ |
char fmt[32]; |
132 |
+ |
|
133 |
|
if (print_header) /* copy to output */ |
134 |
|
fputs(s, stdout); |
135 |
|
if (!strncmp(s, VIEWSTR, VIEWSTRL)) |
136 |
|
sscanview(&midview, s+VIEWSTRL); |
137 |
+ |
else if (isformat(s)) { |
138 |
+ |
formatval(fmt, s); |
139 |
+ |
wrongformat = strcmp(fmt, "ascii"); |
140 |
+ |
} |
141 |
|
} |
142 |
|
|
143 |
|
|
170 |
|
&gs->dir[0], &gs->dir[1], &gs->dir[2], |
171 |
|
&gs->dom, &gs->lum) != 5) |
172 |
|
goto readerr; |
173 |
+ |
normalize(gs->dir); |
174 |
|
gs->next = all_srcs; |
175 |
|
all_srcs = gs; |
176 |
|
break; |
241 |
|
* All vectors are assumed to be normalized. |
242 |
|
* This function is an implementation of the method proposed by |
243 |
|
* Robert Levin in his 1975 JIES article. |
244 |
+ |
* This calculation presumes the view direction and up vectors perpendicular. |
245 |
|
* We return a value less than zero for improper positions. |
246 |
|
*/ |
247 |
|
|
255 |
|
d = DOT(sd,vd); |
256 |
|
if (d <= 0.0) |
257 |
|
return(-1.0); |
258 |
+ |
if (d >= 1.0) |
259 |
+ |
return(1.0); |
260 |
|
sigma = acos(d) * (180./PI); |
261 |
< |
tau = acos(DOT(sd,vu)/sqrt(1.0-d*d)) * (180./PI); |
261 |
> |
d = DOT(sd,vu)/sqrt(1.0-d*d); |
262 |
> |
if (d >= 1.0) |
263 |
> |
tau = 0.0; |
264 |
> |
else |
265 |
> |
tau = acos(d) * (180./PI); |
266 |
|
return( exp( sigma*( (35.2 - tau*.31889 - 1.22*exp(-.22222*tau))*1e-3 |
267 |
|
+ sigma*(21. + tau*(.26667 + tau*-.002963))*1e-5 ) |
268 |
|
) ); |
270 |
|
|
271 |
|
|
272 |
|
double |
273 |
< |
gnuth_dgr(gd) /* compute Gnuth discomfort glare rating */ |
273 |
> |
guth_dgr(gd) /* compute Guth discomfort glare rating */ |
274 |
|
struct glare_dir *gd; |
275 |
|
{ |
276 |
|
#define q(w) (20.4*w+1.52*pow(w,.2)-.075) |
277 |
|
register struct glare_src *gs; |
278 |
+ |
FVECT mydir; |
279 |
|
double p; |
280 |
|
double sum; |
281 |
+ |
double wtot, brsum; |
282 |
|
int n; |
283 |
|
|
284 |
< |
sum = 0.0; n = 0; |
284 |
> |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
285 |
> |
sum = wtot = brsum = 0.0; n = 0; |
286 |
|
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
287 |
< |
p = posindex(gs->dir, midview.vdir, midview.vup); |
287 |
> |
p = posindex(gs->dir, mydir, midview.vup); |
288 |
|
if (p <= FTINY) |
289 |
|
continue; |
290 |
|
sum += gs->lum * q(gs->dom) / p; |
291 |
+ |
brsum += gs->lum * gs->dom; |
292 |
+ |
wtot += gs->dom; |
293 |
|
n++; |
294 |
|
} |
295 |
|
if (n == 0) |
296 |
|
return(0.0); |
297 |
< |
else |
298 |
< |
return( pow( |
271 |
< |
.5*sum/pow(direct(gd)+gd->indirect,.44), |
297 |
> |
|
298 |
> |
return( pow(.5*sum/pow((brsum+(5.-wtot)*gd->indirect/PI)/5.,.44), |
299 |
|
pow((double)n, -.0914) ) ); |
300 |
|
#undef q |
301 |
|
} |
311 |
|
|
312 |
|
|
313 |
|
double |
314 |
< |
gnuth_vcp(gd) /* compute Gnuth visual comfort probability */ |
314 |
> |
guth_vcp(gd) /* compute Guth visual comfort probability */ |
315 |
|
struct glare_dir *gd; |
316 |
|
{ |
317 |
< |
return(100.*norm_integral(-6.374+1.3227*log(gnuth_dgr(gd)))); |
317 |
> |
double dgr; |
318 |
> |
|
319 |
> |
dgr = guth_dgr(gd); |
320 |
> |
if (dgr <= FTINY) |
321 |
> |
return(100.0); |
322 |
> |
return(100.*norm_integral(6.374-1.3227*log(dgr))); |
323 |
> |
} |
324 |
> |
|
325 |
> |
|
326 |
> |
double |
327 |
> |
cie_cgi(gd) /* compute CIE Glare Index */ |
328 |
> |
struct glare_dir *gd; |
329 |
> |
{ |
330 |
> |
register struct glare_src *gs; |
331 |
> |
FVECT mydir; |
332 |
> |
double dillum; |
333 |
> |
double p; |
334 |
> |
double sum; |
335 |
> |
|
336 |
> |
spinvector(mydir, midview.vdir, midview.vup, gd->ang); |
337 |
> |
sum = 0.0; |
338 |
> |
for (gs = all_srcs; gs != NULL; gs = gs->next) { |
339 |
> |
p = posindex(gs->dir, mydir, midview.vup); |
340 |
> |
if (p <= FTINY) |
341 |
> |
continue; |
342 |
> |
sum += gs->lum*gs->lum * gs->dom / (p*p); |
343 |
> |
} |
344 |
> |
if (sum <= FTINY) |
345 |
> |
return(0.0); |
346 |
> |
dillum = direct(gd); |
347 |
> |
return(8.*log10(2.*sum*(1.+dillum/500.)/(dillum+gd->indirect))); |
348 |
|
} |