26 |
|
|
27 |
|
#define DOT(v1,v2) (v1[0]*v2[0]+v1[1]*v2[1]+v1[2]*v2[2]) |
28 |
|
|
29 |
+ |
#define S_CLEAR 1 |
30 |
+ |
#define S_OVER 2 |
31 |
+ |
#define S_UNIF 3 |
32 |
+ |
#define S_INTER 4 |
33 |
+ |
|
34 |
+ |
#define overcast (skytype==S_OVER|skytype==S_UNIF) |
35 |
+ |
|
36 |
|
double normsc(); |
37 |
|
/* sun calculation constants */ |
38 |
|
extern double s_latitude; |
44 |
|
int tsolar; /* 0=standard, 1=solar */ |
45 |
|
double altitude, azimuth; /* or solar angles */ |
46 |
|
/* default values */ |
47 |
< |
int cloudy = 0; /* 1=standard, 2=uniform */ |
47 |
> |
int skytype = S_CLEAR; /* sky type */ |
48 |
|
int dosun = 1; |
49 |
< |
double zenithbr = -1.0; |
49 |
> |
double zenithbr = 0.0; |
50 |
> |
int u_zenith = 0; /* -1=irradiance, 1=radiance */ |
51 |
|
double turbidity = 2.75; |
52 |
|
double gprefl = 0.2; |
53 |
|
/* computed values */ |
54 |
|
double sundir[3]; |
55 |
|
double groundbr; |
56 |
|
double F2; |
57 |
< |
double solarbr = -1.0; |
57 |
> |
double solarbr = 0.0; |
58 |
> |
int u_solar = 0; /* -1=irradiance, 1=radiance */ |
59 |
|
|
60 |
|
char *progname; |
61 |
|
char errmsg[128]; |
85 |
|
day = atoi(argv[2]); |
86 |
|
if (day < 1 || day > 31) |
87 |
|
userror("bad day"); |
88 |
< |
hour = atof(argv[3]); |
80 |
< |
if (hour < 0 || hour >= 24) |
81 |
< |
userror("bad hour"); |
82 |
< |
tsolar = argv[3][0] == '+'; |
88 |
> |
cvthour(argv[3]); |
89 |
|
} |
90 |
|
for (i = 4; i < argc; i++) |
91 |
|
if (argv[i][0] == '-' || argv[i][0] == '+') |
92 |
|
switch (argv[i][1]) { |
93 |
|
case 's': |
94 |
< |
cloudy = 0; |
94 |
> |
skytype = S_CLEAR; |
95 |
|
dosun = argv[i][0] == '+'; |
96 |
|
break; |
97 |
|
case 'r': |
98 |
+ |
case 'R': |
99 |
+ |
u_solar = argv[i][1]=='R' ? -1 : 1; |
100 |
|
solarbr = atof(argv[++i]); |
101 |
|
break; |
102 |
|
case 'c': |
103 |
< |
cloudy = argv[i][0] == '+' ? 2 : 1; |
96 |
< |
dosun = 0; |
103 |
> |
skytype = S_OVER; |
104 |
|
break; |
105 |
+ |
case 'u': |
106 |
+ |
skytype = S_UNIF; |
107 |
+ |
break; |
108 |
+ |
case 'i': |
109 |
+ |
skytype = S_INTER; |
110 |
+ |
dosun = argv[i][0] == '+'; |
111 |
+ |
break; |
112 |
|
case 't': |
113 |
|
turbidity = atof(argv[++i]); |
114 |
|
break; |
115 |
|
case 'b': |
116 |
+ |
case 'B': |
117 |
+ |
u_zenith = argv[i][1]=='B' ? -1 : 1; |
118 |
|
zenithbr = atof(argv[++i]); |
119 |
|
break; |
120 |
|
case 'g': |
145 |
|
|
146 |
|
computesky(); |
147 |
|
printsky(); |
148 |
+ |
|
149 |
+ |
exit(0); |
150 |
|
} |
151 |
|
|
152 |
|
|
153 |
|
computesky() /* compute sky parameters */ |
154 |
|
{ |
155 |
+ |
double normfactor; |
156 |
|
/* compute solar direction */ |
157 |
|
if (month) { /* from date and time */ |
158 |
|
int jd; |
166 |
|
st = hour + stadj(jd); |
167 |
|
altitude = salt(sd, st); |
168 |
|
azimuth = sazi(sd, st); |
169 |
+ |
printf("# Solar altitude and azimuth: %.1f %.1f\n", |
170 |
+ |
180./PI*altitude, 180./PI*azimuth); |
171 |
|
} |
172 |
< |
if (!cloudy && altitude > 87.*PI/180.) { |
172 |
> |
if (!overcast && altitude > 87.*PI/180.) { |
173 |
|
fprintf(stderr, |
174 |
|
"%s: warning - sun too close to zenith, reducing altitude to 87 degrees\n", |
175 |
|
progname); |
181 |
|
sundir[1] = -cos(azimuth)*cos(altitude); |
182 |
|
sundir[2] = sin(altitude); |
183 |
|
|
184 |
+ |
/* Compute normalization factor */ |
185 |
+ |
switch (skytype) { |
186 |
+ |
case S_UNIF: |
187 |
+ |
normfactor = 1.0; |
188 |
+ |
break; |
189 |
+ |
case S_OVER: |
190 |
+ |
normfactor = 0.777778; |
191 |
+ |
break; |
192 |
+ |
case S_CLEAR: |
193 |
+ |
F2 = 0.274*(0.91 + 10.0*exp(-3.0*(PI/2.0-altitude)) + |
194 |
+ |
0.45*sundir[2]*sundir[2]); |
195 |
+ |
normfactor = normsc()/F2/PI; |
196 |
+ |
break; |
197 |
+ |
case S_INTER: |
198 |
+ |
F2 = (2.739 + .9891*sin(.3119+2.6*altitude)) * |
199 |
+ |
exp(-(PI/2.0-altitude)*(.4441+1.48*altitude)); |
200 |
+ |
normfactor = normsc()/F2/PI; |
201 |
+ |
break; |
202 |
+ |
} |
203 |
|
/* Compute zenith brightness */ |
204 |
< |
if (zenithbr <= 0.0) |
205 |
< |
if (cloudy) { |
204 |
> |
if (u_zenith == -1) |
205 |
> |
zenithbr /= normfactor*PI; |
206 |
> |
else if (u_zenith == 0) { |
207 |
> |
if (overcast) |
208 |
|
zenithbr = 8.6*sundir[2] + .123; |
209 |
< |
zenithbr *= 1000.0/WHTEFFICACY; |
168 |
< |
} else { |
209 |
> |
else |
210 |
|
zenithbr = (1.376*turbidity-1.81)*tan(altitude)+0.38; |
211 |
< |
zenithbr *= 1000.0/SKYEFFICACY; |
212 |
< |
} |
213 |
< |
if (zenithbr < 0.0) |
214 |
< |
zenithbr = 0.0; |
174 |
< |
/* Compute horizontal radiance */ |
175 |
< |
if (cloudy) { |
176 |
< |
if (cloudy == 2) |
177 |
< |
groundbr = zenithbr; |
211 |
> |
if (skytype == S_INTER) |
212 |
> |
zenithbr = (zenithbr + 8.6*sundir[2] + .123)/2.0; |
213 |
> |
if (zenithbr < 0.0) |
214 |
> |
zenithbr = 0.0; |
215 |
|
else |
216 |
< |
groundbr = zenithbr*0.777778; |
180 |
< |
printf("# Ground ambient level: %f\n", groundbr); |
181 |
< |
} else { |
182 |
< |
F2 = 0.274*(0.91 + 10.0*exp(-3.0*(PI/2.0-altitude)) + |
183 |
< |
0.45*sundir[2]*sundir[2]); |
184 |
< |
groundbr = zenithbr*normsc(altitude)/F2/PI; |
185 |
< |
printf("# Ground ambient level: %f\n", groundbr); |
186 |
< |
if (sundir[2] > 0.0 && solarbr != 0.0) { |
187 |
< |
if (solarbr < 0.0) |
188 |
< |
solarbr = 1.5e9/SUNEFFICACY * |
189 |
< |
(1.147 - .147/(sundir[2]>.16?sundir[2]:.16)); |
190 |
< |
groundbr += solarbr*6e-5*sundir[2]/PI; |
191 |
< |
} else |
192 |
< |
dosun = 0; |
216 |
> |
zenithbr *= 1000.0/SKYEFFICACY; |
217 |
|
} |
218 |
+ |
/* Compute horizontal radiance */ |
219 |
+ |
groundbr = zenithbr*normfactor; |
220 |
+ |
printf("# Ground ambient level: %.1f\n", groundbr); |
221 |
+ |
if (!overcast && sundir[2] > 0.0 && (!u_solar || solarbr > 0.0)) { |
222 |
+ |
if (u_solar == -1) |
223 |
+ |
solarbr /= 6e-5*sundir[2]; |
224 |
+ |
else if (u_solar == 0) { |
225 |
+ |
solarbr = 1.5e9/SUNEFFICACY * |
226 |
+ |
(1.147 - .147/(sundir[2]>.16?sundir[2]:.16)); |
227 |
+ |
if (skytype == S_INTER) |
228 |
+ |
solarbr *= 0.15; /* fudge factor! */ |
229 |
+ |
} |
230 |
+ |
groundbr += 6e-5/PI*solarbr*sundir[2]; |
231 |
+ |
} else |
232 |
+ |
dosun = 0; |
233 |
|
groundbr *= gprefl; |
234 |
|
} |
235 |
|
|
246 |
|
} |
247 |
|
|
248 |
|
printf("\nvoid brightfunc skyfunc\n"); |
249 |
< |
printf("2 skybright skybright.cal\n"); |
249 |
> |
printf("2 skybr skybright.cal\n"); |
250 |
|
printf("0\n"); |
251 |
< |
if (cloudy) |
252 |
< |
printf("3 %d %.2e %.2e\n", cloudy, zenithbr, groundbr); |
251 |
> |
if (overcast) |
252 |
> |
printf("3 %d %.2e %.2e\n", skytype, zenithbr, groundbr); |
253 |
|
else |
254 |
< |
printf("7 -1 %.2e %.2e %.2e %f %f %f\n", zenithbr, groundbr, |
255 |
< |
F2, sundir[0], sundir[1], sundir[2]); |
254 |
> |
printf("7 %d %.2e %.2e %.2e %f %f %f\n", |
255 |
> |
skytype, zenithbr, groundbr, F2, |
256 |
> |
sundir[0], sundir[1], sundir[2]); |
257 |
|
} |
258 |
|
|
259 |
|
|
260 |
|
printdefaults() /* print default values */ |
261 |
|
{ |
262 |
< |
if (cloudy == 1) |
262 |
> |
switch (skytype) { |
263 |
> |
case S_OVER: |
264 |
|
printf("-c\t\t\t\t# Cloudy sky\n"); |
265 |
< |
else if (cloudy == 2) |
266 |
< |
printf("+c\t\t\t\t# Uniform cloudy sky\n"); |
267 |
< |
else if (dosun) |
268 |
< |
printf("+s\t\t\t\t# Sunny sky with sun\n"); |
269 |
< |
else |
270 |
< |
printf("-s\t\t\t\t# Sunny sky without sun\n"); |
265 |
> |
break; |
266 |
> |
case S_UNIF: |
267 |
> |
printf("-u\t\t\t\t# Uniform cloudy sky\n"); |
268 |
> |
break; |
269 |
> |
case S_INTER: |
270 |
> |
if (dosun) |
271 |
> |
printf("+i\t\t\t\t# Intermediate sky with sun\n"); |
272 |
> |
else |
273 |
> |
printf("-i\t\t\t\t# Intermediate sky without sun\n"); |
274 |
> |
break; |
275 |
> |
case S_CLEAR: |
276 |
> |
if (dosun) |
277 |
> |
printf("+s\t\t\t\t# Sunny sky with sun\n"); |
278 |
> |
else |
279 |
> |
printf("-s\t\t\t\t# Sunny sky without sun\n"); |
280 |
> |
break; |
281 |
> |
} |
282 |
|
printf("-g %f\t\t\t# Ground plane reflectance\n", gprefl); |
283 |
|
if (zenithbr > 0.0) |
284 |
|
printf("-b %f\t\t\t# Zenith radiance (watts/ster/m2\n", zenithbr); |
303 |
|
|
304 |
|
|
305 |
|
double |
306 |
< |
normsc(theta) /* compute normalization factor (E0*F2/L0) */ |
255 |
< |
double theta; |
306 |
> |
normsc() /* compute normalization factor (E0*F2/L0) */ |
307 |
|
{ |
308 |
< |
static double nf[5] = {2.766521, 0.547665, |
309 |
< |
-0.369832, 0.009237, 0.059229}; |
308 |
> |
static double nfc[2][5] = { |
309 |
> |
/* clear sky approx. */ |
310 |
> |
{2.766521, 0.547665, -0.369832, 0.009237, 0.059229}, |
311 |
> |
/* intermediate sky approx. */ |
312 |
> |
{3.5556, -2.7152, -1.3081, 1.0660, 0.60227}, |
313 |
> |
}; |
314 |
> |
register double *nf; |
315 |
|
double x, nsc; |
316 |
|
register int i; |
317 |
|
/* polynomial approximation */ |
318 |
< |
x = (theta - PI/4.0)/(PI/4.0); |
319 |
< |
nsc = nf[4]; |
320 |
< |
for (i = 3; i >= 0; i--) |
318 |
> |
nf = nfc[skytype==S_INTER]; |
319 |
> |
x = (altitude - PI/4.0)/(PI/4.0); |
320 |
> |
nsc = nf[i=4]; |
321 |
> |
while (i--) |
322 |
|
nsc = nsc*x + nf[i]; |
323 |
|
|
324 |
|
return(nsc); |
325 |
+ |
} |
326 |
+ |
|
327 |
+ |
|
328 |
+ |
cvthour(hs) /* convert hour string */ |
329 |
+ |
char *hs; |
330 |
+ |
{ |
331 |
+ |
register char *cp = hs; |
332 |
+ |
|
333 |
+ |
while (*cp && *cp++ != ':') |
334 |
+ |
; |
335 |
+ |
if (*cp) |
336 |
+ |
hour = atoi(hs) + atoi(cp)/60.0; |
337 |
+ |
else |
338 |
+ |
hour = atof(hs); |
339 |
+ |
tsolar = *hs == '+'; |
340 |
|
} |
341 |
|
|
342 |
|
|