37 |
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9 8 7 6 5 0 |
38 |
|
|
39 |
|
CET EET AST GST IST JST NZST |
40 |
< |
-1 -2 -3 -4 -5.5 -9 -12 |
40 |
> |
\-1 \-2 \-3 \-4 \-5.5 \-9 \-12 |
41 |
|
|
42 |
|
Daylight savings time: |
43 |
|
YDT PDT MDT CDT EDT BST |
44 |
< |
8 7 6 5 4 -1 |
44 |
> |
8 7 6 5 4 \-1 |
45 |
|
|
46 |
|
CEST EEST ADT GDT IDT JDT NZDT |
47 |
< |
-2 -3 -4 -5 -6.5 -10 -13 |
47 |
> |
\-2 \-3 \-4 \-5 \-6.5 \-10 \-13 |
48 |
|
.fi |
49 |
|
.PP |
50 |
|
If the time is preceded by a plus sign ('+'), then it is interpreted |
97 |
|
description to use with the |
98 |
|
.I \-av |
99 |
|
option of the RADIANCE rendering programs. |
100 |
< |
(See rview(1) and rpict(1).) |
100 |
> |
(See rvu(1) and rpict(1).) |
101 |
|
This value is the cosine-weighted radiance of the sky in |
102 |
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watts/steradian/meter2. |
103 |
|
.PP |
104 |
|
.I Gensky |
105 |
|
supports the following options. |
106 |
|
.TP 10n |
107 |
+ |
.BR \-y \ year |
108 |
+ |
If the year is specified, a more accurate solar position algorithm |
109 |
+ |
[Michalsky 1988] will be used in place of the formula in the IES |
110 |
+ |
Lighting Handbook. |
111 |
+ |
.TP |
112 |
|
.BR \-s |
113 |
|
Sunny sky without sun. |
114 |
|
The sky distribution will correspond to a standard CIE clear day. |
216 |
|
(Use negative angle for east.) |
217 |
|
This is used in the calculation of solar time. |
218 |
|
Be sure to give the correct longitude also! |
219 |
< |
If solar time is given directly, then this option has no effect. |
219 |
> |
If a time zone or solar time is given directly, then this option has no effect. |
220 |
|
.SH EXAMPLE |
221 |
|
To produce a sunny sky for July 4th at 2:30pm Eastern daylight time at a |
222 |
|
site latitude of 42 degrees, 89 degrees west longitude: |
223 |
|
.IP "" .2i |
224 |
< |
gensky 7 4 14:30EDT +s -a 42 -o 89 |
224 |
> |
gensky 7 4 14:30EDT +s \-a 42 \-o 89 |
225 |
|
.PP |
226 |
|
To produce a sunny sky distribution for a specific sun position but |
227 |
|
without the sun description: |
228 |
|
.IP "" .2i |
229 |
< |
gensky -ang 23 -40 -s |
229 |
> |
gensky \-ang 23 \-40 \-s |
230 |
|
.SH FILES |
231 |
|
/usr/local/lib/ray/skybright.cal |
232 |
|
.SH AUTHOR |
233 |
|
Greg Ward |
234 |
|
.SH "SEE ALSO" |
235 |
< |
rpict(1), rview(1), xform(1) |
235 |
> |
rpict(1), rvu(1), xform(1) |