man/man1/genskyvec.1

.\" RCSid $Id: genskyvec.1,v 1.3 2012/06/14 22:42:21 greg Exp $
.TH GENSKYVEC 1 12/09/09 RADIANCE
.SH NAME
genskyvec - compute patch radiance averages for a specific sky
.SH SYNOPSIS
.B genskyvec
[
.B "\-m N"
][
.B "\-c r g b"
][
.B "\-d"
]
.SH DESCRIPTION
.I Genskyvec
samples the
.I Radinace
sky description given on the standard input to generate a list of
average patch radiances.
If there is a sun in the description,
.I genskyvec
will include its contribution in the three nearest sky patches,
distributing energy according to centroid proximity.
.PP
By default,
.I genskyvec
divides the sky into 2305 patches, plus one patch for the ground.
This corresponds to Reinhart's extension of the Tregenza sky,
where the original 145 patches are subdivided into 16 subpatches,
except at the zenith.
A different subdivision may be specified via the
.I \-m
option.
The value given will be used to subdivide each dimension, so the
default of 4 yields almost 16 times as many patches
as the original Tregenza sky, which can be specified with
.I "\-m 1."
A higher resolution sky is generally better for daylight
coefficient analysis where solar position is important.
.PP
The
.I \-c
option may be used to specify a color for the sky.
The gray value should equal 1 for proper energy balance
The default sky color is
.I "\-c 0.960 1.004 1.118".
.PP
The
.I \-d
option may be used to produce a sun-only vector, with no sky contributions.
If a time of day is selected or sky type that has no sun, then a zero vector
is produced.
.SH EXAMPLE
To generate 578 patches corresponding to a 2x2 subdivision of the
Tregenza sky on a sunny equinox noon:
.IP "" .2i
gensky 9 21 12 | genskyvec -m 2 > sky09_21_12.dat
.SH AUTHOR
Greg Ward
.SH "SEE ALSO"
dctimestep(1), genBSDF(1), gensky(1), gentregvec(1), rcontrib(1), rtrace(1)
Revision:	1.4
Committed:	Thu Jun 28 20:48:03 2012 UTC (12 years, 10 months ago) by greg
Branch:	MAIN
Changes since 1.3:	+9 -1 lines
Log Message:	Added -d option for sun-only vector
#	Content
1	.\" RCSid $Id: genskyvec.1,v 1.3 2012/06/14 22:42:21 greg Exp $
2	.TH GENSKYVEC 1 12/09/09 RADIANCE
3	.SH NAME
4	genskyvec - compute patch radiance averages for a specific sky
5	.SH SYNOPSIS
6	.B genskyvec
7	[
8	.B "\-m N"
9	][
10	.B "\-c r g b"
11	][
12	.B "\-d"
13	]
14	.SH DESCRIPTION
15	.I Genskyvec
16	samples the
17	.I Radinace
18	sky description given on the standard input to generate a list of
19	average patch radiances.
20	If there is a sun in the description,
21	.I genskyvec
22	will include its contribution in the three nearest sky patches,
23	distributing energy according to centroid proximity.
24	.PP
25	By default,
26	.I genskyvec
27	divides the sky into 2305 patches, plus one patch for the ground.
28	This corresponds to Reinhart's extension of the Tregenza sky,
29	where the original 145 patches are subdivided into 16 subpatches,
30	except at the zenith.
31	A different subdivision may be specified via the
32	.I \-m
33	option.
34	The value given will be used to subdivide each dimension, so the
35	default of 4 yields almost 16 times as many patches
36	as the original Tregenza sky, which can be specified with
37	.I "\-m 1."
38	A higher resolution sky is generally better for daylight
39	coefficient analysis where solar position is important.
40	.PP
41	The
42	.I \-c
43	option may be used to specify a color for the sky.
44	The gray value should equal 1 for proper energy balance
45	The default sky color is
46	.I "\-c 0.960 1.004 1.118".
47	.PP
48	The
49	.I \-d
50	option may be used to produce a sun-only vector, with no sky contributions.
51	If a time of day is selected or sky type that has no sun, then a zero vector
52	is produced.
53	.SH EXAMPLE
54	To generate 578 patches corresponding to a 2x2 subdivision of the
55	Tregenza sky on a sunny equinox noon:
56	.IP "" .2i
57	gensky 9 21 12 \| genskyvec -m 2 > sky09_21_12.dat
58	.SH AUTHOR
59	Greg Ward
60	.SH "SEE ALSO"
61	dctimestep(1), genBSDF(1), gensky(1), gentregvec(1), rcontrib(1), rtrace(1)