--- ray/doc/man/man1/gendaymtx.1	2013/01/20 02:07:16	1.1
+++ ray/doc/man/man1/gendaymtx.1	2019/05/28 15:19:17	1.9
@@ -1,4 +1,4 @@
-.\" RCSid $Id: gendaymtx.1,v 1.1 2013/01/20 02:07:16 greg Exp $
+.\" RCSid $Id: gendaymtx.1,v 1.9 2019/05/28 15:19:17 greg Exp $
 .TH GENDAYMTX 1 01/19/13 RADIANCE
 .SH NAME
 gendaymtx - generate an annual Perez sky matrix from a weather tape
@@ -7,8 +7,12 @@ gendaymtx - generate an annual Perez sky matrix from a
 [
 .B "\-v"
 ][
+.B "\-h"
+][
 .B "\-d|\-s"
 ][
+.B "\-r deg"
+][
 .B "\-m N"
 ][
 .B "\-g r g b"
@@ -16,6 +20,8 @@ gendaymtx - generate an annual Perez sky matrix from a
 .B "\-c r g b"
 ][
 .B "-o{f|d}"
+][
+.B "-O{0|1}"
 ]
 [
 .B "tape.wea"
@@ -49,7 +55,7 @@ yield 8760x3 (26280) values per output line (row).
 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 gray value should equal 1 for proper energy balance.
 The default sky color is
 .I "\-c 0.960 1.004 1.118".
 Similarly, the
@@ -61,12 +67,37 @@ corresponding to a 20% gray.
 .PP
 The
 .I \-d
-option may be used to produce a sun-only matrix, with no sky contributions.
+option may be used to produce a sun-only matrix, with no sky contributions,
+and the ground patch also set to zero.
 Alternatively, the
 .I \-s
-option may be used to exclude any direct solar component from the output.
+option may be used to exclude any direct solar component from the output,
+with the rest of the sky and ground patch unaffected.
+If there is a sun in the description,
+.I gendaymtx
+will include its contribution in the four nearest sky patches,
+distributing energy according to centroid proximity.
 .PP
+By default,
+.I gendaymtx
+assumes the positive Y-axis points north such that the first sky patch
+is in the Y-axis direction on the horizon, the second patch is just
+west of that, and so on spiraling around to the final patch near the zenith.
 The
+.I \-r
+(or
+.I \-rz)
+option rotates the sky the specified number of degrees counter-clockwise
+about the zenith, i.e., west of north.
+This is in keeping with the effect of passing the output of
+.I gensky(1)
+or
+.I gendaylit(1)
+through
+.I xform(1)
+using a similar transform.
+.PP
+The
 .I \-of
 or
 .I \-od
@@ -74,6 +105,13 @@ option may be used to specify binary float or double o
 This is much faster to write and to read, and is therefore preferred on
 systems that support it.
 (MS Windows is not one of them.)\0
+The
+.I \-O1
+option specifies that output should be total solar radiance rather
+than visible radiance.
+The
+.I \-h
+option prevents the output of the usual header information.
 Finally, the
 .I \-v
 option will enable verbose reporting, which is mostly useful for
@@ -95,4 +133,5 @@ Ian Ashdown wrote most of the code,
 based on Jean-Jacques Delaunay's original gendaylit(1) implementation.
 Greg Ward wrote the final parameter parsing and weather tape conversion.
 .SH "SEE ALSO"
-dctimestep(1), genBSDF(1), gendaylit(1), genskyvec(1), rcontrib(1)
+dctimestep(1), genBSDF(1), gendaylit(1), gensky(1), genskyvec(1),
+rcollate(1), rcontrib(1), xform(1)