.TH xtide 1 "2009-09-10"  "XTide 2"
.SH NAME
xtide \- Harmonic tide clock and tide predictor (interactive client)
.SH SYNOPSIS
.B xtide
[\fB-aa y|n\fP]
[\fB-b ``YYYY-MM-DD HH:MM''\fP]
[\fB-bc color\fP]
[\fB-bg color\fP]
[\fB-cb y|n\fP]
[\fB-cc color\fP]
[\fB-ch pixels\fP]
[\fB-cw pixels\fP]
[\fB-dc color\fP]
[\fB-Dc color\fP]
[\fB-df ``format-string''\fP]
[\fB-display ``X display''\fP]
[\fB-ec color\fP]
[\fB-el y|n\fP]
[\fB-em pSsMm\fP]
[\fB-fc color\fP]
[\fB-fe y|n\fP]
[\fB-fg color\fP]
[\fB-fn font\fP]
[\fB-ga aspect\fP]
[\fB-geometry ``XOFFYOFF''\fP]
[\fB-gh pixels\fP]
[\fB-gl longitude\fP]
[\fB-gt y|n\fP]
[\fB-gw pixels\fP]
[\fB-hf ``format-string''\fP]
[\fB-in y|n\fP]
[\fB-l ``location name''\fP]
[\fB-lw pixels\fP]
[\fB-m a|g|k|m|p|r\fP]
[\fB-mc color\fP]
[\fB-Mc color\fP]
[\fB-ml [-]N.NN(ft|m|kt)\fP]
[\fB-nc color\fP]
[\fB-nf y|n\fP]
[\fB-tc color\fP]
[\fB-tf ``format-string''\fP]
[\fB-tl y|n\fP]
[\fB-u ft|m\fP]
[\fB-v\fP]
[\fB-z y|n\fP]
.SH DESCRIPTION
XTide is a package that provides tide and current predictions in a wide
variety of formats. Graphs, text listings, and calendars can be generated,
or a tide clock can be provided on your desktop.
.LP
XTide can work with X-windows, plain text terminals, or the web. This is
accomplished with three separate programs: the interactive interface
(\fBxtide\fP), the non-interactive or command line interface
(\fBtide\fP), and the web interface (\fBxttpd\fP).
.LP
.B xtide
is the interactive X-windows client for XTide 2.  Although in reality it
accepts many command line options, you should not need to use them;
everything can be done interactively.  Just run
.B xtide
and point and click your way to whatever you need.  If you get stuck,
click on a `?' button for on-line help.
.LP
For a complete
discussion of the command line options and a detailed explanation of the
interactive interface, please see the verbose documentation at
.BR http://www.flaterco.com/xtide/ .
.SH CONFIGURATION
Unless a configuration file
.B /etc/xtide.conf
is supplied, you must set the environment variable
.B HFILE_PATH
to point to the harmonics
files that should have been installed along with the
.B xtide
program.  Example:
.RS
export HFILE_PATH=/usr/local/share/xtide/harmonics.tcd
.RE
If a configuration file is used, the first line should consist of the
colon-separated list of harmonics files (e.g. the
.B HFILE_PATH
line above without the "export HFILE_PATH=" part).
The environment variable takes precedence over the configuration file.
Also, note that on Debian systems the tidal harmonics data file are stored in
.I /usr/share/xtide
instead of
.I /usr/local/share/xtide
as used above.
.LP
If the optional World Vector Shoreline files have been installed, the path to those
files can be supplied in the
.B WVS_DIR
environment variable or as the second line of the configuration file.
.LP
Set the environment variable
.B XTIDE_DEFAULT_LOCATION
to the name of your favorite place if you want to skip the location-choosing
step.
.SH OPTIONS
.TP
.B -aa y|n
Select whether or not to anti-alias tide graphs on true color displays
(default y).  Turning this off can greatly improve performance on CPU-bound
systems.
.TP
.B -b ``YYYY-MM-DD HH:MM''
Specify the begin (start) time for predictions using the ISO 8601
compliant format YYYY-MM-DD HH:MM, where hours
range from 00 to 23.  The timestamp is in the local time
zone for the location, or in UTC if the
.B -z
setting is engaged.  If clock mode is selected or if no
.B -b
is supplied, the current time will be used.
.TP
.B -bc color
Background color of buttons (default gray80).
.TP
.B -bg color
Background color for text windows and location chooser (default white).
.TP
.B -cb y|n
Select whether or not tide clocks should be created with buttons
(default n).
.TP
.B -cc color
Color of dots indicating current stations in the location chooser (default rgb:00/A0/00).
.TP
.B -ch pixels
Initial height for tide clocks (default 312 pixels).
.TP
.B -cw pixels
Initial width for tide clocks (default 84 pixels).
.TP
.B -dc color
Daytime background color in tide graphs (default SkyBlue).
.TP
.B -Dc color
Color of datum line in tide graphs (default white).
.TP
.B -df ``format-string''
.BR strftime (3)
style format string for printing dates (default %Y-%m-%d).
.TP
.B -display ``X display''
Specify the X display, e.g. "quake:0.0".  This overrides the DISPLAY
environment variable.
.TP
.B -ec color
Foreground in tide graphs during outgoing tide (default SeaGreen).
.TP
.B -el y|n
Select whether or not to draw datum and middle-level lines in tide graphs
(default n).
.TP
.B -em pSsMm
Events to suppress (p = phase of moon, S = sunrise, s = sunset, M = moonrise, m
= moonset), or x to suppress none.  E.g, to suppress all sun and moon events,
set eventmask to the value pSsMm.
.TP
.B -fc color
Foreground in tide graphs during incoming tide (default Blue).
.TP
.B -fe y|n
Select whether or not to prefer flat map to round globe location chooser
(default n).
.TP
.B -fg color
Color of text and other notations (default black).
.TP
.B -fn font
Font used for button labels and verbiage in text windows (default as
incoming from X11).  The font used in graphs and clocks cannot be changed.
.TP
.B -ga aspect
Initial aspect for tide graphs and clocks (default 1.0).  This controls not the
width or height of the window but rather the relative scaling of the X and Y
axes in the plot of the tide curve.
.TP
.B -geometry ``XOFFYOFF''
Specify a position for the window corresponding to the first use of
.BR -l .
(Width and height are controlled by different settings.)
.TP
.B -gh pixels
Initial height for tide graphs (default 312 pixels).
.TP
.B -gl longitude
Initial center longitude for location chooser.
Valid values are -180 -150 -120 -90 -60 -30 0 30 60 90 120 150 and 360.
360 (the default) will pick the longitude with the most tide stations.
.TP
.B -gt y|n
Select whether or not to label tenths of units in tide graphs
(default n).
.TP
.B -gw pixels
Initial width for tide graphs (default 960 pixels).
.TP
.B -hf ``format-string''
.BR strftime (3)
style format string for printing hour labels on time axis (default %l).
.TP
.B -in y|n
Select whether or not to use inferred values for some constituents (default n).
For expert use only.
.TP
.B -l ``location name''
Specify a location for tide predictions. When given to the interactive
client, this causes it to start a tide clock for the specified location
instead of launching a location chooser on startup. This is useful for
starting a tide clock automatically when you log on. Multiple uses of
.B -l
will result in multiple tide clocks.
.TP
.B -lw pixels
Width for lines in tide graphs with
.B -nf
(default 2.5 pixels).
.TP
.B -m a|g|k|m|p|r
Specify mode to be about, graph, clock, medium rare, plain, or raw.
The default is clock.
.TP
.B -mc color
Color of mark line in graphs (default red).
.TP
.B -Mc color
Color of middle-level line in tide graphs (default yellow).
.TP
.B -ml [-]N.NN(ft|m|kt)
Specify an initial mark level to be used in prediction windows launched from
the command line.  The predictions will include the times when the tide level
crosses the mark.  The mark level also can be specified or changed using the
Options menu.  Not supported in clock mode.  Does not affect windows that are
launched from the location chooser.  Example usage: -ml -0.25ft
.TP
.B -nc color
Nighttime background color in tide graphs (default DeepSkyBlue).
.TP
.B -nf y|n
Select whether or not to draw tide graphs as line graphs
(default n).
.TP
.B -tc color
Color of dots indicating tide stations in the location chooser (default red).
.TP
.B -tf ``format-string''
.BR strftime (3)
style format string for printing times (default %l:%M %p %Z).
.TP
.B -tl y|n
Select whether or not to draw depth lines on top of the tide graph
(default n).
.TP
.B -u ft|m
Preferred units of length (default no preference).
.TP
.B -v
Print version string and exit.
.TP
.B -z y|n
Select whether or not to coerce all time zones to UTC (default n).
.SH "SEE ALSO"
.BR tide (1),
.BR xttpd (8),
.BR http://www.flaterco.com/xtide/ .
.sp