.\"
.\" (C) Copyright 2018 Alec Leamas <leamas.alec@gmail.com>,
.\"
.TH Opencpn 1 "July 2018"

.SH NAME
opencpn \- Chartplotter and GPS Navigation Software
.SH SYNOPSIS
.B opencpn
.RI [ options ]
.SH DESCRIPTION
OpenCPN is a chartplotter and navigation GUI program supporting navigation
under way as well as planning. It supports a wide range of chart formats
using a plugin system. Other plugins provides support for e. g. radar, AIS
and weather maps. Program is localized in 20+ languages and ported to
several OS including MacOS, Windows and Linux.

.SH OPTIONS
.TP
.B \-h, \-\-help
Show help info.
.TP
.B \-p
Run in portable mode.
.TP
.B  \-l, \-\-loglevel=<level>
Set amount of logged information. Level is any of \fItrace\fR,
\fIdebug\fR, \fIinfo\fR, \fImessage\fR, \fIwarning\fR or \fIerror\fR,
defaulting to \fIinfo\fR if not set in environment; see ENVIRONMENT.

.TP
.B  \-fullscreen
Switch to full screen mode on start.
.TP
.B  \-no_opengl
Disable OpenGL video acceleration. This setting will be remembered.
.TP
.B  \-rebuild_gl_raster_cache
Rebuild OpenGL raster cache on start.
.TP
.B  \-parse_all_enc
Convert all S-57 charts to OpenCPN's internal format on start.
.TP
.B  \-unit_test_1:<num>
Display a slideshow of <num> charts and then exit. Zero or negative <num>
specifies no limit.

.SH PLUGIN LOADING

Plugin loading depends on that the opencpn main program can locate the
plugin object file and that the plugin can locate it's own data.
.P
On Linux, the main program searches for plugin .so-files in a library
named \fIopencpn/plugins\fR.
By default, this path is searched in ~/.local/lib:/usr/local/lib:/usr/lib.
The default search path can be overridden by the OPENCPN_PLUGIN_DIRS
environment variable.
.P
On other platforms, all plugin object files lives in a single directory
defined at installation.
.P
A plugin's data directory is a path ending with
\fIopencpn/plugins/<plugin_name>\fR.
On Linux, this is by default searched in
~/local/share:/usr/local/share:/usr/share.
This search path is overridden by XDG_DATA_DIRS as defined by the freedesktop
spec.
Only plugins adapted for this (i. e., using GetPluginDataDir()) handles this
properly.
.P
On other platforms, the plugin data directories always lives in a common
parent defined at installation time.

.SH LIBRARY LOADING AND LD_LIBRARY_PATH

If \fILD_LIBRARY_PATH\fR exists in the environment \fBopencpn\fR uses it
without modifications.
.P
Otherwise \fILD_LIBRARY_PATH\fR is set to the same path as from which plugins are
loaded, see above. This ensures that helper binaries can load possible libraries
installed in the same directories as the plugin.

.SH ENVIRONMENT
.TP
.B OPENCPN_PLUGIN_DIRS
Plugin load path, see PLUGIN LOADING
.TP
.B OPENCPN_LOGLEVEL
Default loglevel if not defined on command line using -l/--loglevel. See
the --loglevel option for allowed values.
.TP
.B OPENCPN_FATAL_ERROR
If defined, displays the message and exits on startup.

.SH FILES
.TP
.B ~/.opencpn/opencpn.log
System log file, a useful tool to solve problems.


.SH NOTES

The support for OPENCPN_PLUGIN_DIRS and XDG_DATA_DIRS was introduced in
version 5.0.0. Prior to this, all plugins was loaded from a single directory
and all plugin data directories had a common parent.

.SH SEE ALSO
.br
http://www.opencpn.org
.br
http://www.freedesktop.org