2017-06-04 13:32:38 +00:00
|
|
|
.\" Copyright (C) 2017 Alessandro Menti
|
|
|
|
|
.\"
|
|
|
|
|
.\" This program is free software; you can redistribute it and/or
|
|
|
|
|
.\" modify it under the terms of the GNU General Public License
|
|
|
|
|
.\" as published by the Free Software Foundation; either version 2
|
|
|
|
|
.\" of the License, or (at your option) any later version.
|
|
|
|
|
.\"
|
|
|
|
|
.\" This program is distributed in the hope that it will be useful,
|
|
|
|
|
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
|
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
|
|
.\" GNU General Public License for more details.
|
|
|
|
|
.\"
|
|
|
|
|
.\" You should have received a copy of the GNU General Public License
|
|
|
|
|
.\" along with this program; if not, write to the Free Software
|
|
|
|
|
.\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
|
|
|
.\" Or try here: http://www.fsf.org/copyleft/gpl.html
|
|
|
|
|
.\"
|
2020-11-15 21:47:18 +00:00
|
|
|
.TH FGELEV 1 2020-11-15 FlightGear "FlightGear man pages"
|
2017-06-04 13:32:38 +00:00
|
|
|
.SH NAME
|
|
|
|
|
fgelev \- Compute FlightGear scenery elevation for a given list of points
|
|
|
|
|
.SH SYNOPSIS
|
|
|
|
|
\fBfgelev\fR [\fB\-\-expire\fR \fInum\fR] [\fB\-\-print\-solidness\fR]
|
|
|
|
|
[\fB\-\-fg\-root\fR \fIrootdir\fR] [\fB\-\-fg\-scenery\fR \fIscenerydir\fR]
|
2020-11-15 21:47:18 +00:00
|
|
|
[--tile-file osgbfilename] [--use-vpb]
|
2017-06-04 13:32:38 +00:00
|
|
|
.SH DESCRIPTION
|
|
|
|
|
.B fgelev
|
|
|
|
|
is a standalone utility that, given a list of points on standard input, prints
|
|
|
|
|
the corresponding elevation for each of them on standard output. It can also
|
|
|
|
|
(optionally) print whether the material covering that point is solid or not.
|
|
|
|
|
|
|
|
|
|
The list of points must be in the following form:
|
|
|
|
|
|
|
|
|
|
\fIid lon lat\fR
|
|
|
|
|
|
|
|
|
|
where \fIid\fR is an arbitrary identifier for the point, \fIlon\fR is the
|
|
|
|
|
longitude of the point and \fIlat\fR is the latitude of the point. Positive
|
|
|
|
|
longitudes (latitudes) correspond to points located in the Eastern (Northern)
|
|
|
|
|
hemisphere; negative ones correspond to points located in the Western
|
|
|
|
|
(Southern) hemisphere.
|
|
|
|
|
|
|
|
|
|
The list of elevations returned by
|
|
|
|
|
.B fgelev
|
|
|
|
|
is in the following form:
|
|
|
|
|
|
|
|
|
|
\fIid: elev solid\fR
|
|
|
|
|
|
|
|
|
|
where \fIid\fR is the identifier of the point passed as input, \fIelev\fR is
|
|
|
|
|
the elevation of the point in meters (or \fB-1000\fR if the elevation of the
|
|
|
|
|
given point was not found) and \fIsolid\fR is:
|
|
|
|
|
.IP \(bu 3
|
|
|
|
|
the string
|
|
|
|
|
.B solid
|
|
|
|
|
if the parameter
|
|
|
|
|
.B \-\-print\-solidness
|
|
|
|
|
was passed to
|
|
|
|
|
.B fgelev
|
|
|
|
|
and the material covering the point is solid;
|
|
|
|
|
.IP \(bu 3
|
|
|
|
|
the string
|
|
|
|
|
.B \-
|
|
|
|
|
if the parameter
|
|
|
|
|
.B \-\-print\-solidness
|
|
|
|
|
was passed to
|
|
|
|
|
.B fgelev
|
|
|
|
|
and the material covering the point is not solid;
|
|
|
|
|
.IP \(bu 3
|
|
|
|
|
absent if the parameter
|
|
|
|
|
.B \-\-print\-solidness
|
|
|
|
|
was not passed to \fBfgelev\fR.
|
|
|
|
|
.SH OPTIONS
|
|
|
|
|
.TP
|
|
|
|
|
\fB\-\-expire\fR \fInum\fR
|
|
|
|
|
To speed up elevation data retrieval,
|
|
|
|
|
.B fgelev
|
|
|
|
|
uses an internal cache. This option lets the user specify the number of
|
|
|
|
|
requests after which, if a point was not queried in them, it should be marked
|
|
|
|
|
as expired. By default,
|
|
|
|
|
.B fgelev
|
|
|
|
|
expires points not queried in the last \fB10\fR requests.
|
|
|
|
|
.TP
|
|
|
|
|
\fB\-\-print\-solidness\fR
|
|
|
|
|
Require
|
|
|
|
|
.B fgelev
|
|
|
|
|
to print the solidness of the material covering the queried point. See the
|
|
|
|
|
.B DESCRIPTION
|
|
|
|
|
section for more details.
|
|
|
|
|
.TP
|
|
|
|
|
\fB\-\-fg\-root\fR \fIrootdir\fR
|
|
|
|
|
Set the FlightGear data root directory (\fB$FG_ROOT\fR) to \fIrootdir\fR. If
|
|
|
|
|
this option is not set,
|
|
|
|
|
.B fgelev
|
|
|
|
|
uses the path specified in the
|
|
|
|
|
.B FG_ROOT
|
|
|
|
|
environment variable or, absent that, the FlightGear data directory chosen at
|
|
|
|
|
the time the program was compiled.
|
|
|
|
|
.TP
|
|
|
|
|
\fB\-\-fg\-scenery\fR \fIscenerydir\fR
|
|
|
|
|
Set the FlightGear scenery directory (\fB$FG_SCENERY\fR) to \fIscenerydir\fR.
|
|
|
|
|
If this option is not set,
|
|
|
|
|
.B fgelev
|
|
|
|
|
uses the path specified in the
|
|
|
|
|
.B FG_SCENERY
|
|
|
|
|
environment variable or, absent that, the
|
|
|
|
|
.B Scenery
|
|
|
|
|
subdirectory inside \fB$FG_ROOT\fR.
|
2020-11-15 21:47:18 +00:00
|
|
|
.TP
|
|
|
|
|
\fB\-\-tile\-file\fR \fIosgbfilename\fR
|
|
|
|
|
Use a specific tile file when searching for elevation details, instead
|
|
|
|
|
of scanning through the whole world.
|
|
|
|
|
.TP
|
|
|
|
|
\fB\-\-use\-vpb\fR
|
|
|
|
|
If specified, enables WS3.0 scenery behaviour, searching under the vpb/
|
|
|
|
|
subdirectory.
|
2017-06-04 13:32:38 +00:00
|
|
|
.SH "EXIT STATUS"
|
|
|
|
|
.B fgelev
|
|
|
|
|
exits with
|
|
|
|
|
.B EXIT_SUCCESS
|
|
|
|
|
on success, with
|
|
|
|
|
.B EXIT_FAILURE
|
|
|
|
|
if it is unable to read data from standard input or to load the scenery.
|
|
|
|
|
.SH ENVIRONMENT
|
|
|
|
|
.IP "\fBFG_ROOT\fR" 4
|
|
|
|
|
If
|
|
|
|
|
.B FG_ROOT
|
|
|
|
|
is set and
|
|
|
|
|
.B \-\-fg\-root
|
|
|
|
|
is not set, it specifies the root data directory to use.
|
|
|
|
|
.IP "\fBFG_SCENERY\fR" 4
|
|
|
|
|
If
|
|
|
|
|
.B FG_SCENERY
|
|
|
|
|
is set and
|
|
|
|
|
.B \-\-fg\-scenery
|
|
|
|
|
is not set, it specifies the scenery directory to use.
|
|
|
|
|
.SH "SEE ALSO"
|
|
|
|
|
.BR fgfs (1)
|
