GXmap: User's guide
Copyright (C) 2008-2009 Anders Gavare
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How to use GXmap
When you start GXmap, you will see a 3D globe view of the world.
Screenshot (click to enlarge).
Note that tiles are not included in the GXmap program itself, but downloaded
on demand via the Internet. The first time you run GXmap, it will most likely
take a couple of seconds (or maybe even a minute), before a high-resolution
image can be rendered.
(Note as of release 1.5: Only OpenStreetMap tiles are downloaded in high
resolution; the 5400x2700 pixel NASA satellite image is static, and no higher
resolution image will be downloaded automatically.)
Zooming is accomplished by using the mouse scroll wheel.
Scrolling up zooms in, scrolling down zooms back out again.
- Rotating the globe
Place the mouse cursor on some part of the globe, hold down
the left mouse button, and "drag" the cursor to a new location.
While the mouse button is kept down, the map is rendered in low
resolution. When the button is released, the map will again be
rendered in high resolution.
The Ham (amateur radio) mode is entered by choosing Ham in the Mode menu.
In Ham mode, you will see multiple views of the world map. The
leftmost (main) view is the Azimuthal equidistant projection,
the top right view is a traditional 3D globe, and the bottom right view is
a plane 2D view with simple x,y = long,lat projection.
Screenshot (click to enlarge).
Below the 2D map, there are settings for QTH (home location), the other
station's location (if any), and a zoom slider.
Use the zoom slider to change the zoom level in the
map visualizations. (Note: The 2D view is not affected by
the zoom level. This is intentional, so that there is always
an overview map of the whole world.)
Zooming can also be accomplished by using the mouse scroll
- Changing QTH
1. Enter your Maidenhead locator coordinates, or longitude
and latitude, in the QTH entry fields.
2. Use the middle mouse button to click in any of the map
visualizations to set the QTH directly.
3. Hold down the left mouse button in the map visualizatons,
and "drag" to rotate the visualization. (Not
available in the 2D map.)
- Setting the location of the other station
1. Enter the other station's Maidenhead locator coordinates,
or longitude and latitude, in the Other station's entry fields.
2. Use the left mouse button directly in any of the map
visualizations to set the Other station's coordinates directly.
(Just click, don't drag around. Dragging around will change the
Once the location of the other station has been set,
the shortest path between the QTH and the other station will
be calculated, and shown using bright red in all visualizations.
- Unsetting/clearing the location of the other station
Clear the Other station's Maidenhead field. This removes
the shortest path calculation, including the red indicators.
When a shortest path between two locations has been calculated, the
status bar shows the direction (where 0 degrees is North, 90 degrees is East)
and distance in km.
Configuring map layers
There are two ways to reach the map layers configuration. The first is through
the Edit menu:
The second way is to right-click in a map visualization:
Currently, if there are multiple map visualizations, they all use the same
The available layers are:
Using GXmap with a GPS
Starting with release 1.3 of GXmap, GPS coordinates can be read from
The procedure for installing and running gpsd varies depending on operating
GXmap must be built with support for libgps. Usually, this is accomplished by
building GXmap after installing gpsd, or alternatively, it may have been
taken care of by a package maintainer (if you installed GXmap as a prebuilt
Examples using a USB-to-serial GPS device, such as a SiRF Navibe GM720:
- FreeBSD 7.2:
- Type pkg_add -r gpsd
- Plug in the device. It should show up as /dev/ttyU0.
- Type gpsd /dev/ttyU0
- Optionally, run cgps to see that gpsd and the
- Start GXmap.
- Ubuntu 9.04:
- Type apt-get install gpsd
- Type apt-get install libgps-dev (for building gxmap)
- Plug in the device. It should show up as /dev/ttyUSB0.
- Type gpsd /dev/ttyUSB0
- Optionally, run xgps to see that gpsd and the
- Start GXmap.
Whenever GXmap receives new GPS coordinates from gpsd, it updates the location
of a green cross to those coordinates. (Loosing the GPS fix will not remove the
green cross, however. It will just stay where it was last updated.)
Note (2009-05-22): At the time of writing this, there's a locale related bug
in libgps/gpsd 2.38, which causes longitude and latitude to be truncated to whole integer
values, for example when using a Swedish locale. If you experience this, as a temporary
workaround, try running GXmap using an English locale:
$ LANG=en gxmap