Defining Marker Files

Marker files provide user-defined context on a map.  They signify points on a map, and they can be represent static items like cities or dynamic items like storms, earthquakes, and active volcanoes.  Marker files contain little more than entries to note the latitude, the longitude, and a defined name.

The benefit of using marker files is in the context they provide the map.  The marker files, along with the night time map, help make the final rendering a more personal image. Without the markers, you’re left with half the story.  The story of Earth and our relationship with her is better told with the marker files.

Earth Marker

The marker file for the location of many of Earth’s cities is included with Xplanet.  Copy the file to your Xplanet home location and open up your favorite Mac text editor.

cp /usr/local/share/xplanet/markers/earth ~/.xplanet/markers/

Some tips when editing marker files:

  • Place a # at the front of the line to comment out a line
  • To add the date and time next to the name of a city add the following to the end of the city name in the marker file: “New York” would change to “New York %r %Z (%a)”
    • Remember the quotes
  • You can manually add any location to the map by adding the latitude, longitude, name of the city within double quotes, and optionally the time zone to the marker file

Save the marker file.  You can test the marker file with the following command.

### Only need to do this once to create a dummy config file
cd ~/.xplanet
echo "[earth]" >> test-cfg
echo "marker_file=earth" >> test-cfg

xplanet -searchdir ~/.xplanet -projection rectangular -config test-cfg -num_times=1

### When you're happy with the edits to the marker file
rm test-cfg

You can use any preferred projection, but I would stay away from the default, gnomonic, icosagnomonic, and orthographic projections for testing purposes because they will limit your field of view.

Storm, Earthquake, and Volcano Markers

TotalMarker.  There are other scripts that are available to help bring the Xplanet rendering alive, but TotalMarker does it in a way that doesn’t interfere or take away from the final image.  The marker files from TotalMarker do complement the overall map.  TotalMarker offers standalone binaries to create marker files locally yourself and hosts marker files remotely that you can download.

*** 9/12/2017 Update – There seem to be some issues with TotalMarker and the storm marker.  Appears the storm information site that TotalMarker uses is no longer updating with the storm information.

We’re going to use TotalMarker to grab four markers although they make a couple others available.  Three marker files will overlay onto our final image showing: earthquakes within the past week, active storms, and active volcanoes.  The last marker is actually a label file.  I grab this file for debugging purposes because I generate my own label marker.

TotalMarker supports 2 ½ operating systems: Windows, Linux, and Power PC Macs.  Since the current versions of OS X no longer support Power PC Macs, and Apple no longer supports Rosetta on Intel Macs, the TotalMarker Mac binary is useless.  So we’re going to grab the marker files directly from the TotalMarker website.

There is a way you can run TotalMarker locally on your Intel Mac that I’ve documented in Final Thoughts, but the scripts I use on the next page get the marker files remotely.  You can certainly modify the scripts to instead run TotalMarker locally.

At this point, we have or have access to everything we need.  We will now need to create some scripts to automatically put the right files in the right place at the right time.


One Response to Defining Marker Files

  1. Stephan Irle says:

    A concoction of scripts and cron commands represents my screen saver. Living in Japan, the earthquake markers and also typhoon indicators matter most.

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