Live-feed support for Google Earth.

4 files changed, 130 insertions, 6 deletions

diff --git a/NEWS b/NEWS
index 79f7041b..6a993778 100644
--- a/NEWS
+++ b/NEWS
@@ -12,7 +12,8 @@
   an scons build recipe. Direct support for activation of gpsd from
   Mac OS/X systemd. gpsdecode can now filter reports by RTCM2, RTCM3,
   or AIS message type. NMEA HEHDT is implemented. Remote gpsd instances
-  ca now be used as data sources via a gpsd:// URL.
+  can now be used as data sources via a gpsd:// URL.  There is a client
+  for live-feeding GPSD data to Google Earth. 
 
 * Mon Mar 21 2011 Eric S. Raymond <esr@snark.thyrsus.com> - 2.96
   Bumped maximum channel count to 32 to accommodate GPS+GLONASS devices.
diff --git a/SConstruct b/SConstruct
index 0eb441f8..ed01ed62 100644
--- a/SConstruct
+++ b/SConstruct
@@ -738,7 +738,7 @@ if cxx and env["libgpsmm"]:
     testprogs.append(test_gpsmm)
 
 # Python programs
-python_progs = ["gpscat", "gpsfake", "gpsprof", "xgps", "xgpsspeed"]
+python_progs = ["gpscat", "gpsfake", "gpsprof", "xgps", "xgpsspeed", "gegps"]
 python_modules = Glob('gps/*.py') 
 
 # Build Python binding
@@ -884,6 +884,7 @@ python_manpages = {
     "gpscat.1" : "gpscat.xml",
     "xgpsspeed.1" : "gps.xml",
     "xgps.1" : "gps.xml",
+    "gegps.1" : "gps.xml",
     }
 
 manpage_targets = []
diff --git a/gegps b/gegps
new file mode 100644
index 00000000..725568ef
--- /dev/null
+++ b/gegps
@@ -0,0 +1,101 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+# usage: gegps [-i] [-d kmldir]
+#
+# Feed location data from a running GPSD to a Google Earth instance.
+# The -d argument is the location of the Google Earth installation
+# directory.  If not specified, it defaults to the current directory.
+#
+# If you have the free (non-subscription) version, start by running with
+# the -i option to drop a clue in the Google Earth installation directory,
+# as 'Open_in_Google_Earth_RT_GPS.kml', then open that file in Places
+# (File > Open...),
+#
+# The basic recipe is here:
+# http://tjworld.net/wiki/Linux/Ubuntu/GoogleEarthPlusRealTimeGPS
+#
+# This code originally by Jaroslaw Zachwieja and a guy referring
+# to himself/herself as TJ(http://tjworld.net)
+# Modified by Chen Wei <weichen302@aol.com> for use with gpsd
+# Cleaned up and adapted for the GPSD project by Eric S. Raymond.
+
+import time, os, gps, getopt
+import sys
+
+KML_OPEN_IN_GE = '''\
+<?xml version="1.0" encoding="UTF-8"?>
+<kml xmlns="http://earth.google.com/kml/2.2">
+<NetworkLink>
+	<name>Realtime GPS</name>
+	<open>1</open>
+	<Link>
+		<href>Realtime_GPS.kml</href>
+		<refreshMode>onInterval</refreshMode>
+	</Link>
+</NetworkLink>
+</kml>
+'''
+
+def kmlize(tpv):
+    '''http://code.google.com/apis/kml/documentation/kmlreference.html
+       for official kml document'''
+    latitude =  tpv['lat']
+    longitude = tpv['lon']
+    speed_in =  tpv['speed'] # meter/second
+    speed = speed_in * gps.MPS_TO_KPH # Km/h
+    heading =   int(round(tpv['track'], 0))
+    altitude =  tpv['alt']
+
+    if speed < 1:
+        heading = 0
+
+    return """<?xml version="1.0" encoding="UTF-8"?>
+<kml xmlns="http://earth.google.com/kml/2.0">
+<Placemark>
+    <name>%s km/h,heading %s</name>
+    <description>Realtime GPS feeding</description>
+    <LookAt>
+        <longitude>%s</longitude>
+        <latitude>%s</latitude>
+    </LookAt>
+    <Point>
+        <coordinates>%s,%s,%s</coordinates>
+    </Point>
+</Placemark>
+</kml>""" % (speed,heading,longitude,latitude,longitude,latitude,altitude)
+
+
+if __name__ == "__main__":
+    session = gps.gps()
+    # must include gps.WATCH_NEWSTYLE on my system(debian squeeze), otherwise
+    # there is no TPV report
+    session.stream(gps.WATCH_ENABLE|gps.WATCH_NEWSTYLE)
+
+    kmldir = "."
+    initialize = False
+    (options, arguments) = getopt.getopt(sys.argv[1:], "d:i")
+    for (opt, arg) in options:
+        if opt == '-d':
+            kmldir = arg
+        elif opt == '-i':
+            initialize = True
+
+    if initialize:
+        f = open(os.path.join(kmldir, 'Open_in_Google_Earth_RT_GPS.kml'), 'w')
+        f.write(KML_OPEN_IN_GE)
+        f.close()
+    else:
+        try:
+            while True:
+                report = session.next()
+                if report['class'] == 'TPV':
+                    f = open(os.path.join(kmldir, 'Realtime_GPS.kml'), 'w')
+                    f.write(kmlize(report))
+                    f.close()
+        except StopIteration:
+            pass
+        except KeyboardInterrupt:
+            print 'gegpsd stopped '
+
+# end
diff --git a/gps.xml b/gps.xml
index d3efb855..75de1c5c 100644
--- a/gps.xml
+++ b/gps.xml
@@ -89,9 +89,6 @@ BSD terms apply: see the file COPYING in the distribution root for details.
       </group>
 </cmdsynopsis>
 <cmdsynopsis>
-  <command>gpxlogger</command>
-</cmdsynopsis>
-<cmdsynopsis>
   <command>gpxlogger</command>  
       <arg choice='opt'>-D <replaceable>debug-level</replaceable></arg>
       <arg choice='opt'>-d </arg>
@@ -110,6 +107,11 @@ BSD terms apply: see the file COPYING in the distribution root for details.
 	  </group>
       </group>
 </cmdsynopsis>
+<cmdsynopsis>
+  <command>gegps</command>
+      <arg choice='opt'>-d <replaceable>directory</replaceable></arg>
+      <arg choice='opt'>-i </arg>
+</cmdsynopsis>
 </refsynopsisdiv>
 
 <refsect1 id='description'><title>DESCRIPTION</title>
@@ -299,6 +301,24 @@ defaulted to, you may give a server-port-device specification as
 arguments.</para>
 
 </refsect2>
+<refsect2><title>gegps</title>
+
+<para>This program collects fixes from <application>gpsd</application>
+and feeds them to a running instance of Google Earth for live location 
+tracking.</para>
+
+<para>The <option>-d</option> argument is the location of the Google
+Earth installation directory.  If not specified, it defaults to the
+current directory.</para>
+
+<para>If you have the free (non-subscription) version, start by
+running with the <option>-i</option> option to drop a clue in the
+Google Earth installation directory, as
+'Open_in_Google_Earth_RT_GPS.kml', then open that file in Places (File
+> Open...). Run <application>gpsd</application> in the normal way
+after that.</para>
+
+</refsect2>
 </refsect1>
 <refsect1 id='see_also'><title>SEE ALSO</title>
 <para>
@@ -320,7 +340,8 @@ arguments.</para>
 Remco Treffcorn, Derrick Brashear, Russ Nelson &amp; Eric S. Raymond,
 Jeff Francis (cgps). Amaury Jacquot <email>sxpert@sxpert.org</email>
 &amp; Petter Reinholdtsen <email>pere@hungry.com</email> (gpxlogger).
-Chris Kuethe <email>chris.kuethe@gmail.com</email> (gpxlogger).
+Chris Kuethe <email>chris.kuethe@gmail.com</email> (gpxlogger), Chen
+Wei <email>weichen302@aol.com</email> (gegps).
 </para>
 
 <para>This manual page by Eric S. Raymond <email>esr@thyrsus.com</email>.