--- /dev/null
+TerraSync
+=========
+
+Usage:
+
+ terrasync -p <port> [ -s <rsync_source> ] -d <rsync_dest>
+
+Example:
+
+ $ fgfs --atlas=socket,out,1,localhost,5500,udp --fg-scenery=/data1/Scenery-0.7.9
+ $ nice terrasync -p 5500 -d /data1/Scenery-0.7.9
+
+Requirements:
+
+ - rsync util installed in your path.
+ - mkdir util installed in your path.
+
+TerraSync is a utility that is intended to run as a light weight
+background process. It's purpose is to monitor the position of a
+FlightGear flight and pre-fetch scenery tiles from a remote server
+based on the current FlightGear position.
+
+This allows you to do a base install of FlightGear with no add on
+scenery. Now just go and fly anywhere. Scenery is fetched "just in
+time" and accumulated on your HD so it is already there next time you
+fly. You can fly anywhere and essentially just the scenery you need
+is auto-installed as you fly.
+
+Terrasync runs as a separate process and expects the --atlas=port
+format to be sent from fgfs. The fgfs output tells the terrasync util
+where FlightGear is currently flying. Terrasync will then issue the
+appropriate commands to rsync the surrounding areas to your local
+scenery directory. The user need to choose a port for
+FlightGear->TerraSync communication and then specify the server
+location and destation scenery tree.
+
+As you fly, terrasync will periodically refresh and pull any new
+scenery tiles that you need for your position from the server.
+
+This also works if the scenery on the scenery server is updated.
+Rsync will pull any missing files, or any updated files.
+
+There is a chicken/egg problem when you first start up in a brand new
+area. FlightGear is expecting the scenery to be there *now* but it
+may not have been fetched yet. I suppose without making a more
+complex protocol, the user will need to be aware of this. The user
+could restart flightgear after the initial rsync completes, and then
+after that everything should be good, assuming the flight track is
+"continuous" and the user has the necessary bandwidth to keep up with
+flight speeds.
+
+Final notes:
+
+I have set up an initial scenery server at
+baron.flightgear.org::Scenery-0.7.9. This is the 0.7.9 vintage
+scenery with airports rebuilt to include lighting. Alex Perry also
+has a partial rsync server, but I don't know it's current status.
+William Riley has rebuilt the entire world, but the tiles are zipped
+in 10x10 degree chunks on on a relatively low bandwidth connection.
+There are aspects of the 0.7.9 scenery I like including the quality of
+the terrain, but William scenery has roads and streams which is also
+nice.
--- /dev/null
+// terrasync.cxx -- "JIT" scenery fetcher
+//
+// Written by Curtis Olson, started November 2002.
+//
+// Copyright (C) 2002 Curtis L. Olson - curt@flightgear.org
+//
+// 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+//
+// $Id$
+
+
+#include <stdlib.h> // atoi() atof() abs() system()
+
+#include <simgear/compiler.h>
+
+#include STL_IOSTREAM
+#include STL_STRING
+
+#include <plib/netSocket.h>
+#include <plib/ul.h>
+
+#include <simgear/bucket/newbucket.hxx>
+
+SG_USING_STD(string);
+SG_USING_STD(cout);
+SG_USING_STD(endl);
+
+
+static string server = "baron.flightgear.org";
+static string source_module = "Scenery-0.7.9";
+static string source_base = server + (string)"::" + source_module;
+static string dest_base = "/dest/scenery/dir";
+
+
+// display usage
+static void usage( const string& prog ) {
+ cout << "Usage: " << prog
+ << " -p <port> [ -s <rsync_source> ] -d <rsync_dest>" << endl;
+}
+
+
+// parse message
+static void parse_message( const string &msg, int *lat, int *lon ) {
+ double dlat, dlon;
+ string text = msg;
+
+ // find GGA string and advance to start of lat
+ string::size_type pos = text.find( "$GPGGA" );
+ string tmp = text.substr( pos + 7 );
+ pos = text.find( "," );
+ tmp = tmp.substr( pos + 1 );
+ // cout << "-> " << tmp << endl;
+
+ // find lat then advance to start of hemisphere
+ pos = tmp.find( "," );
+ string lats = tmp.substr( 0, pos );
+ dlat = atof( lats.c_str() ) / 100.0;
+ tmp = tmp.substr( pos + 1 );
+
+ // find N/S hemisphere and advance to start of lon
+ if ( tmp.substr( 0, 1 ) == "S" ) {
+ dlat = -dlat;
+ }
+ pos = tmp.find( "," );
+ tmp = tmp.substr( pos + 1 );
+
+ // find lon
+ pos = tmp.find( "," );
+ string lons = tmp.substr( 0, pos );
+ dlon = atof( lons.c_str() ) / 100.0;
+ tmp = tmp.substr( pos + 1 );
+
+ // find E/W hemisphere and advance to start of lon
+ if ( tmp.substr( 0, 1 ) == "W" ) {
+ dlon = -dlon;
+ }
+
+ if ( dlat < 0 ) {
+ *lat = (int)dlat - 1;
+ } else {
+ *lat = (int)dlat;
+ }
+
+ if ( dlon < 0 ) {
+ *lon = (int)dlon - 1;
+ } else {
+ *lon = (int)dlon;
+ }
+}
+
+
+// sync area
+static void sync_area( int lat, int lon ) {
+ char NS, EW;
+ int baselat, baselon;
+
+ if ( lat < 0 ) {
+ int base = (int)(lat / 10);
+ if ( lat == base * 10 ) {
+ baselat = base * 10;
+ } else {
+ baselat = (base - 1) * 10;
+ }
+ NS = 's';
+ } else {
+ baselat = (int)(lat / 10) * 10;
+ NS = 'n';
+ }
+ if ( lon < 0 ) {
+ int base = (int)(lon / 10);
+ if ( lon == base * 10 ) {
+ baselon = base * 10;
+ } else {
+ baselon = (base - 1) * 10;
+ }
+ EW = 'w';
+ } else {
+ baselon = (int)(lon / 10) * 10;
+ EW = 'e';
+ }
+
+ char command[512];
+
+ // make container directory
+ char container_dir[512];
+ snprintf( container_dir, 512, "%s/%c%03d%c%02d",
+ dest_base.c_str(), EW, abs(baselon), NS, abs(baselat) );
+ snprintf( command, 512, "mkdir -p %s", container_dir );
+ cout << command << endl;
+ system( command );
+
+ char dir[512];
+ snprintf( dir, 512, "%c%03d%c%02d/%c%03d%c%02d",
+ EW, abs(baselon), NS, abs(baselat),
+ EW, abs(lon), NS, abs(lat) );
+
+ snprintf( command, 512,
+ "rsync --verbose --archive --delete --perms --owner --group %s/%s/ %s/%s",
+ source_base.c_str(), dir, dest_base.c_str(), dir );
+ cout << command << endl;
+ system( command );
+}
+
+
+// sync areas
+static void sync_areas( int lat, int lon, int lat_dir, int lon_dir ) {
+ // do current 1x1 degree area first
+ sync_area( lat, lon );
+
+ if ( lat_dir == 0 && lon_dir == 0 ) {
+ // now do surrounding 8 1x1 degree areas.
+ for ( int i = lat - 1; i <= lat + 1; ++i ) {
+ for ( int j = lon - 1; j <= lon + 1; ++j ) {
+ if ( i != lat || j != lon ) {
+ sync_area( i, j );
+ }
+ }
+ }
+ } else {
+ if ( lat_dir != 0 ) {
+ sync_area( lat + lat_dir, lon );
+ sync_area( lat + lat_dir, lon - 1 );
+ sync_area( lat + lat_dir, lon + 1 );
+ }
+ if ( lon_dir != 0 ) {
+ sync_area( lat, lon + lon_dir );
+ sync_area( lat - 1, lon + lon_dir );
+ sync_area( lat + 1, lon + lon_dir );
+ }
+ }
+}
+
+
+int main( int argc, char **argv ) {
+ int port = 5501;
+ char host[256] = ""; // accept messages from anyone
+
+ // parse arguments
+ int i = 1;
+ while ( i < argc ) {
+ if ( (string)argv[i] == "-p" ) {
+ ++i;
+ port = atoi( argv[i] );
+ } else if ( (string)argv[i] == "-s" ) {
+ ++i;
+ source_base = argv[i];
+ } else if ( (string)argv[i] == "-d" ) {
+ ++i;
+ dest_base = argv[i];
+ } else {
+ usage( argv[0] );
+ exit(-1);
+ }
+ ++i;
+ }
+
+ // Must call this before any other net stuff
+ netInit( &argc,argv );
+
+ netSocket s;
+
+ if ( ! s.open( false ) ) { // open a UDP socket
+ printf("error opening socket\n");
+ return -1;
+ }
+
+ s.setBlocking( false );
+
+ if ( s.bind( host, port ) == -1 ) {
+ printf("error binding to port %d\n", port);
+ return -1;
+ }
+
+ char msg[256];
+ int maxlen = 256;
+ int len;
+ int lat, lon;
+ int last_lat = -9999;
+ int last_lon = -9999;
+ bool recv_msg = false;
+
+ while ( true ) {
+ recv_msg = false;
+ while ( (len = s.recv(msg, maxlen, 0)) >= 0 ) {
+ msg[len] = '\0';
+ recv_msg = true;
+
+ parse_message( msg, &lat, &lon );
+ cout << "pos = " << lat << "," << lon << endl;
+ }
+
+ if ( recv_msg ) {
+ if ( lat != last_lat || lon != last_lon ) {
+ int lat_dir, lon_dir, dist;
+ if ( last_lat == -9999 || last_lon == -9999 ) {
+ lat_dir = lon_dir = 0;
+ } else {
+ dist = lat - last_lat;
+ if ( dist != 0 ) {
+ lat_dir = dist / abs(dist);
+ } else {
+ lat_dir = 0;
+ }
+ dist = lon - last_lon;
+ if ( dist != 0 ) {
+ lon_dir = dist / abs(dist);
+ } else {
+ lon_dir = 0;
+ }
+ }
+ cout << "lat = " << lat << " lon = " << lon << endl;
+ cout << "lat_dir = " << lat_dir << " " << " lon_dir = " << lon_dir << endl;
+ sync_areas( lat, lon, lat_dir, lon_dir );
+ }
+
+ last_lat = lat;
+ last_lon = lon;
+ }
+
+ ulSleep( 1 );
+ }
+
+ return 0;
+}
projects / flightgear.git / commitdiff