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src/FDM/NullFDM.cxx

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+// NullFDM.hxx -- a do-nothing flight model, used as a placeholder if the
+//                action is externally driven.
+// Written by Curtis Olson, started November 1999.
+//
+// Copyright (C) 1999 - 2001  Curtis L. Olson  - http://www.flightgear.org/~curt
+//
+// 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.
+//
+// $Id$
+
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include "NullFDM.hxx"
+
+
+FGNullFDM::FGNullFDM( double dt ) {
+//     set_delta_t( dt );
+}
+
+
+FGNullFDM::~FGNullFDM() {
+}
+
+
+// Initialize the NullFDM flight model, dt is the time increment
+// for each subsequent iteration through the EOM
+void FGNullFDM::init() {
+    //do init common to all the FDM's		
+    common_init();
+    // cout << "FGNullFDM::init()" << endl;
+    set_inited( true );
+}
+
+
+// Run an iteration of the EOM.  This is a NOP here because the flight
+// model values are getting filled in elsewhere (most likely from some
+// external source.)
+void FGNullFDM::update( double dt ) {
+    // cout << "FGNullFDM::update()" << endl;
+    // That is just to trigger ground level computations
+    _updateGeodeticPosition(get_Latitude(), get_Longitude(), get_Altitude());
+}
+
+
+// Register the subsystem.
+#if 0
+SGSubsystemMgr::Registrant<FGNullFDM> registrantFGNullFDM;
+#endif