From: curt <curt>
Date: Thu, 9 Sep 1999 00:16:28 +0000 (+0000)
Subject: Fiddling around with views, fdm data passing and management to try to be
X-Git-Url: https://git.mxchange.org/?a=commitdiff_plain;h=1b45c9ee546523709bc0d31277864eccf1a80b73;p=flightgear.git

Fiddling around with views, fdm data passing and management to try to be
more sensible so we can do a more reasonable external view.
---

diff --git a/src/Aircraft/aircraft.hxx b/src/Aircraft/aircraft.hxx
index 1ef175ad1..a05a4cb3a 100644
--- a/src/Aircraft/aircraft.hxx
+++ b/src/Aircraft/aircraft.hxx
@@ -38,7 +38,7 @@
 
 // Define a structure containing all the parameters for an aircraft
 typedef struct{
-    FGInterface   *fdm_state;
+    FGInterface *fdm_state;
     FGControls *controls;
 } fgAIRCRAFT ;
 
diff --git a/src/FDM/flight.hxx b/src/FDM/flight.hxx
index 5afc060c4..4e81f042d 100644
--- a/src/FDM/flight.hxx
+++ b/src/FDM/flight.hxx
@@ -81,10 +81,17 @@
  */
 
 
+#include <Include/compiler.h>
+
 #include <math.h>
 
+#include <list>
+
 #include <Time/timestamp.hxx>
 
+FG_USING_STD(list);
+
+
 #ifndef __cplusplus                                                          
 # error This library requires C++
 #endif                                   
@@ -839,6 +846,11 @@ public:
 };
 
 
+typedef list < FGInterface > fdm_state_list;
+typedef fdm_state_list::iterator fdm_state_list_iterator;
+typedef fdm_state_list::const_iterator const_fdm_state_list_iterator;
+
+
 extern FGInterface cur_fdm_state;
 
 
diff --git a/src/Main/fg_init.cxx b/src/Main/fg_init.cxx
index f8b40b6c9..894f5e61a 100644
--- a/src/Main/fg_init.cxx
+++ b/src/Main/fg_init.cxx
@@ -218,7 +218,6 @@ bool fgInitGeneral( void ) {
 bool fgInitSubsystems( void ) {
     FGTime::cur_time_params = new FGTime();
 
-    FGInterface *f; // assigned later
     fgLIGHT *l = &cur_light_params;
     FGTime *t = FGTime::cur_time_params;
     FGView *v = &current_view;
@@ -229,7 +228,6 @@ bool fgInitSubsystems( void ) {
     // allocates structures so must happen before any of the flight
     // model or control parameters are set
     fgAircraftInit();   // In the future this might not be the case.
-    f = current_aircraft.fdm_state;
 
     // set the initial position
     fgInitPosition();
@@ -265,13 +263,13 @@ bool fgInitSubsystems( void ) {
     // now handled inside of the fgTileMgrUpdate()
 
     /*
-    geod_pos = Point3D( f->get_Longitude(), f->get_Latitude(), 0.0);
+    geod_pos = Point3D( cur_fdm_state.get_Longitude(), cur_fdm_state.get_Latitude(), 0.0);
     tmp_abs_view_pos = fgGeodToCart(geod_pos);
 
     FG_LOG( FG_GENERAL, FG_DEBUG,
     	    "Initial abs_view_pos = " << tmp_abs_view_pos );
     scenery.cur_elev =
-	fgTileMgrCurElev( f->get_Longitude(), f->get_Latitude(),
+	fgTileMgrCurElev( cur_fdm_state.get_Longitude(), cur_fdm_state.get_Latitude(),
 			  tmp_abs_view_pos );
     FG_LOG( FG_GENERAL, FG_DEBUG,
 	    "Altitude after update " << scenery.cur_elev );
@@ -281,19 +279,19 @@ bool fgInitSubsystems( void ) {
 			     scenery.cur_elev );
 
     // Reset our altitude if we are below ground
-    FG_LOG( FG_GENERAL, FG_DEBUG, "Current altitude = " << f->get_Altitude() );
+    FG_LOG( FG_GENERAL, FG_DEBUG, "Current altitude = " << cur_fdm_state.get_Altitude() );
     FG_LOG( FG_GENERAL, FG_DEBUG, "Current runway altitude = " <<
-	    f->get_Runway_altitude() );
+	    cur_fdm_state.get_Runway_altitude() );
 
-    if ( f->get_Altitude() < f->get_Runway_altitude() + 3.758099) {
-	f->set_Altitude( f->get_Runway_altitude() + 3.758099 );
+    if ( cur_fdm_state.get_Altitude() < cur_fdm_state.get_Runway_altitude() + 3.758099) {
+	cur_fdm_state.set_Altitude( cur_fdm_state.get_Runway_altitude() + 3.758099 );
     }
 
     FG_LOG( FG_GENERAL, FG_INFO,
 	    "Updated position (after elevation adj): ("
-	    << (f->get_Latitude() * RAD_TO_DEG) << ", "
-	    << (f->get_Longitude() * RAD_TO_DEG) << ", "
-	    << (f->get_Altitude() * FEET_TO_METER) << ")" );
+	    << (cur_fdm_state.get_Latitude() * RAD_TO_DEG) << ", "
+	    << (cur_fdm_state.get_Longitude() * RAD_TO_DEG) << ", "
+	    << (cur_fdm_state.get_Altitude() * FEET_TO_METER) << ")" );
 
     // We need to calculate a few more values here that would normally
     // be calculated by the FDM so that the v->UpdateViewMath()
@@ -302,43 +300,43 @@ bool fgInitSubsystems( void ) {
     double sea_level_radius_meters;
     double lat_geoc;
     // Set the FG variables first
-    fgGeodToGeoc( f->get_Latitude(), f->get_Altitude(),
+    fgGeodToGeoc( cur_fdm_state.get_Latitude(), cur_fdm_state.get_Altitude(),
 		  &sea_level_radius_meters, &lat_geoc);
-    f->set_Geocentric_Position( lat_geoc, f->get_Longitude(),
-				f->get_Altitude() +
+    cur_fdm_state.set_Geocentric_Position( lat_geoc, cur_fdm_state.get_Longitude(),
+				cur_fdm_state.get_Altitude() +
 				(sea_level_radius_meters * METER_TO_FEET) );
-    f->set_Sea_level_radius( sea_level_radius_meters * METER_TO_FEET );
+    cur_fdm_state.set_Sea_level_radius( sea_level_radius_meters * METER_TO_FEET );
 
-    f->set_sin_cos_longitude(f->get_Longitude());
-    f->set_sin_cos_latitude(f->get_Latitude());
+    cur_fdm_state.set_sin_cos_longitude(cur_fdm_state.get_Longitude());
+    cur_fdm_state.set_sin_cos_latitude(cur_fdm_state.get_Latitude());
 	
-    f->set_sin_lat_geocentric(sin(lat_geoc));
-    f->set_cos_lat_geocentric(cos(lat_geoc));
+    cur_fdm_state.set_sin_lat_geocentric(sin(lat_geoc));
+    cur_fdm_state.set_cos_lat_geocentric(cos(lat_geoc));
 
     // The following section sets up the flight model EOM parameters
     // and should really be read in from one or more files.
 
     // Initial Velocity
-    f->set_Velocities_Local( current_options.get_uBody(),
+    cur_fdm_state.set_Velocities_Local( current_options.get_uBody(),
                              current_options.get_vBody(),
                              current_options.get_wBody());
 
     // Initial Orientation
-    f->set_Euler_Angles( current_options.get_roll() * DEG_TO_RAD,
+    cur_fdm_state.set_Euler_Angles( current_options.get_roll() * DEG_TO_RAD,
 			 current_options.get_pitch() * DEG_TO_RAD,
 			 current_options.get_heading() * DEG_TO_RAD );
 
     // Initial Angular Body rates
-    f->set_Omega_Body( 7.206685E-05, 0.0, 9.492658E-05 );
+    cur_fdm_state.set_Omega_Body( 7.206685E-05, 0.0, 9.492658E-05 );
 
-    f->set_Earth_position_angle( 0.0 );
+    cur_fdm_state.set_Earth_position_angle( 0.0 );
 
     // Mass properties and geometry values
-    f->set_Inertias( 8.547270E+01,
+    cur_fdm_state.set_Inertias( 8.547270E+01,
 		     1.048000E+03, 3.000000E+03, 3.530000E+03, 0.000000E+00 );
 
     // CG position w.r.t. ref. point
-    f->set_CG_Position( 0.0, 0.0, 0.0 );
+    cur_fdm_state.set_CG_Position( 0.0, 0.0, 0.0 );
 
     // Initialize the event manager
     global_events.Init();
@@ -350,14 +348,14 @@ bool fgInitSubsystems( void ) {
 			    fgEVENT::FG_EVENT_READY, 60000 );
 
     // Initialize the time dependent variables
-    t->init(f);
-    t->update(f);
+    t->init(cur_fdm_state);
+    t->update(cur_fdm_state);
 
     // Initialize view parameters
     FG_LOG( FG_GENERAL, FG_DEBUG, "Before v->init()");
     v->Init();
     FG_LOG( FG_GENERAL, FG_DEBUG, "After v->init()");
-    v->UpdateViewMath(f);
+    v->UpdateViewMath(cur_fdm_state);
     FG_LOG( FG_GENERAL, FG_DEBUG, "  abs_view_pos = " << v->get_abs_view_pos());
     // v->UpdateWorldToEye(f);
 
@@ -448,17 +446,17 @@ bool fgInitSubsystems( void ) {
 
     // I'm just sticking this here for now, it should probably move
     // eventually
-    scenery.cur_elev = f->get_Runway_altitude() * FEET_TO_METER;
+    scenery.cur_elev = cur_fdm_state.get_Runway_altitude() * FEET_TO_METER;
 
-    if ( f->get_Altitude() < f->get_Runway_altitude() + 3.758099) {
-	f->set_Altitude( f->get_Runway_altitude() + 3.758099 );
+    if ( cur_fdm_state.get_Altitude() < cur_fdm_state.get_Runway_altitude() + 3.758099) {
+	cur_fdm_state.set_Altitude( cur_fdm_state.get_Runway_altitude() + 3.758099 );
     }
 
     FG_LOG( FG_GENERAL, FG_INFO,
 	    "Updated position (after elevation adj): ("
-	    << (f->get_Latitude() * RAD_TO_DEG) << ", "
-	    << (f->get_Longitude() * RAD_TO_DEG) << ", "
-	    << (f->get_Altitude() * FEET_TO_METER) << ")" );
+	    << (cur_fdm_state.get_Latitude() * RAD_TO_DEG) << ", "
+	    << (cur_fdm_state.get_Longitude() * RAD_TO_DEG) << ", "
+	    << (cur_fdm_state.get_Altitude() * FEET_TO_METER) << ")" );
     // end of thing that I just stuck in that I should probably move
 
     // Joystick support
@@ -484,7 +482,6 @@ bool fgInitSubsystems( void ) {
 
 void fgReInitSubsystems( void )
 {
-    FGInterface *f = current_aircraft.fdm_state;
     FGView *v = &current_view;
     FGTime *t = FGTime::cur_time_params;
     
@@ -505,69 +502,69 @@ void fgReInitSubsystems( void )
 			     scenery.cur_elev );
 
     // Reset our altitude if we are below ground
-    FG_LOG( FG_GENERAL, FG_DEBUG, "Current altitude = " << f->get_Altitude() );
+    FG_LOG( FG_GENERAL, FG_DEBUG, "Current altitude = " << cur_fdm_state.get_Altitude() );
     FG_LOG( FG_GENERAL, FG_DEBUG, "Current runway altitude = " << 
-	    f->get_Runway_altitude() );
+	    cur_fdm_state.get_Runway_altitude() );
 
-    if ( f->get_Altitude() < f->get_Runway_altitude() + 3.758099) {
-	f->set_Altitude( f->get_Runway_altitude() + 3.758099 );
+    if ( cur_fdm_state.get_Altitude() < cur_fdm_state.get_Runway_altitude() + 3.758099) {
+	cur_fdm_state.set_Altitude( cur_fdm_state.get_Runway_altitude() + 3.758099 );
     }
     double sea_level_radius_meters;
     double lat_geoc;
     // Set the FG variables first
-    fgGeodToGeoc( f->get_Latitude(), f->get_Altitude(), 
+    fgGeodToGeoc( cur_fdm_state.get_Latitude(), cur_fdm_state.get_Altitude(), 
 		  &sea_level_radius_meters, &lat_geoc);
-    f->set_Geocentric_Position( lat_geoc, f->get_Longitude(), 
-				f->get_Altitude() + 
+    cur_fdm_state.set_Geocentric_Position( lat_geoc, cur_fdm_state.get_Longitude(), 
+				cur_fdm_state.get_Altitude() + 
 				(sea_level_radius_meters * METER_TO_FEET) );
-    f->set_Sea_level_radius( sea_level_radius_meters * METER_TO_FEET );
+    cur_fdm_state.set_Sea_level_radius( sea_level_radius_meters * METER_TO_FEET );
 	
-    f->set_sin_cos_longitude(f->get_Longitude());
-    f->set_sin_cos_latitude(f->get_Latitude());
+    cur_fdm_state.set_sin_cos_longitude(cur_fdm_state.get_Longitude());
+    cur_fdm_state.set_sin_cos_latitude(cur_fdm_state.get_Latitude());
 	
-    f->set_sin_lat_geocentric(sin(lat_geoc));
-    f->set_cos_lat_geocentric(cos(lat_geoc));
+    cur_fdm_state.set_sin_lat_geocentric(sin(lat_geoc));
+    cur_fdm_state.set_cos_lat_geocentric(cos(lat_geoc));
 
     // The following section sets up the flight model EOM parameters
     // and should really be read in from one or more files.
 
     // Initial Velocity
-    f->set_Velocities_Local( current_options.get_uBody(),
+    cur_fdm_state.set_Velocities_Local( current_options.get_uBody(),
                              current_options.get_vBody(),
                              current_options.get_wBody());
 
     // Initial Orientation
-    f->set_Euler_Angles( current_options.get_roll() * DEG_TO_RAD,
+    cur_fdm_state.set_Euler_Angles( current_options.get_roll() * DEG_TO_RAD,
 			 current_options.get_pitch() * DEG_TO_RAD,
 			 current_options.get_heading() * DEG_TO_RAD );
 
     // Initial Angular Body rates
-    f->set_Omega_Body( 7.206685E-05, 0.0, 9.492658E-05 );
+    cur_fdm_state.set_Omega_Body( 7.206685E-05, 0.0, 9.492658E-05 );
 
-    f->set_Earth_position_angle( 0.0 );
+    cur_fdm_state.set_Earth_position_angle( 0.0 );
 
     // Mass properties and geometry values
-    f->set_Inertias( 8.547270E+01, 
+    cur_fdm_state.set_Inertias( 8.547270E+01, 
 		     1.048000E+03, 3.000000E+03, 3.530000E+03, 0.000000E+00 );
 
     // CG position w.r.t. ref. point
-    f->set_CG_Position( 0.0, 0.0, 0.0 );
+    cur_fdm_state.set_CG_Position( 0.0, 0.0, 0.0 );
 
     // Initialize view parameters
     FG_LOG( FG_GENERAL, FG_DEBUG, "Before v->init()");
     v->Init();
     FG_LOG( FG_GENERAL, FG_DEBUG, "After v->init()");
-    v->UpdateViewMath(f);
+    v->UpdateViewMath(cur_fdm_state);
     FG_LOG( FG_GENERAL, FG_DEBUG, "  abs_view_pos = " << v->get_abs_view_pos());
     // v->UpdateWorldToEye(f);
 
     fgFDMInit( current_options.get_flight_model(), cur_fdm_state, 
 	       1.0 / current_options.get_model_hz() );
 
-    scenery.cur_elev = f->get_Runway_altitude() * FEET_TO_METER;
+    scenery.cur_elev = cur_fdm_state.get_Runway_altitude() * FEET_TO_METER;
 
-    if ( f->get_Altitude() < f->get_Runway_altitude() + 3.758099) {
-	f->set_Altitude( f->get_Runway_altitude() + 3.758099 );
+    if ( cur_fdm_state.get_Altitude() < cur_fdm_state.get_Runway_altitude() + 3.758099) {
+	cur_fdm_state.set_Altitude( cur_fdm_state.get_Runway_altitude() + 3.758099 );
     }
 
     controls.reset_all();
diff --git a/src/Main/keyboard.cxx b/src/Main/keyboard.cxx
index 508b5f25d..de273655b 100644
--- a/src/Main/keyboard.cxx
+++ b/src/Main/keyboard.cxx
@@ -301,7 +301,7 @@ void GLUTkey(unsigned char k, int x, int y) {
 	    local_update_sky_and_lighting_params();
 	    return;
 	case 118: // v key
-	    v->cycle_view_mode();
+	    current_options.cycle_view_mode();
 	    return;
 	case 120: // x key
 	    fov = current_options.get_fov();
diff --git a/src/Main/main.cxx b/src/Main/main.cxx
index 0317b0d77..d3eb1822b 100644
--- a/src/Main/main.cxx
+++ b/src/Main/main.cxx
@@ -224,7 +224,7 @@ static void fgInitVisuals( void ) {
 static void fgRenderFrame( void ) {
     fgLIGHT *l = &cur_light_params;
     FGTime *t = FGTime::cur_time_params;
-    FGView *v = &current_view;
+    // FGView *v = &current_view;
 
     double angle;
     // GLfloat black[4] = { 0.0, 0.0, 0.0, 1.0 };
@@ -251,7 +251,7 @@ static void fgRenderFrame( void ) {
 	// end of hack
 
 	// update view volume parameters
-	v->UpdateViewParams();
+	current_view.UpdateViewParams(cur_fdm_state);
 
 	// set the sun position
 	xglLightfv( GL_LIGHT0, GL_POSITION, l->sun_vec );
@@ -285,7 +285,7 @@ static void fgRenderFrame( void ) {
 	xglMatrixMode(GL_MODELVIEW);
 	xglLoadIdentity();
 	sgMat4 vm_tmp, view_mat;
-	sgTransposeNegateMat4 ( vm_tmp, v->sgVIEW ) ;
+	sgTransposeNegateMat4 ( vm_tmp, current_view.sgVIEW ) ;
 	sgCopyMat4( view_mat, copy_of_ssgOpenGLAxisSwapMatrix ) ;
 	sgPreMultMat4( view_mat, vm_tmp ) ;
 	xglLoadMatrixf( (float *)view_mat );
@@ -303,7 +303,7 @@ static void fgRenderFrame( void ) {
 	// setup transformation for drawing astronomical objects
 	xglPushMatrix();
 	// Translate to view position
-	Point3D view_pos = v->get_view_pos();
+	Point3D view_pos = current_view.get_view_pos();
 	xglTranslatef( view_pos.x(), view_pos.y(), view_pos.z() );
 	// Rotate based on gst (sidereal time)
 	// note: constant should be 15.041085, Curt thought it was 15
@@ -376,22 +376,25 @@ static void fgRenderFrame( void ) {
 	    ssgSetNearFar( 0.5f, 100000.0f );
 	}
 
-	sgMat4 sgVIEW;
+	// sgMat4 sgVIEW;
+	// while ( current_view.follow.size() > 25 ) {
+	//    current_view.follow.pop_front();
+	// }
 
-	while ( current_view.follow.size() > 400 ) {
-	    current_view.follow.pop_front();
-	}
-
-	if ( current_view.view_mode == FGView::FG_VIEW_FIRST_PERSON ) {
+	if ( current_options.get_view_mode() == 
+	     fgOPTIONS::FG_VIEW_FIRST_PERSON )
+        {
 	    // select current view matrix
-	    sgCopyMat4( sgVIEW, current_view.sgVIEW );
+	    // sgCopyMat4( sgVIEW, current_view.sgVIEW );
 
 	    // disable TuX
 	    penguin_sel->select(0);
-	} else if ( current_view.view_mode == FGView::FG_VIEW_FOLLOW ) {
+	} else if ( current_options.get_view_mode() == 
+		    fgOPTIONS::FG_VIEW_FOLLOW )
+        {
 	    // select view matrix from front of view matrix queue
-	    FGMat4Wrapper tmp = current_view.follow.front();
-	    sgCopyMat4( sgVIEW, tmp.m );
+	    // FGMat4Wrapper tmp = current_view.follow.front();
+	    // sgCopyMat4( sgVIEW, tmp.m );
 
 	    // enable TuX and set up his position and orientation
 	    penguin_sel->select(1);
@@ -418,7 +421,7 @@ static void fgRenderFrame( void ) {
 	    penguin_pos->setTransform( &tuxpos );
 	}
 
-	ssgSetCamera( sgVIEW );
+	ssgSetCamera( current_view.sgVIEW );
 
 	// position tile nodes and update range selectors
 	global_tile_mgr.prep_ssg_nodes();
@@ -455,10 +458,11 @@ static void fgRenderFrame( void ) {
 
 // Update internal time dependent calculations (i.e. flight model)
 void fgUpdateTimeDepCalcs(int multi_loop, int remainder) {
-    FGInterface *f = current_aircraft.fdm_state;
+    static fdm_state_list fdm_list;
+    FGInterface fdm_state;
     fgLIGHT *l = &cur_light_params;
     FGTime *t = FGTime::cur_time_params;
-    FGView *v = &current_view;
+    // FGView *v = &current_view;
     int i;
 
     // update the flight model
@@ -466,50 +470,71 @@ void fgUpdateTimeDepCalcs(int multi_loop, int remainder) {
 	multi_loop = 1;
     }
 
+    fdm_state = cur_fdm_state;
+
     if ( !t->getPause() ) {
 	// run Autopilot system
 	fgAPRun();
 
 	// printf("updating flight model x %d\n", multi_loop);
 	fgFDMUpdate( current_options.get_flight_model(), 
-		     cur_fdm_state, 
+		     fdm_state, 
 		     multi_loop * current_options.get_speed_up(),
 		     remainder );
     } else {
 	fgFDMUpdate( current_options.get_flight_model(), 
-		     cur_fdm_state, 0, remainder );
+		     fdm_state, 0, remainder );
+    }
+
+    fdm_list.push_back( fdm_state );
+    while ( fdm_list.size() > 25 ) {
+	fdm_list.pop_front();
+    }
+
+    if ( current_options.get_view_mode() == fgOPTIONS::FG_VIEW_FIRST_PERSON ) {
+	cur_fdm_state = fdm_state;
+    } else if ( current_options.get_view_mode() == fgOPTIONS::FG_VIEW_FOLLOW ) {
+	cur_fdm_state = fdm_list.front();
     }
 
     // update the view angle
     for ( i = 0; i < multi_loop; i++ ) {
-	if ( fabs(v->get_goal_view_offset() - v->get_view_offset()) < 0.05 ) {
-	    v->set_view_offset( v->get_goal_view_offset() );
+	if ( fabs(current_view.get_goal_view_offset() - 
+		  current_view.get_view_offset()) < 0.05 )
+	{
+	    current_view.set_view_offset( current_view.get_goal_view_offset() );
 	    break;
 	} else {
-	    // move v->view_offset towards v->goal_view_offset
-	    if ( v->get_goal_view_offset() > v->get_view_offset() ) {
-		if ( v->get_goal_view_offset() - v->get_view_offset() < FG_PI ){
-		    v->inc_view_offset( 0.01 );
+	    // move current_view.view_offset towards current_view.goal_view_offset
+	    if ( current_view.get_goal_view_offset() > 
+		 current_view.get_view_offset() )
+            {
+		if ( current_view.get_goal_view_offset() - 
+		     current_view.get_view_offset() < FG_PI )
+                {
+		    current_view.inc_view_offset( 0.01 );
 		} else {
-		    v->inc_view_offset( -0.01 );
+		    current_view.inc_view_offset( -0.01 );
 		}
 	    } else {
-		if ( v->get_view_offset() - v->get_goal_view_offset() < FG_PI ){
-		    v->inc_view_offset( -0.01 );
+		if ( current_view.get_view_offset() - 
+		     current_view.get_goal_view_offset() < FG_PI )
+                {
+		    current_view.inc_view_offset( -0.01 );
 		} else {
-		    v->inc_view_offset( 0.01 );
+		    current_view.inc_view_offset( 0.01 );
 		}
 	    }
-	    if ( v->get_view_offset() > FG_2PI ) {
-		v->inc_view_offset( -FG_2PI );
-	    } else if ( v->get_view_offset() < 0 ) {
-		v->inc_view_offset( FG_2PI );
+	    if ( current_view.get_view_offset() > FG_2PI ) {
+		current_view.inc_view_offset( -FG_2PI );
+	    } else if ( current_view.get_view_offset() < 0 ) {
+		current_view.inc_view_offset( FG_2PI );
 	    }
 	}
     }
 
     double tmp = -(l->sun_rotation + FG_PI) 
-	- (f->get_Psi() - v->get_view_offset() );
+	- (cur_fdm_state.get_Psi() - current_view.get_view_offset() );
     while ( tmp < 0.0 ) {
 	tmp += FG_2PI;
     }
@@ -517,7 +542,7 @@ void fgUpdateTimeDepCalcs(int multi_loop, int remainder) {
 	tmp -= FG_2PI;
     }
     /* printf("Psi = %.2f, viewoffset = %.2f sunrot = %.2f rottosun = %.2f\n",
-	   FG_Psi * RAD_TO_DEG, v->view_offset * RAD_TO_DEG, 
+	   FG_Psi * RAD_TO_DEG, current_view.view_offset * RAD_TO_DEG, 
 	   -(l->sun_rotation+FG_PI) * RAD_TO_DEG, tmp * RAD_TO_DEG); */
     l->UpdateAdjFog();
 }
@@ -540,7 +565,6 @@ static const double alt_adjust_m = alt_adjust_ft * FEET_TO_METER;
 // What should we do when we have nothing else to do?  Let's get ready
 // for the next move and update the display?
 static void fgMainLoop( void ) {
-    FGInterface *f;
     FGTime *t;
     static long remainder = 0;
     long elapsed, multi_loop;
@@ -552,7 +576,6 @@ static void fgMainLoop( void ) {
     static int frames = 0;
 #endif // FANCY_FRAME_COUNTER
 
-    f = current_aircraft.fdm_state;
     t = FGTime::cur_time_params;
 
     FG_LOG( FG_ALL, FG_DEBUG, "Running Main Loop");
@@ -578,15 +601,15 @@ static void fgMainLoop( void ) {
 
     /* printf("Before - ground = %.2f  runway = %.2f  alt = %.2f\n",
 	   scenery.cur_elev,
-	   f->get_Runway_altitude() * FEET_TO_METER,
-	   f->get_Altitude() * FEET_TO_METER); */
+	   cur_fdm_state.get_Runway_altitude() * FEET_TO_METER,
+	   cur_fdm_state.get_Altitude() * FEET_TO_METER); */
 
     if ( scenery.cur_elev > -9990 ) {
-	if ( f->get_Altitude() * FEET_TO_METER < 
+	if ( cur_fdm_state.get_Altitude() * FEET_TO_METER < 
 	     (scenery.cur_elev + alt_adjust_m - 3.0) ) {
 	    // now set aircraft altitude above ground
 	    printf("Current Altitude = %.2f < %.2f forcing to %.2f\n", 
-		   f->get_Altitude() * FEET_TO_METER,
+		   cur_fdm_state.get_Altitude() * FEET_TO_METER,
 		   scenery.cur_elev + alt_adjust_m - 3.0,
 		   scenery.cur_elev + alt_adjust_m );
 	    fgFDMForceAltitude( current_options.get_flight_model(), 
@@ -594,7 +617,7 @@ static void fgMainLoop( void ) {
 
 	    FG_LOG( FG_ALL, FG_DEBUG, 
 		    "<*> resetting altitude to " 
-		    << f->get_Altitude() * FEET_TO_METER << " meters" );
+		    << cur_fdm_state.get_Altitude() * FEET_TO_METER << " meters" );
 	}
 	fgFDMSetGroundElevation( current_options.get_flight_model(),
 				 scenery.cur_elev );  // meters
@@ -602,11 +625,11 @@ static void fgMainLoop( void ) {
 
     /* printf("Adjustment - ground = %.2f  runway = %.2f  alt = %.2f\n",
 	   scenery.cur_elev,
-	   f->get_Runway_altitude() * FEET_TO_METER,
-	   f->get_Altitude() * FEET_TO_METER); */
+	   cur_fdm_state.get_Runway_altitude() * FEET_TO_METER,
+	   cur_fdm_state.get_Altitude() * FEET_TO_METER); */
 
     // update "time"
-    t->update(f);
+    t->update(cur_fdm_state);
 
     // Get elapsed time (in usec) for this past frame
     elapsed = fgGetTimeInterval();
@@ -695,16 +718,16 @@ static void fgMainLoop( void ) {
 
 	double pitch = log((controls.get_throttle(0) * 14.0) + 1.0);
 	//fprintf(stderr, "pitch1: %f ", pitch);
-	if (controls.get_throttle(0) > 0.0 || f->v_rel_wind > 40.0) {
-	    //fprintf(stderr, "rel_wind: %f ", f->v_rel_wind);
+	if (controls.get_throttle(0) > 0.0 || cur_fdm_state.v_rel_wind > 40.0) {
+	    //fprintf(stderr, "rel_wind: %f ", cur_fdm_state.v_rel_wind);
 	    // only add relative wind and AoA if prop is moving
 	    // or we're really flying at idle throttle
 	    if (pitch < 5.4) {  // this needs tuning
 		// prop tips not breaking sound barrier
-		pitch += log(f->v_rel_wind + 0.8)/2;
+		pitch += log(cur_fdm_state.v_rel_wind + 0.8)/2;
 	    } else {
 		// prop tips breaking sound barrier
-		pitch += log(f->v_rel_wind + 0.8)/10;
+		pitch += log(cur_fdm_state.v_rel_wind + 0.8)/10;
 	    }
 	    //fprintf(stderr, "pitch2: %f ", pitch);
 	    //fprintf(stderr, "AoA: %f ", FG_Gamma_vert_rad);
@@ -712,7 +735,7 @@ static void fgMainLoop( void ) {
 	    // Angle of Attack next... -x^3(e^x) is my best guess Just
 	    // need to calculate some reasonable scaling factor and
 	    // then clamp it on the positive aoa (neg adj) side
-	    double aoa = f->get_Gamma_vert_rad() * 2.2;
+	    double aoa = cur_fdm_state.get_Gamma_vert_rad() * 2.2;
 	    double tmp = 3.0;
 	    double aoa_adj = pow(-aoa, tmp) * pow(M_E, aoa);
 	    if (aoa_adj < -0.8) aoa_adj = -0.8;
@@ -726,7 +749,7 @@ static void fgMainLoop( void ) {
 	//fprintf(stderr, "pitch4: %f\n", pitch);
 
 	double volume = controls.get_throttle(0) * 1.15 + 0.3 +
-	    log(f->v_rel_wind + 1.0)/14.0;
+	    log(cur_fdm_state.v_rel_wind + 1.0)/14.0;
 	// fprintf(stderr, "volume: %f\n", volume);
 
 	pitch_envelope.setStep  ( 0, 0.01, pitch );
@@ -920,7 +943,7 @@ void fgReshape( int width, int height ) {
 	// yes we've finished all our initializations and are running
 	// the main loop, so this will now work without seg faulting
 	// the system.
-	current_view.UpdateViewParams();
+	current_view.UpdateViewParams(cur_fdm_state);
 	if ( current_options.get_panel_status() ) {
 	    FGPanel::OurPanel->ReInit(0, 0, 1024, 768);
 	}
diff --git a/src/Main/options.cxx b/src/Main/options.cxx
index 8f77381d7..889d5d0db 100644
--- a/src/Main/options.cxx
+++ b/src/Main/options.cxx
@@ -174,6 +174,7 @@ fgOPTIONS::fgOPTIONS() :
     wireframe(0),
     xsize(640),
     ysize(480),
+    view_mode(FG_VIEW_FIRST_PERSON),
 
     // Scenery options
     tile_diameter(5),
diff --git a/src/Main/options.hxx b/src/Main/options.hxx
index 6c2b89528..360a096ef 100644
--- a/src/Main/options.hxx
+++ b/src/Main/options.hxx
@@ -104,6 +104,12 @@ public:
 	FG_MOUSE = 2
     };
 
+    enum fgViewMode
+    {
+	FG_VIEW_FIRST_PERSON = 0,
+	FG_VIEW_FOLLOW  = 1
+    };
+
 private:
 
     // The flight gear "root" directory
@@ -148,6 +154,7 @@ private:
     bool textures;      // Textures enabled/disabled
     bool wireframe;     // Wireframe mode enabled/disabled
     int xsize, ysize;   // window size derived from geometry string
+    fgViewMode view_mode; // view mode
 
     // Scenery options
     int tile_radius;   // Square radius of rendered tiles (around center 
@@ -231,6 +238,7 @@ public:
     inline bool get_wireframe() const { return wireframe; }
     inline int get_xsize() const { return xsize; }
     inline int get_ysize() const { return ysize; }
+    inline fgViewMode get_view_mode() const { return view_mode; }
     inline int get_tile_radius() const { return tile_radius; }
     inline int get_tile_diameter() const { return tile_diameter; }
 
@@ -262,8 +270,16 @@ public:
 	}
     }
     void toggle_panel();
-    inline void set_xsize( int x ) { xsize= x; }
-    inline void set_ysize( int y ) { xsize= y; }
+    inline void set_xsize( int x ) { xsize = x; }
+    inline void set_ysize( int y ) { ysize = y; }
+    inline void cycle_view_mode() { 
+	if ( view_mode == FG_VIEW_FIRST_PERSON ) {
+	    view_mode = FG_VIEW_FOLLOW;
+	} else if ( view_mode == FG_VIEW_FOLLOW ) {
+	    view_mode = FG_VIEW_FIRST_PERSON;
+	}
+    }
+
     inline void set_net_id( const string id ) { net_id = id; }
 
 private:
diff --git a/src/Main/views.cxx b/src/Main/views.cxx
index 542db906d..2ca254219 100644
--- a/src/Main/views.cxx
+++ b/src/Main/views.cxx
@@ -62,7 +62,12 @@ static int panel_hist = 0;
 static const bool use_larcsim_local_to_body = false;
 
 
-// This is a record containing current view parameters
+// This is a record containing current view parameters for the current
+// aircraft position
+FGView pilot_view;
+
+// This is a record containing current view parameters for the current
+// view position
 FGView current_view;
 
 
@@ -75,7 +80,6 @@ FGView::FGView( void ) {
 void FGView::Init( void ) {
     FG_LOG( FG_VIEW, FG_INFO, "Initializing View parameters" );
 
-    view_mode = FG_VIEW_FIRST_PERSON;
     view_offset = 0.0;
     goal_view_offset = 0.0;
 
@@ -131,20 +135,8 @@ void FGView::UpdateFOV( const fgOPTIONS& o ) {
 }
 
 
-// Cycle view mode
-void FGView::cycle_view_mode() {
-    if ( view_mode == FG_VIEW_FIRST_PERSON ) {
-	view_mode = FG_VIEW_FOLLOW;
-    } else if ( view_mode == FG_VIEW_FOLLOW ) {
-	view_mode = FG_VIEW_FIRST_PERSON;
-    }
-}
-
-
 // Update the view volume, position, and orientation
-void FGView::UpdateViewParams( void ) {
-    FGInterface *f = current_aircraft.fdm_state;
-
+void FGView::UpdateViewParams( const FGInterface& f ) {
     UpdateViewMath(f);
     
     if ((current_options.get_panel_status() != panel_hist) &&                          (current_options.get_panel_status()))
@@ -281,7 +273,7 @@ void getRotMatrix(double* out, MAT3vec vec, double radians)
 
 
 // Update the view parameters
-void FGView::UpdateViewMath( FGInterface *f ) {
+void FGView::UpdateViewMath( const FGInterface& f ) {
     Point3D p;
     MAT3vec vec, forward, v0, minus_z;
     MAT3mat R, TMP, UP, LOCAL, VIEW;
@@ -300,18 +292,18 @@ void FGView::UpdateViewMath( FGInterface *f ) {
     //        scenery.center.y, scenery.center.z);
 
     // calculate the cartesion coords of the current lat/lon/0 elev
-    p = Point3D( f->get_Longitude(), 
-		 f->get_Lat_geocentric(), 
-		 f->get_Sea_level_radius() * FEET_TO_METER );
+    p = Point3D( f.get_Longitude(), 
+		 f.get_Lat_geocentric(), 
+		 f.get_Sea_level_radius() * FEET_TO_METER );
 
     cur_zero_elev = fgPolarToCart3d(p) - scenery.center;
 
     // calculate view position in current FG view coordinate system
     // p.lon & p.lat are already defined earlier, p.radius was set to
     // the sea level radius, so now we add in our altitude.
-    if ( f->get_Altitude() * FEET_TO_METER > 
+    if ( f.get_Altitude() * FEET_TO_METER > 
 	 (scenery.cur_elev + 0.5 * METER_TO_FEET) ) {
-	p.setz( p.radius() + f->get_Altitude() * FEET_TO_METER );
+	p.setz( p.radius() + f.get_Altitude() * FEET_TO_METER );
     } else {
 	p.setz( p.radius() + scenery.cur_elev + 0.5 * METER_TO_FEET );
     }
@@ -320,26 +312,26 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 	
 #else // FG_VIEW_INLINE_OPTIMIZATIONS
 	
-    double tmp_radius = f->get_Sea_level_radius() * FEET_TO_METER;
-    double tmp = f->get_cos_lat_geocentric() * tmp_radius;
+    double tmp_radius = f.get_Sea_level_radius() * FEET_TO_METER;
+    double tmp = f.get_cos_lat_geocentric() * tmp_radius;
 	
-    cur_zero_elev.setx(f->get_cos_longitude()*tmp - scenery.center.x());
-    cur_zero_elev.sety(f->get_sin_longitude()*tmp - scenery.center.y());
-    cur_zero_elev.setz(f->get_sin_lat_geocentric()*tmp_radius - scenery.center.z());
+    cur_zero_elev.setx(f.get_cos_longitude()*tmp - scenery.center.x());
+    cur_zero_elev.sety(f.get_sin_longitude()*tmp - scenery.center.y());
+    cur_zero_elev.setz(f.get_sin_lat_geocentric()*tmp_radius - scenery.center.z());
 
     // calculate view position in current FG view coordinate system
     // p.lon & p.lat are already defined earlier, p.radius was set to
     // the sea level radius, so now we add in our altitude.
-    if ( f->get_Altitude() * FEET_TO_METER > 
+    if ( f.get_Altitude() * FEET_TO_METER > 
 	 (scenery.cur_elev + 0.5 * METER_TO_FEET) ) {
-	tmp_radius += f->get_Altitude() * FEET_TO_METER;
+	tmp_radius += f.get_Altitude() * FEET_TO_METER;
     } else {
 	tmp_radius += scenery.cur_elev + 0.5 * METER_TO_FEET ;
     }
-    tmp = f->get_cos_lat_geocentric() * tmp_radius;
-    abs_view_pos.setx(f->get_cos_longitude()*tmp);
-    abs_view_pos.sety(f->get_sin_longitude()*tmp);
-    abs_view_pos.setz(f->get_sin_lat_geocentric()*tmp_radius);
+    tmp = f.get_cos_lat_geocentric() * tmp_radius;
+    abs_view_pos.setx(f.get_cos_longitude()*tmp);
+    abs_view_pos.sety(f.get_sin_longitude()*tmp);
+    abs_view_pos.setz(f.get_sin_lat_geocentric()*tmp_radius);
 	
 #endif // FG_VIEW_INLINE_OPTIMIZATIONS
 	
@@ -360,17 +352,17 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 	// Answer (I think): The LaRCsim matrix is generated in a
 	// different reference frame than we've set up for our world
 
-	LOCAL[0][0] = f->get_T_local_to_body_33();
-	LOCAL[0][1] = -f->get_T_local_to_body_32();
-	LOCAL[0][2] = -f->get_T_local_to_body_31();
+	LOCAL[0][0] = f.get_T_local_to_body_33();
+	LOCAL[0][1] = -f.get_T_local_to_body_32();
+	LOCAL[0][2] = -f.get_T_local_to_body_31();
 	LOCAL[0][3] = 0.0;
-	LOCAL[1][0] = -f->get_T_local_to_body_23();
-	LOCAL[1][1] = f->get_T_local_to_body_22();
-	LOCAL[1][2] = f->get_T_local_to_body_21();
+	LOCAL[1][0] = -f.get_T_local_to_body_23();
+	LOCAL[1][1] = f.get_T_local_to_body_22();
+	LOCAL[1][2] = f.get_T_local_to_body_21();
 	LOCAL[1][3] = 0.0;
-	LOCAL[2][0] = -f->get_T_local_to_body_13();
-	LOCAL[2][1] = f->get_T_local_to_body_12();
-	LOCAL[2][2] = f->get_T_local_to_body_11();
+	LOCAL[2][0] = -f.get_T_local_to_body_13();
+	LOCAL[2][1] = f.get_T_local_to_body_12();
+	LOCAL[2][2] = f.get_T_local_to_body_11();
 	LOCAL[2][3] = 0.0;
 	LOCAL[3][0] = LOCAL[3][1] = LOCAL[3][2] = LOCAL[3][3] = 0.0;
 	LOCAL[3][3] = 1.0;
@@ -411,18 +403,18 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 	// flight model
 
 	MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
-	MAT3rotate(R, vec, f->get_Phi());
+	MAT3rotate(R, vec, f.get_Phi());
 	// cout << "Roll matrix" << endl;
 	// MAT3print(R, stdout);
 
 	sgVec3 sgrollvec;
 	sgSetVec3( sgrollvec, 0.0, 0.0, 1.0 );
 	sgMat4 sgPHI;		// roll
-	sgMakeRotMat4( sgPHI, f->get_Phi() * RAD_TO_DEG, sgrollvec );
+	sgMakeRotMat4( sgPHI, f.get_Phi() * RAD_TO_DEG, sgrollvec );
 
 
 	MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
-	MAT3rotate(TMP, vec, f->get_Theta());
+	MAT3rotate(TMP, vec, f.get_Theta());
 	// cout << "Pitch matrix" << endl;;
 	// MAT3print(TMP, stdout);
 	MAT3mult(R, R, TMP);
@@ -432,7 +424,7 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 	sgVec3 sgpitchvec;
 	sgSetVec3( sgpitchvec, 0.0, 1.0, 0.0 );
 	sgMat4 sgTHETA;		// pitch
-	sgMakeRotMat4( sgTHETA, f->get_Theta() * RAD_TO_DEG,
+	sgMakeRotMat4( sgTHETA, f.get_Theta() * RAD_TO_DEG,
 		       sgpitchvec );
 
 	sgMat4 sgROT;
@@ -440,7 +432,7 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 
 
 	MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
-	MAT3rotate(TMP, vec, -f->get_Psi());
+	MAT3rotate(TMP, vec, -f.get_Psi());
 	// cout << "Yaw matrix" << endl;
 	// MAT3print(TMP, stdout);
 	MAT3mult(LOCAL, R, TMP);
@@ -450,7 +442,7 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 	sgVec3 sgyawvec;
 	sgSetVec3( sgyawvec, 1.0, 0.0, 0.0 );
 	sgMat4 sgPSI;		// pitch
-	sgMakeRotMat4( sgPSI, -f->get_Psi() * RAD_TO_DEG, sgyawvec );
+	sgMakeRotMat4( sgPSI, -f.get_Psi() * RAD_TO_DEG, sgyawvec );
 
 	sgMultMat4( sgLOCAL, sgROT, sgPSI );
 
@@ -472,13 +464,13 @@ void FGView::UpdateViewMath( FGInterface *f ) {
     // Derive the local UP transformation matrix based on *geodetic*
     // coordinates
     MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
-    MAT3rotate(R, vec, f->get_Longitude());     // R = rotate about Z axis
+    MAT3rotate(R, vec, f.get_Longitude());     // R = rotate about Z axis
     // printf("Longitude matrix\n");
     // MAT3print(R, stdout);
 
     MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
     MAT3mult_vec(vec, vec, R);
-    MAT3rotate(TMP, vec, -f->get_Latitude());  // TMP = rotate about X axis
+    MAT3rotate(TMP, vec, -f.get_Latitude());  // TMP = rotate about X axis
     // printf("Latitude matrix\n");
     // MAT3print(TMP, stdout);
 
@@ -487,9 +479,9 @@ void FGView::UpdateViewMath( FGInterface *f ) {
     // MAT3print(UP, stdout);
 
     sgMakeRotMat4( sgUP, 
-		   f->get_Longitude() * RAD_TO_DEG,
+		   f.get_Longitude() * RAD_TO_DEG,
 		   0.0,
-		   -f->get_Latitude() * RAD_TO_DEG );
+		   -f.get_Latitude() * RAD_TO_DEG );
     /*
     cout << "FG derived UP matrix using sg routines" << endl;
     MAT3mat print;
@@ -551,9 +543,9 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 
     sgMultMat4( sgVIEW, sgVIEW_ROT, sgTRANS );
 
-    FGMat4Wrapper tmp;
-    sgCopyMat4( tmp.m, sgVIEW );
-    follow.push_back( tmp );
+    // FGMat4Wrapper tmp;
+    // sgCopyMat4( tmp.m, sgVIEW );
+    // follow.push_back( tmp );
 
     // generate the current up, forward, and fwrd-view vectors
     MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
@@ -603,10 +595,10 @@ void FGView::UpdateViewMath( FGInterface *f ) {
 #else // FG_VIEW_INLINE_OPTIMIZATIONS
 	 
     //	// Build spherical to cartesian transform matrix directly
-    double cos_lat = f->get_cos_latitude(); // cos(-f->get_Latitude());
-    double sin_lat = -f->get_sin_latitude(); // sin(-f->get_Latitude());
-    double cos_lon = f->get_cos_longitude(); //cos(f->get_Longitude());
-    double sin_lon = f->get_sin_longitude(); //sin(f->get_Longitude());
+    double cos_lat = f.get_cos_latitude(); // cos(-f.get_Latitude());
+    double sin_lat = -f.get_sin_latitude(); // sin(-f.get_Latitude());
+    double cos_lon = f.get_cos_longitude(); //cos(f.get_Longitude());
+    double sin_lon = f.get_sin_longitude(); //sin(f.get_Longitude());
 
     double *mat = (double *)UP;
 	
diff --git a/src/Main/views.hxx b/src/Main/views.hxx
index 764f6fd2c..aee75ec80 100644
--- a/src/Main/views.hxx
+++ b/src/Main/views.hxx
@@ -46,14 +46,14 @@
 FG_USING_STD(list);
 
 
-class FGMat4Wrapper {
-public:
-    sgMat4 m;
-};
+// class FGMat4Wrapper {
+// public:
+//     sgMat4 m;
+// };
 
-typedef list < FGMat4Wrapper > sgMat4_list;
-typedef sgMat4_list::iterator sgMat4_list_iterator;
-typedef sgMat4_list::const_iterator const_sgMat4_list_iterator;
+// typedef list < FGMat4Wrapper > sgMat4_list;
+// typedef sgMat4_list::iterator sgMat4_list_iterator;
+// typedef sgMat4_list::const_iterator const_sgMat4_list_iterator;
 
 
 // used in views.cxx and tilemgr.cxx
@@ -65,12 +65,6 @@ class FGView {
 
 public:
 
-    enum fgViewMode
-    {
-	FG_VIEW_FIRST_PERSON = 0,
-	FG_VIEW_FOLLOW  = 1
-    };
-
     // the current offset from forward for viewing
     double view_offset;
 
@@ -166,14 +160,11 @@ public:
     // Current model view matrix;
     GLfloat MODEL_VIEW[16];
 
-    // view mode
-    fgViewMode view_mode;
-
     // sg versions of our friendly matrices
     sgMat4 sgLOCAL, sgUP, sgVIEW_ROT, sgTRANS, sgVIEW, sgLARC_TO_SSG;
 
     // queue of view matrices so we can have a follow view
-    sgMat4_list follow;
+    // sgMat4_list follow;
 
 public:
 
@@ -187,21 +178,18 @@ public:
     void Init( void );
 
     // Update the view volume, position, and orientation
-    void UpdateViewParams( void );
+    void UpdateViewParams( const FGInterface& f );
 
     // Flag to request that UpdateFOV() be called next time
     // UpdateViewMath() is run.
     inline void force_update_fov_math() { update_fov = true; }
 
     // Update the view parameters
-    void UpdateViewMath( FGInterface *f );
+    void UpdateViewMath( const FGInterface& f );
 
     // Update the field of view coefficients
     void UpdateFOV( const fgOPTIONS& o );
 
-    // Cycle view mode
-    void cycle_view_mode();
-
     // accessor functions
     inline double get_view_offset() const { return view_offset; }
     inline void set_view_offset( double a ) { view_offset = a; }
@@ -261,6 +249,7 @@ public:
 };
 
 
+extern FGView pilot_view;
 extern FGView current_view;