David Culp:

I added an AIStatic object to my OV-10 sim for use in putting city signs,
vehicles, or anything else that will be static, but that I don't want to put
in the scenery files.  It's inexpensive.  Before, I was making such things
from AIShip.

I also added the ability to set flight plans to repeat, so that when an
airplane reaches the end it just starts over at the beginning.  This is
useful for my OV-10 sim.  I have C-141 and KC-135 traffic flying approaches
to Ramstein, and I only have to define two AI objects to do this.

Also, I found an inefficiency in AIBase, where every AI object was calculating
Mach number at every dt.  Now only AIBallistic objects do this.

src/AIModel/AIAircraft.cxx

@@ -584,7 +584,12 @@ void FGAIAircraft::ProcessFlightPlan( double dt, time_t now )
     // Current waypoint's elevation according to Terrain Elevation
     if (curr->finished) {  //end of the flight plan
       {
-	setDie(true);
+         if (fp->getRepeat()) {
+           fp->restart();
+         } else {   
+ 	  setDie(true);
+         } 
+
 	//cerr << "Done die end of fp" << endl;
       }
       return;

src/AIModel/AIAircraft.hxx

@@ -61,6 +61,7 @@ public:
 
         void SetPerformance(const PERF_STRUCT *ps);
         void SetFlightPlan(FGAIFlightPlan *f);
+        FGAIFlightPlan* GetFlightPlan() { return fp; };
         void AccelTo(double speed);
         void PitchTo(double angle);
         void RollTo(double angle);

src/AIModel/AIBase.cxx

@@ -81,41 +81,11 @@ FGAIBase::~FGAIBase() {
 }
 
 void FGAIBase::update(double dt) {
+    if (_otype == otStatic) return;
+    if (_otype == otBallistic) CalculateMach();
+
     ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.lat()*SGD_DEGREES_TO_RADIANS);
     ft_per_deg_lon = 365228.16 * cos(pos.lat()*SGD_DEGREES_TO_RADIANS);
-
-    // Calculate rho at altitude, using standard atmosphere
-    // For the temperature T and the pressure p,
-
-    if (altitude < 36152) {		// curve fits for the troposphere
-      T = 59 - 0.00356 * altitude;
-      p = 2116 * pow( ((T + 459.7) / 518.6) , 5.256);
-
-    } else if ( 36152 < altitude && altitude < 82345 ) {    // lower stratosphere
-      T = -70;
-      p = 473.1 * pow( e , 1.73 - (0.000048 * altitude) );
-
-    } else {                                    //  upper stratosphere
-      T = -205.05 + (0.00164 * altitude);
-      p = 51.97 * pow( ((T + 459.7) / 389.98) , -11.388);
-    }
-
-    rho = p / (1718 * (T + 459.7));
-	
-	// calculate the speed of sound at altitude
-	// a = sqrt ( g * R * (T + 459.7))
-	// where:
-	// a = speed of sound [ft/s]
-	// g = specific heat ratio, which is usually equal to 1.4  
-	// R = specific gas constant, which equals 1716 ft-lb/slug/°R 
-	
-	a = sqrt ( 1.4 * 1716 * (T + 459.7));
-	
-	// calculate Mach number
-	
-	Mach = speed/a;
-	
-//	cout  << "Speed(ft/s) "<< speed <<" Altitude(ft) "<< altitude << " Mach " << Mach;
 }
 
 void FGAIBase::Transform() {
@@ -393,3 +363,39 @@ bool FGAIBase::_isNight() {
 int FGAIBase::_getID() const {
     return (int)(this);
 }
+
+void FGAIBase::CalculateMach() {
+     // Calculate rho at altitude, using standard atmosphere
+     // For the temperature T and the pressure p,
+ 
+     if (altitude < 36152) {		// curve fits for the troposphere
+       T = 59 - 0.00356 * altitude;
+       p = 2116 * pow( ((T + 459.7) / 518.6) , 5.256);
+ 
+     } else if ( 36152 < altitude && altitude < 82345 ) {    // lower stratosphere
+       T = -70;
+       p = 473.1 * pow( e , 1.73 - (0.000048 * altitude) );
+ 
+     } else {                                    //  upper stratosphere
+       T = -205.05 + (0.00164 * altitude);
+       p = 51.97 * pow( ((T + 459.7) / 389.98) , -11.388);
+     }
+ 
+     rho = p / (1718 * (T + 459.7));
+ 	
+ 	// calculate the speed of sound at altitude
+ 	// a = sqrt ( g * R * (T + 459.7))
+ 	// where:
+ 	// a = speed of sound [ft/s]
+ 	// g = specific heat ratio, which is usually equal to 1.4  
+ 	// R = specific gas constant, which equals 1716 ft-lb/slug/°R 
+ 	
+ 	a = sqrt ( 1.4 * 1716 * (T + 459.7));
+ 	
+ 	// calculate Mach number
+ 	
+ 	Mach = speed/a;
+ 	
+ //	cout  << "Speed(ft/s) "<< speed <<" Altitude(ft) "<< altitude << " Mach " << Mach;
+}
+

src/AIModel/AIBase.hxx

@@ -40,7 +40,7 @@ class FGAIFlightPlan;
 typedef struct {
    string callsign;
 
-   // can be aircraft, ship, storm, thermal or ballistic
+   // can be aircraft, ship, storm, thermal, static or ballistic
    string m_type;
    string m_class;
    string path;
@@ -93,7 +93,7 @@ public:
     inline Point3D GetPos() { return(pos); }
 
     enum object_type { otNull = 0, otAircraft, otShip, otCarrier, otBallistic,
-                       otRocket, otStorm, otThermal, 
+                       otRocket, otStorm, otThermal, otStatic,
                        MAX_OBJECTS };	// Needs to be last!!!
 
     virtual bool init();
@@ -167,7 +167,7 @@ protected:
     FGAIFlightPlan *fp;
 
     void Transform();
-
+    void CalculateMach();
     double UpdateRadar(FGAIManager* manager);
 
     string _type_str;

src/AIModel/AIFlightPlan.cxx

@@ -50,6 +50,7 @@ FGAIFlightPlan::FGAIFlightPlan(string filename)
   SGPath path( globals->get_fg_root() );
   path.append( ("/Data/AI/FlightPlans/" + filename).c_str() );
   SGPropertyNode root;
+  repeat = false;
 
   try {
       readProperties(path.str(), &root);
@@ -472,3 +473,9 @@ void FGAIFlightPlan::resetWaypoints()
       waypoints.push_back(wpt);
     }
 }
+
+// Start flightplan over from the beginning
+void FGAIFlightPlan::restart()
+{
+  wpt_iterator = waypoints.begin();
+}

src/AIModel/AIFlightPlan.hxx

@@ -85,18 +85,23 @@ public:
   double getLeadInAngle() { return leadInAngle; };
   string getRunway() { return rwy._rwy_no; };
   string getRunwayId() { return rwy._id; };
+  void setRepeat(bool r) { repeat = r; };
+  bool getRepeat(void) { return repeat; };
+  void restart(void);
+
 private:
   FGRunway rwy;
-    typedef vector <waypoint*> wpt_vector_type;
+  typedef vector <waypoint*> wpt_vector_type;
-    typedef wpt_vector_type::iterator wpt_vector_iterator;
+  typedef wpt_vector_type::iterator wpt_vector_iterator;
 
-    wpt_vector_type       waypoints;
+  wpt_vector_type       waypoints;
-    wpt_vector_iterator   wpt_iterator;
+  wpt_vector_iterator   wpt_iterator;
 
-    double distance_to_go;
+  bool repeat;
-    double lead_distance;
+  double distance_to_go;
+  double lead_distance;
   double leadInAngle;
-    time_t start_time;
+   time_t start_time;
   int leg;
   int gateId;
 

src/AIModel/AIManager.cxx

@@ -36,6 +36,7 @@
 #include "AIStorm.hxx"
 #include "AIThermal.hxx"
 #include "AICarrier.hxx"
+#include "AIStatic.hxx"
 
 SG_USING_STD(list);
 
@@ -176,7 +177,9 @@ FGAIManager::createAircraft( FGAIModelEntity *entity,   FGAISchedule *ref) {
         if ( entity->fp ) {
           ai_plane->SetFlightPlan(entity->fp);
         }
-
+        if (entity->repeat) {
+          ai_plane->GetFlightPlan()->setRepeat(true);
+        }
         ai_plane->init();
         ai_plane->bind();
         return ai_plane;
@@ -310,6 +313,25 @@ FGAIManager::createThermal( FGAIModelEntity *entity ) {
         return ai_thermal;
 }
 
+void*
+FGAIManager::createStatic( FGAIModelEntity *entity ) {
+     
+     // cout << "creating static object" << endl;    
+
+        FGAIStatic* ai_static = new FGAIStatic(this);
+        ai_list.push_back(ai_static);
+        ++numObjects[0];
+        ++numObjects[FGAIBase::otStatic];
+        ai_static->setHeading(entity->heading);
+        ai_static->setPath(entity->path.c_str());
+        ai_static->setAltitude(entity->altitude);
+        ai_static->setLongitude(entity->longitude);
+        ai_static->setLatitude(entity->latitude);
+        ai_static->init();
+        ai_static->bind();
+        return ai_static;
+}
+
 void FGAIManager::destroyObject( void* ID ) {
         ai_list_iterator ai_list_itr = ai_list.begin();
         while(ai_list_itr != ai_list.end()) {
@@ -371,7 +393,10 @@ void FGAIManager::processScenario( string &filename ) {
 
       } else if ( en->m_type == "ballistic") {
         createBallistic( en );
-      }      
+
+      } else if ( en->m_type == "static") {
+        createStatic( en );
+      }            
     }
   }
 

src/AIModel/AIManager.hxx

@@ -1,4 +1,4 @@
-// AIManager.hxx - experimental! - David Culp - based on:
+// AIManager.hxx - David Culp - based on:
 // AIMgr.hxx - definition of FGAIMgr 
 // - a global management class for FlightGear generated AI traffic
 //
@@ -87,6 +87,7 @@ public:
     void* createStorm( FGAIModelEntity *entity );
     void* createShip( FGAIModelEntity *entity );
     void* createCarrier( FGAIModelEntity *entity );
+    void* createStatic( FGAIModelEntity *entity );
 
     void destroyObject( void* ID );
 

src/AIModel/AIStatic.cxx

@@ -0,0 +1,65 @@
+// FGAIStatic - FGAIBase-derived class creates an AI static object
+//
+// Written by David Culp, started Jun 2005.
+//
+// Copyright (C) 2005  David P. Culp - davidculp2@comcast.net
+//
+// 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.
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include <simgear/math/point3d.hxx>
+#include <Main/fg_props.hxx>
+#include <Main/globals.hxx>
+#include <Scenery/scenery.hxx>
+#include <string>
+#include <math.h>
+
+SG_USING_STD(string);
+
+#include "AIStatic.hxx"
+
+
+FGAIStatic::FGAIStatic(FGAIManager* mgr) {
+   manager = mgr;   
+   _type_str = "static";
+   _otype = otStatic;
+}
+
+
+FGAIStatic::~FGAIStatic() {
+}
+
+
+bool FGAIStatic::init() {
+   return FGAIBase::init();
+}
+
+void FGAIStatic::bind() {
+    FGAIBase::bind();
+}
+
+void FGAIStatic::unbind() {
+    FGAIBase::unbind();
+}
+
+
+void FGAIStatic::update(double dt) {
+   FGAIBase::update(dt);
+   Transform();
+}
+

src/AIModel/AIStatic.hxx

@@ -0,0 +1,51 @@
+// FGAIStatic - AIBase derived class creates AI static object
+//
+// Written by David Culp, started Jun 2005.
+//
+// Copyright (C) 2005  David P. Culp - davidculp2@comcast.net
+//
+// 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.
+
+#ifndef _FG_AIStatic_HXX
+#define _FG_AIStatic_HXX
+
+#include "AIManager.hxx"
+#include "AIBase.hxx"
+
+#include <string>
+SG_USING_STD(string);
+
+
+class FGAIStatic : public FGAIBase {
+
+public:
+
+	FGAIStatic(FGAIManager* mgr);
+	~FGAIStatic();
+	
+	bool init();
+        virtual void bind();
+        virtual void unbind();
+	void update(double dt);
+
+private:
+
+        double dt; 
+	
+};
+
+
+
+#endif  // _FG_AISTATIC_HXX

src/AIModel/Makefile.am

@@ -11,6 +11,7 @@ libAIModel_a_SOURCES = \
 	AIThermal.hxx AIThermal.cxx \
 	AIFlightPlan.hxx AIFlightPlan.cxx AIFlightPlanCreate.cxx \
 	AIScenario.hxx AIScenario.cxx \
-        AICarrier.hxx AICarrier.cxx
+        AICarrier.hxx AICarrier.cxx \
+        AIStatic.hxx AIStatic.cxx
 
 INCLUDES = -I$(top_srcdir) -I$(top_srcdir)/src