Replace the data/Airports/basic.dat.gz and data/Airports/runways.dat.gz with

[flightgear.git] / src / AIModel / AIBase.cxx

diff --git a/src/AIModel/AIBase.cxx b/src/AIModel/AIBase.cxx
index 057f3bc84791f022a6502c3a0b232ebe40074ad5..b5459a38f2ffd8245a56ce7b29acb91ab0b5a63e 100644 (file)
--- a/src/AIModel/AIBase.cxx
+++ b/src/AIModel/AIBase.cxx
@@ -44,7 +44,7 @@
 #include "AIManager.hxx"
 
 
-const double FGAIBase::rho = 0.023780;  // sea level air density slugs/ft3
+const double FGAIBase::e = 2.71828183;
 const double FGAIBase::lbs_to_slugs = 0.031080950172;   //conversion factor
 
 
@@ -78,10 +78,42 @@ FGAIBase::~FGAIBase() {
 }
 
 void FGAIBase::update(double dt) {
-    ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.lat()/SG_RADIANS_TO_DEGREES);
-    ft_per_deg_lon = 365228.16 * cos(pos.lat() / SG_RADIANS_TO_DEGREES);
-}
+    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() {
     if (!invisible) {
@@ -104,7 +136,7 @@ bool FGAIBase::init() {
    props = root->getNode(_type_str.c_str(), index, true);
 
    if (model_path != "") {
-      model = sgLoad3DModel( globals->get_fg_root(),
+      model = load3DModel( globals->get_fg_root(),
                             model_path.c_str(),
                              props,
                             globals->get_sim_time_sec() );
@@ -125,6 +157,36 @@ bool FGAIBase::init() {
    return true;
 }
 
+
+ssgBranch * FGAIBase::load3DModel(const string& fg_root, 
+                                 const string &path,
+                                 SGPropertyNode *prop_root, 
+                                 double sim_time_sec)
+{
+  // some more code here to check whether a model with this name has already been loaded
+  // if not load it, otherwise, get the memory pointer and do something like 
+  // SetModel as in ATC/AIEntity.cxx
+  //SSGBranch *model;
+  model = manager->getModel(path);
+  if (!(model))
+    {
+      model = sgLoad3DModel(fg_root,
+                           path,
+                           prop_root,
+                           sim_time_sec);
+      manager->setModel(path, model);
+      model->ref();
+    }
+  //else
+  //  {
+  //    model->ref();
+  //    aip.init(model);
+  //    aip.setVisible(false);
+  //    globals->get_scenery()->get_scene_graph()->addKid(aip.getSceneGraph());
+  // do some setModel stuff.
+  return model;
+}
+
 bool FGAIBase::isa( object_type otype ) {
  if ( otype == _otype ) { return true; }
  else { return false; } 
@@ -171,6 +233,7 @@ void FGAIBase::bind() {
                SGRawValueFunctions<bool>(_isNight));
    props->setBoolValue("controls/lighting/beacon", true);
    props->setBoolValue("controls/lighting/strobe", true);
+   props->setBoolValue("controls/glide-path", true);
 }
 
 void FGAIBase::unbind() {