Make more use of SGGeod

[flightgear.git] / src / Instrumentation / heading_indicator.cxx

diff --git a/src/Instrumentation/heading_indicator.cxx b/src/Instrumentation/heading_indicator.cxx
index dc939c5980e11d7bcf02f074608fb4421b704648..4ab01a60f43115ca8cc5326266d86e567d0ce1bb 100644 (file)
--- a/src/Instrumentation/heading_indicator.cxx
+++ b/src/Instrumentation/heading_indicator.cxx
@@ -3,11 +3,42 @@
 //
 // This file is in the Public Domain and comes with no warranty.
 
+#include <simgear/compiler.h>
+#include STL_IOSTREAM
+#include STL_STRING
+#include <sstream>
+
 #include "heading_indicator.hxx"
 #include <Main/fg_props.hxx>
 #include <Main/util.hxx>
 
 
+HeadingIndicator::HeadingIndicator ( SGPropertyNode *node )
+    :
+    name("heading-indicator"),
+    num(0),
+    vacuum_system("/systems/vacuum")
+{
+    int i;
+    for ( i = 0; i < node->nChildren(); ++i ) {
+        SGPropertyNode *child = node->getChild(i);
+        string cname = child->getName();
+        string cval = child->getStringValue();
+        if ( cname == "name" ) {
+            name = cval;
+        } else if ( cname == "number" ) {
+            num = child->getIntValue();
+        } else if ( cname == "vacuum-system" ) {
+            vacuum_system = cval;
+        } else {
+            SG_LOG( SG_INSTR, SG_WARN, "Error in heading-indicator config logic" );
+            if ( name.length() ) {
+                SG_LOG( SG_INSTR, SG_WARN, "Section = " << name );
+            }
+        }
+    }
+}
+
 HeadingIndicator::HeadingIndicator ()
 {
 }
@@ -19,17 +50,15 @@ HeadingIndicator::~HeadingIndicator ()
 void
 HeadingIndicator::init ()
 {
-    _serviceable_node =
-        fgGetNode("/instrumentation/heading-indicator/serviceable", true);
-    _spin_node =
-        fgGetNode("/instrumentation/heading-indicator/spin", true);
-    _offset_node =
-        fgGetNode("/instrumentation/heading-indicator/offset-deg", true);
+    string branch;
+    branch = "/instrumentation/" + name;
+    vacuum_system += "/suction-inhg";
+
+    SGPropertyNode *node = fgGetNode(branch.c_str(), num, true );
+    _offset_node = node->getChild("offset-deg", 0, true);
     _heading_in_node = fgGetNode("/orientation/heading-deg", true);
-    _suction_node = fgGetNode("/systems/vacuum[0]/suction-inhg", true);
-    _heading_out_node =
-        fgGetNode("/instrumentation/heading-indicator/indicated-heading-deg",
-                  true);
+    _suction_node = fgGetNode(vacuum_system.c_str(), true);
+    _heading_out_node = node->getChild("indicated-heading-deg", 0, true);
     _last_heading_deg = (_heading_in_node->getDoubleValue() +
                          _offset_node->getDoubleValue());
 }
@@ -37,36 +66,36 @@ HeadingIndicator::init ()
 void
 HeadingIndicator::bind ()
 {
+    std::ostringstream temp;
+    string branch;
+    temp << num;
+    branch = "/instrumentation/" + name + "[" + temp.str() + "]";
+
+    fgTie((branch + "/serviceable").c_str(),
+          &_gyro, &Gyro::is_serviceable, &Gyro::set_serviceable);
+    fgTie((branch + "/spin").c_str(),
+          &_gyro, &Gyro::get_spin_norm, &Gyro::set_spin_norm);
 }
 
 void
 HeadingIndicator::unbind ()
 {
+    std::ostringstream temp;
+    string branch;
+    temp << num;
+    branch = "/instrumentation/" + name + "[" + temp.str() + "]";
+
+    fgUntie((branch + "/serviceable").c_str());
+    fgUntie((branch + "/spin").c_str());
 }
 
 void
 HeadingIndicator::update (double dt)
 {
-                                // First, calculate the bogo-spin from 0 to 1.
-                                // All numbers are made up.
-
-    double spin = _spin_node->getDoubleValue();
-    spin -= 0.005 * dt;         // spin decays every 0.5% every second.
-
-                                // spin increases up to 25% every second
-                                // if suction is available and the gauge
-                                // is serviceable.
-    if (_serviceable_node->getBoolValue()) {
-        double suction = _suction_node->getDoubleValue();
-        double step = 0.25 * (suction / 5.0) * dt;
-        if ((spin + step) <= (suction / 5.0))
-            spin += step;
-    }
-    if (spin > 1.0)
-        spin = 1.0;
-    else if (spin < 0.0)
-        spin = 0.0;
-    _spin_node->setDoubleValue(spin);
+                                // Get the spin from the gyro
+    _gyro.set_power_norm(_suction_node->getDoubleValue()/5.0);
+    _gyro.update(dt);
+    double spin = _gyro.get_spin_norm();
 
                                 // Next, calculate time-based precession
     double offset = _offset_node->getDoubleValue();
@@ -83,6 +112,15 @@ HeadingIndicator::update (double dt)
                                 // introducing errors.
     double factor = 0.01 / (spin * spin * spin * spin * spin * spin);
     double heading = _heading_in_node->getDoubleValue();
+
+                                // Now, we have to get the current
+                                // heading and the last heading into
+                                // the same range.
+    while ((heading - _last_heading_deg) > 180)
+        _last_heading_deg += 360;
+    while ((heading - _last_heading_deg) < -180)
+        _last_heading_deg -= 360;
+
     heading = fgGetLowPass(_last_heading_deg, heading, dt/factor);
     _last_heading_deg = heading;