Support helipad names in the --runway startup option

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

diff --git a/src/Instrumentation/heading_indicator.cxx b/src/Instrumentation/heading_indicator.cxx
index dc939c5980e11d7bcf02f074608fb4421b704648..d95a1a0844488106d0b5cf42a3f49b905793cd98 100644 (file)
--- a/src/Instrumentation/heading_indicator.cxx
+++ b/src/Instrumentation/heading_indicator.cxx
@@ -3,12 +3,26 @@
 //
 // This file is in the Public Domain and comes with no warranty.
 
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include <simgear/compiler.h>
+#include <simgear/sg_inlines.h>
+#include <simgear/math/SGMath.hxx>
+#include <iostream>
+#include <string>
+#include <sstream>
+
 #include "heading_indicator.hxx"
 #include <Main/fg_props.hxx>
 #include <Main/util.hxx>
 
-
-HeadingIndicator::HeadingIndicator ()
+HeadingIndicator::HeadingIndicator ( SGPropertyNode *node )
+    :
+    _name(node->getStringValue("name", "heading-indicator")),
+    _num(node->getIntValue("number", 0)),
+    _suction(node->getStringValue("suction", "/systems/vacuum/suction-inhg"))
 {
 }
 
@@ -19,80 +33,99 @@ 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);
+    std::string branch;
+    branch = "/instrumentation/" + _name;
+
+    SGPropertyNode *node = fgGetNode(branch.c_str(), _num, true );
+    if( NULL == (_offset_node = node->getChild("offset-deg", 0, false)) ) {
+      _offset_node = node->getChild("offset-deg", 0, true);
+      _offset_node->setDoubleValue( -fgGetDouble("/environment/magnetic-variation-deg") );
+    }
     _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(_suction.c_str(), true);
+    _heading_out_node = node->getChild("indicated-heading-deg", 0, true);
+    _heading_bug_error_node = node->getChild("heading-bug-error-deg", 0, true);
+    _heading_bug_node = node->getChild("heading-bug-deg", 0, true);
+  
+    reinit();
+}
+
+void
+HeadingIndicator::reinit ()
+{
     _last_heading_deg = (_heading_in_node->getDoubleValue() +
                          _offset_node->getDoubleValue());
+    _gyro.reinit();
 }
 
 void
 HeadingIndicator::bind ()
 {
+    std::ostringstream temp;
+    std::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;
+    std::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();
     offset -= dt * (0.25 / 60.0); // 360deg/day
-    while (offset < -360)
-        offset += 360;
-    while (offset > 360)
-        offset -= 360;
-    _offset_node->setDoubleValue(offset);
+    SG_NORMALIZE_RANGE(offset, -360.0, 360.0);
 
                                 // TODO: movement-induced error
 
                                 // Next, calculate the indicated heading,
                                 // introducing errors.
-    double factor = 0.01 / (spin * spin * spin * spin * spin * spin);
+    double factor = 100 * (spin * spin * spin * spin * spin * spin);
     double heading = _heading_in_node->getDoubleValue();
-    heading = fgGetLowPass(_last_heading_deg, heading, dt/factor);
+
+                                // 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;
 
     heading += offset;
-    while (heading < 0)
-        heading += 360;
-    while (heading > 360)
-        heading -= 360;
+    SG_NORMALIZE_RANGE(heading, 0.0, 360.0);
 
     _heading_out_node->setDoubleValue(heading);
+
+    // Calculate heading bug error normalized to +/- 180.0
+    double heading_bug = _heading_bug_node->getDoubleValue();
+    double diff = heading_bug - heading;
+
+    SG_NORMALIZE_RANGE(diff, -180.0, 180.0);
+    _heading_bug_error_node->setDoubleValue( diff );
 }
 
 // end of heading_indicator.cxx