Heading Indicator DG: Same behaviour as introduced to turn-indicator: use previous default power path unless <new-default-power-path> is set to 1, then follow the common naming scheme. Also set spin property again (was broken by my previous changes)

src/Instrumentation/heading_indicator_dg.cxx

@@ -29,7 +29,9 @@ HeadingIndicatorDG::HeadingIndicatorDG ( SGPropertyNode *node ) :
     _last_heading_deg(0),
     _last_indicated_heading_dg(0)
 {
-    _powerSupplyPath = "/systems/electrical/outputs/DG[" + std::to_string( node->getIntValue("number", 0) ) + "]";
+    if( !node->getBoolValue("new-default-power-path", 0) ){
+       setDefaultPowerSupplyPath("/systems/electrical/outputs/DG");
+    }
     readConfig(node, "heading-indicator-dg");
 }
 
@@ -53,6 +55,7 @@ HeadingIndicatorDG::init ()
     _nav1_error_node        = node->getChild("nav1-course-error-deg", 0, true);
     _heading_out_node       = node->getChild("indicated-heading-deg", 0, true);
     _align_node             = node->getChild("align-deg", 0, true);
+    _spin_node              = node->getChild("spin", 0, true);
 
     initServicePowerProperties(node);
 
@@ -85,6 +88,8 @@ HeadingIndicatorDG::update (double dt)
     double spin = _gyro.get_spin_norm();
     double heading = _heading_in_node->getDoubleValue();
     double offset = _offset_node->getDoubleValue();
+    
+    _spin_node->setDoubleValue( spin );
 
     // calculate scaling factor
     double factor = POW6(spin);

src/Instrumentation/heading_indicator_dg.hxx

@@ -31,6 +31,17 @@
  * Output properties:
  *
  * /instrumentation/"name"/indicated-heading-deg
+ * 
+ * 
+ * Configuration:
+ * 
+ *   name
+ *   number
+ *   new-default-power-path: use /systems/electrical/outputs/"name"[ number ] instead of 
+ *                           /systems/electrical/outputs/DG as the default power
+ *                           supply path (not used when power-supply is set)
+ *   power-supply
+ *   minimum-supply-volts
  */
 class HeadingIndicatorDG : public AbstractInstrument
 {
@@ -64,4 +75,5 @@ private:
     SGPropertyNode_ptr _yaw_rate_node;
     SGPropertyNode_ptr _heading_bug_error_node;
     SGPropertyNode_ptr _g_node;
+    SGPropertyNode_ptr _spin_node;
 };

src/Instrumentation/heading_indicator_fg.cxx

@@ -54,6 +54,7 @@ HeadingIndicatorFG::init ()
     _nav1_error_node = node->getChild("nav1-course-error-deg", 0, true);
     _heading_out_node = node->getChild("indicated-heading-deg", 0, true);
     _off_node         = node->getChild("off-flag", 0, true);
+    _spin_node              = node->getChild("spin", 0, true);
 
     initServicePowerProperties(node);
 
@@ -75,6 +76,7 @@ HeadingIndicatorFG::update (double dt)
 	 _gyro.set_power_norm(isServiceableAndPowered());
 	_gyro.update(dt);
     double spin = _gyro.get_spin_norm();
+    _spin_node->setDoubleValue( spin );
 
     if ( isServiceableAndPowered() && spin >= 0.25) {
         _off_node->setBoolValue(false);

src/Instrumentation/heading_indicator_fg.hxx

@@ -64,4 +64,5 @@ private:
     SGPropertyNode_ptr _error_node;
     SGPropertyNode_ptr _nav1_error_node;
     SGPropertyNode_ptr _off_node;
+    SGPropertyNode_ptr _spin_node;
 };