Event input: button fire repeat

src/Input/FGEventInput.cxx

@@ -190,7 +190,7 @@ void FGAxisEvent::fire( FGEventData & eventData )
       ed.value = interpolater->interpolate(ed.value);
     }
   }
-    
+
   FGInputEvent::fire( ed );
 }
 
@@ -242,6 +242,15 @@ void FGButtonEvent::fire( FGEventData & eventData )
   lastState = pressed;
 }
 
+void FGButtonEvent::update( double dt )
+{
+  if (repeatable && lastState) {
+      // interval / dt handling is done by base ::fire method
+      FGEventData ed{1.0, dt, 0 /* modifiers */};
+      FGInputEvent::fire( ed );
+  }
+}
+
 FGInputDevice::~FGInputDevice()
 {
   FGNasalSys *nas = (FGNasalSys *)globals->get_subsystem("nasal");

src/Input/FGEventInput.hxx

@@ -175,6 +175,7 @@ public:
   FGButtonEvent( FGInputDevice * device, SGPropertyNode_ptr node );
   virtual void fire( FGEventData & eventData );
 
+  void update( double dt ) override;
 protected:
   bool repeatable;
   bool lastState;