fix(Core/Movement): Improved fleeing movement generator. (#11896)

* fix(Core/Movement): Improved fleeing movement generator.

Fixes #11850

* Update.

src/server/game/Movement/MovementGenerators/FleeingMovementGenerator.cpp

@@ -26,6 +26,7 @@
 
 #define MIN_QUIET_DISTANCE 28.0f
 #define MAX_QUIET_DISTANCE 43.0f
+#define MIN_PATH_LENGTH 2.0f
 
 template<class T>
 void FleeingMovementGenerator<T>::DoInitialize(T* owner)
@@ -144,6 +145,20 @@ void FleeingMovementGenerator<T>::SetTargetLocation(T* owner)
         return;
     }
 
+    // Same position - recheck
+    if (_path->getPathLength() < MIN_PATH_LENGTH)
+    {
+        if (_fleeTargetGUID)
+        {
+            ++_shortPathsCount;
+        }
+
+        _timer.Reset(100);
+        return;
+    }
+
+    _shortPathsCount = 0;
+
     Movement::MoveSplineInit init(owner);
     init.MovebyPath(_path->GetPath());
     init.SetWalk(false);
@@ -154,8 +169,13 @@ void FleeingMovementGenerator<T>::SetTargetLocation(T* owner)
 template<class T>
 void FleeingMovementGenerator<T>::GetPoint(T* owner, Position& position)
 {
-    float casterDistance, casterAngle;
+    float casterDistance = 0.f;
-    if (Unit* fleeTarget = ObjectAccessor::GetUnit(*owner, _fleeTargetGUID))
+    float casterAngle = 0.f;
+    Unit* fleeTarget = nullptr;
+    if (_shortPathsCount < 5)
+        fleeTarget = ObjectAccessor::GetUnit(*owner, _fleeTargetGUID);
+
+    if (fleeTarget)
     {
         casterDistance = fleeTarget->GetDistance(owner);
         if (casterDistance > 0.2f)
@@ -173,7 +193,8 @@ void FleeingMovementGenerator<T>::GetPoint(T* owner, Position& position)
         casterAngle = frand(0.0f, 2.0f * float(M_PI));
     }
 
-    float distance, angle;
+    float distance = 0.f;
+    float angle = 0.f;
     if (casterDistance < MIN_QUIET_DISTANCE)
     {
         distance = frand(0.4f, 1.3f) * (MIN_QUIET_DISTANCE - casterDistance);

src/server/game/Movement/MovementGenerators/FleeingMovementGenerator.h

@@ -24,7 +24,7 @@ template<class T>
 class FleeingMovementGenerator : public MovementGeneratorMedium< T, FleeingMovementGenerator<T> >
 {
     public:
-        explicit FleeingMovementGenerator(ObjectGuid fleeTargetGUID) : _path(nullptr), _fleeTargetGUID(fleeTargetGUID), _timer(0), _interrupt(false) {}
+        explicit FleeingMovementGenerator(ObjectGuid fleeTargetGUID) : _path(nullptr), _fleeTargetGUID(fleeTargetGUID), _timer(0), _interrupt(false), _shortPathsCount(0) { }
 
         MovementGeneratorType GetMovementGeneratorType() override { return FLEEING_MOTION_TYPE; }
 
@@ -41,6 +41,7 @@ class FleeingMovementGenerator : public MovementGeneratorMedium< T, FleeingMovem
         ObjectGuid _fleeTargetGUID;
         TimeTracker _timer;
         bool _interrupt;
+        uint8 _shortPathsCount;
 };
 
 class TimedFleeingMovementGenerator : public FleeingMovementGenerator<Creature>