diff --git a/Core/Code/Interactions/mitkMousePressEvent.cpp b/Core/Code/Interactions/mitkMousePressEvent.cpp
index b571666e4b..e8fdff0887 100644
--- a/Core/Code/Interactions/mitkMousePressEvent.cpp
+++ b/Core/Code/Interactions/mitkMousePressEvent.cpp
@@ -1,75 +1,75 @@
 /*===================================================================
 
  The Medical Imaging Interaction Toolkit (MITK)
 
  Copyright (c) German Cancer Research Center,
  Division of Medical and Biological Informatics.
  All rights reserved.
 
  This software is distributed WITHOUT ANY WARRANTY; without
  even the implied warranty of MERCHANTABILITY or FITNESS FOR
  A PARTICULAR PURPOSE.
 
  See LICENSE.txt or http://www.mitk.org for details.
 
  ===================================================================*/
 
 #include "mitkException.h"
 #include "mitkMousePressEvent.h"
 
-mitk::MousePressEvent::MousePressEvent(mitk::BaseRenderer* baseRenderer = NULL,
-    mitk::Point2D mousePosition = NULL,
-    mitk::MouseButtons buttonStates = NoButton,
-    mitk::ModifierKeys modifiers = NoKey,
-    mitk::MouseButtons eventButton = NoButton)
+mitk::MousePressEvent::MousePressEvent(mitk::BaseRenderer* baseRenderer,
+    mitk::Point2D mousePosition,
+    mitk::MouseButtons buttonStates,
+    mitk::ModifierKeys modifiers,
+    mitk::MouseButtons eventButton)
 : InteractionPositionEvent(baseRenderer, mousePosition, "MousePressEvent")
 , m_EventButton(eventButton)
 , m_ButtonStates(buttonStates)
 , m_Modifiers( modifiers)
 {
 }
 
 mitk::MouseButtons mitk::MousePressEvent::GetEventButton() const
 {
   return m_EventButton;
 }
 
 void mitk::MousePressEvent::SetEventButton(MouseButtons buttons)
 {
   m_EventButton = buttons;
 }
 
 mitk::ModifierKeys mitk::MousePressEvent::GetModifiers() const
 {
   return m_Modifiers;
 }
 
 mitk::MouseButtons mitk::MousePressEvent::GetButtonStates() const
 {
   return m_ButtonStates;
 }
 
 void mitk::MousePressEvent::SetModifiers(ModifierKeys modifiers)
 {
   m_Modifiers = modifiers;
 }
 
 void mitk::MousePressEvent::SetButtonStates(MouseButtons buttons)
 {
   m_ButtonStates = buttons;
 }
 
 mitk::MousePressEvent::~MousePressEvent()
 {
 }
 
 bool mitk::MousePressEvent::MatchesTemplate(mitk::InteractionEvent::Pointer interactionEvent)
 {
   mitk::MousePressEvent* mpe = dynamic_cast<mitk::MousePressEvent*>(interactionEvent.GetPointer());
   if (mpe == NULL)
   {
     return false;
   }
   return (this->GetEventButton() == mpe->GetEventButton() && this->GetModifiers() == mpe->GetModifiers()
       && this->GetButtonStates() == mpe->GetButtonStates());
 }
diff --git a/Core/Code/Interactions/mitkMouseReleaseEvent.cpp b/Core/Code/Interactions/mitkMouseReleaseEvent.cpp
index 9a17417dca..a9bebdb8bb 100644
--- a/Core/Code/Interactions/mitkMouseReleaseEvent.cpp
+++ b/Core/Code/Interactions/mitkMouseReleaseEvent.cpp
@@ -1,78 +1,78 @@
 /*===================================================================
 
  The Medical Imaging Interaction Toolkit (MITK)
 
  Copyright (c) German Cancer Research Center,
  Division of Medical and Biological Informatics.
  All rights reserved.
 
  This software is distributed WITHOUT ANY WARRANTY; without
  even the implied warranty of MERCHANTABILITY or FITNESS FOR
  A PARTICULAR PURPOSE.
 
  See LICENSE.txt or http://www.mitk.org for details.
 
  ===================================================================*/
 
 #include "mitkException.h"
 #include "mitkMouseReleaseEvent.h"
 
-mitk::MouseReleaseEvent::MouseReleaseEvent(mitk::BaseRenderer* baseRenderer = NULL,
-    mitk::Point2D mousePosition = NULL,
-    mitk::MouseButtons buttonStates = NoButton,
-    mitk::ModifierKeys modifiers = NoKey,
-    mitk::MouseButtons eventButton = NoButton)
+mitk::MouseReleaseEvent::MouseReleaseEvent(mitk::BaseRenderer* baseRenderer,
+    mitk::Point2D mousePosition,
+    mitk::MouseButtons buttonStates,
+    mitk::ModifierKeys modifiers,
+    mitk::MouseButtons eventButton)
 : InteractionPositionEvent(baseRenderer, mousePosition, "MouseReleaseEvent")
 , m_EventButton(eventButton)
 ,m_ButtonStates(buttonStates)
 , m_Modifiers(modifiers)
 {
 }
 
 mitk::MouseButtons mitk::MouseReleaseEvent::GetEventButton() const
 {
   return m_EventButton;
 }
 
 void mitk::MouseReleaseEvent::SetEventButton(MouseButtons buttons)
 {
   m_EventButton = buttons;
 }
 
 
 mitk::ModifierKeys mitk::MouseReleaseEvent::GetModifiers() const
 {
   return m_Modifiers;
 }
 
 mitk::MouseButtons mitk::MouseReleaseEvent::GetButtonStates() const
 {
   return m_ButtonStates;
 }
 
 void mitk::MouseReleaseEvent::SetModifiers(ModifierKeys modifiers)
 {
   m_Modifiers = modifiers;
 }
 
 void mitk::MouseReleaseEvent::SetButtonStates(MouseButtons buttons)
 {
   m_ButtonStates = buttons;
 }
 
 mitk::MouseReleaseEvent::~MouseReleaseEvent()
 {
 }
 
 bool mitk::MouseReleaseEvent::MatchesTemplate(mitk::InteractionEvent::Pointer interactionEvent)
 {
   mitk::MouseReleaseEvent* mre = dynamic_cast<mitk::MouseReleaseEvent*>(interactionEvent.GetPointer());
   if (mre == NULL)
   {
     return false;
   }
   return (this->GetEventButton() == mre->GetEventButton() && this->GetModifiers() == mre->GetModifiers()
       && this->GetButtonStates() == mre->GetButtonStates()
 
   );
 }
diff --git a/Core/Code/Interactions/mitkMouseWheelEvent.cpp b/Core/Code/Interactions/mitkMouseWheelEvent.cpp
index 146cfd06ca..b97968007a 100644
--- a/Core/Code/Interactions/mitkMouseWheelEvent.cpp
+++ b/Core/Code/Interactions/mitkMouseWheelEvent.cpp
@@ -1,74 +1,74 @@
 /*===================================================================
 
  The Medical Imaging Interaction Toolkit (MITK)
 
  Copyright (c) German Cancer Research Center,
  Division of Medical and Biological Informatics.
  All rights reserved.
 
  This software is distributed WITHOUT ANY WARRANTY; without
  even the implied warranty of MERCHANTABILITY or FITNESS FOR
  A PARTICULAR PURPOSE.
 
  See LICENSE.txt or http://www.mitk.org for details.
 
  ===================================================================*/
 
 #include "mitkMouseWheelEvent.h"
 
-mitk::MouseWheelEvent::MouseWheelEvent(BaseRenderer* baseRenderer = NULL,
-    Point2D mousePosition = NULL,
-    MouseButtons buttonStates = NoButton,
-    ModifierKeys modifiers = NoKey,
-    int wheelDelta = 0)
+mitk::MouseWheelEvent::MouseWheelEvent(BaseRenderer* baseRenderer,
+    Point2D mousePosition,
+    MouseButtons buttonStates,
+    ModifierKeys modifiers,
+    int wheelDelta)
 : InteractionPositionEvent(baseRenderer, mousePosition, "MouseWheelEvent")
 , m_WheelDelta(wheelDelta)
 , m_ButtonStates(buttonStates)
 , m_Modifiers(modifiers)
 {
 }
 
 int mitk::MouseWheelEvent::GetWheelDelta() const
 {
   return m_WheelDelta;
 }
 
 void mitk::MouseWheelEvent::SetWheelDelta(int delta)
 {
   m_WheelDelta = delta;
 }
 
 mitk::ModifierKeys mitk::MouseWheelEvent::GetModifiers() const
 {
   return m_Modifiers;
 }
 
 mitk::MouseButtons mitk::MouseWheelEvent::GetButtonStates() const
 {
   return m_ButtonStates;
 }
 
 void mitk::MouseWheelEvent::SetModifiers(ModifierKeys modifiers)
 {
   m_Modifiers = modifiers;
 }
 
 void mitk::MouseWheelEvent::SetButtonStates(MouseButtons buttons)
 {
   m_ButtonStates = buttons;
 }
 
 mitk::MouseWheelEvent::~MouseWheelEvent()
 {
 }
 
 bool mitk::MouseWheelEvent::MatchesTemplate(mitk::InteractionEvent::Pointer interactionEvent)
 {
   const mitk::MouseWheelEvent* mwe = dynamic_cast<const MouseWheelEvent*>(interactionEvent.GetPointer());
   if (mwe == NULL)
   {
     return false;
   }
   return ((this->GetWheelDelta() * mwe->GetWheelDelta() > 0) // Consider WheelEvents to be equal if the scrolling is done in the same direction.
   && this->GetModifiers() == mwe->GetModifiers() && this->GetButtonStates() == mwe->GetButtonStates());
 }