diff --git a/Engine/source/T3D/aiPlayer.cpp b/Engine/source/T3D/aiPlayer.cpp
index 630d4619c..b43d8c209 100644
--- a/Engine/source/T3D/aiPlayer.cpp
+++ b/Engine/source/T3D/aiPlayer.cpp
@@ -259,7 +259,7 @@ void AIPlayer::setAimObject( GameBase *targetObject )
  * @param targetObject The object to target
  * @param offset       The offest from the target location to aim at
  */
-void AIPlayer::setAimObject( GameBase *targetObject, Point3F offset )
+void AIPlayer::setAimObject(GameBase *targetObject, const Point3F& offset)
 {
    mAimObject = targetObject;
    mTargetInLOS = false;
diff --git a/Engine/source/T3D/aiPlayer.h b/Engine/source/T3D/aiPlayer.h
index cff90d549..3d11d4cbb 100644
--- a/Engine/source/T3D/aiPlayer.h
+++ b/Engine/source/T3D/aiPlayer.h
@@ -161,7 +161,7 @@ public:
 
    // Targeting and aiming sets/gets
    void setAimObject( GameBase *targetObject );
-   void setAimObject( GameBase *targetObject, Point3F offset );
+   void setAimObject(GameBase *targetObject, const Point3F& offset);
    GameBase* getAimObject() const  { return mAimObject; }
    void setAimLocation( const Point3F &location );
    Point3F getAimLocation() const { return mAimLocation; }
diff --git a/Engine/source/T3D/camera.cpp b/Engine/source/T3D/camera.cpp
index 637e68ab0..027bd308f 100644
--- a/Engine/source/T3D/camera.cpp
+++ b/Engine/source/T3D/camera.cpp
@@ -393,7 +393,7 @@ void Camera::getEyeCameraTransform(IDisplayDevice *displayDevice, U32 eyeId, Mat
    }
 }
 
-DisplayPose Camera::calcCameraDeltaPose(GameConnection *con, DisplayPose inPose)
+DisplayPose Camera::calcCameraDeltaPose(GameConnection *con, const DisplayPose& inPose)
 {
    // NOTE: this is intended to be similar to updateMove
    DisplayPose outPose;
diff --git a/Engine/source/T3D/camera.h b/Engine/source/T3D/camera.h
index 07f4caeb7..6e835d982 100644
--- a/Engine/source/T3D/camera.h
+++ b/Engine/source/T3D/camera.h
@@ -237,7 +237,7 @@ class Camera: public ShapeBase
       virtual void interpolateTick( F32 delta);
       virtual void getCameraTransform( F32* pos,MatrixF* mat );
       virtual void getEyeCameraTransform( IDisplayDevice *display, U32 eyeId, MatrixF *outMat );
-      virtual DisplayPose calcCameraDeltaPose(GameConnection *con, DisplayPose inPose);
+      virtual DisplayPose calcCameraDeltaPose(GameConnection *con, const DisplayPose& inPose);
 
       virtual void writePacketData( GameConnection* conn, BitStream* stream );
       virtual void readPacketData( GameConnection* conn, BitStream* stream );
diff --git a/Engine/source/T3D/fx/fxFoliageReplicator.cpp b/Engine/source/T3D/fx/fxFoliageReplicator.cpp
index 7e88b174f..51e044756 100644
--- a/Engine/source/T3D/fx/fxFoliageReplicator.cpp
+++ b/Engine/source/T3D/fx/fxFoliageReplicator.cpp
@@ -248,7 +248,7 @@ fxFoliageCulledList::fxFoliageCulledList(Box3F SearchBox, fxFoliageCulledList* I
 
 //------------------------------------------------------------------------------
 
-void fxFoliageCulledList::FindCandidates(Box3F SearchBox, fxFoliageCulledList* InVec)
+void fxFoliageCulledList::FindCandidates(const Box3F& SearchBox, fxFoliageCulledList* InVec)
 {
    // Search the Culled List.
    for (U32 i = 0; i < InVec->GetListCount(); i++)
@@ -1028,7 +1028,7 @@ void fxFoliageReplicator::SetupBuffers()
 
 //------------------------------------------------------------------------------
 
-Box3F fxFoliageReplicator::FetchQuadrant(Box3F Box, U32 Quadrant)
+Box3F fxFoliageReplicator::FetchQuadrant(const Box3F& Box, U32 Quadrant)
 {
    Box3F QuadrantBox;
 
diff --git a/Engine/source/T3D/fx/fxFoliageReplicator.h b/Engine/source/T3D/fx/fxFoliageReplicator.h
index deaac64cb..e40554454 100644
--- a/Engine/source/T3D/fx/fxFoliageReplicator.h
+++ b/Engine/source/T3D/fx/fxFoliageReplicator.h
@@ -86,7 +86,7 @@ public:
    fxFoliageCulledList(Box3F SearchBox, fxFoliageCulledList* InVec);
    ~fxFoliageCulledList() {};
 
-   void FindCandidates(Box3F SearchBox, fxFoliageCulledList* InVec);
+   void FindCandidates(const Box3F& SearchBox, fxFoliageCulledList* InVec);
 
    U32 GetListCount(void) { return mCulledObjectSet.size(); };
    fxFoliageItem* GetElement(U32 index) { return mCulledObjectSet[index]; };
@@ -157,7 +157,7 @@ protected:
 
    void SyncFoliageReplicators(void);
 
-   Box3F FetchQuadrant(Box3F Box, U32 Quadrant);
+   Box3F FetchQuadrant(const Box3F& Box, U32 Quadrant);
    void ProcessQuadrant(fxFoliageQuadrantNode* pParentNode, fxFoliageCulledList* pCullList, U32 Quadrant);
    void ProcessNodeChildren(fxFoliageQuadrantNode* pParentNode, fxFoliageCulledList* pCullList);
 
diff --git a/Engine/source/T3D/player.cpp b/Engine/source/T3D/player.cpp
index de95a4da9..3c258c374 100644
--- a/Engine/source/T3D/player.cpp
+++ b/Engine/source/T3D/player.cpp
@@ -5586,7 +5586,7 @@ void Player::getMuzzleTransform(U32 imageSlot,MatrixF* mat)
    *mat = nmat;
 }
 
-DisplayPose Player::calcCameraDeltaPose(GameConnection *con, DisplayPose inPose)
+DisplayPose Player::calcCameraDeltaPose(GameConnection *con, const DisplayPose& inPose)
 {
    // NOTE: this is intended to be similar to updateMove
    DisplayPose outPose;
diff --git a/Engine/source/T3D/player.h b/Engine/source/T3D/player.h
index 7eebee1c1..eb1a39443 100644
--- a/Engine/source/T3D/player.h
+++ b/Engine/source/T3D/player.h
@@ -684,7 +684,7 @@ public:
    void getEyeBaseTransform(MatrixF* mat, bool includeBank);
    void getRenderEyeTransform(MatrixF* mat);
    void getRenderEyeBaseTransform(MatrixF* mat, bool includeBank);
-   virtual DisplayPose calcCameraDeltaPose(GameConnection *con, DisplayPose inPose);
+   virtual DisplayPose calcCameraDeltaPose(GameConnection *con, const DisplayPose& inPose);
    void getCameraParameters(F32 *min, F32 *max, Point3F *offset, MatrixF *rot);
    void getMuzzleTransform(U32 imageSlot,MatrixF* mat);
    void getRenderMuzzleTransform(U32 imageSlot,MatrixF* mat);   
diff --git a/Engine/source/T3D/shapeBase.cpp b/Engine/source/T3D/shapeBase.cpp
index 61d766768..608695357 100644
--- a/Engine/source/T3D/shapeBase.cpp
+++ b/Engine/source/T3D/shapeBase.cpp
@@ -1192,13 +1192,13 @@ void ShapeBase::onDeleteNotify( SimObject *obj )
    Parent::onDeleteNotify( obj );      
 }
 
-void ShapeBase::onImpact(SceneObject* obj, VectorF vec)
+void ShapeBase::onImpact(SceneObject* obj, const VectorF& vec)
 {
    if (!isGhost())
       mDataBlock->onImpact_callback( this, obj, vec, vec.len() );
 }
 
-void ShapeBase::onImpact(VectorF vec)
+void ShapeBase::onImpact(const VectorF& vec)
 {
    if (!isGhost())
       mDataBlock->onImpact_callback( this, NULL, vec, vec.len() );
@@ -1995,7 +1995,7 @@ void ShapeBase::getEyeCameraTransform(IDisplayDevice *displayDevice, U32 eyeId,
    *outMat = temp;
 }
 
-DisplayPose ShapeBase::calcCameraDeltaPose(GameConnection *con, DisplayPose inPose)
+DisplayPose ShapeBase::calcCameraDeltaPose(GameConnection *con, const DisplayPose& inPose)
 {
    // NOTE: this is intended to be similar to updateMove
    // WARNING: does not take into account any move values
diff --git a/Engine/source/T3D/shapeBase.h b/Engine/source/T3D/shapeBase.h
index e3b18b196..797e93395 100644
--- a/Engine/source/T3D/shapeBase.h
+++ b/Engine/source/T3D/shapeBase.h
@@ -1103,8 +1103,8 @@ protected:
    virtual void shakeCamera( U32 imageSlot );
    virtual void updateDamageLevel();
    virtual void updateDamageState();
-   virtual void onImpact(SceneObject* obj, VectorF vec);
-   virtual void onImpact(VectorF vec);
+   virtual void onImpact(SceneObject* obj, const VectorF& vec);
+   virtual void onImpact(const VectorF& vec);
    /// @}
 
    /// The inner prep render function that does the 
@@ -1587,7 +1587,7 @@ public:
    virtual void getEyeCameraTransform( IDisplayDevice *display, U32 eyeId, MatrixF *outMat );
 
    /// Calculates a delta camera angle and view position based on inPose
-   virtual DisplayPose calcCameraDeltaPose(GameConnection *con, DisplayPose inPose);
+   virtual DisplayPose calcCameraDeltaPose(GameConnection *con, const DisplayPose& inPose);
 
    /// Gets the index of a node inside a mounted image given the name
    /// @param   imageSlot   Image slot
diff --git a/Engine/source/collision/boxConvex.cpp b/Engine/source/collision/boxConvex.cpp
index 48bcbbe13..298fc50bb 100644
--- a/Engine/source/collision/boxConvex.cpp
+++ b/Engine/source/collision/boxConvex.cpp
@@ -76,7 +76,7 @@ Point3F BoxConvex::getVertex(S32 v)
    return p;
 }
 
-inline bool isOnPlane(Point3F p,PlaneF& plane)
+inline bool isOnPlane(const Point3F& p,PlaneF& plane)
 {
    F32 dist = mDot(plane,p) + plane.d;
    return dist < 0.1 && dist > -0.1;
diff --git a/Engine/source/environment/editors/guiMeshRoadEditorCtrl.cpp b/Engine/source/environment/editors/guiMeshRoadEditorCtrl.cpp
index 10fdbe115..117b30ff9 100644
--- a/Engine/source/environment/editors/guiMeshRoadEditorCtrl.cpp
+++ b/Engine/source/environment/editors/guiMeshRoadEditorCtrl.cpp
@@ -1091,7 +1091,7 @@ F32 GuiMeshRoadEditorCtrl::getNodeDepth()
    return 0.0f;
 }
 
-void GuiMeshRoadEditorCtrl::setNodePosition( Point3F pos )
+void GuiMeshRoadEditorCtrl::setNodePosition(const Point3F& pos)
 {
    if ( mSelRoad && mSelNode != -1 )
    {
diff --git a/Engine/source/environment/editors/guiMeshRoadEditorCtrl.h b/Engine/source/environment/editors/guiMeshRoadEditorCtrl.h
index 9e810982a..3109c538b 100644
--- a/Engine/source/environment/editors/guiMeshRoadEditorCtrl.h
+++ b/Engine/source/environment/editors/guiMeshRoadEditorCtrl.h
@@ -100,7 +100,7 @@ class GuiMeshRoadEditorCtrl : public EditTSCtrl
       void setNodeDepth( F32 depth );
 		
 		Point3F getNodePosition();
-		void setNodePosition( Point3F pos );
+      void setNodePosition(const Point3F& pos);
 
       VectorF getNodeNormal();
       void setNodeNormal( const VectorF &normal );
diff --git a/Engine/source/environment/editors/guiRiverEditorCtrl.cpp b/Engine/source/environment/editors/guiRiverEditorCtrl.cpp
index 44f161232..d7f86d10c 100644
--- a/Engine/source/environment/editors/guiRiverEditorCtrl.cpp
+++ b/Engine/source/environment/editors/guiRiverEditorCtrl.cpp
@@ -1235,7 +1235,7 @@ F32 GuiRiverEditorCtrl::getNodeDepth()
    return 0.0f;
 }
 
-void GuiRiverEditorCtrl::setNodePosition( Point3F pos )
+void GuiRiverEditorCtrl::setNodePosition(const Point3F& pos)
 {
    if ( mSelRiver && mSelNode != -1 )
    {
diff --git a/Engine/source/environment/editors/guiRiverEditorCtrl.h b/Engine/source/environment/editors/guiRiverEditorCtrl.h
index 978f6ed86..d8aa2efb5 100644
--- a/Engine/source/environment/editors/guiRiverEditorCtrl.h
+++ b/Engine/source/environment/editors/guiRiverEditorCtrl.h
@@ -110,7 +110,7 @@ class GuiRiverEditorCtrl : public EditTSCtrl
       void setNodeDepth( F32 depth );
 
 		Point3F getNodePosition();
-		void setNodePosition( Point3F pos );
+      void setNodePosition(const Point3F& pos);
 
 		VectorF getNodeNormal();
       void setNodeNormal( const VectorF &normal );
diff --git a/Engine/source/environment/editors/guiRoadEditorCtrl.cpp b/Engine/source/environment/editors/guiRoadEditorCtrl.cpp
index 1eecfb5ae..167a5db45 100644
--- a/Engine/source/environment/editors/guiRoadEditorCtrl.cpp
+++ b/Engine/source/environment/editors/guiRoadEditorCtrl.cpp
@@ -979,7 +979,7 @@ F32 GuiRoadEditorCtrl::getNodeWidth()
    return 0.0f;   
 }
 
-void GuiRoadEditorCtrl::setNodePosition( Point3F pos )
+void GuiRoadEditorCtrl::setNodePosition(const Point3F& pos)
 {
    if ( mSelRoad && mSelNode != -1 )
    {
diff --git a/Engine/source/environment/editors/guiRoadEditorCtrl.h b/Engine/source/environment/editors/guiRoadEditorCtrl.h
index c87a0fd53..f6383e548 100644
--- a/Engine/source/environment/editors/guiRoadEditorCtrl.h
+++ b/Engine/source/environment/editors/guiRoadEditorCtrl.h
@@ -97,7 +97,7 @@ class GuiRoadEditorCtrl : public EditTSCtrl
       void setNodeWidth( F32 width );
 
 		Point3F getNodePosition();
-		void setNodePosition( Point3F pos );
+      void setNodePosition(const Point3F& pos);
 
       void setTextureFile( StringTableEntry file );
 	
diff --git a/Engine/source/gfx/gfxDevice.cpp b/Engine/source/gfx/gfxDevice.cpp
index 9f9b7ecad..c72c109d0 100644
--- a/Engine/source/gfx/gfxDevice.cpp
+++ b/Engine/source/gfx/gfxDevice.cpp
@@ -735,14 +735,14 @@ void GFXDevice::setLight(U32 stage, GFXLightInfo* light)
 //-----------------------------------------------------------------------------
 // Set Light Material
 //-----------------------------------------------------------------------------
-void GFXDevice::setLightMaterial(GFXLightMaterial mat)
+void GFXDevice::setLightMaterial(const GFXLightMaterial& mat)
 {
    mCurrentLightMaterial = mat;
    mLightMaterialDirty = true;
    mStateDirty = true;
 }
 
-void GFXDevice::setGlobalAmbientColor(ColorF color)
+void GFXDevice::setGlobalAmbientColor(const ColorF& color)
 {
    if(mGlobalAmbientColor != color)
    {
diff --git a/Engine/source/gfx/gfxDevice.h b/Engine/source/gfx/gfxDevice.h
index 61c1a562f..b9ff01e8c 100644
--- a/Engine/source/gfx/gfxDevice.h
+++ b/Engine/source/gfx/gfxDevice.h
@@ -901,8 +901,8 @@ public:
    /// because of the state caching stuff.
    /// @{
    void setLight(U32 stage, GFXLightInfo* light);
-   void setLightMaterial(GFXLightMaterial mat);
-   void setGlobalAmbientColor(ColorF color);
+   void setLightMaterial(const GFXLightMaterial& mat);
+   void setGlobalAmbientColor(const ColorF& color);
 
    /// @}
    
diff --git a/Engine/source/gui/containers/guiContainer.h b/Engine/source/gui/containers/guiContainer.h
index b441e2d50..b7ead281e 100644
--- a/Engine/source/gui/containers/guiContainer.h
+++ b/Engine/source/gui/containers/guiContainer.h
@@ -91,7 +91,7 @@ class  GuiContainer : public GuiControl
       inline void setAnchorRight(bool val) { mSizingOptions.mAnchorRight = val; }
 
       ControlSizing getSizingOptions() const { return mSizingOptions; }
-      void setSizingOptions(ControlSizing val) { mSizingOptions = val; }
+      void setSizingOptions(const ControlSizing& val) { mSizingOptions = val; }
 
       /// @}   
 
diff --git a/Engine/source/gui/containers/guiSplitContainer.cpp b/Engine/source/gui/containers/guiSplitContainer.cpp
index cf6cab46e..df52829dc 100644
--- a/Engine/source/gui/containers/guiSplitContainer.cpp
+++ b/Engine/source/gui/containers/guiSplitContainer.cpp
@@ -444,7 +444,7 @@ bool GuiSplitContainer::layoutControls( RectI &clientRect )
 
 //-----------------------------------------------------------------------------
 
-void GuiSplitContainer::solvePanelConstraints( Point2I newDragPos, GuiContainer * firstPanel, GuiContainer * secondPanel, RectI clientRect )
+void GuiSplitContainer::solvePanelConstraints(Point2I newDragPos, GuiContainer * firstPanel, GuiContainer * secondPanel, const RectI& clientRect)
 {
    if( !firstPanel || !secondPanel )
       return;
diff --git a/Engine/source/gui/containers/guiSplitContainer.h b/Engine/source/gui/containers/guiSplitContainer.h
index 9e0bb0afe..f3d853fe4 100644
--- a/Engine/source/gui/containers/guiSplitContainer.h
+++ b/Engine/source/gui/containers/guiSplitContainer.h
@@ -84,7 +84,7 @@ public:
    virtual inline Point2I getSplitPoint() { return mSplitPoint; };
    /// The Splitters entire Client Rectangle, this takes into account padding of this control
    virtual inline RectI getSplitRect() { return mSplitRect; };
-   virtual void solvePanelConstraints( Point2I newDragPos, GuiContainer * firstPanel, GuiContainer * secondPanel, RectI clientRect );   
+   virtual void solvePanelConstraints(Point2I newDragPos, GuiContainer * firstPanel, GuiContainer * secondPanel, const RectI& clientRect);
    virtual Point2I getMinExtent() const;   
 
 protected:
diff --git a/Engine/source/gui/containers/guiTabBookCtrl.cpp b/Engine/source/gui/containers/guiTabBookCtrl.cpp
index d4dd4db43..1dae98eb5 100644
--- a/Engine/source/gui/containers/guiTabBookCtrl.cpp
+++ b/Engine/source/gui/containers/guiTabBookCtrl.cpp
@@ -548,7 +548,7 @@ void GuiTabBookCtrl::renderTabs( const Point2I &offset, const RectI &tabRect )
 
 //-----------------------------------------------------------------------------
 
-void GuiTabBookCtrl::renderTab( RectI tabRect, GuiTabPageCtrl *tab )
+void GuiTabBookCtrl::renderTab(const RectI& tabRect, GuiTabPageCtrl *tab)
 {
    StringTableEntry text = tab->getText();
    ColorI oldColor;
diff --git a/Engine/source/gui/containers/guiTabBookCtrl.h b/Engine/source/gui/containers/guiTabBookCtrl.h
index b8c7f3787..21b8c05da 100644
--- a/Engine/source/gui/containers/guiTabBookCtrl.h
+++ b/Engine/source/gui/containers/guiTabBookCtrl.h
@@ -158,7 +158,7 @@ class GuiTabBookCtrl : public GuiContainer
       /// Tab rendering subroutine, renders one tab with specified options
       /// @param   tabRect   the rectangle to render the tab into
       /// @param   tab   pointer to the tab page control for which to render the tab
-      void renderTab( RectI tabRect, GuiTabPageCtrl* tab );
+      void renderTab(const RectI& tabRect, GuiTabPageCtrl* tab);
 
       /// @}
 
diff --git a/Engine/source/gui/controls/guiGradientCtrl.cpp b/Engine/source/gui/controls/guiGradientCtrl.cpp
index 081b62382..53f10d65e 100644
--- a/Engine/source/gui/controls/guiGradientCtrl.cpp
+++ b/Engine/source/gui/controls/guiGradientCtrl.cpp
@@ -521,7 +521,7 @@ void GuiGradientCtrl::reInitSwatches( GuiGradientCtrl::PickMode )
 	}
 }
 
-void GuiGradientCtrl::addColorRange( Point2I pos, ColorF color )
+void GuiGradientCtrl::addColorRange(Point2I pos, const ColorF& color)
 {
 	if( pos.x + mSwatchFactor < mBlendRangeBox.point.x &&
 		pos.x + mSwatchFactor > mBlendRangeBox.extent.x )
diff --git a/Engine/source/gui/controls/guiGradientCtrl.h b/Engine/source/gui/controls/guiGradientCtrl.h
index fbbebdd0f..3d569f57e 100644
--- a/Engine/source/gui/controls/guiGradientCtrl.h
+++ b/Engine/source/gui/controls/guiGradientCtrl.h
@@ -148,7 +148,7 @@ public:
 	void inspectPreApply();
 	void inspectPostApply();
 	void reInitSwatches( GuiGradientCtrl::PickMode );
-	void addColorRange( Point2I pos, ColorF color );
+   void addColorRange(Point2I pos, const ColorF& color);
 	void removeColorRange( GuiGradientSwatchCtrl* swatch );
 	void sortColorRange();
 
diff --git a/Engine/source/gui/controls/guiListBoxCtrl.cpp b/Engine/source/gui/controls/guiListBoxCtrl.cpp
index c5b50a94f..296c7e158 100644
--- a/Engine/source/gui/controls/guiListBoxCtrl.cpp
+++ b/Engine/source/gui/controls/guiListBoxCtrl.cpp
@@ -677,7 +677,7 @@ DefineEngineMethod( GuiListBoxCtrl, setItemColor, void, (S32 index, ColorF color
    object->setItemColor( index, color );
 }
 
-void GuiListBoxCtrl::setItemColor( S32 index, ColorF color )
+void GuiListBoxCtrl::setItemColor(S32 index, const ColorF& color)
 {
    if ((index >= mItems.size()) || index < 0)
    {
@@ -1090,7 +1090,7 @@ void GuiListBoxCtrl::onRender( Point2I offset, const RectI &updateRect )
    GFX->setClipRect( oldClipRect );
 }
 
-void GuiListBoxCtrl::onRenderItem( RectI itemRect, LBItem *item )
+void GuiListBoxCtrl::onRenderItem(const RectI& itemRect, LBItem *item)
 {
    if( item->isSelected )
       GFX->getDrawUtil()->drawRectFill( itemRect, mProfile->mFillColorSEL );
diff --git a/Engine/source/gui/controls/guiListBoxCtrl.h b/Engine/source/gui/controls/guiListBoxCtrl.h
index 016e4ac63..7c03edf9f 100644
--- a/Engine/source/gui/controls/guiListBoxCtrl.h
+++ b/Engine/source/gui/controls/guiListBoxCtrl.h
@@ -107,7 +107,7 @@ public:
    S32               insertItemWithColor( S32 index, StringTableEntry text, ColorF color = ColorF(-1, -1, -1), void *itemData = NULL);
    S32               findItemText( StringTableEntry text, bool caseSensitive = false );
 
-   void              setItemColor(S32 index, ColorF color);
+   void              setItemColor(S32 index, const ColorF& color);
    void              clearItemColor(S32 index);
 
    void              deleteItem( S32 index );
@@ -128,7 +128,7 @@ public:
 
    // Rendering
    virtual void      onRender( Point2I offset, const RectI &updateRect );
-   virtual void      onRenderItem( RectI itemRect, LBItem *item );
+   virtual void      onRenderItem(const RectI& itemRect, LBItem *item);
    void              drawBox( const Point2I &box, S32 size, ColorI &outlineColor, ColorI &boxColor );
    bool              renderTooltip( const Point2I &hoverPos, const Point2I& cursorPos, const char* tipText );
 	void					addFilteredItem( String item );
diff --git a/Engine/source/gui/editor/guiMenuBar.cpp b/Engine/source/gui/editor/guiMenuBar.cpp
index aeabdca30..59bd7271b 100644
--- a/Engine/source/gui/editor/guiMenuBar.cpp
+++ b/Engine/source/gui/editor/guiMenuBar.cpp
@@ -1623,7 +1623,7 @@ void GuiMenuBar::closeMenu()
 }
 
 //  Called when a menu item is highlighted by the mouse
-void GuiMenuBar::highlightedMenuItem(S32 selectionIndex, RectI bounds, Point2I cellSize)
+void GuiMenuBar::highlightedMenuItem(S32 selectionIndex, const RectI& bounds, Point2I cellSize)
 {
    S32 selstore = selectionIndex;
 
@@ -1777,7 +1777,7 @@ void GuiMenuBar::onAction()
 
 //------------------------------------------------------------------------------
 //  Performs an action when a menu item that is a submenu is selected/highlighted
-void GuiMenuBar::onSubmenuAction(S32 selectionIndex, RectI bounds, Point2I cellSize)
+void GuiMenuBar::onSubmenuAction(S32 selectionIndex, const RectI& bounds, Point2I cellSize)
 {
    if(!mouseOverSubmenu)
       return;
diff --git a/Engine/source/gui/editor/guiMenuBar.h b/Engine/source/gui/editor/guiMenuBar.h
index 7bf64d109..a6dfeb6fd 100644
--- a/Engine/source/gui/editor/guiMenuBar.h
+++ b/Engine/source/gui/editor/guiMenuBar.h
@@ -182,12 +182,12 @@ public:
    static void addSubmenuItem(Menu *menu, MenuItem *submenu, MenuItem *newMenuItem );
    static void removeSubmenuItem(MenuItem *menuItem, MenuItem *submenuItem);
    static void clearSubmenuItems(MenuItem *menuitem);
-   void onSubmenuAction(S32 selectionIndex, RectI bounds, Point2I cellSize);
+   void onSubmenuAction(S32 selectionIndex, const RectI& bounds, Point2I cellSize);
    void closeSubmenu();
    void checkSubmenuMouseMove(const GuiEvent &event);
    MenuItem *findHitMenuItem(Point2I mousePoint);
 
-   void highlightedMenuItem(S32 selectionIndex, RectI bounds, Point2I cellSize); //  Called whenever a menu item is highlighted by the mouse
+   void highlightedMenuItem(S32 selectionIndex, const RectI& bounds, Point2I cellSize); //  Called whenever a menu item is highlighted by the mouse
 
 	// display/mouse functions
 
diff --git a/Engine/source/gui/worldEditor/guiDecalEditorCtrl.cpp b/Engine/source/gui/worldEditor/guiDecalEditorCtrl.cpp
index 3370da07c..bf0bb6628 100644
--- a/Engine/source/gui/worldEditor/guiDecalEditorCtrl.cpp
+++ b/Engine/source/gui/worldEditor/guiDecalEditorCtrl.cpp
@@ -918,7 +918,7 @@ void DICreateUndoAction::initPersistFields()
    Parent::initPersistFields();
 }
 
-void DICreateUndoAction::addDecal( DecalInstance decal )
+void DICreateUndoAction::addDecal(const DecalInstance& decal)
 {
 	mDecalInstance = decal;
 	mDatablockId = decal.mDataBlock->getId();
@@ -1006,7 +1006,7 @@ void DIDeleteUndoAction::initPersistFields()
    Parent::initPersistFields();
 }
 
-void DIDeleteUndoAction::deleteDecal( DecalInstance decal )
+void DIDeleteUndoAction::deleteDecal(const DecalInstance& decal)
 {
 	mDecalInstance = decal;
 	mDatablockId = decal.mDataBlock->getId();
@@ -1094,7 +1094,7 @@ void DBDeleteUndoAction::initPersistFields()
    Parent::initPersistFields();
 }
 
-void DBDeleteUndoAction::deleteDecal( DecalInstance decal )
+void DBDeleteUndoAction::deleteDecal(const DecalInstance& decal)
 {
 	mDecalInstanceVec.increment();
    mDecalInstanceVec.last() = decal;
diff --git a/Engine/source/gui/worldEditor/guiDecalEditorCtrl.h b/Engine/source/gui/worldEditor/guiDecalEditorCtrl.h
index 043634a5d..06903e049 100644
--- a/Engine/source/gui/worldEditor/guiDecalEditorCtrl.h
+++ b/Engine/source/gui/worldEditor/guiDecalEditorCtrl.h
@@ -129,7 +129,7 @@ public:
    DICreateUndoAction( const UTF8* actionName = "Create Decal " );
    virtual ~DICreateUndoAction();
 
-   void addDecal( DecalInstance decal );
+   void addDecal(const DecalInstance& decal);
 
    // UndoAction
    virtual void undo();
@@ -159,7 +159,7 @@ public:
    virtual ~DIDeleteUndoAction();
 
    ///
-   void deleteDecal( DecalInstance decal );
+   void deleteDecal(const DecalInstance& decal);
 
    // UndoAction
    virtual void undo();
@@ -188,7 +188,7 @@ public:
    DBDeleteUndoAction( const UTF8* actionName = "Delete Decal Datablock" );
    virtual ~DBDeleteUndoAction();
 
-   void deleteDecal( DecalInstance decal );
+   void deleteDecal(const DecalInstance& decal);
 
    // UndoAction
    virtual void undo();
diff --git a/Engine/source/navigation/navMesh.cpp b/Engine/source/navigation/navMesh.cpp
index d708c65e7..a6e957d46 100644
--- a/Engine/source/navigation/navMesh.cpp
+++ b/Engine/source/navigation/navMesh.cpp
@@ -681,7 +681,7 @@ void NavMesh::updateConfig()
    cfg.tileSize = mTileSize / cfg.cs;
 }
 
-S32 NavMesh::getTile(Point3F pos)
+S32 NavMesh::getTile(const Point3F& pos)
 {
    if(mBuilding)
       return -1;
diff --git a/Engine/source/navigation/navMesh.h b/Engine/source/navigation/navMesh.h
index 6fd8d65bf..1d9eba1b1 100644
--- a/Engine/source/navigation/navMesh.h
+++ b/Engine/source/navigation/navMesh.h
@@ -118,7 +118,7 @@ public:
    /// @}
 
    /// Return the index of the tile included by this point.
-   S32 getTile(Point3F pos);
+   S32 getTile(const Point3F& pos);
 
    /// Return the box of a given tile.
    Box3F getTileBox(U32 id);
diff --git a/Engine/source/navigation/torqueRecast.h b/Engine/source/navigation/torqueRecast.h
index e703e6349..0d19fe92c 100644
--- a/Engine/source/navigation/torqueRecast.h
+++ b/Engine/source/navigation/torqueRecast.h
@@ -28,11 +28,11 @@
 #include "math/mBox.h"
 
 inline Point3F DTStoRC(F32 x, F32 y, F32 z) { return Point3F(x, z, -y); }
-inline Point3F DTStoRC(Point3F point)       { return Point3F(point.x, point.z, -point.y); }
+inline Point3F DTStoRC(const Point3F& point)       { return Point3F(point.x, point.z, -point.y); }
 inline Point3F RCtoDTS(const F32* xyz)      { return Point3F(xyz[0], -xyz[2], xyz[1]); }
 inline Point3F RCtoDTS(F32 x, F32 y, F32 z) { return Point3F(x, -z, y); }
-inline Point3F RCtoDTS(Point3F point)       { return Point3F(point.x, -point.z, point.y); }
-inline Box3F DTStoRC(Box3F box)
+inline Point3F RCtoDTS(const Point3F& point)       { return Point3F(point.x, -point.z, point.y); }
+inline Box3F DTStoRC(const Box3F& box)
 {
    return Box3F(box.minExtents.x, box.minExtents.z, -box.maxExtents.y,
                   box.maxExtents.x, box.maxExtents.z, -box.minExtents.y);
diff --git a/Engine/source/terrain/terrData.cpp b/Engine/source/terrain/terrData.cpp
index eeee6b008..356e5140b 100644
--- a/Engine/source/terrain/terrData.cpp
+++ b/Engine/source/terrain/terrData.cpp
@@ -339,7 +339,7 @@ bool TerrainBlock::setFile( const FileName &terrFileName )
    return true;
 }
 
-void TerrainBlock::setFile( Resource<TerrainFile> terr )
+void TerrainBlock::setFile(const Resource<TerrainFile>& terr)
 {
    mFile = terr;
    mTerrFileName = terr.getPath();
diff --git a/Engine/source/terrain/terrData.h b/Engine/source/terrain/terrData.h
index 91618df73..2982de3e9 100644
--- a/Engine/source/terrain/terrData.h
+++ b/Engine/source/terrain/terrData.h
@@ -413,7 +413,7 @@ public:
 
    bool setFile( const FileName& terrFileName );
 
-   void setFile( Resource<TerrainFile> file );
+   void setFile(const Resource<TerrainFile>& file);
 
    bool save(const char* filename);
 
diff --git a/Engine/source/util/triBoxCheck.h b/Engine/source/util/triBoxCheck.h
index 8d41bb451..ede5d995d 100644
--- a/Engine/source/util/triBoxCheck.h
+++ b/Engine/source/util/triBoxCheck.h
@@ -38,7 +38,7 @@ bool triBoxOverlap(const Point3F &boxcenter, const Point3F &boxhalfsize, const P
 
 /// Massage stuff into right format for triBoxOverlap test. This is really
 /// just a helper function - use the other version if you want to be fast!
-inline bool triBoxOverlap(Box3F box, Point3F a, Point3F b, Point3F c)
+inline bool triBoxOverlap(Box3F box, const Point3F& a, const Point3F& b, const Point3F& c)
 {
    Point3F halfSize(box.len_x() / 2.f, box.len_y() / 2.f, box.len_z() / 2.f);
 
diff --git a/Engine/source/util/triRayCheck.cpp b/Engine/source/util/triRayCheck.cpp
index 084eda21b..e2ef3af41 100644
--- a/Engine/source/util/triRayCheck.cpp
+++ b/Engine/source/util/triRayCheck.cpp
@@ -125,8 +125,8 @@ bool intersect_triangle(Point3F orig, Point3F dir,
 }
 
 //*** Taken from TSE, and based on the above
-bool castRayTriangle(Point3F orig, Point3F dir,
-   Point3F vert0, Point3F vert1, Point3F vert2,
+bool castRayTriangle(const Point3F& orig, const Point3F& dir,
+   const Point3F& vert0, const Point3F& vert1, const Point3F& vert2,
    F32 &t, Point2F &bary)
 {
    Point3F tvec, qvec;
diff --git a/Engine/source/util/triRayCheck.h b/Engine/source/util/triRayCheck.h
index 20f6cb49e..adf746053 100644
--- a/Engine/source/util/triRayCheck.h
+++ b/Engine/source/util/triRayCheck.h
@@ -38,7 +38,7 @@ bool intersect_triangle(Point3F orig, Point3F dir,
                    F32& t, F32& u, F32& v);
 
 //*** Taken from TSE, but based on the above
-bool castRayTriangle(Point3F orig, Point3F dir, Point3F vert0, Point3F vert1, Point3F vert2, F32 &t, Point2F &bary);
+bool castRayTriangle(const Point3F& orig, const Point3F& dir, const Point3F& vert0, const Point3F& vert1, const Point3F& vert2, F32 &t, Point2F &bary);
 bool castRayTriangle(const Point3D &orig, const Point3D &dir, const Point3D &vert0, const Point3D &vert1, const Point3D &vert2);
 
 #endif // _TRIRAYCHECK_H_