diff --git a/source/gfx/prim.h b/source/gfx/prim.h
index ade4145dd..74a0d9f13 100644
--- a/source/gfx/prim.h
+++ b/source/gfx/prim.h
@@ -248,52 +248,52 @@ typedef	u32	sOT;
 
 // Extra prims :o)
 #define GetPrimTF3() 		GetPrim(TPOLY_F3);\
-				   			setTPolyF3(CurrPrim-sizeof(TPOLY_F3))
+				   			setTPolyF3((TPOLY_F3*)CurrPrim-sizeof(TPOLY_F3))
 
 #define GetPrimTF4() 		GetPrim(TPOLY_F4);\
-				   			setTPolyF4(CurrPrim-sizeof(TPOLY_F4))
+				   			setTPolyF4((TPOLY_F4*)CurrPrim-sizeof(TPOLY_F4))
 
 #define GetPrimTG3()		GetPrim(TPOLY_G3);\
-				   			setTPolyG3(CurrPrim-sizeof(TPOLY_G3))
+				   			setTPolyG3((TPOLY_G3*)CurrPrim-sizeof(TPOLY_G3))
 
 #define GetPrimTG4() 		GetPrim(TPOLY_G4);\
-				   			setTPolyG4(CurrPrim-sizeof(TPOLY_G4))
+				   			setTPolyG4((TPOLY_G4*)CurrPrim-sizeof(TPOLY_G4))
 
 #define GetPrimTLF2() 		GetPrim(TLINE_F2);  \
-							setTLineF2(CurrPrim-sizeof(TLINE_F2))
+							setTLineF2((TLINE_F2*)CurrPrim-sizeof(TLINE_F2))
 
 #define GetPrimTLF3() 		GetPrim(TLINE_F3);\
-							setTLineF3(CurrPrim-sizeof(TLINE_F3))
+							setTLineF3((TLINE_F3*)CurrPrim-sizeof(TLINE_F3))
 
 #define GetPrimTLF4() 		GetPrim(TLINE_F4);\
 							setTLineF4((TLINE_F4*)CurrPrim-1)
 
 #define GetPrimTLG2() 		GetPrim(TLINE_G2);\
-							setTLineG2(CurrPrim-sizeof(TLINE_G2))
+							setTLineG2((TLINE_G2*)CurrPrim-sizeof(TLINE_G2))
 
 #define GetPrimTLG3() 		GetPrim(TLINE_G3);\
-							setTLineG3(CurrPrim-sizeof(TLINE_G3))
+							setTLineG3((TLINE_G3*)CurrPrim-sizeof(TLINE_G3))
 
 #define GetPrimTLG4() 		GetPrim(TLINE_G4);\
-							setTLineG4(CurrPrim-sizeof(TLINE_G4))
+							setTLineG4((TLINE_G4*)CurrPrim-sizeof(TLINE_G4))
 
 #define GetPrimTSPRT8() 	GetPrim(TSPRT8);\
-							setTSprt8(CurrPrim-sizeof(TSPRT8))
+							setTSprt8((TSPRT8*)CurrPrim-sizeof(TSPRT8))
 
 #define GetPrimTSPRT16() 	GetPrim(TSPRT16);\
-							setTSprt16(CurrPrim-sizeof(TSPRT16))
+							setTSprt16((TSPRT16*)CurrPrim-sizeof(TSPRT16))
 
 #define GetPrimTSPRT() 		GetPrim(TSPRT);\
-							setTSprt(CurrPrim-sizeof(TSPRT))
+							setTSprt((TSPRT*)CurrPrim-sizeof(TSPRT))
 
 #define GetPrimTTILE8() 	GetPrim(TTILE8);\
-							setTile(CurrPrim-sizeof(TTILE8))
+							setTile((TTILE8*)CurrPrim-sizeof(TTILE8))
 
 #define GetPrimTTILE16() 	GetPrim(TTILE16);\
-							setTile(CurrPrim-sizeof(TTILE16))
+							setTile((TTILE16*)CurrPrim-sizeof(TTILE16))
 
 #define GetPrimTTILE() 		GetPrim(TTILE);\
-							setTile(CurrPrim-sizeof(TTILE))
+							setTile((TTILE*)CurrPrim-sizeof(TTILE))
 
 
 /********************************************************************************************************/
diff --git a/source/thing/thing.cpp b/source/thing/thing.cpp
index 6e0161423..c34400aa4 100644
--- a/source/thing/thing.cpp
+++ b/source/thing/thing.cpp
@@ -1092,6 +1092,16 @@ DVECTOR	const	&CamPos=CLevel::getCameraPos();
 #endif
 
 }
+
+/****************************************************************************************/
+void	CThing::calcRenderPos(DVECTOR const &Pos,DVECTOR &renderPos)
+{
+DVECTOR	const	&CamPos=CLevel::getCameraPos();
+
+		renderPos.vx = Pos.vx - CamPos.vx;
+		renderPos.vy = Pos.vy - CamPos.vy;
+}
+
 /****************************************************************************************/
 #ifdef	SHOW_BBOX
 #include "gfx\prim.h"
diff --git a/source/thing/thing.h b/source/thing/thing.h
index 192b21d72..9cbe91b3f 100644
--- a/source/thing/thing.h
+++ b/source/thing/thing.h
@@ -51,50 +51,50 @@ class	CThing;
 class	CThingManager
 {
 public:
-	static void		init();
-	static void		shutdown();
-	static void		killAllThingsForRespawn();
+static	void		init();
+static	void		shutdown();
+static	void		killAllThingsForRespawn();
 
-	static void		initAllThings();
-	static void		thinkAllThings(int _frames);
-	static void		renderAllThings();
-	static void		processEventAllThings(GAME_EVENT _event,CThing *_sourceThing);
+static	void		initAllThings();
+static	void		thinkAllThings(int _frames);
+static	void		renderAllThings();
+static	void		processEventAllThings(GAME_EVENT _event,CThing *_sourceThing);
 
-	static CThing*	checkCollisionAreaAgainstThings(CRECT *_area,int _type,int _continue);
-	static void		initCollision();
-	static void		matchWheelsAndWeights();
-	static void		matchPressureSwitches();
-	static void		matchGaryTriggers();
+static	CThing		*checkCollisionAreaAgainstThings(CRECT *_area,int _type,int _continue);
+static	void		initCollision();
+static	void		matchWheelsAndWeights();
+static	void		matchPressureSwitches();
+static	void		matchGaryTriggers();
 
-	static sBBox	&getRenderBBox()			{return(m_RenderBBox);}
-	static sBBox	&getThinkBBox()				{return(m_ThinkBBox);}
+static	sBBox		&getRenderBBox()			{return(m_RenderBBox);}
+static	sBBox		&getThinkBBox()				{return(m_ThinkBBox);}
 
 protected:
-	static void		initList(CThing **List);
-	static void		addToThingList(CThing *_this);
-	static void		removeFromThingList(CThing *_this);
+static	void		initList(CThing **List);
+static	void		addToThingList(CThing *_this);
+static	void		removeFromThingList(CThing *_this);
 
-	static void		addToCollisionList(CThing *_this);
+static void			addToCollisionList(CThing *_this);
 
-friend class CThing;
+friend	class CThing;
 
 private:
-	static CThing			*s_thingLists[];
-	static int				s_initialised;
+static	CThing		*s_thingLists[];
+static	int			s_initialised;
 
-	static CThing			*s_CollisionLists[];
-	static sBBox			m_RenderBBox;
-	static sBBox			m_ThinkBBox;
+static	CThing		*s_CollisionLists[];
+static	sBBox		m_RenderBBox;
+static	sBBox		m_ThinkBBox;
 public:
 // FreeList Stuff
-	static void		initFreeList();
-	static void		resetFreeList();
-	static void		shutdownFreeList();
-	static	CThing	*GetThing(int Type,int SubType);
-	static	void	DeleteThing(CThing *Thing);
+static	void		initFreeList();
+static	void		resetFreeList();
+static	void		shutdownFreeList();
+static	CThing		*GetThing(int Type,int SubType);
+static	void		DeleteThing(CThing *Thing);
 
 private:
-	static CThing			**s_FreeList[];
+static	CThing		**s_FreeList[];
 };
 
 
@@ -150,6 +150,7 @@ virtual	void	render();
 		void	setToShutdown(bool f=true)								{m_isShuttingDown = f;}
 		u8		isSetToShutdown()										{return( m_isShuttingDown);}
 virtual int		dontKillDuringLevelRespawn()							{return false;}
+		void	calcRenderPos(DVECTOR const &Pos,DVECTOR &renderPos);
 
 // Linkage
 		void			addChild(CThing *Child);