diff --git a/src/actor.h b/src/actor.h
index 3cc6cf9ca6..1b2c93d56f 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -865,13 +865,13 @@ public:
 	// more precise, but slower version, being used in a few places
 	fixed_t Distance2D(AActor *other, bool absolute = false)
 	{
-		return xs_RoundToInt(FVector2(X() - other->X(), Y() - other->Y()).Length());
+		return xs_RoundToInt(TVector2<double>(X() - other->X(), Y() - other->Y()).Length());
 	}
 
 	// a full 3D version of the above
 	fixed_t Distance3D(AActor *other, bool absolute = false)
 	{
-		return xs_RoundToInt(FVector3(X() - other->X(), Y() - other->Y(), Z() - other->Z()).Length());
+		return xs_RoundToInt(TVector3<double>(X() - other->X(), Y() - other->Y(), Z() - other->Z()).Length());
 	}
 
 	angle_t AngleTo(AActor *other, bool absolute = false) const
diff --git a/src/am_map.cpp b/src/am_map.cpp
index 3768af858d..df464e59dc 100644
--- a/src/am_map.cpp
+++ b/src/am_map.cpp
@@ -2512,8 +2512,8 @@ void AM_rotate(fixed_t *xp, fixed_t *yp, angle_t a)
 		cosrot = cos(rot);
 	}
 
-	double x = FIXED2FLOAT(*xp);
-	double y = FIXED2FLOAT(*yp);
+	double x = FIXED2DBL(*xp);
+	double y = FIXED2DBL(*yp);
 	double tmpx = (x * cosrot) - (y * sinrot);
 	y = (x * sinrot) + (y * cosrot);
 	x = tmpx;
diff --git a/src/c_cmds.cpp b/src/c_cmds.cpp
index ed028ab934..1d16af31f6 100644
--- a/src/c_cmds.cpp
+++ b/src/c_cmds.cpp
@@ -1084,7 +1084,7 @@ CCMD(currentpos)
 	if(mo)
 	{
 		Printf("Current player position: (%1.3f,%1.3f,%1.3f), angle: %1.3f, floorheight: %1.3f, sector:%d, lightlevel: %d\n",
-			FIXED2FLOAT(mo->X()), FIXED2FLOAT(mo->Y()), FIXED2FLOAT(mo->Z()), mo->angle/float(ANGLE_1), FIXED2FLOAT(mo->floorz), mo->Sector->sectornum, mo->Sector->lightlevel);
+			FIXED2DBL(mo->X()), FIXED2DBL(mo->Y()), FIXED2DBL(mo->Z()), ANGLE2DBL(mo->angle), FIXED2DBL(mo->floorz), mo->Sector->sectornum, mo->Sector->lightlevel);
 	}
 	else
 	{
diff --git a/src/d_main.cpp b/src/d_main.cpp
index 23c837dfab..d2120f88e1 100644
--- a/src/d_main.cpp
+++ b/src/d_main.cpp
@@ -2481,8 +2481,9 @@ void D_DoomMain (void)
 		FinishDehPatch();
 
 		InitActorNumsFromMapinfo();
-		PClassActor::StaticSetActorNums ();
 		InitSpawnablesFromMapinfo();
+		PClassActor::StaticSetActorNums();
+
 		//Added by MC:
 		bglobal.getspawned.Clear();
 		argcount = Args->CheckParmList("-bots", &args);
diff --git a/src/dsectoreffect.cpp b/src/dsectoreffect.cpp
index 6732a19dc8..7bc9fc400e 100644
--- a/src/dsectoreffect.cpp
+++ b/src/dsectoreffect.cpp
@@ -95,11 +95,11 @@ void DMover::Serialize (FArchive &arc)
 	arc << interpolation;
 }
 
-void DMover::StopInterpolation()
+void DMover::StopInterpolation(bool force)
 {
 	if (interpolation != NULL)
 	{
-		interpolation->DelRef();
+		interpolation->DelRef(force);
 		interpolation = NULL;
 	}
 }
diff --git a/src/dsectoreffect.h b/src/dsectoreffect.h
index 95e1178aa3..3788c6d88f 100644
--- a/src/dsectoreffect.h
+++ b/src/dsectoreffect.h
@@ -36,7 +36,7 @@ protected:
 	DMover ();
 	void Serialize (FArchive &arc);
 	void Destroy();
-	void StopInterpolation();
+	void StopInterpolation(bool force = false);
 	inline EResult MoveFloor (fixed_t speed, fixed_t dest, int crush, int direction, bool hexencrush)
 	{
 		return MovePlane (speed, dest, crush, 0, direction, hexencrush);
diff --git a/src/fragglescript/t_func.cpp b/src/fragglescript/t_func.cpp
index e5803fb3ea..8be7f798d6 100644
--- a/src/fragglescript/t_func.cpp
+++ b/src/fragglescript/t_func.cpp
@@ -1571,7 +1571,7 @@ public:
 		bool res = DMover::crushed != MoveFloor(speed, dest, crush, direction, false);
 		Destroy();
 		m_Sector->floordata=NULL;
-		StopInterpolation();
+		StopInterpolation(true);
 		m_Sector=NULL;
 		return res;
 	}
@@ -1656,6 +1656,14 @@ public:
 		m_Speed=movespeed;
 		m_Direction = _m_Direction;
 		m_FloorDestDist = moveheight;
+
+		// Do not interpolate instant movement floors.
+		fixed_t movedist = abs(-sec->floorplane.d - moveheight);
+		if (m_Speed >= movedist)
+		{
+			StopInterpolation(true);
+		}
+
 		StartFloorSound();
 	}
 };
@@ -1713,7 +1721,7 @@ public:
 		bool res = DMover::crushed != MoveCeiling(speed, dest, crush, direction, false);
 		Destroy();
 		m_Sector->ceilingdata=NULL;
-		StopInterpolation ();
+		StopInterpolation (true);
 		m_Sector=NULL;
 		return res;
 	}
@@ -1806,7 +1814,7 @@ public:
 		fixed_t movedist = abs(sec->ceilingplane.d - m_BottomHeight);
 		if (m_Speed >= movedist)
 		{
-			StopInterpolation ();
+			StopInterpolation (true);
 			m_Silent=2;
 		}
 		PlayCeilingSound();
@@ -3817,19 +3825,12 @@ void FParser::SF_ObjType()
 //
 //==========================================================================
 
-inline fixed_t double2fixed(double t)
-{
-	return (fixed_t)(t*65536.0);
-}
-
-
-
 void FParser::SF_Sin()
 {
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(sin(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(sin(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3839,7 +3840,7 @@ void FParser::SF_ASin()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(asin(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(asin(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3849,7 +3850,7 @@ void FParser::SF_Cos()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(cos(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(cos(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3859,7 +3860,7 @@ void FParser::SF_ACos()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(acos(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(acos(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3869,7 +3870,7 @@ void FParser::SF_Tan()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(tan(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(tan(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3879,7 +3880,7 @@ void FParser::SF_ATan()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(atan(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(atan(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3889,7 +3890,7 @@ void FParser::SF_Exp()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(exp(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(exp(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3898,7 +3899,7 @@ void FParser::SF_Log()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(log(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(log(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3908,7 +3909,7 @@ void FParser::SF_Sqrt()
 	if (CheckArgs(1))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(sqrt(floatvalue(t_argv[0])));
+		t_return.value.f = FLOAT2FIXED(sqrt(floatvalue(t_argv[0])));
 	}
 }
 
@@ -3928,7 +3929,7 @@ void FParser::SF_Pow()
 	if (CheckArgs(2))
 	{
 		t_return.type = svt_fixed;
-		t_return.value.f = double2fixed(pow(floatvalue(t_argv[0]), floatvalue(t_argv[1])));
+		t_return.value.f = FLOAT2FIXED(pow(floatvalue(t_argv[0]), floatvalue(t_argv[1])));
 	}
 }
 
diff --git a/src/g_shared/a_movingcamera.cpp b/src/g_shared/a_movingcamera.cpp
index c01dea4973..87a6e71ece 100644
--- a/src/g_shared/a_movingcamera.cpp
+++ b/src/g_shared/a_movingcamera.cpp
@@ -165,8 +165,8 @@ public:
 	void Activate (AActor *activator);
 	void Deactivate (AActor *activator);
 protected:
-	float Splerp (float p1, float p2, float p3, float p4);
-	float Lerp (float p1, float p2);
+	double Splerp (double p1, double p2, double p3, double p4);
+	double Lerp (double p1, double p2);
 	virtual bool Interpolate ();
 	virtual void NewNode ();
 
@@ -191,10 +191,10 @@ void APathFollower::Serialize (FArchive &arc)
 
 // Interpolate between p2 and p3 along a Catmull-Rom spline
 // http://research.microsoft.com/~hollasch/cgindex/curves/catmull-rom.html
-float APathFollower::Splerp (float p1, float p2, float p3, float p4)
+double APathFollower::Splerp (double p1, double p2, double p3, double p4)
 {
-	float t = Time;
-	float res = 2*p2;
+	double t = Time;
+	double res = 2*p2;
 	res += (p3 - p1) * Time;
 	t *= Time;
 	res += (2*p1 - 5*p2 + 4*p3 - p4) * t;
@@ -204,7 +204,7 @@ float APathFollower::Splerp (float p1, float p2, float p3, float p4)
 }
 
 // Linearly interpolate between p1 and p2
-float APathFollower::Lerp (float p1, float p2)
+double APathFollower::Lerp (double p1, double p2)
 {
 	return p1 + Time * (p2 - p1);
 }
@@ -325,7 +325,7 @@ void APathFollower::Tick ()
 
 	if (Interpolate ())
 	{
-		Time += 8.f / ((float)CurrNode->args[1] * (float)TICRATE);
+		Time += float(8.f / ((double)CurrNode->args[1] * (double)TICRATE));
 		if (Time > 1.f)
 		{
 			Time -= 1.f;
@@ -371,20 +371,20 @@ bool APathFollower::Interpolate ()
 	fixed_t x, y, z;
 	if (args[2] & 1)
 	{	// linear
-		x = FLOAT2FIXED(Lerp (FIXED2FLOAT(CurrNode->X()), FIXED2FLOAT(CurrNode->Next->X())));
-		y = FLOAT2FIXED(Lerp (FIXED2FLOAT(CurrNode->Y()), FIXED2FLOAT(CurrNode->Next->Y())));
-		z = FLOAT2FIXED(Lerp (FIXED2FLOAT(CurrNode->Z()), FIXED2FLOAT(CurrNode->Next->Z())));
+		x = FLOAT2FIXED(Lerp (FIXED2DBL(CurrNode->X()), FIXED2DBL(CurrNode->Next->X())));
+		y = FLOAT2FIXED(Lerp (FIXED2DBL(CurrNode->Y()), FIXED2DBL(CurrNode->Next->Y())));
+		z = FLOAT2FIXED(Lerp (FIXED2DBL(CurrNode->Z()), FIXED2DBL(CurrNode->Next->Z())));
 	}
 	else
 	{	// spline
 		if (CurrNode->Next->Next==NULL) return false;
 
-		x = FLOAT2FIXED(Splerp (FIXED2FLOAT(PrevNode->X()), FIXED2FLOAT(CurrNode->X()),
-								FIXED2FLOAT(CurrNode->Next->X()), FIXED2FLOAT(CurrNode->Next->Next->X())));
-		y = FLOAT2FIXED(Splerp (FIXED2FLOAT(PrevNode->Y()), FIXED2FLOAT(CurrNode->Y()),
-								FIXED2FLOAT(CurrNode->Next->Y()), FIXED2FLOAT(CurrNode->Next->Next->Y())));
-		z = FLOAT2FIXED(Splerp (FIXED2FLOAT(PrevNode->Z()), FIXED2FLOAT(CurrNode->Z()),
-								FIXED2FLOAT(CurrNode->Next->Z()), FIXED2FLOAT(CurrNode->Next->Next->Z())));
+		x = FLOAT2FIXED(Splerp (FIXED2DBL(PrevNode->X()), FIXED2DBL(CurrNode->X()),
+								FIXED2DBL(CurrNode->Next->X()), FIXED2DBL(CurrNode->Next->Next->X())));
+		y = FLOAT2FIXED(Splerp (FIXED2DBL(PrevNode->Y()), FIXED2DBL(CurrNode->Y()),
+								FIXED2DBL(CurrNode->Next->Y()), FIXED2DBL(CurrNode->Next->Next->Y())));
+		z = FLOAT2FIXED(Splerp (FIXED2DBL(PrevNode->Z()), FIXED2DBL(CurrNode->Z()),
+								FIXED2DBL(CurrNode->Next->Z()), FIXED2DBL(CurrNode->Next->Next->Z())));
 	}
 	SetXYZ(x, y, z);
 	LinkToWorld ();
@@ -442,11 +442,11 @@ bool APathFollower::Interpolate ()
 		{
 			if (args[2] & 2)
 			{ // interpolate angle
-				float angle1 = (float)CurrNode->angle;
-				float angle2 = (float)CurrNode->Next->angle;
+				double angle1 = (double)CurrNode->angle;
+				double angle2 = (double)CurrNode->Next->angle;
 				if (angle2 - angle1 <= -2147483648.f)
 				{
-					float lerped = Lerp (angle1, angle2 + 4294967296.f);
+					double lerped = Lerp (angle1, angle2 + 4294967296.f);
 					if (lerped >= 4294967296.f)
 					{
 						angle = xs_CRoundToUInt(lerped - 4294967296.f);
@@ -458,7 +458,7 @@ bool APathFollower::Interpolate ()
 				}
 				else if (angle2 - angle1 >= 2147483648.f)
 				{
-					float lerped = Lerp (angle1, angle2 - 4294967296.f);
+					double lerped = Lerp (angle1, angle2 - 4294967296.f);
 					if (lerped < 0.f)
 					{
 						angle = xs_CRoundToUInt(lerped + 4294967296.f);
@@ -477,15 +477,15 @@ bool APathFollower::Interpolate ()
 			{ // linear
 				if (args[2] & 4)
 				{ // interpolate pitch
-					pitch = FLOAT2FIXED(Lerp (FIXED2FLOAT(CurrNode->pitch), FIXED2FLOAT(CurrNode->Next->pitch)));
+					pitch = FLOAT2FIXED(Lerp (FIXED2DBL(CurrNode->pitch), FIXED2DBL(CurrNode->Next->pitch)));
 				}
 			}
 			else
 			{ // spline
 				if (args[2] & 4)
 				{ // interpolate pitch
-					pitch = FLOAT2FIXED(Splerp (FIXED2FLOAT(PrevNode->pitch), FIXED2FLOAT(CurrNode->pitch),
-						FIXED2FLOAT(CurrNode->Next->pitch), FIXED2FLOAT(CurrNode->Next->Next->pitch)));
+					pitch = FLOAT2FIXED(Splerp (FIXED2DBL(PrevNode->pitch), FIXED2DBL(CurrNode->pitch),
+						FIXED2DBL(CurrNode->Next->pitch), FIXED2DBL(CurrNode->Next->Next->pitch)));
 				}
 			}
 		}
diff --git a/src/g_shared/sbarinfo_commands.cpp b/src/g_shared/sbarinfo_commands.cpp
index ed2a8c29c8..5e2fa816f6 100644
--- a/src/g_shared/sbarinfo_commands.cpp
+++ b/src/g_shared/sbarinfo_commands.cpp
@@ -310,8 +310,8 @@ class CommandDrawImage : public SBarInfoCommandFlowControl
 			
 			if (applyscale)
 			{
-				spawnScaleX = FIXED2FLOAT(item->scaleX);
-				spawnScaleY = FIXED2FLOAT(item->scaleY);
+				spawnScaleX = FIXED2DBL(item->scaleX);
+				spawnScaleY = FIXED2DBL(item->scaleY);
 			}
 			
 			texture = TexMan[icon];
diff --git a/src/p_acs.cpp b/src/p_acs.cpp
index 0ddbdf0c20..070111d7b3 100644
--- a/src/p_acs.cpp
+++ b/src/p_acs.cpp
@@ -7782,8 +7782,12 @@ scriptwait:
 						break;
 
 					case PRINTNAME_LEVEL:
-						work += level.MapName;
-						break;
+					{
+						FString uppername = level.MapName;
+						uppername.ToUpper();
+						work += uppername;
+						break; 
+					}
 
 					case PRINTNAME_SKILL:
 						work += G_SkillName();
diff --git a/src/p_buildmap.cpp b/src/p_buildmap.cpp
index 295dff8314..6705addd6b 100644
--- a/src/p_buildmap.cpp
+++ b/src/p_buildmap.cpp
@@ -804,7 +804,7 @@ static void CreateStartSpot (fixed_t *pos, FMapThing *start)
 
 static void CalcPlane (SlopeWork &slope, secplane_t &plane)
 {
-	FVector3 pt[3];
+	TVector3<double> pt[3];
 	long j;
 
 	slope.x[0] = slope.wal->x;  slope.y[0] = slope.wal->y;
@@ -823,8 +823,8 @@ static void CalcPlane (SlopeWork &slope, secplane_t &plane)
 		-slope.dy, slope.x[2]-slope.wal->x);
 	slope.z[2] += Scale (slope.heinum, j, slope.i);
 
-	pt[0] = FVector3(slope.dx, -slope.dy, 0);
-	pt[1] = FVector3(slope.x[2] - slope.x[0], slope.y[0] - slope.y[2], (slope.z[2] - slope.z[0]) / 16);
+	pt[0] = TVector3<double>(slope.dx, -slope.dy, 0);
+	pt[1] = TVector3<double>(slope.x[2] - slope.x[0], slope.y[0] - slope.y[2], (slope.z[2] - slope.z[0]) / 16);
 	pt[2] = (pt[0] ^ pt[1]).Unit();
 
 	if ((pt[2][2] < 0 && plane.c > 0) || (pt[2][2] > 0 && plane.c < 0))
@@ -832,10 +832,10 @@ static void CalcPlane (SlopeWork &slope, secplane_t &plane)
 		pt[2] = -pt[2];
 	}
 
-	plane.a = fixed_t(pt[2][0]*65536.f);
-	plane.b = fixed_t(pt[2][1]*65536.f);
-	plane.c = fixed_t(pt[2][2]*65536.f);
-	plane.ic = fixed_t(65536.f/pt[2][2]);
+	plane.a = FLOAT2FIXED(pt[2][0]);
+	plane.b = FLOAT2FIXED(pt[2][1]);
+	plane.c = FLOAT2FIXED(pt[2][2]);
+	plane.ic = DivScale32(1, plane.c);
 	plane.d = -TMulScale8
 		(plane.a, slope.x[0]<<4, plane.b, (-slope.y[0])<<4, plane.c, slope.z[0]);
 }
diff --git a/src/p_ceiling.cpp b/src/p_ceiling.cpp
index 3203cf7779..24ab121c41 100644
--- a/src/p_ceiling.cpp
+++ b/src/p_ceiling.cpp
@@ -412,7 +412,7 @@ DCeiling *DCeiling::Create(sector_t *sec, DCeiling::ECeiling type, line_t *line,
 	}
 	if (ceiling->m_Speed >= movedist)
 	{
-		ceiling->StopInterpolation();
+		ceiling->StopInterpolation(true);
 	}
 
 	// set texture/type change properties
diff --git a/src/p_enemy.cpp b/src/p_enemy.cpp
index 42bb6c7acd..ad286fdd49 100644
--- a/src/p_enemy.cpp
+++ b/src/p_enemy.cpp
@@ -1792,7 +1792,7 @@ DEFINE_ACTION_FUNCTION(AActor, A_Look)
 			}
 			else
 			{
-				CALL_ACTION(A_Wander, self);
+				A_Wander(self);
 			}
 		}
 		else
@@ -1952,7 +1952,7 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_LookEx)
                         }
                         else
                         {
-                            CALL_ACTION(A_Wander, self);
+                            A_Wander(self);
                         }
                     }
                 }
@@ -2051,50 +2051,74 @@ DEFINE_ACTION_FUNCTION(AActor, A_ClearLastHeard)
 // A_Wander
 //
 //==========================================================================
-DEFINE_ACTION_FUNCTION(AActor, A_Wander)
+enum ChaseFlags
+{
+	CHF_FASTCHASE = 1,
+	CHF_NOPLAYACTIVE = 2,
+	CHF_NIGHTMAREFAST = 4,
+	CHF_RESURRECT = 8,
+	CHF_DONTMOVE = 16,
+	CHF_NORANDOMTURN = 32,
+	CHF_NODIRECTIONTURN = 64,
+	CHF_NOPOSTATTACKTURN = 128,
+	CHF_STOPIFBLOCKED = 256,
+};
+
+DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_Wander)
 {
 	PARAM_ACTION_PROLOGUE;
+	PARAM_INT_OPT(flags) { flags = 0; }	
+	A_Wander(self, flags);
+	return 0;
+}
 
+// [MC] I had to move this out from within A_Wander in order to allow flags to 
+// pass into it. That meant replacing the CALL_ACTION(A_Wander) functions with
+// just straight up defining A_Wander in order to compile. Looking around though,
+// actors from the games themselves just do a straight A_Chase call itself so
+// I saw no harm in it.
+
+void A_Wander(AActor *self, int flags)
+{
 	// [RH] Strife probably clears this flag somewhere, but I couldn't find where.
 	// This seems as good a place as any.
 	self->flags4 &= ~MF4_INCOMBAT;
 
 	if (self->flags5 & MF5_INCONVERSATION)
-		return 0;
+		return;
 
 	if (self->flags4 & MF4_STANDSTILL)
-		return 0;
+		return;
 
 	if (self->reactiontime != 0)
 	{
 		self->reactiontime--;
-		return 0;
+		return;
 	}
 
 	// turn towards movement direction if not there yet
-	if (self->movedir < DI_NODIR)
+	if (!(flags & CHF_NODIRECTIONTURN) && (self->movedir < DI_NODIR))
 	{
-		self->angle &= (angle_t)(7<<29);
+		self->angle &= (angle_t)(7 << 29);
 		int delta = self->angle - (self->movedir << 29);
 		if (delta > 0)
 		{
-			self->angle -= ANG90/2;
+			self->angle -= ANG90 / 2;
 		}
 		else if (delta < 0)
 		{
-			self->angle += ANG90/2;
+			self->angle += ANG90 / 2;
 		}
 	}
 
-	if (--self->movecount < 0 || !P_Move (self))
+	if ((--self->movecount < 0 && !(flags & CHF_NORANDOMTURN)) || (!P_Move(self) && !(flags & CHF_STOPIFBLOCKED)))
 	{
-		P_RandomChaseDir (self);
+		P_RandomChaseDir(self);
 		self->movecount += 5;
 	}
-	return 0;
+	return;
 }
 
-
 //==========================================================================
 //
 // A_Look2
@@ -2165,8 +2189,8 @@ nosee:
 //
 //=============================================================================
 #define CLASS_BOSS_STRAFE_RANGE	64*10*FRACUNIT
-
-void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *meleestate, FState *missilestate, bool playactive, bool nightmarefast, bool dontmove)
+
+void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *meleestate, FState *missilestate, bool playactive, bool nightmarefast, bool dontmove, int flags)
 {
 	int delta;
 
@@ -2228,7 +2252,7 @@ void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *mele
 	{
 		A_FaceTarget(actor);
 	}
-	else if (actor->movedir < 8)
+	else if (!(flags & CHF_NODIRECTIONTURN) && actor->movedir < 8)
 	{
 		actor->angle &= (angle_t)(7<<29);
 		delta = actor->angle - (actor->movedir << 29);
@@ -2300,7 +2324,7 @@ void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *mele
 				//CALL_ACTION(A_Look, actor);
 				if (actor->target == NULL)
 				{
-					if (!dontmove) CALL_ACTION(A_Wander, actor);
+					if (!dontmove) A_Wander(actor);
 					actor->flags &= ~MF_INCHASE;
 					return;
 				}
@@ -2318,10 +2342,15 @@ void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *mele
 	if (actor->flags & MF_JUSTATTACKED)
 	{
 		actor->flags &= ~MF_JUSTATTACKED;
-		if (!actor->isFast() && !dontmove)
+		if (!actor->isFast() && !dontmove && !(flags & CHF_NOPOSTATTACKTURN) && !(flags & CHF_STOPIFBLOCKED))
 		{
 			P_NewChaseDir (actor);
 		}
+		//Because P_TryWalk would never be reached if the actor is stopped by a blocking object,
+		//need to make sure the movecount is reset, otherwise they will just keep attacking
+		//over and over again.
+		if (flags & CHF_STOPIFBLOCKED)
+			actor->movecount = pr_trywalk() & 15;
 		actor->flags &= ~MF_INCHASE;
 		return;
 	}
@@ -2478,7 +2507,7 @@ void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *mele
 
 	if (actor->strafecount)
 		actor->strafecount--;
-
+	
 	// class bosses don't do this when strafing
 	if ((!fastchase || !actor->FastChaseStrafeCount) && !dontmove)
 	{
@@ -2488,16 +2517,15 @@ void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *mele
 		FTextureID oldFloor = actor->floorpic;
 
 		// chase towards player
-		if (--actor->movecount < 0 || !P_Move (actor))
+		if ((--actor->movecount < 0 && !(flags & CHF_NORANDOMTURN)) || (!P_Move(actor) && !(flags & CHF_STOPIFBLOCKED)))
 		{
-			P_NewChaseDir (actor);
+			P_NewChaseDir(actor);
 		}
-		
 		// if the move was illegal, reset it 
 		// (copied from A_SerpentChase - it applies to everything with CANTLEAVEFLOORPIC!)
 		if (actor->flags2&MF2_CANTLEAVEFLOORPIC && actor->floorpic != oldFloor )
 		{
-			if (P_TryMove (actor, oldX, oldY, false))
+			if (P_TryMove(actor, oldX, oldY, false))
 			{
 				if (nomonsterinterpolation)
 				{
@@ -2505,7 +2533,8 @@ void A_DoChase (VMFrameStack *stack, AActor *actor, bool fastchase, FState *mele
 					actor->PrevY = oldY;
 				}
 			}
-			P_NewChaseDir (actor);
+			if (!(flags & CHF_STOPIFBLOCKED))
+				P_NewChaseDir(actor);
 		}
 	}
 	else if (dontmove && actor->movecount > 0) actor->movecount--;
@@ -2666,15 +2695,6 @@ static bool P_CheckForResurrection(AActor *self, bool usevilestates)
 //
 //==========================================================================
 
-enum ChaseFlags
-{
-	CHF_FASTCHASE = 1,
-	CHF_NOPLAYACTIVE = 2,
-	CHF_NIGHTMAREFAST = 4,
-	CHF_RESURRECT = 8,
-	CHF_DONTMOVE = 16,
-};
-
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_Chase)
 {
 	PARAM_ACTION_PROLOGUE;
@@ -2686,22 +2706,22 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_Chase)
 	{
 		if ((flags & CHF_RESURRECT) && P_CheckForResurrection(self, false))
 			return 0;
-		
+		
 		A_DoChase(stack, self, !!(flags&CHF_FASTCHASE), melee, missile, !(flags&CHF_NOPLAYACTIVE), 
-					!!(flags&CHF_NIGHTMAREFAST), !!(flags&CHF_DONTMOVE));
+					!!(flags&CHF_NIGHTMAREFAST), !!(flags&CHF_DONTMOVE), flags);
 	}
 	else // this is the old default A_Chase
 	{
-		A_DoChase(stack, self, false, self->MeleeState, self->MissileState, true, gameinfo.nightmarefast, false);
+		A_DoChase(stack, self, false, self->MeleeState, self->MissileState, true, gameinfo.nightmarefast, false, flags);
 	}
 	return 0;
 }
 
 DEFINE_ACTION_FUNCTION(AActor, A_FastChase)
-{
+{
 	PARAM_ACTION_PROLOGUE;
-	A_DoChase(stack, self, true, self->MeleeState, self->MissileState, true, true, false);
-	return 0;
+	A_DoChase(stack, self, true, self->MeleeState, self->MissileState, true, true, false, 0);
+	return 0;
 }
 
 DEFINE_ACTION_FUNCTION(AActor, A_VileChase)
@@ -2709,9 +2729,9 @@ DEFINE_ACTION_FUNCTION(AActor, A_VileChase)
 	PARAM_ACTION_PROLOGUE;
 	if (!P_CheckForResurrection(self, true))
 	{
-		A_DoChase(stack, self, false, self->MeleeState, self->MissileState, true, gameinfo.nightmarefast, false);
+		A_DoChase(stack, self, false, self->MeleeState, self->MissileState, true, gameinfo.nightmarefast, false, 0);
 	}
-	return 0;
+	return 0;
 }
 
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_ExtChase)
@@ -2725,14 +2745,14 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_ExtChase)
 	// Now that A_Chase can handle state label parameters, this function has become rather useless...
 	A_DoChase(stack, self, false,
 		domelee ? self->MeleeState : NULL, domissile ? self->MissileState : NULL,
-		playactive, nightmarefast, false);
+		playactive, nightmarefast, false, 0);
 	return 0;
 }
 
 // for internal use
 void A_Chase(VMFrameStack *stack, AActor *self)
-{
-	A_DoChase(stack, self, false, self->MeleeState, self->MissileState, true, gameinfo.nightmarefast, false);
+{
+	A_DoChase(stack, self, false, self->MeleeState, self->MissileState, true, gameinfo.nightmarefast, false, 0);
 }
 
 //=============================================================================
diff --git a/src/p_enemy.h b/src/p_enemy.h
index 2b6b7fe5e1..8b78b1cac9 100644
--- a/src/p_enemy.h
+++ b/src/p_enemy.h
@@ -61,7 +61,6 @@ void A_Weave(AActor *self, int xyspeed, int zspeed, fixed_t xydist, fixed_t zdis
 void A_Unblock(AActor *self, bool drop);
 
 DECLARE_ACTION(A_Look)
-DECLARE_ACTION(A_Wander)
 DECLARE_ACTION(A_BossDeath)
 DECLARE_ACTION(A_Pain)
 DECLARE_ACTION(A_MonsterRail)
@@ -70,10 +69,11 @@ DECLARE_ACTION(A_Scream)
 DECLARE_ACTION(A_FreezeDeath)
 DECLARE_ACTION(A_FreezeDeathChunks)
 void A_BossDeath(AActor *self);
-
+
+void A_Wander(AActor *self, int flags = 0);
 void A_Chase(VMFrameStack *stack, AActor *self);
 void A_FaceTarget(AActor *actor);
-void A_Face(AActor *self, AActor *other, angle_t max_turn = 0, angle_t max_pitch = ANGLE_270, angle_t ang_offset = 0, angle_t pitch_offset = 0, int flags = 0, fixed_t z_add = 0);
+void A_Face(AActor *self, AActor *other, angle_t max_turn = 0, angle_t max_pitch = ANGLE_270, angle_t ang_offset = 0, angle_t pitch_offset = 0, int flags = 0, fixed_t z_add = 0);
 
 bool A_RaiseMobj (AActor *, fixed_t speed);
 bool A_SinkMobj (AActor *, fixed_t speed);
diff --git a/src/p_floor.cpp b/src/p_floor.cpp
index 35e5273837..c632e8ba27 100644
--- a/src/p_floor.cpp
+++ b/src/p_floor.cpp
@@ -478,7 +478,7 @@ bool EV_DoFloor (DFloor::EFloor floortype, line_t *line, int tag,
 			(floor->m_Direction<0 && floor->m_FloorDestDist<sec->floorplane.d) ||	// moving down but going up
 			(floor->m_Speed >= abs(sec->floorplane.d - floor->m_FloorDestDist)))	// moving in one step
 		{
-			floor->StopInterpolation();
+			floor->StopInterpolation(true);
 
 			// [Graf Zahl]
 			// Don't make sounds for instant movement hacks but make an exception for
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 6c95fd6f8f..6416e0a6ef 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -4222,9 +4222,9 @@ void P_RailAttack(AActor *source, int damage, int offset_xy, fixed_t offset_z, i
 	rail_data.Caller = source;
 	
 	rail_data.StopAtOne = !!(railflags & RAF_NOPIERCE);
-	start.X = FIXED2FLOAT(xy.x);
-	start.Y = FIXED2FLOAT(xy.y);
-	start.Z = FIXED2FLOAT(shootz);
+	start.X = FIXED2DBL(xy.x);
+	start.Y = FIXED2DBL(xy.y);
+	start.Z = FIXED2DBL(shootz);
 
 	int flags;
 
diff --git a/src/p_maputl.cpp b/src/p_maputl.cpp
index 07ce97cca2..e5bb2bea27 100644
--- a/src/p_maputl.cpp
+++ b/src/p_maputl.cpp
@@ -560,7 +560,7 @@ sector_t *AActor::LinkToWorldForMapThing ()
 					DPrintf ("%s at (%d,%d) lies on %s line %td, distance = %f\n",
 						this->GetClass()->TypeName.GetChars(), X()>>FRACBITS, Y()>>FRACBITS, 
 						ldef->dx == 0? "vertical" :	ldef->dy == 0? "horizontal" : "diagonal",
-						ldef-lines, FIXED2FLOAT(distance));
+						ldef-lines, FIXED2DBL(distance));
 					angle_t finean = R_PointToAngle2 (0, 0, ldef->dx, ldef->dy);
 					if (ldef->backsector != NULL && ldef->backsector == ssec->sector)
 					{
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index dde1c80b88..658fcbc69c 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -5875,7 +5875,7 @@ AActor *P_SpawnMissileXYZ (fixed_t x, fixed_t y, fixed_t z,
 	// Answer: No, because this way, you can set up sets of parallel missiles.
 
 	fixedvec3 fixvel = source->Vec3To(dest);
-	FVector3 velocity(fixvel.x, fixvel.y, fixvel.z);
+	TVector3<double> velocity(fixvel.x, fixvel.y, fixvel.z);
 	// Floor and ceiling huggers should never have a vertical component to their velocity
 	if (th->flags3 & (MF3_FLOORHUGGER|MF3_CEILINGHUGGER))
 	{
@@ -5887,9 +5887,9 @@ AActor *P_SpawnMissileXYZ (fixed_t x, fixed_t y, fixed_t z,
 		velocity.Z += (dest->height - z + source->Z());
 	}
 	velocity.Resize (speed);
-	th->velx = (fixed_t)(velocity.X);
-	th->vely = (fixed_t)(velocity.Y);
-	th->velz = (fixed_t)(velocity.Z);
+	th->velx = xs_CRoundToInt(velocity.X);
+	th->vely = xs_CRoundToInt(velocity.Y);
+	th->velz = xs_CRoundToInt(velocity.Z);
 
 	// invisible target: rotate velocity vector in 2D
 	// [RC] Now monsters can aim at invisible player as if they were fully visible.
@@ -6163,16 +6163,16 @@ AActor *P_SpawnPlayerMissile (AActor *source, fixed_t x, fixed_t y, fixed_t z,
 	vz = -finesine[pitch>>ANGLETOFINESHIFT];
 	speed = MissileActor->Speed;
 
-	FVector3 vec(vx, vy, vz);
+	TVector3<double> vec(vx, vy, vz);
 
 	if (MissileActor->flags3 & (MF3_FLOORHUGGER|MF3_CEILINGHUGGER))
 	{
 		vec.Z = 0;
 	}
 	vec.Resize(speed);
-	MissileActor->velx = (fixed_t)vec.X;
-	MissileActor->vely = (fixed_t)vec.Y;
-	MissileActor->velz = (fixed_t)vec.Z;
+	MissileActor->velx = xs_CRoundToInt(vec.X);
+	MissileActor->vely = xs_CRoundToInt(vec.Y);
+	MissileActor->velz = xs_CRoundToInt(vec.Z);
 
 	if (MissileActor->flags4 & MF4_SPECTRAL)
 	{
@@ -6507,7 +6507,7 @@ DDropItem *AActor::GetDropItems() const
 fixed_t AActor::GetGravity() const
 {
 	if (flags & MF_NOGRAVITY) return 0;
-	return fixed_t(level.gravity * Sector->gravity * FIXED2FLOAT(gravity) * 81.92);
+	return fixed_t(level.gravity * Sector->gravity * FIXED2DBL(gravity) * 81.92);
 }
 
 // killough 11/98:
@@ -6631,13 +6631,13 @@ void PrintMiscActorInfo(AActor *query)
 		for (flagi = 0; flagi <= 31; flagi++)
 			if (query->flags7 & ActorFlags7::FromInt(1<<flagi)) Printf(" %s", FLAG_NAME(1<<flagi, flags7));
 		Printf("\nBounce flags: %x\nBounce factors: f:%f, w:%f", 
-			query->BounceFlags.GetValue(), FIXED2FLOAT(query->bouncefactor),
-			FIXED2FLOAT(query->wallbouncefactor));
+			query->BounceFlags.GetValue(), FIXED2DBL(query->bouncefactor),
+			FIXED2DBL(query->wallbouncefactor));
 		/*for (flagi = 0; flagi < 31; flagi++)
 			if (query->BounceFlags & 1<<flagi) Printf(" %s", flagnamesb[flagi]);*/
 		Printf("\nRender style = %i:%s, alpha %f\nRender flags: %x", 
 			querystyle, (querystyle < STYLE_Count ? renderstyles[querystyle] : "Unknown"),
-			FIXED2FLOAT(query->alpha), query->renderflags.GetValue());
+			FIXED2DBL(query->alpha), query->renderflags.GetValue());
 		/*for (flagi = 0; flagi < 31; flagi++)
 			if (query->renderflags & 1<<flagi) Printf(" %s", flagnamesr[flagi]);*/
 		Printf("\nSpecial+args: %s(%i, %i, %i, %i, %i)\nspecial1: %i, special2: %i.",
@@ -6646,10 +6646,10 @@ void PrintMiscActorInfo(AActor *query)
 			query->args[4],	query->special1, query->special2);
 		Printf("\nTID: %d", query->tid);
 		Printf("\nCoord= x: %f, y: %f, z:%f, floor:%f, ceiling:%f.",
-			FIXED2FLOAT(query->X()), FIXED2FLOAT(query->Y()), FIXED2FLOAT(query->Z()),
-			FIXED2FLOAT(query->floorz), FIXED2FLOAT(query->ceilingz));
+			FIXED2DBL(query->X()), FIXED2DBL(query->Y()), FIXED2DBL(query->Z()),
+			FIXED2DBL(query->floorz), FIXED2DBL(query->ceilingz));
 		Printf("\nSpeed= %f, velocity= x:%f, y:%f, z:%f, combined:%f.\n",
-			FIXED2FLOAT(query->Speed), FIXED2FLOAT(query->velx), FIXED2FLOAT(query->vely), FIXED2FLOAT(query->velz),
-			sqrt(pow(FIXED2FLOAT(query->velx), 2) + pow(FIXED2FLOAT(query->vely), 2) + pow(FIXED2FLOAT(query->velz), 2)));
+			FIXED2DBL(query->Speed), FIXED2DBL(query->velx), FIXED2DBL(query->vely), FIXED2DBL(query->velz),
+			sqrt(pow(FIXED2DBL(query->velx), 2) + pow(FIXED2DBL(query->vely), 2) + pow(FIXED2DBL(query->velz), 2)));
 	}
 }
diff --git a/src/p_slopes.cpp b/src/p_slopes.cpp
index a3db265261..3e402f73a1 100644
--- a/src/p_slopes.cpp
+++ b/src/p_slopes.cpp
@@ -75,17 +75,17 @@ static void P_SlopeLineToPoint (int lineid, fixed_t x, fixed_t y, fixed_t z, boo
 			plane = &sec->floorplane;
 		}
 
-		FVector3 p, v1, v2, cross;
+		TVector3<double> p, v1, v2, cross;
 
-		p[0] = FIXED2FLOAT (line->v1->x);
-		p[1] = FIXED2FLOAT (line->v1->y);
-		p[2] = FIXED2FLOAT (plane->ZatPoint (line->v1->x, line->v1->y));
-		v1[0] = FIXED2FLOAT (line->dx);
-		v1[1] = FIXED2FLOAT (line->dy);
-		v1[2] = FIXED2FLOAT (plane->ZatPoint (line->v2->x, line->v2->y)) - p[2];
-		v2[0] = FIXED2FLOAT (x - line->v1->x);
-		v2[1] = FIXED2FLOAT (y - line->v1->y);
-		v2[2] = FIXED2FLOAT (z) - p[2];
+		p[0] = FIXED2DBL (line->v1->x);
+		p[1] = FIXED2DBL (line->v1->y);
+		p[2] = FIXED2DBL (plane->ZatPoint (line->v1->x, line->v1->y));
+		v1[0] = FIXED2DBL (line->dx);
+		v1[1] = FIXED2DBL (line->dy);
+		v1[2] = FIXED2DBL (plane->ZatPoint (line->v2->x, line->v2->y)) - p[2];
+		v2[0] = FIXED2DBL (x - line->v1->x);
+		v2[1] = FIXED2DBL (y - line->v1->y);
+		v2[2] = FIXED2DBL (z) - p[2];
 
 		cross = v1 ^ v2;
 		double len = cross.Length();
@@ -187,23 +187,23 @@ void P_SetSlope (secplane_t *plane, bool setCeil, int xyangi, int zangi,
 	}
 	xyang = (angle_t)Scale (xyangi, ANGLE_90, 90 << ANGLETOFINESHIFT);
 
-	FVector3 norm;
+	TVector3<double> norm;
 
 	if (ib_compatflags & BCOMPATF_SETSLOPEOVERFLOW)
 	{
-		norm[0] = float(finecosine[zang] * finecosine[xyang]);
-		norm[1] = float(finecosine[zang] * finesine[xyang]);
+		norm[0] = double(finecosine[zang] * finecosine[xyang]);
+		norm[1] = double(finecosine[zang] * finesine[xyang]);
 	}
 	else
 	{
-		norm[0] = float(finecosine[zang]) * float(finecosine[xyang]);
-		norm[1] = float(finecosine[zang]) * float(finesine[xyang]);
+		norm[0] = double(finecosine[zang]) * double(finecosine[xyang]);
+		norm[1] = double(finecosine[zang]) * double(finesine[xyang]);
 	}
-	norm[2] = float(finesine[zang]) * 65536.f;
+	norm[2] = double(finesine[zang]) * 65536.f;
 	norm.MakeUnit();
-	plane->a = (int)(norm[0] * 65536.f);
-	plane->b = (int)(norm[1] * 65536.f);
-	plane->c = (int)(norm[2] * 65536.f);
+	plane->a = FLOAT2FIXED(norm[0]);
+	plane->b = FLOAT2FIXED(norm[1]);
+	plane->c = FLOAT2FIXED(norm[2]);
 	//plane->ic = (int)(65536.f / norm[2]);
 	plane->ic = DivScale32 (1, plane->c);
 	plane->d = -TMulScale16 (plane->a, x,
@@ -226,17 +226,17 @@ void P_VavoomSlope(sector_t * sec, int id, fixed_t x, fixed_t y, fixed_t z, int
 
 		if (l->args[0]==id)
 		{
-			FVector3 v1, v2, cross;
+			TVector3<double> v1, v2, cross;
 			secplane_t *srcplane = (which == 0) ? &sec->floorplane : &sec->ceilingplane;
 			fixed_t srcheight = (which == 0) ? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling);
 
-			v1[0] = FIXED2FLOAT (x - l->v2->x);
-			v1[1] = FIXED2FLOAT (y - l->v2->y);
-			v1[2] = FIXED2FLOAT (z - srcheight);
+			v1[0] = FIXED2DBL (x - l->v2->x);
+			v1[1] = FIXED2DBL (y - l->v2->y);
+			v1[2] = FIXED2DBL (z - srcheight);
 			
-			v2[0] = FIXED2FLOAT (x - l->v1->x);
-			v2[1] = FIXED2FLOAT (y - l->v1->y);
-			v2[2] = FIXED2FLOAT (z - srcheight);
+			v2[0] = FIXED2DBL (x - l->v1->x);
+			v2[1] = FIXED2DBL (y - l->v1->y);
+			v2[2] = FIXED2DBL (z - srcheight);
 
 			cross = v1 ^ v2;
 			double len = cross.Length();
@@ -334,8 +334,8 @@ static void P_SetSlopesFromVertexHeights(FMapThing *firstmt, FMapThing *lastmt,
 			sector_t *sec = &sectors[i];
 			if (sec->linecount != 3) continue;	// only works with triangular sectors
 
-			FVector3 vt1, vt2, vt3, cross;
-			FVector3 vec1, vec2;
+			TVector3<double> vt1, vt2, vt3, cross;
+			TVector3<double> vec1, vec2;
 			int vi1, vi2, vi3;
 
 			vi1 = int(sec->lines[0]->v1 - vertexes);
@@ -343,12 +343,12 @@ static void P_SetSlopesFromVertexHeights(FMapThing *firstmt, FMapThing *lastmt,
 			vi3 = (sec->lines[1]->v1 == sec->lines[0]->v1 || sec->lines[1]->v1 == sec->lines[0]->v2)?
 				int(sec->lines[1]->v2 - vertexes) : int(sec->lines[1]->v1 - vertexes);
 
-			vt1.X = FIXED2FLOAT(vertexes[vi1].x);
-			vt1.Y = FIXED2FLOAT(vertexes[vi1].y);
-			vt2.X = FIXED2FLOAT(vertexes[vi2].x);
-			vt2.Y = FIXED2FLOAT(vertexes[vi2].y);
-			vt3.X = FIXED2FLOAT(vertexes[vi3].x);
-			vt3.Y = FIXED2FLOAT(vertexes[vi3].y);
+			vt1.X = FIXED2DBL(vertexes[vi1].x);
+			vt1.Y = FIXED2DBL(vertexes[vi1].y);
+			vt2.X = FIXED2DBL(vertexes[vi2].x);
+			vt2.Y = FIXED2DBL(vertexes[vi2].y);
+			vt3.X = FIXED2DBL(vertexes[vi3].x);
+			vt3.Y = FIXED2DBL(vertexes[vi3].y);
 
 			for(int j=0; j<2; j++)
 			{
@@ -358,10 +358,10 @@ static void P_SetSlopesFromVertexHeights(FMapThing *firstmt, FMapThing *lastmt,
 				fixed_t z3;
 				if (h1==NULL && h2==NULL && h3==NULL) continue;
 
-				vt1.Z = FIXED2FLOAT(h1? *h1 : j==0? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling));
-				vt2.Z = FIXED2FLOAT(h2? *h2 : j==0? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling));
+				vt1.Z = FIXED2DBL(h1? *h1 : j==0? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling));
+				vt2.Z = FIXED2DBL(h2? *h2 : j==0? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling));
 				z3 = h3? *h3 : j==0? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling);
-				vt3.Z = FIXED2FLOAT(z3);
+				vt3.Z = FIXED2DBL(z3);
 
 				if (P_PointOnLineSidePrecise(vertexes[vi3].x, vertexes[vi3].y, sec->lines[0]) == 0)
 				{
@@ -374,7 +374,7 @@ static void P_SetSlopesFromVertexHeights(FMapThing *firstmt, FMapThing *lastmt,
 					vec2 = vt2 - vt3;
 				}
 
-				FVector3 cross = vec1 ^ vec2;
+				TVector3<double> cross = vec1 ^ vec2;
 
 				double len = cross.Length();
 				if (len == 0)
@@ -519,7 +519,7 @@ static void P_AlignPlane (sector_t *sec, line_t *line, int which)
 
 	refsec = line->frontsector == sec ? line->backsector : line->frontsector;
 
-	FVector3 p, v1, v2, cross;
+	TVector3<double> p, v1, v2, cross;
 
 	secplane_t *srcplane;
 	fixed_t srcheight, destheight;
@@ -528,15 +528,15 @@ static void P_AlignPlane (sector_t *sec, line_t *line, int which)
 	srcheight = (which == 0) ? sec->GetPlaneTexZ(sector_t::floor) : sec->GetPlaneTexZ(sector_t::ceiling);
 	destheight = (which == 0) ? refsec->GetPlaneTexZ(sector_t::floor) : refsec->GetPlaneTexZ(sector_t::ceiling);
 
-	p[0] = FIXED2FLOAT (line->v1->x);
-	p[1] = FIXED2FLOAT (line->v1->y);
-	p[2] = FIXED2FLOAT (destheight);
-	v1[0] = FIXED2FLOAT (line->dx);
-	v1[1] = FIXED2FLOAT (line->dy);
+	p[0] = FIXED2DBL (line->v1->x);
+	p[1] = FIXED2DBL(line->v1->y);
+	p[2] = FIXED2DBL(destheight);
+	v1[0] = FIXED2DBL(line->dx);
+	v1[1] = FIXED2DBL(line->dy);
 	v1[2] = 0;
-	v2[0] = FIXED2FLOAT (refvert->x - line->v1->x);
-	v2[1] = FIXED2FLOAT (refvert->y - line->v1->y);
-	v2[2] = FIXED2FLOAT (srcheight - destheight);
+	v2[0] = FIXED2DBL(refvert->x - line->v1->x);
+	v2[1] = FIXED2DBL(refvert->y - line->v1->y);
+	v2[2] = FIXED2DBL(srcheight - destheight);
 
 	cross = (v1 ^ v2).Unit();
 
diff --git a/src/p_user.cpp b/src/p_user.cpp
index 59098e83a3..d5f89576bd 100644
--- a/src/p_user.cpp
+++ b/src/p_user.cpp
@@ -2749,13 +2749,13 @@ void P_PredictionLerpReset()
 
 bool P_LerpCalculate(PredictPos from, PredictPos to, PredictPos &result, float scale)
 {
-	FVector3 vecFrom(FIXED2DBL(from.x), FIXED2DBL(from.y), FIXED2DBL(from.z));
-	FVector3 vecTo(FIXED2DBL(to.x), FIXED2DBL(to.y), FIXED2DBL(to.z));
-	FVector3 vecResult;
+	TVector3<double> vecFrom(FIXED2DBL(from.x), FIXED2DBL(from.y), FIXED2DBL(from.z));
+	TVector3<double> vecTo(FIXED2DBL(to.x), FIXED2DBL(to.y), FIXED2DBL(to.z));
+	TVector3<double> vecResult;
 	vecResult = vecTo - vecFrom;
 	vecResult *= scale;
 	vecResult = vecResult + vecFrom;
-	FVector3 delta = vecResult - vecTo;
+	TVector3<double> delta = vecResult - vecTo;
 
 	result.x = FLOAT2FIXED(vecResult.X);
 	result.y = FLOAT2FIXED(vecResult.Y);
diff --git a/src/r_data/r_interpolate.cpp b/src/r_data/r_interpolate.cpp
index 5f2632737b..4e0781a98a 100644
--- a/src/r_data/r_interpolate.cpp
+++ b/src/r_data/r_interpolate.cpp
@@ -344,9 +344,10 @@ int DInterpolation::AddRef()
 //
 //==========================================================================
 
-int DInterpolation::DelRef()
+int DInterpolation::DelRef(bool force)
 {
 	if (refcount > 0) --refcount;
+	if (force && refcount == 0) Destroy();
 	return refcount;
 }
 
@@ -943,20 +944,6 @@ DInterpolation *sector_t::SetInterpolation(int position, bool attach)
 //
 //==========================================================================
 
-void sector_t::StopInterpolation(int position)
-{
-	if (interpolations[position] != NULL)
-	{
-		interpolations[position]->DelRef();
-	}
-}
-
-//==========================================================================
-//
-//
-//
-//==========================================================================
-
 DInterpolation *FPolyObj::SetInterpolation()
 {
 	if (interpolation != NULL)
diff --git a/src/r_data/r_interpolate.h b/src/r_data/r_interpolate.h
index 29e8a61712..92e74c3f29 100644
--- a/src/r_data/r_interpolate.h
+++ b/src/r_data/r_interpolate.h
@@ -25,7 +25,7 @@ protected:
 
 public:
 	int AddRef();
-	int DelRef();
+	int DelRef(bool force = false);
 
 	virtual void Destroy();
 	virtual void UpdateInterpolation() = 0;
diff --git a/src/r_defs.h b/src/r_defs.h
index ce358dab30..fda3ab37f7 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -543,7 +543,6 @@ struct sector_t
 	sector_t *GetHeightSec() const;
 
 	DInterpolation *SetInterpolation(int position, bool attach);
-	void StopInterpolation(int position);
 
 	ASkyViewpoint *GetSkyBox(int which);
 
diff --git a/src/r_main.cpp b/src/r_main.cpp
index 883ab13dc9..90b8d865bd 100644
--- a/src/r_main.cpp
+++ b/src/r_main.cpp
@@ -714,15 +714,15 @@ void R_EnterPortal (PortalDrawseg* pds, int depth)
 		{ // any mirror--use floats to avoid integer overflow
 			vertex_t *v2 = pds->src->v2;
 
-			float dx = FIXED2FLOAT(v2->x - v1->x);
-			float dy = FIXED2FLOAT(v2->y - v1->y);
-			float x1 = FIXED2FLOAT(v1->x);
-			float y1 = FIXED2FLOAT(v1->y);
-			float x = FIXED2FLOAT(startx);
-			float y = FIXED2FLOAT(starty);
+			double dx = FIXED2DBL(v2->x - v1->x);
+			double dy = FIXED2DBL(v2->y - v1->y);
+			double x1 = FIXED2DBL(v1->x);
+			double y1 = FIXED2DBL(v1->y);
+			double x = FIXED2DBL(startx);
+			double y = FIXED2DBL(starty);
 
 			// the above two cases catch len == 0
-			float r = ((x - x1)*dx + (y - y1)*dy) / (dx*dx + dy*dy);
+			double r = ((x - x1)*dx + (y - y1)*dy) / (dx*dx + dy*dy);
 
 			viewx = FLOAT2FIXED((x1 + r * dx)*2 - x);
 			viewy = FLOAT2FIXED((y1 + r * dy)*2 - y);
diff --git a/src/r_plane.cpp b/src/r_plane.cpp
index e535230086..f1deceb9fa 100644
--- a/src/r_plane.cpp
+++ b/src/r_plane.cpp
@@ -1652,12 +1652,12 @@ void R_DrawTiltedPlane (visplane_t *pl, fixed_t alpha, bool additive, bool maske
 		return;
 	}
 
-	double vx = FIXED2FLOAT(viewx);
-	double vy = FIXED2FLOAT(viewy);
-	double vz = FIXED2FLOAT(viewz);
+	double vx = FIXED2DBL(viewx);
+	double vy = FIXED2DBL(viewy);
+	double vz = FIXED2DBL(viewz);
 
-	lxscale = FIXED2FLOAT(pl->xscale) * ifloatpow2[ds_xbits];
-	lyscale = FIXED2FLOAT(pl->yscale) * ifloatpow2[ds_ybits];
+	lxscale = FIXED2DBL(pl->xscale) * ifloatpow2[ds_xbits];
+	lyscale = FIXED2DBL(pl->yscale) * ifloatpow2[ds_ybits];
 	xscale = 64.f / lxscale;
 	yscale = 64.f / lyscale;
 	zeroheight = pl->height.ZatPoint(vx, vy);
diff --git a/src/r_things.cpp b/src/r_things.cpp
index 407bf54c7a..1179c7291a 100644
--- a/src/r_things.cpp
+++ b/src/r_things.cpp
@@ -1631,8 +1631,8 @@ void R_DrawRemainingPlayerSprites()
 			screen->DrawTexture(vis->pic,
 				viewwindowx + VisPSpritesX1[i],
 				viewwindowy + viewheight/2 - (vis->texturemid / 65536.0) * (vis->yscale / 65536.0) - 0.5,
-				DTA_DestWidthF, FIXED2FLOAT(vis->pic->GetWidth() * vis->xscale),
-				DTA_DestHeightF, FIXED2FLOAT(vis->pic->GetHeight() * vis->yscale),
+				DTA_DestWidthF, FIXED2DBL(vis->pic->GetWidth() * vis->xscale),
+				DTA_DestHeightF, FIXED2DBL(vis->pic->GetHeight() * vis->yscale),
 				DTA_Translation, TranslationToTable(vis->Translation),
 				DTA_FlipX, flip,
 				DTA_TopOffset, 0,
diff --git a/src/s_sound.cpp b/src/s_sound.cpp
index 6baaa5c655..dabed23f6e 100644
--- a/src/s_sound.cpp
+++ b/src/s_sound.cpp
@@ -63,10 +63,6 @@
 #define O_BINARY 0
 #endif
 
-#ifndef FIXED2FLOAT
-#define FIXED2FLOAT(f)			(((float)(f))/(float)65536)
-#endif
-
 #define NORM_PITCH				128
 #define NORM_PRIORITY			64
 #define NORM_SEP				0
diff --git a/src/thingdef/thingdef_codeptr.cpp b/src/thingdef/thingdef_codeptr.cpp
index a3f7c08878..e4744c8b48 100644
--- a/src/thingdef/thingdef_codeptr.cpp
+++ b/src/thingdef/thingdef_codeptr.cpp
@@ -250,6 +250,43 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, CountInv)
 	return 0;
 }
 
+//==========================================================================
+//
+// GetDistance
+//
+// NON-ACTION function to get the distance in double.
+//
+//==========================================================================
+DEFINE_ACTION_FUNCTION_PARAMS(AActor, GetDistance)
+{
+	if (numret > 0)
+	{
+		assert(ret != NULL);
+		PARAM_PROLOGUE;
+		PARAM_OBJECT(self, AActor);
+		PARAM_BOOL(checkz);
+		PARAM_INT_OPT(ptr) { ptr = AAPTR_TARGET; }
+
+		AActor *target = COPY_AAPTR(self, ptr);
+
+		if (!target || target == self)
+		{
+			ret->SetFloat(0);
+		}
+		else
+		{
+			fixedvec3 diff = self->Vec3To(target);
+			if (checkz)
+				diff.z += (target->height - self->height) / 2;
+
+			const double length = TVector3<double>(FIXED2DBL(diff.x), FIXED2DBL(diff.y), (checkz) ? FIXED2DBL(diff.z) : 0).Length();
+			ret->SetFloat(length);
+		}
+		return 1;
+	}
+	return 0;
+}
+
 //==========================================================================
 //
 // A_RearrangePointers
@@ -1150,8 +1187,8 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CustomMissile)
 				{
 					if (CMF_OFFSETPITCH & flags)
 					{
-							FVector2 velocity (missile->velx, missile->vely);
-							pitch += R_PointToAngle2(0,0, (fixed_t)velocity.Length(), missile->velz);
+							TVector2<double> velocity (missile->velx, missile->vely);
+							pitch += R_PointToAngle2(0,0, xs_CRoundToInt(velocity.Length()), missile->velz);
 					}
 					ang = pitch >> ANGLETOFINESHIFT;
 					missilespeed = abs(FixedMul(finecosine[ang], missile->Speed));
@@ -1159,8 +1196,8 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CustomMissile)
 				}
 				else
 				{
-					FVector2 velocity (missile->velx, missile->vely);
-					missilespeed = (fixed_t)velocity.Length();
+					TVector2<double> velocity (missile->velx, missile->vely);
+					missilespeed = xs_CRoundToInt(velocity.Length());
 				}
 
 				if (CMF_SAVEPITCH & flags)
@@ -1566,8 +1603,8 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_FireCustomMissile)
 			{
 				// This original implementation is to aim straight ahead and then offset
 				// the angle from the resulting direction. 
-				FVector3 velocity(misl->velx, misl->vely, 0);
-				fixed_t missilespeed = (fixed_t)velocity.Length();
+				TVector3<double> velocity(misl->velx, misl->vely, 0);
+				fixed_t missilespeed = xs_CRoundToInt(velocity.Length());
 				misl->angle += angle;
 				angle_t an = misl->angle >> ANGLETOFINESHIFT;
 				misl->velx = FixedMul (missilespeed, finecosine[an]);
@@ -3235,7 +3272,7 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CountdownArg)
 	PARAM_INT(argnum);
 	PARAM_STATE_OPT(state)	{ state = self->FindState(NAME_Death); }
 
-	if (argnum > 0 && argnum < (int)countof(self->args))
+	if (argnum >= 0 && argnum < (int)countof(self->args))
 	{
 		if (!self->args[argnum]--)
 		{
@@ -6714,8 +6751,8 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_FaceMovementDirection)
 	if (!(flags & FMDF_NOPITCH))
 	{
 		fixed_t current = mobj->pitch;
-		const FVector2 velocity(mobj->velx, mobj->vely);
-		const fixed_t pitch = R_PointToAngle2(0, 0, (fixed_t)velocity.Length(), -mobj->velz);
+		const TVector2<double> velocity(mobj->velx, mobj->vely);
+		const fixed_t pitch = R_PointToAngle2(0, 0, xs_CRoundToInt(velocity.Length()), -mobj->velz);
 		if (pitchlimit > 0)
 		{
 			// [MC] angle_t for pitchlimit was required because otherwise
diff --git a/src/thingdef/thingdef_exp.cpp b/src/thingdef/thingdef_exp.cpp
index e8a043d31a..17d97e4fa8 100644
--- a/src/thingdef/thingdef_exp.cpp
+++ b/src/thingdef/thingdef_exp.cpp
@@ -467,7 +467,8 @@ static FxExpression *ParseExpression0 (FScanner &sc, PClassActor *cls)
 			PFunction *func = dyn_cast<PFunction>(cls->Symbols.FindSymbol(identifier, true));
 			try
 			{
-				if (func != NULL)
+				// There is an action function ACS_NamedExecuteWithResult which must be ignored here for this to work.
+				if (func != NULL && identifier != NAME_ACS_NamedExecuteWithResult)
 				{
 					sc.UnGet();
 					ParseFunctionParameters(sc, cls, *args, func, "", NULL);
diff --git a/src/v_draw.cpp b/src/v_draw.cpp
index ce502c772e..12e42ec0bd 100644
--- a/src/v_draw.cpp
+++ b/src/v_draw.cpp
@@ -781,10 +781,10 @@ void DCanvas::VirtualToRealCoordsFixed(fixed_t &x, fixed_t &y, fixed_t &w, fixed
 {
 	double dx, dy, dw, dh;
 
-	dx = FIXED2FLOAT(x);
-	dy = FIXED2FLOAT(y);
-	dw = FIXED2FLOAT(w);
-	dh = FIXED2FLOAT(h);
+	dx = FIXED2DBL(x);
+	dy = FIXED2DBL(y);
+	dw = FIXED2DBL(w);
+	dh = FIXED2DBL(h);
 	VirtualToRealCoords(dx, dy, dw, dh, vwidth, vheight, vbottom, handleaspect);
 	x = FLOAT2FIXED(dx);
 	y = FLOAT2FIXED(dy);
@@ -1184,8 +1184,8 @@ void DCanvas::FillSimplePoly(FTexture *tex, FVector2 *points, int npoints,
 		return;
 	}
 
-	scalex /= FIXED2FLOAT(tex->xScale);
-	scaley /= FIXED2FLOAT(tex->yScale);
+	scalex /= FIXED2DBL(tex->xScale);
+	scaley /= FIXED2DBL(tex->yScale);
 
 	cosrot = cos(rot);
 	sinrot = sin(rot);
diff --git a/wadsrc/static/actors/actor.txt b/wadsrc/static/actors/actor.txt
index c25c1492b0..48ee9f68fd 100644
--- a/wadsrc/static/actors/actor.txt
+++ b/wadsrc/static/actors/actor.txt
@@ -41,6 +41,7 @@ ACTOR Actor native //: Thinker
 	native bool CheckClass(class<Actor> checkclass, int ptr_select = AAPTR_DEFAULT, bool match_superclass = false);
 	native bool IsPointerEqual(int ptr_select1, int ptr_select2);
 	native int	CountInv(class<Inventory> itemtype, int ptr_select = AAPTR_DEFAULT);
+	native float GetDistance(bool checkz, int ptr = AAPTR_DEFAULT);
 
 	// Action functions
 	// Meh, MBF redundant functions. Only for DeHackEd support.
@@ -149,7 +150,7 @@ ACTOR Actor native //: Thinker
 	action native A_SkullPop(class<PlayerChunk> skulltype = "BloodySkull");
 	action native A_CheckPlayerDone();
 
-	action native A_Wander();
+	action native A_Wander(int flags = 0);
 	action native A_Look2();
 	action native A_TossGib();
 	action native A_SentinelBob();
diff --git a/wadsrc/static/actors/constants.txt b/wadsrc/static/actors/constants.txt
index 1fd824989b..e5733e0338 100644
--- a/wadsrc/static/actors/constants.txt
+++ b/wadsrc/static/actors/constants.txt
@@ -79,11 +79,20 @@ const int SXF_ISMASTER				=	1 << 27;
 const int SXF_ISTRACER				=	1 << 28;
 
 // Flags for A_Chase
-const int CHF_FASTCHASE = 1;
-const int CHF_NOPLAYACTIVE = 2;
-const int CHF_NIGHTMAREFAST = 4;
-const int CHF_RESURRECT = 8;
-const int CHF_DONTMOVE = 16;
+enum
+{
+	CHF_FASTCHASE =						1,
+	CHF_NOPLAYACTIVE =					2,
+	CHF_NIGHTMAREFAST =					4,
+	CHF_RESURRECT =						8,
+	CHF_DONTMOVE =						16,
+	CHF_NORANDOMTURN =					32,
+	CHF_NODIRECTIONTURN =				64,
+	CHF_NOPOSTATTACKTURN =				128,
+	CHF_STOPIFBLOCKED =					256,
+
+	CHF_DONTTURN = CHF_NORANDOMTURN | CHF_NOPOSTATTACKTURN | CHF_STOPIFBLOCKED
+};
 
 // Flags for A_LookEx
 const int LOF_NOSIGHTCHECK = 1;