diff --git a/src/actor.h b/src/actor.h
index f58d48f9a1..f17af7bc2d 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -847,7 +847,7 @@ public:
 	bool intersects(AActor *other) const
 	{
 		fixed_t blockdist = radius + other->radius;
-		return ( abs(pos.x - other->pos.x) < blockdist && abs(pos.y - other->pos.y) < blockdist);
+		return ( abs(x - other->x) < blockdist && abs(y - other->y) < blockdist);
 	}
 
 	PalEntry GetBloodColor() const
@@ -888,84 +888,84 @@ public:
 	// to distinguish between portal-aware and portal-unaware distance calculation.
 	fixed_t AproxDistance(AActor *other, bool absolute = false)
 	{
-		return P_AproxDistance(pos.x - other->pos.x, pos.y - other->pos.y);
+		return P_AproxDistance(x - other->x, y - other->y);
 	}
 
 	// same with 'ref' here.
 	fixed_t AproxDistance(fixed_t otherx, fixed_t othery, AActor *ref = NULL)
 	{
-		return P_AproxDistance(pos.x - otherx, pos.y - othery);
+		return P_AproxDistance(x - otherx, y - othery);
 	}
 
 	fixed_t AproxDistance(AActor *other, fixed_t xadd, fixed_t yadd, bool absolute = false)
 	{
-		return P_AproxDistance(pos.x - other->pos.x + xadd, pos.y - other->pos.y + yadd);
+		return P_AproxDistance(x - other->x + xadd, y - other->y + yadd);
 	}
 
 	fixed_t AproxDistance3D(AActor *other, bool absolute = false)
 	{
-		return P_AproxDistance(AproxDistance(other), pos.z - other->pos.z);
+		return P_AproxDistance(AproxDistance(other), z - other->z);
 	}
 
 	// more precise, but slower version, being used in a few places
 	fixed_t Distance2D(AActor *other, bool absolute = false)
 	{
-		return xs_RoundToInt(FVector2(pos.x - other->pos.x, pos.y - other->pos.y).Length());
+		return xs_RoundToInt(FVector2(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(pos.x - other->pos.x, pos.y - other->pos.y, pos.z - other->pos.z).Length());
+		return xs_RoundToInt(FVector3(x - other->x, y - other->y, z - other->z).Length());
 	}
 
 	angle_t AngleTo(AActor *other, bool absolute = false) const
 	{
-		return R_PointToAngle2(pos.x, pos.y, other->pos.x, other->pos.y);
+		return R_PointToAngle2(x, y, other->x, other->y);
 	}
 
 	angle_t AngleTo(AActor *other, fixed_t oxofs, fixed_t oyofs, bool absolute = false) const
 	{
-		return R_PointToAngle2(pos.x, pos.y, other->pos.x + oxofs, other->pos.y + oyofs);
+		return R_PointToAngle2(x, y, other->x + oxofs, other->y + oyofs);
 	}
 
 	fixed_t AngleTo(fixed_t otherx, fixed_t othery, AActor *ref = NULL)
 	{
-		return R_PointToAngle2(pos.x, pos.y, otherx, othery);
+		return R_PointToAngle2(x, y, otherx, othery);
 	}
 
 	fixed_t AngleXYTo(fixed_t myx, fixed_t myy, AActor *other, bool absolute = false)
 	{
-		return R_PointToAngle2(myx, myy, other->pos.x, other->pos.y);
+		return R_PointToAngle2(myx, myy, other->x, other->y);
 	}
 
 	fixedvec2 Vec2To(AActor *other) const
 	{
-		fixedvec2 ret = { other->pos.x - pos.x, other->pos.y - pos.y };
+		fixedvec2 ret = { other->x - x, other->y - y };
 		return ret;
 	}
 
 	fixedvec3 Vec3To(AActor *other) const
 	{
-		fixedvec3 ret = { other->pos.x - pos.x, other->pos.y - pos.y, other->pos.z - pos.z };
+		fixedvec3 ret = { other->x - x, other->y - y, other->z - z };
 		return ret;
 	}
 
 	fixedvec2 Vec2Offset(fixed_t dx, fixed_t dy, bool absolute = false) const
 	{
-		fixedvec2 ret = { pos.x + dx, pos.y + dy };
+		fixedvec2 ret = { x + dx, y + dy };
 		return ret;
 	}
 
 	fixedvec3 Vec3Offset(fixed_t dx, fixed_t dy, fixed_t dz, bool absolute = false) const
 	{
-		fixedvec3 ret = { pos.x + dx, pos.y + dy, pos.z + dz };
+		fixedvec3 ret = { x + dx, y + dy, z + dz };
 		return ret;
 	}
 
 	void Move(fixed_t dx, fixed_t dy, fixed_t dz)
 	{
-		SetOrigin(pos.x + dx, pos.y + dy, pos.z + dz, true);
+		SetOrigin(x + dx, y + dy, z + dz, true);
 	}
 
 	inline void SetFriendPlayer(player_t *player);
@@ -987,10 +987,7 @@ public:
 
 // info for drawing
 // NOTE: The first member variable *must* be x.
-private:
-	fixedvec3		pos;
-public:
-	//fixed_t	 		x,y,z;
+	fixed_t	 		x,y,z;
 	AActor			*snext, **sprev;	// links in sector (if needed)
 	angle_t			angle;
 	WORD			sprite;				// used to find patch_t and flip value
@@ -1188,7 +1185,7 @@ public:
 	void LinkToWorld (sector_t *sector);
 	void UnlinkFromWorld ();
 	void AdjustFloorClip ();
-	void SetOrigin (fixed_t x, fixed_t y, fixed_t z, bool moving);
+	void SetOrigin (fixed_t x, fixed_t y, fixed_t z, bool moving = false);
 	bool InStateSequence(FState * newstate, FState * basestate);
 	int GetTics(FState * newstate);
 	bool SetState (FState *newstate, bool nofunction=false);
@@ -1220,19 +1217,23 @@ public:
 
 	fixed_t X() const
 	{
-		return pos.x;
+		return x;
 	}
 	fixed_t Y() const
 	{
-		return pos.y;
+		return y;
 	}
 	fixed_t Z() const
 	{
-		return pos.z;
+		return z;
 	}
-	void SetZ(fixed_t newz)
+	fixed_t Top() const
 	{
-		pos.z = newz;
+		return z + height;
+	}
+	void SetZ(fixed_t newz, bool moving = true)
+	{
+		z = newz;
 	}
 
 };
diff --git a/src/d_net.cpp b/src/d_net.cpp
index 95061d0e1f..29303fa04f 100644
--- a/src/d_net.cpp
+++ b/src/d_net.cpp
@@ -2376,7 +2376,7 @@ void Net_DoCommand (int type, BYTE **stream, int player)
 			s = ReadString (stream);
 
 			if (Trace (players[player].mo->X(), players[player].mo->Y(),
-				players[player].mo->Z() + players[player].mo->height - (players[player].mo->height>>2),
+				players[player].mo->Top() - (players[player].mo->height>>2),
 				players[player].mo->Sector,
 				vx, vy, vz, 172*FRACUNIT, 0, ML_BLOCKEVERYTHING, players[player].mo,
 				trace, TRACE_NoSky))
diff --git a/src/p_3dfloors.cpp b/src/p_3dfloors.cpp
index abc4d5c595..e294dec692 100644
--- a/src/p_3dfloors.cpp
+++ b/src/p_3dfloors.cpp
@@ -337,7 +337,7 @@ void P_PlayerOnSpecial3DFloor(player_t* player)
 		{
 			//Water and DEATH FOG!!! heh
 			if (player->mo->Z() > rover->top.plane->ZatPoint(player->mo) || 
-				(player->mo->Z() + player->mo->height) < rover->bottom.plane->ZatPoint(player->mo))
+				player->mo->Top() < rover->bottom.plane->ZatPoint(player->mo))
 				continue;
 		}
 
diff --git a/src/p_acs.cpp b/src/p_acs.cpp
index 6ce1cfd55d..81420b73ac 100644
--- a/src/p_acs.cpp
+++ b/src/p_acs.cpp
@@ -4158,7 +4158,7 @@ bool DLevelScript::DoCheckActorTexture(int tid, AActor *activator, int string, b
 	}
 	else
 	{
-		fixed_t z = actor->Z() + actor->height;
+		fixed_t z = actor->Top();
 		// Looking through planes from bottom to top
 		for (i = numff-1; i >= 0; --i)
 		{
diff --git a/src/p_enemy.cpp b/src/p_enemy.cpp
index 77999c06eb..15861f79e8 100644
--- a/src/p_enemy.cpp
+++ b/src/p_enemy.cpp
@@ -243,9 +243,9 @@ bool AActor::CheckMeleeRange ()
 	// [RH] Don't melee things too far above or below actor.
 	if (!(flags5 & MF5_NOVERTICALMELEERANGE))
 	{
-		if (pl->Z() > Z() + height)
+		if (pl->Z() > Top())
 			return false;
-		if (pl->Z() + pl->height < Z())
+		if (pl->Top() < Z())
 			return false;
 	}
 
@@ -280,11 +280,11 @@ bool P_CheckMeleeRange2 (AActor *actor)
 	{
 		return false;
 	}
-	if (mo->Z() > actor->Z()+actor->height)
+	if (mo->Z() > actor->Top())
 	{ // Target is higher than the attacker
 		return false;
 	}
-	else if (actor->Z() > mo->Z()+mo->height)
+	else if (actor->Z() > mo->Top())
 	{ // Attacker is higher
 		return false;
 	}
@@ -2787,7 +2787,7 @@ void A_Face (AActor *self, AActor *other, angle_t max_turn, angle_t max_pitch, a
 
 		// If the target z is above the target's head, reposition to the middle of
 		// its body.		
-		if (target_z >= other->Z() + other->height)
+		if (target_z >= other->Top())
 		{
 			target_z = other->Z() + (other->height / 2);
 		}
diff --git a/src/p_lnspec.cpp b/src/p_lnspec.cpp
index 2592c930f6..06e2f5f215 100644
--- a/src/p_lnspec.cpp
+++ b/src/p_lnspec.cpp
@@ -3107,7 +3107,7 @@ FUNC(LS_GlassBreak)
 			{
 				glass = Spawn("GlassJunk", x, y, ONFLOORZ, ALLOW_REPLACE);
 
-				glass->SetZ(glass->z + 24 * FRACUNIT);
+				glass->SetZ(glass->Z() + 24 * FRACUNIT);
 				glass->SetState (glass->SpawnState + (pr_glass() % glass->health));
 				an = pr_glass() << (32-8);
 				glass->angle = an;
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 78a17df109..69f8b6c5be 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -190,7 +190,7 @@ static bool PIT_FindFloorCeiling(line_t *ld, const FBoundingBox &box, FCheckPosi
 		}
 		else if (r >= (1 << 24))
 		{
-			P_LineOpening(open, tmf.thing, ld, sx = ld->v2->x, sy = ld->v2->y, tmf.thing->x, tmf.thing->y, flags);
+			P_LineOpening(open, tmf.thing, ld, sx = ld->v2->x, sy = ld->v2->y, tmf.thing->X(), tmf.thing->Y(), flags);
 		}
 		else
 		{
@@ -288,9 +288,9 @@ void P_FindFloorCeiling(AActor *actor, int flags)
 	FCheckPosition tmf;
 
 	tmf.thing = actor;
-	tmf.x = actor->x;
-	tmf.y = actor->y;
-	tmf.z = actor->z;
+	tmf.x = actor->X();
+	tmf.y = actor->Y();
+	tmf.z = actor->Z();
 
 	if (flags & FFCF_ONLYSPAWNPOS)
 	{
@@ -336,7 +336,7 @@ void P_FindFloorCeiling(AActor *actor, int flags)
 
 	if (tmf.touchmidtex) tmf.dropoffz = tmf.floorz;
 
-	if (!(flags & FFCF_ONLYSPAWNPOS) || (tmf.abovemidtex && (tmf.floorz <= actor->z)))
+	if (!(flags & FFCF_ONLYSPAWNPOS) || (tmf.abovemidtex && (tmf.floorz <= actor->Z())))
 	{
 		actor->floorz = tmf.floorz;
 		actor->dropoffz = tmf.dropoffz;
@@ -404,13 +404,13 @@ bool P_TeleportMove(AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefra
 	line_t *ld;
 
 	// P_LineOpening requires the thing's z to be the destination z in order to work.
-	fixed_t savedz = thing->z;
-	thing->z = z;
+	fixed_t savedz = thing->Z();
+	thing->SetZ(z);
 	while ((ld = it.Next()))
 	{
 		PIT_FindFloorCeiling(ld, box, tmf, 0);
 	}
-	thing->z = savedz;
+	thing->SetZ(savedz);
 
 	if (tmf.touchmidtex) tmf.dropoffz = tmf.floorz;
 
@@ -427,7 +427,7 @@ bool P_TeleportMove(AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefra
 			continue;
 
 		fixed_t blockdist = th->radius + tmf.thing->radius;
-		if (abs(th->x - tmf.x) >= blockdist || abs(th->y - tmf.y) >= blockdist)
+		if (abs(th->X() - tmf.x) >= blockdist || abs(th->Y() - tmf.y) >= blockdist)
 			continue;
 
 		// [RH] Z-Check
@@ -437,8 +437,8 @@ bool P_TeleportMove(AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefra
 		{
 			if (!(th->flags3 & thing->flags3 & MF3_DONTOVERLAP))
 			{
-				if (z > th->z + th->height ||	// overhead
-					z + thing->height < th->z)	// underneath
+				if (z > th->Top() ||	// overhead
+					z + thing->height < th->Z())	// underneath
 					continue;
 			}
 		}
@@ -459,7 +459,7 @@ bool P_TeleportMove(AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefra
 	if (modifyactor)
 	{
 		// the move is ok, so link the thing into its new position
-		thing->SetOrigin(x, y, z);
+		thing->SetOrigin(x, y, z, false);
 		thing->floorz = tmf.floorz;
 		thing->ceilingz = tmf.ceilingz;
 		thing->floorsector = tmf.floorsector;
@@ -507,7 +507,7 @@ bool P_TeleportMove(AActor *thing, fixed_t x, fixed_t y, fixed_t z, bool telefra
 void P_PlayerStartStomp(AActor *actor)
 {
 	AActor *th;
-	FBlockThingsIterator it(FBoundingBox(actor->x, actor->y, actor->radius));
+	FBlockThingsIterator it(FBoundingBox(actor->X(), actor->Y(), actor->radius));
 
 	while ((th = it.Next()))
 	{
@@ -525,9 +525,9 @@ void P_PlayerStartStomp(AActor *actor)
 		if (th->player == NULL && !(th->flags3 & MF3_ISMONSTER))
 			continue;
 
-		if (actor->z > th->z + th->height)
+		if (actor->Z() > th->Top())
 			continue;        // overhead
-		if (actor->z + actor->height < th->z)
+		if (actor->Top() < th->Z())
 			continue;        // underneath
 
 		P_DamageMobj(th, actor, actor, TELEFRAG_DAMAGE, NAME_Telefrag);