diff --git a/source/core/gameinput.cpp b/source/core/gameinput.cpp
index 26521fb2f..169685b37 100644
--- a/source/core/gameinput.cpp
+++ b/source/core/gameinput.cpp
@@ -364,7 +364,7 @@ FSerializer& Serialize(FSerializer& arc, const char* keyname, PlayerHorizon& w,
 
 		if (arc.isReading())
 		{
-			w.ohoriz = w.ZzHORIZON;
+			w.ZzOLDHORIZON = w.ZzHORIZON;
 			w.ohorizoff = w.horizoff;
 			w.inputdisabled = w.inputdisabled;
 			w.resetadjustment();
diff --git a/source/core/gameinput.h b/source/core/gameinput.h
index bb0bf21d1..c74cd2ec1 100644
--- a/source/core/gameinput.h
+++ b/source/core/gameinput.h
@@ -8,7 +8,7 @@
 
 struct PlayerHorizon
 {
-	DAngle ZzHORIZON, ohoriz, horizoff, ohorizoff;
+	DAngle ZzHORIZON, ZzOLDHORIZON, horizoff, ohorizoff;
 
 	friend FSerializer& Serialize(FSerializer& arc, const char* keyname, PlayerHorizon& w, PlayerHorizon* def);
 
@@ -19,17 +19,17 @@ struct PlayerHorizon
 	// Interpolation helpers.
 	void backup()
 	{
-		ohoriz = ZzHORIZON;
+		ZzOLDHORIZON = ZzHORIZON;
 		ohorizoff = horizoff;
 	}
 	void restore()
 	{
-		ZzHORIZON = ohoriz;
+		ZzHORIZON = ZzOLDHORIZON;
 		horizoff = ohorizoff;
 	}
 
 	// Commonly used getters.
-	DAngle osum() { return ohoriz + ohorizoff; }
+	DAngle osum() { return ZzOLDHORIZON + ohorizoff; }
 	DAngle sum() { return ZzHORIZON + horizoff; }
 	DAngle interpolatedsum(double const interpfrac) { return interpolatedvalue(osum(), sum(), interpfrac); }
 
@@ -67,7 +67,7 @@ struct PlayerHorizon
 		else
 		{
 			ZzHORIZON = value;
-			if (backup) ohoriz = ZzHORIZON;
+			if (backup) ZzOLDHORIZON = ZzHORIZON;
 		}
 	}
 
diff --git a/source/games/duke/src/gameexec.cpp b/source/games/duke/src/gameexec.cpp
index c15a4e06a..3b71fbe30 100644
--- a/source/games/duke/src/gameexec.cpp
+++ b/source/games/duke/src/gameexec.cpp
@@ -350,7 +350,7 @@ void DoPlayer(bool bSet, int lVar1, int lLabelID, int lVar2, DDukeActor* sActor,
 		break;
 
 	case PLAYER_OHORIZ:
-		if (!bSet) SetGameVarID(lVar2, int(ps[iPlayer].horizon.ohoriz.Tan() * -128.), sActor, sPlayer);
+		if (!bSet) SetGameVarID(lVar2, int(ps[iPlayer].horizon.ZzOLDHORIZON.Tan() * -128.), sActor, sPlayer);
 		break;
 
 	case PLAYER_HORIZOFF:
@@ -2247,7 +2247,7 @@ int ParseState::parse(void)
 
 			ps[g_p].last_extra = g_ac->spr.extra = gs.max_player_health;
 			ps[g_p].wantweaponfire = -1;
-			ps[g_p].horizon.ohoriz = ps[g_p].horizon.ZzHORIZON = nullAngle;
+			ps[g_p].horizon.ZzOLDHORIZON = ps[g_p].horizon.ZzHORIZON = nullAngle;
 			ps[g_p].on_crane = nullptr;
 			ps[g_p].frag_ps = g_p;
 			ps[g_p].horizon.ohorizoff = ps[g_p].horizon.horizoff = nullAngle;
diff --git a/source/games/duke/src/premap.cpp b/source/games/duke/src/premap.cpp
index 874bc83f6..34c55b660 100644
--- a/source/games/duke/src/premap.cpp
+++ b/source/games/duke/src/premap.cpp
@@ -125,7 +125,7 @@ void resetplayerstats(int snum)
 	p->footprintpal     = 0;
 	p->footprintshade   = 0;
 	p->jumping_toggle   = 0;
-	p->horizon.ohoriz = p->horizon.ZzHORIZON = DAngle::fromDeg(-17.354);
+	p->horizon.ZzOLDHORIZON = p->horizon.ZzHORIZON = DAngle::fromDeg(-17.354);
 	p->horizon.ohorizoff = p->horizon.horizoff = nullAngle;
 	p->bobcounter       = 0;
 	p->on_ground        = 0;
diff --git a/source/games/exhumed/src/player.cpp b/source/games/exhumed/src/player.cpp
index c60dcd582..48b0aae76 100644
--- a/source/games/exhumed/src/player.cpp
+++ b/source/games/exhumed/src/player.cpp
@@ -407,7 +407,7 @@ void RestartPlayer(int nPlayer)
 
     plr->nThrust.Zero();
 
-	plr->nDestVertPan = plr->horizon.ohoriz = plr->horizon.ZzHORIZON = nullAngle;
+	plr->nDestVertPan = plr->horizon.ZzOLDHORIZON = plr->horizon.ZzHORIZON = nullAngle;
 	plr->nBreathTimer = 90;
 
 	plr->nTauntTimer = RandomSize(3) + 3;
@@ -503,7 +503,7 @@ void StartDeathSeq(int nPlayer, int nVal)
 
     StopFiringWeapon(nPlayer);
 
-    PlayerList[nPlayer].horizon.ohoriz = PlayerList[nPlayer].horizon.ZzHORIZON = nullAngle;
+    PlayerList[nPlayer].horizon.ZzOLDHORIZON = PlayerList[nPlayer].horizon.ZzHORIZON = nullAngle;
     pActor->oviewzoffset = pActor->viewzoffset = -55;
     PlayerList[nPlayer].nInvisible = 0;
     dVertPan[nPlayer] = 15;
diff --git a/source/games/sw/src/player.cpp b/source/games/sw/src/player.cpp
index e96caa958..c1809d169 100644
--- a/source/games/sw/src/player.cpp
+++ b/source/games/sw/src/player.cpp
@@ -7048,7 +7048,7 @@ void InitAllPlayers(void)
     for (pp = Player; pp < &Player[MAX_SW_PLAYERS]; pp++)
     {
         pp->angle.ang = pp->angle.oang = pfirst->angle.ang;
-        pp->horizon.ZzHORIZON = pp->horizon.ohoriz = pfirst->horizon.ZzHORIZON;
+        pp->horizon.ZzHORIZON = pp->horizon.ZzOLDHORIZON = pfirst->horizon.ZzHORIZON;
         pp->cursector = pfirst->cursector;
         // set like this so that player can trigger something on start of the level
         pp->lastcursector = pfirst->cursector+1;