Backport 'A_FaceConsolePlayer' from zandronum.

By Dusk, who authorized me to do this.

src/thingdef/thingdef_codeptr.cpp

@@ -3781,6 +3781,36 @@ DEFINE_ACTION_FUNCTION(AActor, A_RaiseSiblings)
 	}
 }
 
+//===========================================================================
+//
+// [TP] A_FaceConsolePlayer
+//
+//===========================================================================
+DEFINE_ACTION_FUNCTION_PARAMS (AActor, A_FaceConsolePlayer) {
+	ACTION_PARAM_START (1);
+	ACTION_PARAM_ANGLE (MaxTurnAngle, 0);
+
+	angle_t		Angle;
+	angle_t		DeltaAngle;
+	AActor		*pConsolePlayer;
+
+	// Always watch the consoleplayer.
+	pConsolePlayer = players[consoleplayer].mo;
+	if (( playeringame[consoleplayer] == false ) || ( pConsolePlayer == NULL ))
+		return;
+
+	// Find the angle between the actor and the console player.
+	Angle = R_PointToAngle2( self->x, self->y, pConsolePlayer->x, pConsolePlayer->y );
+	DeltaAngle = Angle - self->angle;
+
+	if (( MaxTurnAngle == 0 ) || ( DeltaAngle < MaxTurnAngle ) || ( DeltaAngle > (unsigned)-MaxTurnAngle ))
+		self->angle = Angle;
+	else if ( DeltaAngle < ANG180 )
+		self->angle += MaxTurnAngle;
+	else
+		self->angle -= MaxTurnAngle;
+}
+
 //===========================================================================
 //
 // A_MonsterRefire

wadsrc/static/actors/actor.txt

@@ -186,6 +186,7 @@ ACTOR Actor native //: Thinker
 	action native A_ClearSoundTarget();
 	action native A_FireAssaultGun();
 	action native A_CheckTerrain();
+	action native A_FaceConsolePlayer(float MaxTurnAngle = 0); // [TP]
 
 	action native A_MissileAttack();
 	action native A_MeleeAttack();