Polyobj_OR_RotateLeft
From ZDoom Wiki
90:Polyobj_OR_RotateLeft (po, speed, angle)
Rotates a polyobject right through the specified angle. If angle is 255, then the polyobject will rotate continuously and never stop.
po: polyobj to rotate speed: how quickly the polyobj should rotate angle: byte angle to rotate the polyobj through
The OR in this special stands for OverRide. Under normal circumstances, if a polyobject is doing something, you cannot make it do something else until it has finished whatever it is doing. This can be a problem with perpetual polyobjs (such as Polyobj_RotateLeft or Polyobj_RotateRight with a byte angle of 255). Using one of these four specials, you can force the polyobj to stop whatever it is doing and do something else.
