@Wkot, to prevent the Who actor from sinking below the bottom of the screen, its y-coordinate must be kept below a point in the world that is half the actor's image height less than the world height. That expression gives that y-coordinate of the line that the center of the actor is not allowed to go beyond in the downward direction.
@Roshan123, move repetition and stalemate are both drawn games (so is draw by agreement, which is obviously not incorporated in this game). As for you 2nd comment, insufficient material was not implemented.
2023/5/14
Scroller Class Demos
2023/4/29
The Maze Factory
2023/2/19
Jump and Run Demo w/Moving Platform
2023/1/11
Private Messaging
2022/11/2
Private Messaging
2022/3/6
ChessWorld
2022/2/25
Strafer
2022/2/20
Great scenario
2022/2/20
Bounce Demo