docs: def point_on_screen(self, pos):
          """
          Is the point still on the screen?
  
          :param pos: Point
          :type pos: tuple
          :return: Is it?
          :rtype: bool
          """
          if 0 <= pos[0] < self.width and 0 <= pos[1] < self.height:
              return True
          else:
              return False