Angle, Direction | 
 
  right (0 pi, that is 0 degrees)  
  right up (1/4 pi, that is 45 degrees)  
  up (1/2 pi, that is 90 degrees)  
  left up (3/4 pi, that is 135 degrees)  
  left (1 pi, that is 180 degrees)  
  left down (1 1/4 pi, that is 225 degrees)  
  down (1 1/2 pi, that is 270 degrees)  
  right down (1 3/4 pi, that is 315 degrees)  
 
The angle elements are numeric constants representing the angle (direction) expressed in radian (the perigon, 360 degrees is 2*pi, i.e. approximately 6.28). The angle elements can be used e.g. as a goniometric function parameter or a parameter for setting the sprite direction (e.g. of Peter or Lucy).
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