SET WINDOW -100,100,-100,100
FOR i=-90 TO 90 STEP 10
   DRAW disk  WITH SCALE(2)*SHIFT(i,0)
NEXT i
WAIT DELAY 3
FOR i=0 TO 1000
   SET DRAW mode hidden ! ちらつき防止の特殊処理(1)
   CLEAR
   FOR j=-90 TO 90 STEP 10
      DRAW disk  WITH SCALE(2)*SHIFT(j+i*j/100,0)
   NEXT j
   WAIT DELAY 0.01
   SET DRAW mode explicit ! ちらつき防止の特殊処理(2)
NEXT i
END