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ON TIMER(n) Statement Programming Example
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ON TIMER(n) Statement Programming Example
 
Here is a program that draws a polygon every three seconds with a random
shape (three to seven sides), size, and location:
 
SCREEN 1
DEFINT A-Z
DIM X(6), Y(6)
TIMER ON            'Enable timer event trapping.
ON TIMER(3) GOSUB Drawpoly    'Draw a new polygon every
                              'three seconds.
PRINT "Press any key to end program"
INPUT "Press <RETURN> to start",Test$
 
DO
LOOP WHILE INKEY$ = ""     'End program if any key pressed.
 
END
 
Drawpoly:
   CLS            'Erase old polygon.
   N = INT(5 * RND + 2)       'N is random number from 2 to 6.
   FOR I = 0 TO N
      X(I) = INT(RND * 319)   'Get coordinates of vertices of
      Y(I) = INT(RND * 199)   'polygon.
   NEXT
   PSET (X(N), Y(N))
   FOR I = 0 TO N
      LINE -(X(I), Y(I)),2    'Draw new polygon.
   NEXT
   RETURN