#  Random Spirals
#
#  Press the space bar to repeat.
#  Press "q" to quit.

link random
link turtle
link graphics

procedure main()

   WOpen("size=400,400") | stop("*** cannot open window")
   randomize()

   spiral()
   repeat case Event() of {
      "q":  exit()
      " ":  spiral()
      }
end

procedure spiral()
   local angle, incr, side
   
   TReset()
   angle := 30 + ?149
   incr := sqrt(4 * ?0) + 0.3
   side := 0
   while side < 270 do {
      TDraw(side +:= incr)
      TRight(angle)
      }
   return
end