Demo/threads/wpi.py

   1 # Display digits of pi in a window, calculating in a separate thread.
   2 # Compare ../scripts/pi.py.
   3
   4 import sys
   5 import time
   6 import thread
   7 import stdwin
   8 from stdwinevents import *
   9
  10 ok = 1
  11
  12 digits = []
  13
  14 def worker():
  15         k, a, b, a1, b1 = 2l, 4l, 1l, 12l, 4l
  16         while ok:
  17                 # Next approximation
  18                 p, q, k = k*k, 2l*k+1l, k+1l
  19                 a, b, a1, b1 = a1, b1, p*a+q*a1, p*b+q*b1
  20                 # Print common digits
  21                 d, d1 = a/b, a1/b1
  22                 #print a, b, a1, b1
  23                 while d == d1:
  24                         digits.append(`int(d)`)
  25                         a, a1 = 10l*(a%b), 10l*(a1%b1)
  26                         d, d1 = a/b, a1/b1
  27
  28 def main():
  29         global ok
  30         digits_seen = 0
  31         thread.start_new_thread(worker, ())
  32         tw = stdwin.textwidth('0 ')
  33         lh = stdwin.lineheight()
  34         stdwin.setdefwinsize(20 * tw, 20 * lh)
  35         stdwin.setdefscrollbars(0, 1)
  36         win = stdwin.open('digits of pi')
  37         options = win.menucreate('Options')
  38         options.additem('Auto scroll')
  39         autoscroll = 1
  40         options.check(0, autoscroll)
  41         while 1:
  42                 win.settimer(1)
  43                 type, w, detail = stdwin.getevent()
  44                 if type == WE_CLOSE:
  45                         ok = 0
  46                         sys.exit(0)
  47                 elif type == WE_DRAW:
  48                         (left, top), (right, bottom) = detail
  49                         digits_seen = len(digits)
  50                         d = win.begindrawing()
  51                         for i in range(digits_seen):
  52                                 h = (i % 20) * tw
  53                                 v = (i / 20) * lh
  54                                 if top-lh < v < bottom:
  55                                         d.text((h, v), digits[i])
  56                         d.close()
  57                 elif type == WE_TIMER:
  58                         n = len(digits)
  59                         if n > digits_seen:
  60                                 win.settitle(`n` + ' digits of pi')
  61                                 d = win.begindrawing()
  62                                 for i in range(digits_seen, n):
  63                                         h = (i % 20) * tw
  64                                         v = (i / 20) * lh
  65                                         d.text((h, v), digits[i])
  66                                 d.close()
  67                                 digits_seen = n
  68                                 height = (v + 20*lh) / (20*lh) * (20*lh)
  69                                 win.setdocsize(0, height)
  70                                 if autoscroll:
  71                                         win.show((0, v), (h+tw, v+lh))
  72                 elif type == WE_MENU:
  73                         menu, item = detail
  74                         if menu == options:
  75                                 if item == 0:
  76                                         autoscroll = (not autoscroll)
  77                                         options.check(0, autoscroll)
  78
  79
  80 main()