Initial revision

Demo/tkinter/guido/electrons.py

+#!/ufs/guido/bin/sgi/tkpython
+# Simulate "electrons" migrating across the screen.  
+# An optional bitmap file in can be in the background.
+#
+# Usage: electrons [n [bitmapfile]]
+#
+# n is the number of electrons to animate; default is 4, maximum 15.
+#
+# The bitmap file can be any X11 bitmap file (look in
+# /usr/include/X11/bitmaps for samples); it is displayed as the
+# background of the animation.  Default is no bitmap.
+
+# This uses Steen Lumholt's Tk interface
+from Tkinter import *
+
+
+
+# The graphical interface
+class Electrons:
+
+	# Create our objects
+	def __init__(self, n, bitmap = None):
+		self.n = n
+		self.tk = tk = Tk()
+		self.canvas = c = Canvas(tk)
+		c.pack()
+		width, height = tk.getint(c['width']), tk.getint(c['height'])
+
+		# Add background bitmap
+		if bitmap:
+			self.bitmap = c.create_bitmap(width/2, height/2,
+						      {'bitmap': bitmap,
+						       'foreground': 'blue'})
+
+		self.pieces = {}
+		x1, y1, x2, y2 = 10,70,14,74
+		for i in range(n,0,-1):
+			p = c.create_oval(x1, y1, x2, y2,
+					       {'fill': 'red'})
+			self.pieces[i] = p
+			y1, y2 = y1 +2, y2 + 2
+		self.tk.update()
+
+	def random_move(self,n):
+		for i in range(1,n+1):
+			p = self.pieces[i]
+			c = self.canvas
+			import rand
+			x = rand.choice(range(-2,4))
+			y = rand.choice(range(-3,4))
+			c.move(p, x, y)
+		self.tk.update()
+	# Run -- never returns
+	def run(self):
+		while 1:
+			self.random_move(self.n)
+		self.tk.mainloop() # Hang around...
+
+# Main program
+def main():
+	import sys, string
+
+	# First argument is number of pegs, default 4
+	if sys.argv[1:]:
+		n = string.atoi(sys.argv[1])
+	else:
+		n = 30
+
+	# Second argument is bitmap file, default none
+	if sys.argv[2:]:
+		bitmap = sys.argv[2]
+		# Reverse meaning of leading '@' compared to Tk
+		if bitmap[0] == '@': bitmap = bitmap[1:]
+		else: bitmap = '@' + bitmap
+	else:
+		bitmap = None
+
+	# Create the graphical objects...
+	h = Electrons(n, bitmap)
+
+	# ...and run!
+	h.run()
+
+
+# Call main when run as script
+if __name__ == '__main__':
+	main()
+
+

Demo/tkinter/guido/hanoi.py

+# Animated Towers of Hanoi using Tk with optional bitmap file in
+# background.
+#
+# Usage: tkhanoi [n [bitmapfile]]
+#
+# n is the number of pieces to animate; default is 4, maximum 15.
+#
+# The bitmap file can be any X11 bitmap file (look in
+# /usr/include/X11/bitmaps for samples); it is displayed as the
+# background of the animation.  Default is no bitmap.
+
+# This uses Steen Lumholt's Tk interface
+from Tkinter import *
+
+
+# Basic Towers-of-Hanoi algorithm: move n pieces from a to b, using c
+# as temporary.  For each move, call report()
+def hanoi(n, a, b, c, report):
+	if n <= 0: return
+	hanoi(n-1, a, c, b, report)
+	report(n, a, b)
+	hanoi(n-1, c, b, a, report)
+
+
+# The graphical interface
+class Tkhanoi:
+
+	# Create our objects
+	def __init__(self, n, bitmap = None):
+		self.n = n
+		self.tk = tk = Tk()
+		self.canvas = c = Canvas(tk)
+		c.pack()
+		width, height = tk.getint(c['width']), tk.getint(c['height'])
+
+		# Add background bitmap
+		if bitmap:
+			self.bitmap = c.create_bitmap(width/2, height/2,
+						      {'bitmap': bitmap,
+						       'foreground': 'blue'})
+
+		# Generate pegs
+		pegwidth = 10
+		pegheight = height/2
+		pegdist = width/3
+		x1, y1 = (pegdist-pegwidth)/2, height*1/3
+		x2, y2 = x1+pegwidth, y1+pegheight
+		self.pegs = []
+		p = c.create_rectangle(x1, y1, x2, y2, {'fill': 'black'})
+		self.pegs.append(p)
+		x1, x2 = x1+pegdist, x2+pegdist
+		p = c.create_rectangle(x1, y1, x2, y2, {'fill': 'black'})
+		self.pegs.append(p)
+		x1, x2 = x1+pegdist, x2+pegdist
+		p = c.create_rectangle(x1, y1, x2, y2, {'fill': 'black'})
+		self.pegs.append(p)
+		self.tk.update()
+
+		# Generate pieces
+		pieceheight = pegheight/16
+		maxpiecewidth = pegdist*2/3
+		minpiecewidth = 2*pegwidth
+		self.pegstate = [[], [], []]
+		self.pieces = {}
+		x1, y1 = (pegdist-maxpiecewidth)/2, y2-pieceheight-2
+		x2, y2 = x1+maxpiecewidth, y1+pieceheight
+		dx = (maxpiecewidth-minpiecewidth) / (2*max(1, n-1))
+		for i in range(n, 0, -1):
+			p = c.create_rectangle(x1, y1, x2, y2,
+					       {'fill': 'red'})
+			self.pieces[i] = p
+			self.pegstate[0].append(i)
+			x1, x2 = x1 + dx, x2-dx
+			y1, y2 = y1 - pieceheight-2, y2-pieceheight-2
+			self.tk.update()
+			self.tk.after(25)
+
+	# Run -- never returns
+	def run(self):
+		while 1:
+			hanoi(self.n, 0, 1, 2, self.report)
+			hanoi(self.n, 1, 2, 0, self.report)
+			hanoi(self.n, 2, 0, 1, self.report)
+			hanoi(self.n, 0, 2, 1, self.report)
+			hanoi(self.n, 2, 1, 0, self.report)
+			hanoi(self.n, 1, 0, 2, self.report)
+
+	# Reporting callback for the actual hanoi function
+	def report(self, i, a, b):
+		if self.pegstate[a][-1] != i: raise RuntimeError # Assertion
+		del self.pegstate[a][-1]
+		p = self.pieces[i]
+		c = self.canvas
+
+		# Lift the piece above peg a
+		ax1, ay1, ax2, ay2 = c.bbox(self.pegs[a])
+		while 1:
+			x1, y1, x2, y2 = c.bbox(p)
+			if y2 < ay1: break
+			c.move(p, 0, -1)
+			self.tk.update()
+
+		# Move it towards peg b
+		bx1, by1, bx2, by2 = c.bbox(self.pegs[b])
+		newcenter = (bx1+bx2)/2
+		while 1:
+			x1, y1, x2, y2 = c.bbox(p)
+			center = (x1+x2)/2
+			if center == newcenter: break
+			if center > newcenter: c.move(p, -1, 0)
+			else: c.move(p, 1, 0)
+			self.tk.update()
+
+		# Move it down on top of the previous piece
+		pieceheight = y2-y1-2
+		newbottom = by2 - pieceheight*len(self.pegstate[b]) - 2
+		while 1:
+			x1, y1, x2, y2 = c.bbox(p)
+			if y2 >= newbottom: break
+			c.move(p, 0, 1)
+			self.tk.update()
+
+		# Update peg state
+		self.pegstate[b].append(i)
+
+
+# Main program
+def main():
+	import sys, string
+
+	# First argument is number of pegs, default 4
+	if sys.argv[1:]:
+		n = string.atoi(sys.argv[1])
+	else:
+		n = 4
+
+	# Second argument is bitmap file, default none
+	if sys.argv[2:]:
+		bitmap = sys.argv[2]
+		# Reverse meaning of leading '@' compared to Tk
+		if bitmap[0] == '@': bitmap = bitmap[1:]
+		else: bitmap = '@' + bitmap
+	else:
+		bitmap = None
+
+	# Create the graphical objects...
+	h = Tkhanoi(n, bitmap)
+
+	# ...and run!
+	h.run()
+
+
+# Call main when run as script
+if __name__ == '__main__':
+	main()