[Edu-sig] re: new graphics.py etc.

[Gregor Lingl]

Thanks, too, John!

By changing 2 or 3 lines in Kirbys code I arrived
at a tiny animation. (attachment). It's intended to
run from the command line.

Question: The raw_input() in line 70 seems to be
indispensable. It doesn't work without it. Why is
this the case?

Regards, Gregor

>  
>
-------------- next part --------------
"""

Kirby Urners nks.py using Tkinter with
tiny animation 


"""

# uncomment one or the other, reload if switching

from graphics import GraphWin, Point, Rectangle

class Canvas(object):

    def __init__(self, width, rows, pixelsize):
        self.pixelsize = pixelsize
        self.c = GraphWin('NKS',width*pixelsize, rows*pixelsize, False)
        self.c.setBackground('black')        

    def drawcell(self, thepoint):
        therow = thepoint[0]*self.pixelsize
        thecol = thepoint[1]*self.pixelsize

        therect = Rectangle(Point(therow, thecol),
                            Point(therow + self.pixelsize-1,
                              thecol + self.pixelsize-1))
        therect.setFill('yellow')
        therect.setOutline('yellow')            
        therect.draw(self.c)

    def showimage(self):
        self.c.flush()
        g = raw_input("Hit Enter on this line to close window")
        self.c.close()

def base2(n,pad=8):
    output = []
    while n > 1:
        digit = n%2
        n //= 2
        output.append(str(digit)) 
    output.append(str(n))
    output.reverse()
    return (''.join(output)).zfill(pad)

def makerule(n):
    therule = {}
    output  = base2(n)
    for i in range(8):
        therule[base2(7-i,3)] = output[i]
    return therule

def sayrule(themap):
    for i in range(7,-1,-1): 
        thekey = base2(i,3)
        print "%s --> %s" % (thekey, themap[thekey])

class Pattern(object):
    
    def __init__(self, n, width=40, rows=20, pixelsize = 1):
        self.width = width
        self.rule = makerule(n)
        self.therow = ('0' * (width//2) +
                       '1' +
                       '0' * (width - width//2 - 1))
        self.rownum = 0
        # Canvas imported from either of 2 modules
        self.canvas = Canvas(width,rows,pixelsize)
        self.canvas.c.flush()                           # <===
        raw_input("Hit Enter to start automaton!")      # <===

    def next(self):
        while True:
            yield self.therow
            for i in range(len(self.therow)):
                if self.therow[i]=='1':
                    self.canvas.drawcell((i,self.rownum))
                    
            newrow = ['0'] * len(self.therow)
            for i in range(1,len(self.therow)-1):            
                thekey = (self.therow[i-1] +
                          self.therow[i] +
                          self.therow[i + 1])
                newrow[i] = self.rule[thekey]
            self.therow = ''.join(newrow)
            self.rownum += 1

    def showimage(self):
        self.canvas.showimage()
            
    def __iter__(self):
        return self.next()
        
def t1(rule, width, height, pixelsize=1):
    p = Pattern(rule ,width, height, pixelsize)
    g = p.next()
    for i in range(width/2):
        g.next()
        p.canvas.c.flush()
    p.showimage()

if __name__ == '__main__':
    t1(30,200,100,4)