# Tk_seq_shuffle_2.py

# Tk_seq_shuffle_2.py

from tkinter import *
from PIL import Image, ImageTk
from itertools import combinations

ww = 600
hh = 600

def draw():
    image.putdata(rgb)
    photo = ImageTk.PhotoImage(image)
    canvas.create_image(0,0,image=photo,anchor=NW)
    canvas.update()


root = Tk()
root.title("Tk_seq_shuffle")
root.geometry("%dx%d+0+0"%(ww,hh))

canvas = Canvas(root, width=ww, height=hh)
canvas.pack()

image = Image.new("RGB", (ww,hh), (255,255,255))

rainbow=[]
def z(r,g,b):
    rainbow.append((r,g,b))
r,g,b=255,0,0
for g in range(256):
    z(r,g,b)
for r in range(254, -1, -1):
    z(r,g,b)
for b in range(256):
    z(r,g,b)
for g in range(254, -1, -1):
    z(r,g,b)
for r in range(256):
    z(r,g,b)
for b in range(254, -1, -1):
    z(r,g,b)
L = len(rainbow)

i = 1
rgb = [(0,0,0)]*(ww*hh)

while 1:
    ttt = []
    for x in range(ww):
        i += 1
        t = rainbow.pop(i%L)
        ttt += [t]
        rainbow += [t]
    rgb.extend(ttt)
    rgb = rgb[-ww*hh:]
    draw()