python tkinter: how to work with pixels?

It is indeed tricky --I thought you had to use a Canvas widget, but that has no access to Pixels either.Image items embedded in the Canvas do have, though. The Tkinter.PhotoImage classdoes have a "put" method that accepts a color in hex format and pixel coordinates:

from tkinter import Tk, Canvas, PhotoImage, mainloopfrom math import sinWIDTH, HEIGHT = 640, 480window = Tk()canvas = Canvas(window, width=WIDTH, height=HEIGHT, bg="#000000")canvas.pack()img = PhotoImage(width=WIDTH, height=HEIGHT)canvas.create_image((WIDTH/2, HEIGHT/2), image=img, state="normal")for x in range(4 * WIDTH):    y = int(HEIGHT/2 + HEIGHT/4 * sin(x/80.0))    img.put("#ffffff", (x//4,y))mainloop()

The good news is that even it being done this way, the updates are "live":you set pixels on the image, and see them showing up on screen.

This should be much faster than the way drawing higher level lines on screen -but for lots of pixels it still will be slow, due to a Python function call needed forevery pixel. Any other pure python way of manipulating pixels directly will suffer from that - the only way out is calling primitives that manipulate several pixels at a time in native code from your Python code.

A nice cross-platform library for getting 2d drawing, however poorly documented as wellis Cairo - it would should have much better primitives than Tkinter's Canvas or PhotoImage.

Don't forget to save a reference after canvas.create_image. In some cases, especially when working with the PIL module, python will garbage-collect the image, even though it is being displayed!Syntax is something likecanvas.create_image((WIDTH/2, HEIGHT/2), image=img)canvas.image = img