Understanding the coordinate system

To draw graphic items on a canvas, we will need to specify their position using a coordinate system. Since a canvas is a two-dimensional space, points will be notated by their coordinates on the horizontal and vertical axes—commonly labeledxand y respectively.

With a simple application, we can easily illustrate how to locate these points in relation to the origin of the coordinate system, placed in the upper-left corner of the canvas area.

How to do it...

The following program contains an empty canvas and a label that shows the location of the cursor on the canvas; you can move the cursor to see what position it is placed in, giving clear feedback on how the x and y coordinates increment or decrement, depending on the direction you move the mouse pointer:

import tkinter as tk

class App(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("Basic canvas")

        self.canvas = tk.Canvas(self, bg="white")
        self.label = tk.Label...