tkinter animation speed on windows and linux - python-3.x

Question

I was trying to create simple 2d game using tkinter, but faced with interesting problem: animation speed is quite different on various computers.
To test this, I've create script, that measures time of animation
import tkinter as tk
import datetime
root = tk.Tk()
can = tk.Canvas(height=500, width=1000)
can.pack()
rect = can.create_rectangle(0, 240, 20, 260, fil='#5F6A6A')
def act():
global rect, can
pos = can.coords(rect)
if pos[2] < 1000:
can.move(rect, 5, 0)
can.update()
can.after(1)
act()
def key_down(key):
t = datetime.datetime.now()
act()
print(datetime.datetime.now() - t)
can.bind("<Button-1>", key_down)
root.mainloop()
and get these results:
i3-7100u ubuntu 20.04 laptop python3.8.5 - 0.5 seconds
i3-7100u windows 10 laptop python3.9.4 - 3 seconds
i3-6006u ubuntu 20.10 laptop python3.9.x - 0.5 seconds
i3-6006u windows 10 laptop python3.8.x - 3 seconds
i5-7200u windows 10 laptop python3.6.x - 3 seconds
i5-8400 windows 10 desktop python3.9.x - 3 seconds
fx-9830p windows 10 laptop python3.8.x - 0.5 seconds
tkinter vesrion is the same - 8.6
How can be it fixed or at least explained?

Answer 1

tkinter.Canvas.after should be used like so:
def act():
global rect, can
pos = can.coords(rect)
if pos[2] < 1000:
can.move(rect, 5, 0)
can.update()
can.after(1, act)
The after method is not like time.sleep. Rather than recursively calling the function, the above code schedules it to be called later, so this will break your timing code.
If you want to time it again, try this:
def act():
global rect, can, t
pos = can.coords(rect)
if pos[2] < 1000:
can.move(rect, 5, 0)
can.update()
can.after(1, act)
else:
print(datetime.datetime.now() - t)
def key_down(key):
global t
t = datetime.datetime.now()
act()
This may still take different amounts of time on different machines. This difference can be caused by a variety of things like CPU speed, the implementation of tkinter for your OS etc. The difference can be reduced by increasing the delay between iterations: tkinter.Canvas.after takes a time in milliseconds, so a delay of 16 can still give over 60 frames per seconds.
If keeping the animation speed constant is important, I would recommend you use delta time in your motion calculations rather than assuming a constant frame rate.

Answer 2

AS you can see from your data it doesent matter which python version. It appears that ubuntu systems can help process python easier. However, im pretty sure its just the processer or how much ram the computer has.