[Tkinter-discuss] Moving object on page leaves afterimage on Python 3 but not on 2

[Michael Lange]

Hi,

On Thu, 4 Feb 2016 14:58:11 +0200
Reinis Danne <rei4dan at gmail.com> wrote:

> To test:
> $ git clone https://gitlab.com/bkchem/bkchem.git
> $ cd bkchem
> $ git submodule init
> $ git submodule update
> $ python3 bkchem/bkchem.py

this looks like quite a complex piece of code. Is it possible for you to
provide a simpler example that exhibits the problem?
Some additional information might also be helpful to track down the
problem:
* which platform are you running (Windows / X / Mac)?
* do your Python 2 / 3 versions share the same Tk version?
* which Tk version(s) do you use?

Without having reviewed the code I can only try a quick shot in the dark:
maybe Python 2 and 3 do *not* use the same Tk and these Tk versions
behave slightly differently. Maybe inserting additional calls to
update_idletasks() here and there might help. At a quick glance the
redraw() method in your graphics module might be a candidate for this.
Have you already tried that?

Best regards

Michael

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