[Idle-dev] Dragging Window Not Smooth

[Roger Serwy]

On 08/15/12 10:58, Terry Reedy wrote:
> On 8/15/2012 11:06 AM, Weeble wrote:
>> I hadn't noticed it before, but I started Idle 3.2 on Windows 7 and
>> observed it does not move smoothly. Other editors (e.g. I tried GVIM
>> and Notepad) move smoothly when dragged by their title bar. I'd guess
>> they're hitting at least 30fps, probably quite a bit better. Idle has
>> quite jerky movement. I'd guess maybe 10fps. So far as I can tell,
>> this affects all Idle windows, but *only* while the shell window is
>> open. If you have open only a document window, it's smooth and snappy
>> like any other editor.
>
> Confirmed with 3.3.0b1, Win7, 64 bit, fast, year-old machine and 
> graphics, including change in edit window behavior with and without 
> shell window. I have not seen anything like this with any other 
> program. If I move window quickly, it seems to jump about 1/4 inch at 
> a time.
>
I'm not seeing this problem with Arch Linux under Gnome 3. Try running 
IDLE without a subprocess to see if the dragging behavior still occurs.

The shell window, (PyShell instance) polls the subprocess every 50 ms 
which may be the source of the delay. Search for "self.pollinterval" in 
PyShell.py to adjust this value. My guess is that higher values will 
cause the dragging to be more responsive.

The Tk eventloop may be stalling during this poll which may then be 
preventing the movement of the window. I don't know enough of how Tk and 
Win7 interact for window placement to be sure, however.

- Roger