[winswitch] Scrolling with mouse wheel not working

[Antoine Martin]

(snip)
>>> Ok. When I use scroll up using the mouse wheel I get tons of these messages:
>>>
>>> 2017-02-02 17:28:29,496 mousewheel: orientation=vertical distance=30.0, units=0, new value=0.0, keys=0x0, x=439, y=360, client=gtk2.client, wid=218
>>>
>>> When I scrool down (the one that works) the messages are slightly different:
>>>
>>> 2017-02-02 17:29:41,362 mousewheel: send 1 wheel events to the server for distance=-120, remainder=0
>>> 2017-02-02 17:29:41,382 mousewheel: orientation=vertical distance=-30.0, units=-1, new value=-30.0, keys=0x0, x=434, y=375, client=gtk2.client, wid=218
>> MS Windows clients have extra code for handling scrolling acceleration:
>> https://xpra.org/trac/ticket/1131
>>
>> The "distance" is accumulated until we reach 120. (this is a MS Windows
>> constant)
>>
>> It looks like your system uses a non-standard vertical acceleration set
>> to just 30 (4 times slower than normal), so it may take 4 wheel scroll
>> steps to generate one scroll event server side. (and up to 7 events if
>> you had already scrolled 3 events in the opposite direction)
> 
> But wouldn't this mean that if I scroll long enough up, it would eventually generate an event?
> It does not. No matter how long I scroll, xev never generates any output when scrolling upwards.
It should. The "distance" should accumulate with every event until it
reaches 120.
You only provided a single event log message, so we don't know what is
happening with those values.

> Furthermore:
> 1.) If I use Xming server and execute "xpra attach :1000" from within SSH session, everything works. (So it works on the same system with a different X server)
I'm not sure exactly what you mean here.
The MS Windows client does not use an X11 server at all.
> 2.) It does not work with 4 different mice (2x USB, 1x Bluetooth, 1x RF/USB)
> 3.) In the control panel under Mouse -> Wheel, the Vertical and Horizontal scrolling setting were the same (3). I set both of them to 1. No difference
> 4.) Unfortunately (because less reproducible) - it works in Win7 VM in VirtualBox on the same machine.
Works fine here in VM and with a full Windows 7 test system.

>> This code could be improved to tiemout or at least reset the distance
>> when the scrolling changes direction. Feel free to file a ticket for it.
> 
> Given 1-3 - do you still think this is the case?
> I would then create a ticket referencing this conversation.
It could be a different issue, difficult to say.
In any case, these sort of problems are best tracked using tickets.

Cheers
Antoine