Re: [TCLCORE] TIP 474: "Treat the mouse wheel events in a uniform way" again

[Brad L. <bra...@gm...>]

On Fri, Jun 29, 2018 at 9:44 AM, Griffin, Brian <bri...@me...>
wrote:

>
> When I use 2-finger swipe gesture I see, for example:
>
> WM_MOUSEHWHEEL fwKeys:0000 zDelta:-2 xPos:220 yPos:370 for horizontal
> swipe and
>
> WM_MOUSEWHEEL fwKeys:0000 zDelta:-2 xPos:220 yPos:370 for vertical swipe.
>
>
>
> Interestingly, direction is decided by the initial motion and stays, even
> if the swipe changes orientation.  So, if I start the swipe to the left,
> the initial message is mouseHwheel, and all subsequent messages are also
> Hwheel, even if my fingers start moving up.  And vis-versa, starting out
> with a downward swipe gives MouseWheel as the first message and all
> subsequent messages, even if the swipe changes direction to the left.  In
> order to change direction I have to stop and lift my fingers off the touch
> pad.
>
>
>
> This differs from the Mac, where a diagonal swipe generates both
> button-4/5 & button-6/7 events.
>
>
>
> And lastly, not surprisingly, I get no Button-(4,5,6,7) events in Tk.
>
>
> This is correct.  WM_[VH]SCROLL are messages from the scrollbar itself.
MOUSEHWHEEL is the one that needs implementation.

I think the Windows design is better -- you can adjust the horizontal (or
vertical) position without
affecting the other axis.  Useful in image processing programs when you
want to adjust something
without messing up the other axis.

But the Mac method is understandable also.  Meta keys could be used to
constrain which
axis is affected.