Re: Subject: w32 mouse wheel handling

[storm@cua.dk (Kim F. Storm)]

"Stefan Monnier" <monnier+gnu/emacs@rum.cs.yale.edu> writes:

> I agree on the principle, but I think using mouse-4 and mouse-5 is
> not correct.  It's just an X11 hack.  I'd rather create new events
> like wheel-up and wheel-down and then have a function-key-map to
> translate mouse-4 and mouse-5 to wheel-up and wheel-down (on X).

I agree 100%, that we should not use the mouse-4 and mouse-5 names.  

But I'm less certain about the names for the wheel events though.

I think the wheel-up and wheel-down names are a bit confusing when
compated to existing mouse events like down-mouse-1 and up-mouse-2.

Also, if you look at a typical mouse wheel, it has two directions:
"upwards" (turn the wheel away from yourself) and "downwards" (turn
the wheel towards yourself).  So in the "human context", these should
then correspond to the events wheel-up and wheel-down.  

But inside emacs, the event which scrolls the mouse "away from you"
would be bound to scroll-down and "towards you" to scroll-up, so in
the "emacs context" we could just as well justify to assign the
wheel-up and wheel-down events in the "opposite direction".

So "wheel-up" and "wheel-down" are not really unambiguous.

Furthermore, I have seen mice with two scroll wheels, some of these
have two up/down wheels, others have both up/down and left/right
wheels, and I think our naming of wheel events should be prepared for
this.

So maybe we could simply use names like wheel-1, wheel-2 (first mouse
wheel), mouse-3, mouse-4 (second mouse wheel), etc.

Or we could have wheel-forward-1, wheel-backward-1, etc.

Or wheel+1, wheel-1, wheel+2, wheel-2, etc.

-- 
Kim F. Storm <storm@cua.dk> http://www.cua.dk