Re: master e37eb7f: Add support for pixel wheel deltas on NS

[Po Lu <luangruo@yahoo.com>]

Eli Zaretskii <eliz@gnu.org> writes:

> Btw, I have a general question regarding this "pixel-resolution"
> scrolling support:

> With mwheel.el, Emacs users can configure the meaning of each scroll
> event in terms of text lines, via the mouse-wheel-scroll-amount
> variable.  But with this new mode, there's no such user control: the
> conversion of the scroll amount reported by the wheel event to pixels
> is either hard-coded in our code, or (on NS) determined by the OS.
> Does it strike someone as "un-Emacsy"?

It seems OK to me, but we could perhaps have customizations for that.

The problem is that I don't see how such a customization could be
implemented on platforms such as NS, or in the future, the PGTK port.

> Also, if we detect that the mouse wheel is capable of reporting
> fine-resolution scrolls, we use that unconditionally, and users have
> no say about that.  So if a user sets x-coalesce-scroll-events to nil
> manually, but doesn't enable this new mode, they suddenly get much
> faster scrolling because mwheel.el disregards the pixel-wise deltas.
> Right?

Yes, that's correct.

> So maybe we should make x-coalesce-scroll-events and internal
> variable, and say so in its doc string, because it should only be set
> by this mode and its ilk, which do pay attention to the pixel deltas?

I could imagine some user customizations making use of it, but I have no
objection to making it an internal variable.

Thanks.