@vindex mouse-wheel-tilt-scroll
@vindex mouse-wheel-flip-direction
Emacs can also support horizontal scrolling if your mouse's wheel can
-be tilted, or your touchpad supports it. This feature is off by
-default; the variable @code{mouse-wheel-tilt-scroll} turns it on. If
-you'd like to reverse the direction of horizontal scrolling, customize
-the variable @code{mouse-wheel-flip-direction} to a non-@code{nil}
-value.
+be tilted, or if your touchpad supports it. This feature is off by
+default; the variable @code{mouse-wheel-tilt-scroll} turns it on, if
+you customize it to a non-@code{nil} value. By default, tilting the
+mouse wheel scrolls the window's view horizontally in the direction of
+the tilt: e.g., tilting to the right scrolls the window to the right,
+so that the text displayed in the window moves horizontally to the
+left. If you'd like to reverse the direction of horizontal scrolling,
+customize the variable @code{mouse-wheel-flip-direction} to a
+non-@code{nil} value.
When the mouse pointer is over an image, scrolling the mouse wheel
with the @key{Ctrl} modifier scales the image under the mouse pointer.
;;; For tilt-scroll
;;;
(defcustom mouse-wheel-tilt-scroll nil
- "Enable horizontal scrolling via mouse or touchpad.
+ "Enable horizontal scrolling by tilting mouse wheel or via touchpad.
Also see `mouse-wheel-flip-direction'."
:group 'mouse
:type 'boolean
(defcustom mouse-wheel-flip-direction nil
"Swap direction of `wheel-right' and `wheel-left'.
-This inverts the direction of horizontal scrolling. Also see
-`mouse-wheel-tilt-scroll'."
+By default, `wheel-right' scrolls the text to the right,
+and `wheel-left' scrolls in the other direction.
+If this variable is non-nil, it inverts the direction of
+horizontal scrolling by tilting the mouse wheel.
+Also see `mouse-wheel-tilt-scroll'."
:group 'mouse
:type 'boolean
:version "26.1")