From 802b0e14d0569ac36e9d64a4e0a6f3f8ef47fa0e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jos=C3=A9=20Exp=C3=B3sito?= Date: Mon, 6 Nov 2023 15:19:51 +0100 Subject: [PATCH] doc/user: add FAQ about scroll speed MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This question showed up in my email and it has been asked in the issue tracker a few times. Explaining why libinput is not the right place to implement it for future reference. Signed-off-by: José Expósito --- doc/user/faqs.rst | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/doc/user/faqs.rst b/doc/user/faqs.rst index f7dbc124..88d326c9 100644 --- a/doc/user/faqs.rst +++ b/doc/user/faqs.rst @@ -359,3 +359,20 @@ invoke ``sed``. It will not have any effect on the original ``sed`` instance. The only way to modify libinput's behavior is to use the configuration options exposed by the respective compositor. Those affect the libinput context inside the compositor and thus have an effect on the input device behavior. + +------------------------------------------------------------------------------ +Can I configure scroll speed? +------------------------------------------------------------------------------ + +No, or at least, not as a libinput option. + +When using a mouse, libinput notifies callers about physical scroll wheel +movement. When using another device, libinput notifies scroll in scroll units. + +It is up to the caller to transform those events into a number of pixels to +scroll and, if desired, provide a way to adjust scroll speed. + +This transformation cannot be done in libinput because it may depend on context +only known by the caller. For example, a caller may want to scroll faster +depending on how many pages a document has or depending on the widget that +receives the scroll events.