xf86-input-libinput: Changes to 'master'

[GitLab Mirror]

 include/libinput-properties.h |    6 ++
 man/libinput.man              |   25 +++++++++
 src/xf86libinput.c            |  112 +++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 141 insertions(+), 2 deletions(-)

New commits:
commit 9bb9e635df731eea1ad7022d1f188ace9802b353
Author: Peter Hutterer <peter.hutterer at who-t.net>
Date:   Tue Apr 13 16:07:24 2021 +1000

    Implement a touchpad scroll distance property
    
    To be used for touchpads and continuous (i.e. button-based scrolling).
    
    libinput provides us with pixel data for finger-based and button-based
    scrolling but the X server does support this - XI2.1 smooth scrolling is
    merely centered around a logical scroll click (defined as "increment"), with
    smooth scrolling being a fraction of that increment. For example, in the old
    synaptics driver that value was in device-specific units and thus different
    for every device.
    
    The increment is a constant value set in the ScrollClass and cannot be changed
    at device runtime. So we simply initialize with a random default (15, because
    that works well for wheels) and then scale our pixel delta in to that range.
    
    With the default value, a 15 pixel movement would result in a logical scroll
    click, if the distance is set to 30 the users has to move 30 pixels to trigger
    that scroll click. Pixel here being defined as the deltas that libinput
    provides to us.
    
    From the client's perspective nothing changes, the increment is still the
    same.
    
    Range checks are quite restrictive, this option is supposed to improve
    usability, not as a workaround around other bugs.
    
    Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>