rpms/libinput
5
0
Fork 0
Code Issues Pull Requests Releases Activity

Improve responsiveness of touchpads by reducing the motion history.

Browse Source
This commit is contained in:
Peter Hutterer 2016-11-22 10:31:04 +10:00
parent 8644d0574a
commit 41496b9261
2 changed files with 68 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

62
0001-touchpad-only-use-the-last-two-coordinates-for-delta.patch Normal file
View File

@ -0,0 +1,62 @@
From e288c3045d0c582ee19e85cbe11529dc374d4bbf Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Mon, 21 Nov 2016 08:39:47 +1000
Subject: [PATCH libinput] touchpad: only use the last two coordinates for
delta calculation
Taking the last 4 points means factoring in a coordinate that may be more than
40ms in the past - or even more when the finger moves slowly and we don't get
events for a while. This makes the pointer more sluggish and slower to catch up
with what the finger is actually doing.
We already have the motion hysteresis as a separate item to prevent jumps (and
thus adds some delay to the movement), the calculation over time doesn't
provide enough benefit to justify the sluggish pointer.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
---
src/evdev-mt-touchpad.c | 20 +++++---------------
1 file changed, 5 insertions(+), 15 deletions(-)
diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index d72cb19..7b8514c 100644
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -262,29 +262,19 @@ tp_end_sequence(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
tp_end_touch(tp, t, time);
}
-static double
-tp_estimate_delta(int x0, int x1, int x2, int x3)
-{
- return (x0 + x1 - x2 - x3) / 4.0;
-}
-
struct normalized_coords
tp_get_delta(struct tp_touch *t)
{
struct device_float_coords delta;
const struct normalized_coords zero = { 0.0, 0.0 };
- if (t->history.count < TOUCHPAD_MIN_SAMPLES)
+ if (t->history.count <= 1)
return zero;
- delta.x = tp_estimate_delta(tp_motion_history_offset(t, 0)->x,
- tp_motion_history_offset(t, 1)->x,
- tp_motion_history_offset(t, 2)->x,
- tp_motion_history_offset(t, 3)->x);
- delta.y = tp_estimate_delta(tp_motion_history_offset(t, 0)->y,
- tp_motion_history_offset(t, 1)->y,
- tp_motion_history_offset(t, 2)->y,
- tp_motion_history_offset(t, 3)->y);
+ delta.x = tp_motion_history_offset(t, 0)->x -
+ tp_motion_history_offset(t, 1)->x;
+ delta.y = tp_motion_history_offset(t, 0)->y -
+ tp_motion_history_offset(t, 1)->y;
return tp_normalize_delta(t->tp, delta);
}
--
2.9.3

7
libinput.spec
View File

@ -5,7 +5,7 @@
Name: libinput
Version: 1.5.1
Release: 1%{?gitdate:.%{gitdate}git%{gitversion}}%{?dist}
Release: 2%{?gitdate:.%{gitdate}git%{gitversion}}%{?dist}
Summary: Input device library
License: MIT
@ -18,6 +18,8 @@ Source2: commitid
Source0: http://www.freedesktop.org/software/libinput/libinput-%{version}.tar.xz
%endif
Patch01: 0001-touchpad-only-use-the-last-two-coordinates-for-delta.patch
BuildRequires: git
BuildRequires: autoconf automake libtool pkgconfig
BuildRequires: libevdev-devel
@ -94,6 +96,9 @@ find $RPM_BUILD_ROOT -name '*.la' -delete
%changelog
* Tue Nov 22 2016 Peter Hutterer <peter.hutterer@redhat.com> 1.5.1-2
- Improve responsiveness of touchpads by reducing the motion history.
* Fri Nov 11 2016 Peter Hutterer <peter.hutterer@redhat.com> 1.5.1-1
- libinput 1.5.1