<html>
<head>
<base href="https://bugs.freedesktop.org/">
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - libinput-1.10.3: two-finger-scrolling snaps back when lifting fingers"
href="https://bugs.freedesktop.org/show_bug.cgi?id=105727">105727</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>libinput-1.10.3: two-finger-scrolling snaps back when lifting fingers
</td>
</tr>
<tr>
<th>Product</th>
<td>Wayland
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
<tr>
<th>Hardware</th>
<td>Other
</td>
</tr>
<tr>
<th>OS</th>
<td>All
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>medium
</td>
</tr>
<tr>
<th>Component</th>
<td>libinput
</td>
</tr>
<tr>
<th>Assignee</th>
<td>wayland-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>main.haarp@gmail.com
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=138333" name="attach_138333" title="evemu log showing behavior">attachment 138333</a> <a href="attachment.cgi?id=138333&action=edit" title="evemu log showing behavior">[details]</a></span>
evemu log showing behavior
Hello.
I'm currently using libinput 1.10.3 with a SynPS/2 Synaptics TouchPad on a
Thinkpad W530. A recent update of libinput, I think either 1.10.2 or 1.10.3
introduced uncomfortable scrolling behavior.
When two-finger-scrolling, very often the scroll operation "snaps back" when I
lift my fingers. By that I mean a scroll event in the opposite direction is
generated.
Here's a debug-events example:
event12 POINTER_AXIS +4.64s vert 2.52* horiz 0.25* (finger)
event12 POINTER_AXIS +4.67s vert 6.83* horiz 0.25* (finger)
....
event12 POINTER_AXIS +5.16s vert 0.36* horiz 0.00 (finger)
event12 POINTER_AXIS +5.24s vert 0.18* horiz -0.25* (finger)
** lifting fingers around now **
event12 POINTER_AXIS +5.36s vert 0.18* horiz -0.25* (finger)
event12 POINTER_AXIS +5.41s vert -13.31* horiz -20.35* (finger)
event12 POINTER_AXIS +5.42s vert 0.00* horiz 0.00* (finger)
The negative vert and horiz event is obvious.
I am also attaching an evemu log that shows how I scroll. It contains three
attempts, the first and third exhibited a snap-back, the second one did not.
It seems I can avoid snap-back by first lifting one finger and then the other.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are the assignee for the bug.</li>
</ul>
</body>
</html>