<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Trackpad cursor movement feels sluggish at very slow speeds and does not move at all when you pivot your finger around a spot" href="https://bugs.freedesktop.org/show_bug.cgi?id=98839#c7">Comment # 7</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Trackpad cursor movement feels sluggish at very slow speeds and does not move at all when you pivot your finger around a spot" href="https://bugs.freedesktop.org/show_bug.cgi?id=98839">bug 98839</a> from <a class="email" href="mailto:peter.hutterer@who-t.net" title="Peter Hutterer <peter.hutterer@who-t.net>"> Peter Hutterer</a> <pre>(In reply to Nate Graham from <a href="show_bug.cgi?id=98839#c5">comment #5</a>) > Touchpad size as listed by the kernel: 117x56mm > User-specified touchpad size: 118x58mm close enough, I'd say > After recompiling libinput and installing it to /, is there an easier way or > reloading the driver than restarting? I'm going to assume you didn't install to / given that you notice an effect but there are a few things to watch out for: use --prefix=/usr and on fedora also add --libdir=/usr/lib64. libinput master has a lower soname than 1.5.3, so you may be installing it correctly but things are still picking up the other one. Make sure to remove libinput.so.10.10.4, as master will currently install 10.10.3 Once installed, you need to restart X only (or the compositor if you're under wayland), no need to actually reboot. For local testing, use the ./tools/event-gui app. It's not exactly the same and affected by lag but good enough to get an idea before having to restart the session. (In reply to Nate Graham from <a href="show_bug.cgi?id=98839#c6">comment #6</a>) > Turning off the hysteresis entirely definitely has an effect, but it doesn't > resolve the issue. > > It doesn't feel like an event rate issue either; with my touchpad, I can > make medium-sized circles as fast as I can move my finger. As I reduce the > size of the circles though, at about 1 cm diameter, the cursor stops moving > in a circle and sort of wobbles awkwardly around its current location. I think what you're seeing is an effect of the firmware skipping data, most likely to avoid pointer wobbles. The problem is simply that the interaction you want to have is very similar to someone holding the finger still but still getting changing sensor readings. This effect is particularly bad on the Lenovo T450 [1] In that case, there isn't much we can do though. [1] <a href="https://who-t.blogspot.com.au/2016/09/libinput-and-lenovo-t450-and-t460.html">https://who-t.blogspot.com.au/2016/09/libinput-and-lenovo-t450-and-t460.html</a> You could try the RMI4 patchset to see if it makes a difference: <a href="http://lkml.iu.edu/hypermail/linux/kernel/1612.2/00646.html">http://lkml.iu.edu/hypermail/linux/kernel/1612.2/00646.html</a></pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>