<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Acceleration still too fast with slow and slow-medium finger movements" href="https://bugs.freedesktop.org/show_bug.cgi?id=101139#c26">Comment # 26</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Acceleration still too fast with slow and slow-medium finger movements" href="https://bugs.freedesktop.org/show_bug.cgi?id=101139">bug 101139</a> from <a class="email" href="mailto:peter.hutterer@who-t.net" title="Peter Hutterer <peter.hutterer@who-t.net>"> Peter Hutterer</a> <pre>And here's the thing - libinput's acceleration works in physical distances. So the hw shouldn't really matter because a speed of 10mm/s is always that, regardless of the hardware. As long as touchpad-edge-detector and you agree on the ranges/dimensions on the hardware, there shouldn't be much difference. That acceleration in the attachment is actually a slowdown, we multiply the calculated input speed by a magic constant (0.37) so that a physical delta of 10mm should end up in a delta of 3.7mm [1], give or take with the changing screen resolution. Greg's patch just slows things down even further and a -0.75 should then make this even slower. The question was directed at anyone btw, sorry, should've made that clear. If you have a compositor that doesn't support hidpi, you'd see a slowdown because with twice the pixel density (which libinput knows nothing about) your delta is half as fast - but that's something the compositor has to take care of (mutter already does). It would be good if you could attach an evemu recording from a finger movement. Close your eyes, put your finger down and move from left to right at about 20mm/s - hard to guess I know but it's basically a medium movement. Then I can try to reproduce this here, maybe, hopefully. For reference: here's a video of me moving the finger and the corresponding cursor movement in the libinput debug-gui: <a href="https://photos.app.goo.gl/BTED3UdQwYqw5iW22">https://photos.app.goo.gl/BTED3UdQwYqw5iW22</a> [1] having said that, I'm now wondering what's going on there, because if I move 10mm, it moves by ~10mm on the screen, not 3.7</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>