libinput/doc/svg
Peter Hutterer d6e5313497 filter: improve touchpad acceleration
This seems to give me roughly the same behaviour as macos does on the default
0 speed setting.

* Default speed is lower than before by around 30% [1]
* Acceleration kicks in much sooner (130mm/s vs 250mm/s before)
* Acceleration kicks in slower at lower speeds, so the change from 130mm/s to
  150mm/s is less than that of 320mm/s to 350mm/s
* The effect of the speed setting is a wide-range constant (de|ac)celeration
  [2], which means:
  * The unaccelerated baseline up until the threshold now changes with the
    speed setting
  * The threshold is now the same for all speeds
  * The range of the speed setting should now easily cover all desired device
    speeds.
  * Acceleration is steeper at higher speeds
* Deceleration was left as-is.

[1] This may or may not fix the jumping pointer issues caused by the previous
high defaults. When you have high default acceleration you move the finger
slower. This slow movement caused some touchpads (mostly seen on Lenovos) to
create pointer jumps. These weren't seen on synaptics previously because of a
combination of higher user finger speed (thus not triggering the bug) or just
not being as obvious (2px jump vs 10 px jump).

[2] The speed setting is actually a curve, the closer you get to 1.0 the more
difference you see between two different values. The curve's points are:
-1/0, 0/1, 1/5, so the resolution is closer for slow speeds. We still have
double resolution on the setting though so you'll find what you want.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
2018-05-21 12:18:58 +10:00
..
button-debouncing-wave-diagram.svg evdev: add new debouncing code 2017-11-20 09:55:05 +10:00
button-scrolling.svg doc: move the wiki's scrolling documentation to here 2014-12-23 09:51:37 +10:00
clickfinger-distance.svg touchpad: impose maximum distance limits on clickfingers 2015-06-03 14:43:58 +10:00
clickfinger.svg doc: add illustrations for clickfinger and software button behavior 2015-05-28 11:16:29 +10:00
edge-scrolling.svg Documentation fixes to arrows in svg files 2015-11-09 12:47:40 +10:00
gesture-2fg-ambiguity.svg doc: explain the gesture ambiguity for 2-slot touchpads 2016-01-20 15:38:13 +10:00
palm-detection.svg touchpad: add upper edge into exclusion zone 2017-07-10 09:33:24 +10:00
pinch-gestures-softbuttons.svg gestures: add support for three-finger pinch gestures 2016-01-20 15:38:13 +10:00
pinch-gestures.svg doc: add documentation for touchpad gestures 2015-07-06 14:09:33 +10:00
ptraccel-curve-example.svg Expose a custom acceleration profile 2018-04-26 14:48:37 +10:00
ptraccel-linear.svg doc: update pointer acceleration doc with the fixed graphs 2018-05-11 11:49:39 +10:00
ptraccel-low-dpi.svg doc: add pointer acceleration documentation 2015-08-12 14:06:00 +10:00
ptraccel-touchpad.svg doc: update pointer acceleration doc with the fixed graphs 2018-05-11 11:49:39 +10:00
ptraccel-trackpoint.svg filter: improve touchpad acceleration 2018-05-21 12:18:58 +10:00
software-buttons.svg touchpad: add a middle button software area 2016-04-05 10:13:56 +10:00
swipe-gestures.svg doc: add documentation for touchpad gestures 2015-07-06 14:09:33 +10:00
tablet-axes.svg doc: update tablet svg to show tilt as angle 2016-02-10 15:06:12 +10:00
tablet-cintiq24hd-modes.svg doc: add two svgs showing the modes 2016-06-22 08:48:01 +10:00
tablet-interfaces.svg doc: add a graphic illustrating pad vs tool support 2016-04-18 09:12:02 +10:00
tablet-intuos-modes.svg doc: add two svgs showing the modes 2016-06-22 08:48:01 +10:00
tablet-left-handed.svg doc: add an entry about tablets in left-handed mode 2016-05-09 11:45:01 +10:00
tablet-out-of-bounds.svg test: add tablet test for out-of-bounds motion coordinates 2016-02-11 16:03:13 +10:00
tablet.svg doc: tablet documentation updates 2015-11-18 12:13:54 +10:00
tap-n-drag.svg doc: add a graphic to explain tap-n-drag 2015-06-02 15:47:33 +10:00
thumb-detection.svg touchpad: only try thumb detection in the lowest 15/8mm 2015-07-24 08:50:17 +10:00
top-software-buttons.svg doc: add illustrations for clickfinger and software button behavior 2015-05-28 11:16:29 +10:00
touchscreen-gestures.svg doc: add documentation for touchpad gestures 2015-07-06 14:09:33 +10:00
twofinger-scrolling.svg Documentation fixes to arrows in svg files 2015-11-09 12:47:40 +10:00