This makes two-finger scrolling in straight lines easier, while still
allowing free/diagonal movement. It works in three stages:
1) Initial movement
- For the first few millimeters, scroll movements within 30 degrees
of horizontal or vertical are straightened to 90-degree angles.
- Scroll movements close to 45 degree diagonals are unchanged.
- If movement continues very close to straight horizontal or
vertical, stage 2 begins and the axis lock engages.
- If movement continues along a diagonal, stage 2 is skipped and
free scrolling is immediately enabled.
2) Axis lock
- If the user scrolls fairly closely to straight vertical, no
horizontal movement will happen at all, and vice versa.
- It is possible to switch between straight vertical and straight
horizontal, and the axis lock will automatically change.
- If deliberate diagonal movement is detected at any point, stage
3 begins and the axis lock disengages.
3) Free scrolling
- Scrolling is unconstrained until the fingers are lifted.
Two fingers on the touchpad, they're 40x40mm apart, that's a pinch. But only
after a timeout because we don't want to start a 2fg gesture if the user puts
down the third/fourth finger within the next few ms.
Related to: https://bugs.freedesktop.org/show_bug.cgi?id=99830
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Previously, touchpad deltas were converted to 1000-dpi normalized coordinates
and handled from there. This changed in bdd4264d61 (1.6)
when the filter functions started taking device coordinates instead. Since
then, we used to convert the device delta to normalized coordinates, then
(often immediately) convert back to device coordinates, albeit for equal x/y
resolution. This isn't necessary, we can just convert the device coordinates
to x/y-equal resolution device coordinates and pass those on.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
We don't know the position of the third finger on 2-slot touchpads, differing
between swipe and pinch is reliable. Simply disable 3-finger pinch and always
use swipe; 3fg pinch is uncommon anyway and it's better to have one of the
gestures working reliably than both unreliably.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Instead of reimplementing a for loop every time.
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Prefix device log messages with the device's sysname so it's more obvious
where the messages are coming from. This makes it much easier to grep for a
specific device's messages but also adds some identifier to messages that
were previously without any identifier (e.g. all the state machine debugging)
All info and error messages also automatically prefix the device name, so
those messages are standardised too, e.g
an info message now:
event4 - SynPS/2 Synaptics TouchPad: is tagged by udev as: Touchpad
a debug message now:
event4 - using pressure-based touch detection
And since this required changing a lot of the strings in messages anyway,
polish a few minor things too.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Now that the acceleration code doesn't use dpi-normalized coordinates anymore,
we don't need to use them in the touchpad code. Switch to physical distances
instead, it makes debugging a lot saner.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
If the fingers rest on the touchpad without moving for a timeout, switch to
pinch or swipe based on the finger position. We already switched to two-finger
scrolling based on the timeout, now we also do so for 3 and 4 finger gestures.
This gives us better reaction to small movements.
This also fixes previously unreachable code: the test for the finger position
required at least 3 fingers down but was within a condition that ensured only
2 fingers were down. This was introduced in 11917061fe.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
This timeout is there to switch to scrolling when the fingers rest on the
touchpad unmoving and thus avoids the initial scroll threshold for slow
scrolls.
Since the only other gestures we support are swipe (usually a fast movement)
and pinch-and-rotate (also a fast movement) we can drop the timeout down
significantly and thus make the scroll feel more reactive.
https://bugs.freedesktop.org/show_bug.cgi?id=93504
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
These are internal functions, if we need them to return an error code we can
change that at any time. Meanwhile, if we only ever return 0 anyway we might
as well just make them voids to save on error paths.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Yong Bakos <ybakos@humanoriented.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Increase the mm move threshold for 3 and 4 finger gestures to 2 and 3 mm,
respectively. In multi-finger gestures it's common to have minor movement
while all fingers are being put down or before the conscious movement starts.
This can trigger invalid gesture detection (e.g. a pinch instead of a swipe).
Increase the movement threshold to make sure we have sufficient input data.
No changes to 2-finger movements.
https://bugs.freedesktop.org/show_bug.cgi?id=96687
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
A natural hand position for a 4-finger swipe will have one finger well below
the other triggering the pinch detection. This is obviously wrong, only do the
finger position analysis when we have 2 fingers.
This is only a partial fix, for 3-4 finger gestures chances are high that the
third/fourth finger come in a different event frame. Before that we likely
detect 2 fingers in a possible pinch position and still trigger the code path.
This issue has to be fixed separately.
https://bugs.freedesktop.org/show_bug.cgi?id=96687
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Introduced in 6ad303b as part of an code flow optimization, causing any 3+
finger gesture to be posted as swipe gesture, even when gestures are disabled.
However, the event is filtered in the higher levels with a bug message printed
to the log.
Don't post swipe gestures for devices where gestures are disabled.
https://bugs.freedesktop.org/show_bug.cgi?id=95314
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Because our delta calculation factors in previous events on touchpads (to
reduce jitter) we may get a nonzero delta if we have an event that doesn't
actually change x or y.
Drop the t->dirty workaround introduced in a608d9d, an event that virtually
disappears can mess up our state machines.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
If the fingers are vertically apart by more than 20mm we used to assume a
pinch gesture immediately. This is too close together for some users during
two-finger scrolling. Since we should always bias towards scrolling, only
trigger this detection for three fingers, the rest has to go through the
movement detection.
The reason for the pinch detection here was to differentiate from 3fg swipe
gestures (83f3dbd1), hence we're still in spirit of that patch.
https://bugs.freedesktop.org/show_bug.cgi?id=94264
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Tested-by: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
When two fingers move slowly, an event frame may only have one finger motion,
followed by a frame with the other finger's motion. If we only divide by the
number of dirty touches, the speed of the gesture increases whenever that
happens.
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
The first/second variables are only needed for pinch, so we can skip them
here.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
No point trying to detect pinch gestures if we only have one set of
coordinates. This makes two-finger scrolling on ST touchpads more reactive.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Synaptics, Elantech and Alps semi-mt devices all have issues with reporting
correct MT data, even the bounding box which semi-mt devices are supposed to
report is wrong.
Synaptics devices have massive jumps with two fingers down. Elantech devices
may open slots without coordinate data. Alps devices may send 0/0 coordinates
as initial slot position.
All these may be addressable with specific quirks, but the actual benefit is
largely restricted to better palm detection (though even with quirks this is
unlikely to work) and support for pinch gestures (again, lack of coordinates
makes supporting those hard anyway).
Elantech: https://bugs.freedesktop.org/show_bug.cgi?id=93583
Alps: https://bugzilla.redhat.com/show_bug.cgi?id=1295073
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Pure movement detection is quite unreliable when trying 3-finger pinch
gestures, and many gestures are misdetected as swipes. Before looking at the
motion, look at the constellation of the fingers. If one finger is 20mm below
the other one, assume they're in a pinch position.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
At least on the t440, this is enough to trigger correct detection between
pinch and scroll 90% of the time. Since scrolling is significantly more
prevalent than gesturing, erring on the side of scrolling at the cost of
misdetecting some gestures is acceptable.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
For short and quick scroll gestures, those that should only trigger a few
lines of scroll the pointer acceleration is wildly unpredictable. Since we
average the motion of both fingers it's hard enough to intuitively predict
what the motion will be like. On top of that is the small threshold before we
start scrolling, so some of the initial motion gets swallowed before we
accelerate, making the next motion even more unpredictable.
The end result is that multiple seemingly identical finger motions cause
wildly different scroll motion.
Drop pointer acceleration for two-finger and edge scrolling. This makes short
scroll motions much more predictable and doesn't seem to have much effect on
long scroll motions. Plus, in natural scroll mode it really feels like the
content is stuck to your fingers now. Go wash your hands.
https://bugzilla.redhat.com/show_bug.cgi?id=1249365
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Holding the fingers in place without moving for 500ms is long enough to lock
in a scroll gesture, especially while we're still waiting for the rest of the
stack to expose pinch gestures.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Unlike ALPS and Synaptics semi-mt touchpads, the Elantech touchpads appear to
be precise enough to allow a smaller motion threshold before we decide on the
type of gesture (pinch vs scroll).
https://bugs.freedesktop.org/show_bug.cgi?id=91475
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Follow-up to eb146677e, if we disable 2fg scrolling on those touchpads we
should also disable gestures. The data doesn't magically become more useful.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Not all multi-finger touchpads are able to reliably produce gestures, so make
it optional. This patch just adds a boolean (currently always true) that gets
set on touchpad init time, i.e. it is not run-time configurable.
Three and four-finger gestures are filtered out in gesture_notify(), if the
cap isn't set the event is discarded.
For two-finger gestures we prevent a transition to PINCH, so we don't
inadvertently detect a pinch gesture and then not send events. This way, a 2fg
gesture is always scroll.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
This gives us too many false positives of 2fg scroll being detected as pinch
gesture. Reporter in [1] uses index+ring finger and thus exceeds the distance
easily (that's admittedly a special case).
This is worsed by the lack of a client stack that handles the gestures. User's
don't see that they're inadvertently performing a gesture, they just see 2fg
scroll not working.
Drop the distance for now, once we have a ubiquitous client stack we can
revisit and bring it back.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1246868
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
We need to check fake fingers as well as real fingers, especially for
two-finger scrolling on single-touch touchpads with BTN_TOOL_DOUBLETAP.
https://bugzilla.redhat.com/show_bug.cgi?id=1246651
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
In order to provide higher precision event time stamps, change the
internal time measuring from milliseconds to microseconds.
Microseconds are chosen because it is the most fine grained time stamp
we can get from evdev.
The API is extended with high precision getters whenever the given
information is available.
Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
3mm is too large, especially on fine-grained scroll motions. Since we
already use the hysteresis to defuzz the current touchpad point, having a
slower threshold here should not cause any adverse motions.
This affects the pinch gestures too and needs a minor test adjustment. The
atmel hover device's resolution is low enough that we trigger a >1 degree
angle now, make the movement a bit more finegrained.
https://bugs.freedesktop.org/show_bug.cgi?id=91364
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Thumb detection interfered with gestures a fair bit but it shouldn't. A pinch
gesture with a thumb is a fairly natural move so we shouldn't cancel that.
A swipe gesture with a thumb on the touchpad - well, don't do that. No need
for code here.
Reported-by: Carlos Garnacho <carlosg@gnome.org>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Carlos Garnacho <carlosg@gnome.org>
All touchpad recordings seen so far show that a value above 100 is definitely
a thumb or a palm. Values below are harder to discern, and the same isn't true
for touchpads supporting ABS_PRESSURE instead of ABS_MT_PRESSURE.
The handling of a touch is as outlined in tp_thumb_detect:
* thumbs are ignored for pointer motion
* thumbs cancel gestures
* thumbs are ignored for clickfinger count
* edge scrolling doesn't care either way
* software buttons don't care either way
* tap: only if thumb on begin
The handling of thumbs while tapping is the simplest approach only, more to
come in follow-up patches.
Note that "thumb" is the synonym for "this touch is too big to be a
fingertip". Which means that a light thumb touch will still be counted as a
finger. The side-effect here is that thumbs resting a the bottom edge of the
touchpad will almost certainly not trigger the pressure threshold because
most of the thumb is off the touchpad.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
