[PATCH libinput 11/11] touchpad: put a movement threshold on thumb detection

[Hans de Goede]

Hi,

On 22-07-15 07:09, Peter Hutterer wrote:
> If a thumb moves around, it's not resting and we should consider it a normal
> touch.
>
> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> ---
>   src/evdev-mt-touchpad.c | 16 ++++++++++++++++
>   src/evdev-mt-touchpad.h |  1 +
>   test/touchpad.c         | 31 ++++++++++++++++++++++++++++---
>   3 files changed, 45 insertions(+), 3 deletions(-)
>
> diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
> index 0b39bf6..63ce488 100644
> --- a/src/evdev-mt-touchpad.c
> +++ b/src/evdev-mt-touchpad.c
> @@ -636,6 +636,22 @@ tp_thumb_detect(struct tp_dispatch *tp, struct tp_touch *t, uint64_t time)
>   		goto out;
>   	}
>
> +	/* If the thumb moves by more than 7mm, it's not a resting thumb */
> +	if (t->state == TOUCH_BEGIN)
> +		t->thumb.initial = t->point;
> +	else if (t->state == TOUCH_UPDATE) {
> +		struct device_float_coords delta;
> +		struct normalized_coords normalized;
> +
> +		delta = device_delta(t->point, t->thumb.initial);
> +		normalized = tp_normalize_delta(tp, delta);
> +		if (normalized_length(normalized) >
> +			TP_MM_TO_DPI_NORMALIZED(7)) {
> +			t->thumb.state = THUMB_STATE_NO;
> +			goto out;
> +		}
> +	}
> +
>   	/* Note: a thumb at the edge of the touchpad won't trigger the
>   	 * threshold, the surface area is usually too small. So we have a
>   	 * two-stage detection: pressure and time within the area.

If you want this to mark thouches with THUMB_STATE_YES as THUMB_STATE_NO
this needs to be above the:

     /* once a thumb, always a thumb, once ruled out always ruled out */
     if (!tp->thumb.detect_thumbs ||
         t->thumb.state != THUMB_STATE_MAYBE)
          return;

Block, and maybe the commentline above the if() of that block needs to
be updated too ...

Also does this commit not require updates to the svg with the thumb detect
statemachine ?

Regards,

Hans



> diff --git a/src/evdev-mt-touchpad.h b/src/evdev-mt-touchpad.h
> index 89801d6..0dfc6ac 100644
> --- a/src/evdev-mt-touchpad.h
> +++ b/src/evdev-mt-touchpad.h
> @@ -204,6 +204,7 @@ struct tp_touch {
>   	struct {
>   		enum tp_thumb_state state;
>   		uint64_t first_touch_time;
> +		struct device_coords initial;
>   	} thumb;
>   };
>
> diff --git a/test/touchpad.c b/test/touchpad.c
> index 875bc58..25db43f 100644
> --- a/test/touchpad.c
> +++ b/test/touchpad.c
> @@ -4054,15 +4054,39 @@ START_TEST(touchpad_thumb_update_no_motion)
>
>   	litest_drain_events(li);
>
> +	litest_touch_down(dev, 0, 59, 99);
> +	litest_touch_move_extended(dev, 0, 59, 99, axes);
> +	litest_touch_move_to(dev, 0, 60, 99, 80, 99, 10, 0);
> +	litest_touch_up(dev, 0);
> +
> +	litest_assert_empty_queue(li);
> +}
> +END_TEST
> +
> +START_TEST(touchpad_thumb_moving)
> +{
> +	struct litest_device *dev = litest_current_device();
> +	struct libinput *li = dev->libinput;
> +	struct axis_replacement axes[] = {
> +		{ ABS_MT_PRESSURE, 190 },
> +		{ -1, 0 }
> +	};
> +
> +	litest_disable_tap(dev->libinput_device);
> +	enable_clickfinger(dev);
> +
> +	if (!has_thumb_detect(dev))
> +		return;
> +
> +	litest_drain_events(li);
> +
>   	litest_touch_down(dev, 0, 50, 99);
>   	litest_touch_move_to(dev, 0, 50, 99, 60, 99, 10, 0);
> -	litest_assert_only_typed_events(li, LIBINPUT_EVENT_POINTER_MOTION);
> -
>   	litest_touch_move_extended(dev, 0, 65, 99, axes);
>   	litest_touch_move_to(dev, 0, 65, 99, 80, 99, 10, 0);
>   	litest_touch_up(dev, 0);
>
> -	litest_assert_empty_queue(li);
> +	litest_assert_only_typed_events(li, LIBINPUT_EVENT_POINTER_MOTION);
>   }
>   END_TEST
>
> @@ -4520,6 +4544,7 @@ litest_setup_tests(void)
>
>   	litest_add("touchpad:thumb", touchpad_thumb_begin_no_motion, LITEST_CLICKPAD, LITEST_ANY);
>   	litest_add("touchpad:thumb", touchpad_thumb_update_no_motion, LITEST_CLICKPAD, LITEST_ANY);
> +	litest_add("touchpad:thumb", touchpad_thumb_moving, LITEST_CLICKPAD, LITEST_ANY);
>   	litest_add("touchpad:thumb", touchpad_thumb_clickfinger, LITEST_CLICKPAD, LITEST_ANY);
>   	litest_add("touchpad:thumb", touchpad_thumb_btnarea, LITEST_CLICKPAD, LITEST_ANY);
>   	litest_add("touchpad:thumb", touchpad_thumb_edgescroll, LITEST_CLICKPAD, LITEST_ANY);
>