[PATCH libinput] touchpad: drop distance threshold to detect pinches

[Peter Hutterer]

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 at who-t.net>
---
 src/evdev-mt-touchpad-gestures.c | 17 +----------------
 1 file changed, 1 insertion(+), 16 deletions(-)

diff --git a/src/evdev-mt-touchpad-gestures.c b/src/evdev-mt-touchpad-gestures.c
index 1acf111..2eedb14 100644
--- a/src/evdev-mt-touchpad-gestures.c
+++ b/src/evdev-mt-touchpad-gestures.c
@@ -264,26 +264,11 @@ tp_gesture_twofinger_handle_state_none(struct tp_dispatch *tp, uint64_t time)
 static enum tp_gesture_2fg_state
 tp_gesture_twofinger_handle_state_unknown(struct tp_dispatch *tp, uint64_t time)
 {
-	struct normalized_coords normalized;
-	struct device_float_coords delta;
 	struct tp_touch *first = tp->gesture.touches[0],
 			*second = tp->gesture.touches[1];
 	int dir1, dir2;
 
-	delta = device_delta(first->point, second->point);
-	normalized = tp_normalize_delta(tp, delta);
-
-	/* If fingers are further than 3 cm apart assume pinch */
-	if (normalized_length(normalized) > TP_MM_TO_DPI_NORMALIZED(30)) {
-		tp_gesture_get_pinch_info(tp,
-					  &tp->gesture.initial_distance,
-					  &tp->gesture.angle,
-					  &tp->gesture.center);
-		tp->gesture.prev_scale = 1.0;
-		return GESTURE_2FG_STATE_PINCH;
-	}
-
-	/* Elif fingers have been close together for a while, scroll */
+	/* if fingers have been close together for a while, scroll */
 	if (time > (tp->gesture.initial_time + DEFAULT_GESTURE_2FG_SCROLL_TIMEOUT)) {
 		tp_gesture_set_scroll_buildup(tp);
 		return GESTURE_2FG_STATE_SCROLL;
-- 
2.4.3