[PATCH libinput] evdev: split scroll threshold and direction lock threshold into two

[Peter Hutterer]

The previous code used a 5mm threshold before axis events were posted. This
threshold was on top of the 2mm 2fg threshold (and timeout handling) in the
gesture code and effectively prevented events from being sent after a timeout,
or in the 2mm-5mm range.

We still want a directional lock though, so split the two out. The default 5mm
threshold is set to 0 for touchpads since we have our own handling of the
threshold there. The directional lock only applies once scrollin has started
and remains on 5mm.

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
 src/evdev-mt-touchpad.c | 5 +++--
 src/evdev.c             | 5 +++--
 src/evdev.h             | 1 +
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index a683d9a..872da98 100644
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -1628,8 +1628,9 @@ tp_init_scroll(struct tp_dispatch *tp, struct evdev_device *device)
 	tp->scroll.method = tp_scroll_get_default_method(tp);
 	tp->device->base.config.scroll_method = &tp->scroll.config_method;
 
-	/* In mm for touchpads with valid resolution, see tp_init_accel() */
-	tp->device->scroll.threshold = 5.0;
+	 /* In mm for touchpads with valid resolution, see tp_init_accel() */
+	tp->device->scroll.threshold = 0.0;
+	tp->device->scroll.direction_lock_threshold = 5.0;
 
 	return 0;
 }
diff --git a/src/evdev.c b/src/evdev.c
index 17c2604..53ebf9d 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -2146,6 +2146,7 @@ evdev_device_create(struct libinput_seat *seat,
 	device->pending_event = EVDEV_NONE;
 	device->devname = libevdev_get_name(device->evdev);
 	device->scroll.threshold = 5.0; /* Default may be overridden */
+	device->scroll.direction_lock_threshold = 5.0; /* Default may be overridden */
 	device->scroll.direction = 0;
 	device->scroll.wheel_click_angle =
 		evdev_read_wheel_click_prop(device);
@@ -2414,12 +2415,12 @@ evdev_post_scroll(struct evdev_device *device,
 	   trigger speed to start scrolling in the other direction */
 	} else if (!evdev_is_scrolling(device,
 			       LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL)) {
-		if (fabs(delta->y) >= device->scroll.threshold)
+		if (fabs(delta->y) >= device->scroll.direction_lock_threshold)
 			evdev_start_scrolling(device,
 				      LIBINPUT_POINTER_AXIS_SCROLL_VERTICAL);
 	} else if (!evdev_is_scrolling(device,
 				LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL)) {
-		if (fabs(delta->x) >= device->scroll.threshold)
+		if (fabs(delta->x) >= device->scroll.direction_lock_threshold)
 			evdev_start_scrolling(device,
 				      LIBINPUT_POINTER_AXIS_SCROLL_HORIZONTAL);
 	}
diff --git a/src/evdev.h b/src/evdev.h
index be5df0d..65c5a41 100644
--- a/src/evdev.h
+++ b/src/evdev.h
@@ -166,6 +166,7 @@ struct evdev_device {
 		void (*change_scroll_method)(struct evdev_device *device);
 		bool button_scroll_active;
 		double threshold;
+		double direction_lock_threshold;
 		uint32_t direction;
 		struct normalized_coords buildup;
 
-- 
2.4.3