[PATCH libinput] Introduce non-accelerated motion event vectors

Jonas Ådahl jadahl at gmail.com
Tue Dec 2 05:44:16 PST 2014


For certain applications (such as FPS games) it is necessary to use
non-accelerated motion events (the motion vector that is passed to the
acceleration filter) to get a more natural feeling. Supply this
information by passing both accelerated and non-accelerated motion
vectors to the existing motion event.

Note that the non-accelerated motion event is not equivalent to 'raw'
events as read from devices.

Signed-off-by: Jonas Ådahl <jadahl at gmail.com>
---
 src/evdev-mt-touchpad-edge-scroll.c |  2 +-
 src/evdev-mt-touchpad.c             | 20 ++++++++++----
 src/evdev-mt-touchpad.h             |  4 ++-
 src/evdev.c                         | 19 ++++++++++----
 src/libinput-private.h              |  4 ++-
 src/libinput.c                      | 20 +++++++++++++-
 src/libinput.h                      | 30 +++++++++++++++++++++
 test/pointer.c                      | 52 +++++++++++++++++++++++++++++++++++++
 8 files changed, 137 insertions(+), 14 deletions(-)

diff --git a/src/evdev-mt-touchpad-edge-scroll.c b/src/evdev-mt-touchpad-edge-scroll.c
index 1dca0ea..d68fc68 100644
--- a/src/evdev-mt-touchpad-edge-scroll.c
+++ b/src/evdev-mt-touchpad-edge-scroll.c
@@ -338,7 +338,7 @@ tp_edge_scroll_post_events(struct tp_dispatch *tp, uint64_t time)
 		}
 
 		tp_get_delta(t, &dx, &dy);
-		tp_filter_motion(tp, &dx, &dy, time);
+		tp_filter_motion(tp, &dx, &dy, NULL, NULL, time);
 
 		if (fabs(*delta) < t->scroll.threshold)
 			continue;
diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index 8f76ddb..ff76fe2 100644
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -58,13 +58,20 @@ tp_motion_history_offset(struct tp_touch *t, int offset)
 
 void
 tp_filter_motion(struct tp_dispatch *tp,
-	         double *dx, double *dy, uint64_t time)
+	         double *dx, double *dy,
+	         double *dx_noaccel, double *dy_noaccel,
+		 uint64_t time)
 {
 	struct motion_params motion;
 
 	motion.dx = *dx * tp->accel.x_scale_coeff;
 	motion.dy = *dy * tp->accel.y_scale_coeff;
 
+	if (dx_noaccel)
+		*dx_noaccel = motion.dx;
+	if (dy_noaccel)
+		*dy_noaccel = motion.dy;
+
 	if (motion.dx != 0.0 || motion.dy != 0.0)
 		filter_dispatch(tp->device->pointer.filter, &motion, tp, time);
 
@@ -426,7 +433,7 @@ tp_post_twofinger_scroll(struct tp_dispatch *tp, uint64_t time)
 	dx /= nchanged;
 	dy /= nchanged;
 
-	tp_filter_motion(tp, &dx, &dy, time);
+	tp_filter_motion(tp, &dx, &dy, NULL, NULL, time);
 
 	evdev_post_scroll(tp->device, time, dx, dy);
 }
@@ -586,6 +593,7 @@ tp_post_events(struct tp_dispatch *tp, uint64_t time)
 	struct tp_touch *t = tp_current_touch(tp);
 	double dx, dy;
 	int filter_motion = 0;
+	double dx_noaccel, dy_noaccel;
 
 	/* Only post (top) button events while suspended */
 	if (tp->device->suspended) {
@@ -617,10 +625,12 @@ tp_post_events(struct tp_dispatch *tp, uint64_t time)
 		return;
 
 	tp_get_delta(t, &dx, &dy);
-	tp_filter_motion(tp, &dx, &dy, time);
+	tp_filter_motion(tp, &dx, &dy, &dx_noaccel, &dy_noaccel, time);
 
-	if (dx != 0.0 || dy != 0.0)
-		pointer_notify_motion(&tp->device->base, time, dx, dy);
+	if (dx != 0.0 || dy != 0.0 || dx_noaccel != 0.0 || dy_noaccel != 0.0) {
+		pointer_notify_motion(&tp->device->base, time,
+				      dx, dy, dx_noaccel, dy_noaccel);
+	}
 }
 
 static void
diff --git a/src/evdev-mt-touchpad.h b/src/evdev-mt-touchpad.h
index b2603b4..ea77062 100644
--- a/src/evdev-mt-touchpad.h
+++ b/src/evdev-mt-touchpad.h
@@ -276,7 +276,9 @@ tp_set_pointer(struct tp_dispatch *tp, struct tp_touch *t);
 
 void
 tp_filter_motion(struct tp_dispatch *tp,
-	         double *dx, double *dy, uint64_t time);
+	         double *dx, double *dy,
+	         double *dx_noaccel, double *dy_noaccel,
+		 uint64_t time);
 
 int
 tp_tap_handle_state(struct tp_dispatch *tp, uint64_t time);
diff --git a/src/evdev.c b/src/evdev.c
index 908a8ba..f7d88c4 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -198,6 +198,7 @@ evdev_flush_pending_event(struct evdev_device *device, uint64_t time)
 {
 	struct libinput *libinput = device->base.seat->libinput;
 	struct motion_params motion;
+	double dx_noaccel, dy_noaccel;
 	int32_t cx, cy;
 	int32_t x, y;
 	int slot;
@@ -211,8 +212,10 @@ evdev_flush_pending_event(struct evdev_device *device, uint64_t time)
 	case EVDEV_NONE:
 		return;
 	case EVDEV_RELATIVE_MOTION:
-		motion.dx = device->rel.dx / ((double)device->dpi / DEFAULT_MOUSE_DPI);
-		motion.dy = device->rel.dy / ((double)device->dpi / DEFAULT_MOUSE_DPI);
+		dx_noaccel = device->rel.dx / ((double) device->dpi /
+					       DEFAULT_MOUSE_DPI);
+		dy_noaccel = device->rel.dy / ((double) device->dpi /
+					       DEFAULT_MOUSE_DPI);
 		device->rel.dx = 0;
 		device->rel.dy = 0;
 
@@ -221,17 +224,23 @@ evdev_flush_pending_event(struct evdev_device *device, uint64_t time)
 		    hw_is_key_down(device, device->scroll.button)) {
 			if (device->scroll.button_scroll_active)
 				evdev_post_scroll(device, time,
-						  motion.dx, motion.dy);
+						  dx_noaccel, dx_noaccel);
 			break;
 		}
 
 		/* Apply pointer acceleration. */
+		motion.dx = dx_noaccel;
+		motion.dy = dy_noaccel;
 		filter_dispatch(device->pointer.filter, &motion, device, time);
 
-		if (motion.dx == 0.0 && motion.dy == 0.0)
+		if (motion.dx == 0.0 && motion.dy == 0.0 &&
+		    dx_noaccel == 0.0 && dy_noaccel == 0.0) {
 			break;
+		}
 
-		pointer_notify_motion(base, time, motion.dx, motion.dy);
+		pointer_notify_motion(base, time,
+				      motion.dx, motion.dy,
+				      dx_noaccel, dy_noaccel);
 		break;
 	case EVDEV_ABSOLUTE_MT_DOWN:
 		if (!(device->seat_caps & EVDEV_DEVICE_TOUCH))
diff --git a/src/libinput-private.h b/src/libinput-private.h
index 4a9bd54..b36dc95 100644
--- a/src/libinput-private.h
+++ b/src/libinput-private.h
@@ -259,7 +259,9 @@ void
 pointer_notify_motion(struct libinput_device *device,
 		      uint64_t time,
 		      double dx,
-		      double dy);
+		      double dy,
+		      double dx_noaccel,
+		      double dy_noaccel);
 
 void
 pointer_notify_motion_absolute(struct libinput_device *device,
diff --git a/src/libinput.c b/src/libinput.c
index c318eee..f179de8 100644
--- a/src/libinput.c
+++ b/src/libinput.c
@@ -59,6 +59,8 @@ struct libinput_event_pointer {
 	uint32_t time;
 	double x;
 	double y;
+	double dx_noaccel;
+	double dy_noaccel;
 	uint32_t button;
 	uint32_t seat_button_count;
 	enum libinput_button_state state;
@@ -304,6 +306,18 @@ libinput_event_pointer_get_dy(struct libinput_event_pointer *event)
 }
 
 LIBINPUT_EXPORT double
+libinput_event_pointer_get_dx_noaccel(struct libinput_event_pointer *event)
+{
+	return event->dx_noaccel;
+}
+
+LIBINPUT_EXPORT double
+libinput_event_pointer_get_dy_noaccel(struct libinput_event_pointer *event)
+{
+	return event->dy_noaccel;
+}
+
+LIBINPUT_EXPORT double
 libinput_event_pointer_get_absolute_x(struct libinput_event_pointer *event)
 {
 	struct evdev_device *device =
@@ -885,7 +899,9 @@ void
 pointer_notify_motion(struct libinput_device *device,
 		      uint64_t time,
 		      double dx,
-		      double dy)
+		      double dy,
+		      double dx_noaccel,
+		      double dy_noaccel)
 {
 	struct libinput_event_pointer *motion_event;
 
@@ -897,6 +913,8 @@ pointer_notify_motion(struct libinput_device *device,
 		.time = time,
 		.x = dx,
 		.y = dy,
+		.dx_noaccel = dx_noaccel,
+		.dy_noaccel = dy_noaccel,
 	};
 
 	post_device_event(device, time,
diff --git a/src/libinput.h b/src/libinput.h
index 26d94ff..08fef8c 100644
--- a/src/libinput.h
+++ b/src/libinput.h
@@ -497,6 +497,36 @@ libinput_event_pointer_get_dy(struct libinput_event_pointer *event);
 /**
  * @ingroup event_pointer
  *
+ * Return the relative delta of the non-accelerated motion vector of the
+ * current event. For pointer events that are not of type
+ * LIBINPUT_EVENT_POINTER_MOTION, this function returns 0.
+ *
+ * @note It is an application bug to call this function for events other than
+ * LIBINPUT_EVENT_POINTER_MOTION.
+ *
+ * @return the non-accelerated relative x movement since the last event
+ */
+double
+libinput_event_pointer_get_dx_noaccel(struct libinput_event_pointer *event);
+
+/**
+ * @ingroup event_pointer
+ *
+ * Return the relative delta of the non-accelerated motion vector of the
+ * current event. For pointer events that are not of type
+ * LIBINPUT_EVENT_POINTER_MOTION, this function returns 0.
+ *
+ * @note It is an application bug to call this function for events other than
+ * LIBINPUT_EVENT_POINTER_MOTION.
+ *
+ * @return the non-accelerated relative y movement since the last event
+ */
+double
+libinput_event_pointer_get_dy_noaccel(struct libinput_event_pointer *event);
+
+/**
+ * @ingroup event_pointer
+ *
  * Return the current absolute x coordinate of the pointer event, in mm from
  * the top left corner of the device. To get the corresponding output screen
  * coordinate, use libinput_event_pointer_get_absolute_x_transformed().
diff --git a/test/pointer.c b/test/pointer.c
index 206accd..9de414c 100644
--- a/test/pointer.c
+++ b/test/pointer.c
@@ -140,6 +140,57 @@ START_TEST(pointer_motion_absolute)
 END_TEST
 
 static void
+test_noaccel_event(struct litest_device *dev, int dx, int dy)
+{
+      struct libinput *li = dev->libinput;
+      struct libinput_event *event;
+      struct libinput_event_pointer *ptrev;
+      double ev_dx, ev_dy;
+
+      litest_event(dev, EV_REL, REL_X, dx);
+      litest_event(dev, EV_REL, REL_Y, dy);
+      litest_event(dev, EV_SYN, SYN_REPORT, 0);
+
+      libinput_dispatch(li);
+
+      event = libinput_get_event(li);
+      ck_assert(event != NULL);
+      ck_assert_int_eq(libinput_event_get_type(event),
+                       LIBINPUT_EVENT_POINTER_MOTION);
+
+      ptrev = libinput_event_get_pointer_event(event);
+      ck_assert(ptrev != NULL);
+
+      ev_dx = libinput_event_pointer_get_dx_noaccel(ptrev);
+      ev_dy = libinput_event_pointer_get_dy_noaccel(ptrev);
+
+      ck_assert_int_eq(dx, ev_dx);
+      ck_assert_int_eq(dy, ev_dy);
+
+      libinput_event_destroy(event);
+
+      litest_drain_events(dev->libinput);
+}
+
+START_TEST(pointer_motion_noaccel)
+{
+      struct litest_device *dev = litest_current_device();
+
+      litest_drain_events(dev->libinput);
+
+      test_noaccel_event(dev, 1, 0);
+      test_noaccel_event(dev, 1, 1);
+      test_noaccel_event(dev, 1, -1);
+      test_noaccel_event(dev, 0, 1);
+
+      test_noaccel_event(dev, -1, 0);
+      test_noaccel_event(dev, -1, 1);
+      test_noaccel_event(dev, -1, -1);
+      test_noaccel_event(dev, 0, -1);
+}
+END_TEST
+
+static void
 test_button_event(struct litest_device *dev, unsigned int button, int state)
 {
 	struct libinput *li = dev->libinput;
@@ -652,6 +703,7 @@ int main (int argc, char **argv) {
 
 	litest_add("pointer:motion", pointer_motion_relative, LITEST_RELATIVE, LITEST_ANY);
 	litest_add("pointer:motion", pointer_motion_absolute, LITEST_ABSOLUTE, LITEST_ANY);
+	litest_add("pointer:motion", pointer_motion_noaccel, LITEST_RELATIVE, LITEST_ANY);
 	litest_add("pointer:button", pointer_button, LITEST_BUTTON, LITEST_CLICKPAD);
 	litest_add_no_device("pointer:button_auto_release", pointer_button_auto_release);
 	litest_add("pointer:scroll", pointer_scroll_wheel, LITEST_WHEEL, LITEST_ANY);
-- 
1.8.5.1



More information about the wayland-devel mailing list