[PATCH libinput 10/13] tablet: split point vs delta handling up

[Peter Hutterer]

Handle the delta in the end once we've updated the device state for all axes.
This requires us to use the device history rather than the current state
delta, and it also requires us to update both x and y whenever an axis change
comes in.

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
 src/evdev-tablet.c | 61 +++++++++++++++++++++++++-----------------------------
 1 file changed, 28 insertions(+), 33 deletions(-)

diff --git a/src/evdev-tablet.c b/src/evdev-tablet.c
index ff12ad5..1120598 100644
--- a/src/evdev-tablet.c
+++ b/src/evdev-tablet.c
@@ -383,17 +383,14 @@ normalize_wheel(struct tablet_dispatch *tablet,
 }
 
 static inline void
-tablet_handle_xy(struct tablet_dispatch *tablet,
-		 struct evdev_device *device,
-		 struct device_coords *point_out,
-		 struct device_coords *delta_out)
+tablet_update_xy(struct tablet_dispatch *tablet,
+		 struct evdev_device *device)
 {
-	struct device_coords point;
-	struct device_coords delta = { 0, 0 };
 	const struct input_absinfo *absinfo;
 	int value;
 
-	if (bit_is_set(tablet->changed_axes, LIBINPUT_TABLET_TOOL_AXIS_X)) {
+	if (bit_is_set(tablet->changed_axes, LIBINPUT_TABLET_TOOL_AXIS_X) ||
+	    bit_is_set(tablet->changed_axes, LIBINPUT_TABLET_TOOL_AXIS_Y)) {
 		absinfo = libevdev_get_abs_info(device->evdev, ABS_X);
 
 		if (device->left_handed.enabled)
@@ -401,14 +398,8 @@ tablet_handle_xy(struct tablet_dispatch *tablet,
 		else
 			value = absinfo->value;
 
-		if (!tablet_has_status(tablet,
-				       TABLET_TOOL_ENTERING_PROXIMITY))
-			delta.x = value - tablet->axes.point.x;
 		tablet->axes.point.x = value;
-	}
-	point.x = tablet->axes.point.x;
 
-	if (bit_is_set(tablet->changed_axes, LIBINPUT_TABLET_TOOL_AXIS_Y)) {
 		absinfo = libevdev_get_abs_info(device->evdev, ABS_Y);
 
 		if (device->left_handed.enabled)
@@ -416,28 +407,36 @@ tablet_handle_xy(struct tablet_dispatch *tablet,
 		else
 			value = absinfo->value;
 
-		if (!tablet_has_status(tablet,
-				       TABLET_TOOL_ENTERING_PROXIMITY))
-			delta.y = value - tablet->axes.point.y;
 		tablet->axes.point.y = value;
-	}
-	point.y = tablet->axes.point.y;
 
-	*delta_out = delta;
-	*point_out = point;
+		evdev_transform_absolute(device, &tablet->axes.point);
+	}
 }
 
 static inline struct normalized_coords
-tool_process_delta(struct libinput_tablet_tool *tool,
-		   const struct evdev_device *device,
-		   const struct device_coords *delta,
-		   uint64_t time)
+tablet_tool_process_delta(struct tablet_dispatch *tablet,
+			  struct libinput_tablet_tool *tool,
+			  const struct evdev_device *device,
+			  uint64_t time)
 {
 	const struct normalized_coords zero = { 0.0, 0.0 };
+	const struct tablet_axes *last, *current;
+	struct device_coords delta = { 0, 0 };
 	struct device_float_coords accel;
 
-	accel.x = 1.0 * delta->x;
-	accel.y = 1.0 * delta->y;
+	if (!tablet_has_status(tablet,
+			       TABLET_TOOL_ENTERING_PROXIMITY) &&
+	    (bit_is_set(tablet->changed_axes, LIBINPUT_TABLET_TOOL_AXIS_X) ||
+	     bit_is_set(tablet->changed_axes, LIBINPUT_TABLET_TOOL_AXIS_Y))) {
+		current = &tablet->axes;
+		last = tablet_history_get(tablet, 0);
+
+		delta.x = current->point.x - last->point.x;
+		delta.y = current->point.y - last->point.y;
+	}
+
+	accel.x = 1.0 * delta.x;
+	accel.y = 1.0 * delta.y;
 
 	if (device_float_is_zero(accel))
 		return zero;
@@ -595,7 +594,6 @@ tablet_check_notify_axes(struct tablet_dispatch *tablet,
 {
 	struct tablet_axes axes = {0};
 	const char tmp[sizeof(tablet->changed_axes)] = {0};
-	struct device_coords delta;
 	bool rc = false;
 
 	if (memcmp(tmp, tablet->changed_axes, sizeof(tmp)) == 0) {
@@ -603,8 +601,7 @@ tablet_check_notify_axes(struct tablet_dispatch *tablet,
 		goto out;
 	}
 
-	tablet_handle_xy(tablet, device, &axes.point, &delta);
-
+	tablet_update_xy(tablet, device);
 	tablet_update_pressure(tablet, device, tool);
 	tablet_update_distance(tablet, device);
 	tablet_update_slider(tablet, device);
@@ -614,6 +611,7 @@ tablet_check_notify_axes(struct tablet_dispatch *tablet,
 	 * already normalized and set if we have the mouse/lens tool */
 	tablet_update_rotation(tablet, device);
 
+	axes.point = tablet->axes.point;
 	axes.pressure = tablet->axes.pressure;
 	axes.distance = tablet->axes.distance;
 	axes.slider = tablet->axes.slider;
@@ -622,10 +620,7 @@ tablet_check_notify_axes(struct tablet_dispatch *tablet,
 	axes.wheel_discrete = tablet->axes.wheel_discrete;
 	axes.rotation = tablet->axes.rotation;
 
-	evdev_transform_absolute(device, &axes.point);
-	evdev_transform_relative(device, &delta);
-
-	axes.delta = tool_process_delta(tool, device, &delta, time);
+	axes.delta = tablet_tool_process_delta(tablet, tool, device, time);
 
 	*axes_out = axes;
 
-- 
2.9.3