From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Wed, 17 Feb 2016 23:42:27 +0000 (+1000)
Subject: tablet: use the tilt resolution if we have it
X-Git-Tag: 1.2.0~1
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0e17dc58aa2469909d9e21d889ff119b6170e15a;p=platform%2Fupstream%2Flibinput.git

tablet: use the tilt resolution if we have it

A nonzero resolution on the tilt axes is units/rad so we can calculate the
physical min/max based. Uneven min/max ranges are supported.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Jason Gerecke <jason.gerecke@wacom.com>
---

diff --git a/src/evdev-tablet.c b/src/evdev-tablet.c
index 1e5c2cd5..22ea1ebc 100644
--- a/src/evdev-tablet.c
+++ b/src/evdev-tablet.c
@@ -231,16 +231,25 @@ adjust_tilt(const struct input_absinfo *absinfo)
 	double value = (absinfo->value - absinfo->minimum) / range;
 	const int WACOM_MAX_DEGREES = 64;
 
-	/* Map to the (-1, 1) range */
-	value = (value * 2) - 1;
-
-	/* Wacom supports physical [-64, 64] degrees, so map to that by
-	 * default. If other tablets have a different physical range or
-	 * nonzero physical offsets, they need extra treatment
-	 * here.
-	 */
+	/* If resolution is nonzero, it's in units/radian. But require
+	 * a min/max less/greater than zero so we can assume 0 is the
+	 * center */
+	if (absinfo->resolution != 0 &&
+	    absinfo->maximum > 0 &&
+	    absinfo->minimum < 0) {
+		value = 180.0/M_PI * absinfo->value/absinfo->resolution;
+	} else {
+		/* Wacom supports physical [-64, 64] degrees, so map to that by
+		 * default. If other tablets have a different physical range or
+		 * nonzero physical offsets, they need extra treatment
+		 * here.
+		 */
+		/* Map to the (-1, 1) range */
+		value = (value * 2) - 1;
+		value *= WACOM_MAX_DEGREES;
+	}
 
-	return value * WACOM_MAX_DEGREES;
+	return value;
 }
 
 static inline int32_t
diff --git a/test/tablet.c b/test/tablet.c
index c5dc892e..ad6ac458 100644
--- a/test/tablet.c
+++ b/test/tablet.c
@@ -3298,7 +3298,8 @@ START_TEST(tilt_x)
 	ck_assert_double_ge(tx, -52);
 
 	ty = libinput_event_tablet_tool_get_tilt_y(tev);
-	ck_assert_double_eq(ty, -64);
+	ck_assert_double_ge(ty, -65);
+	ck_assert_double_lt(ty, -63);
 
 	libinput_event_destroy(event);
 
@@ -3320,7 +3321,8 @@ START_TEST(tilt_x)
 		ck_assert_double_le(tx, expected_tx + 2);
 
 		ty = libinput_event_tablet_tool_get_tilt_y(tev);
-		ck_assert_double_eq(ty, -64);
+		ck_assert_double_ge(ty, -65);
+		ck_assert_double_lt(ty, -63);
 
 		libinput_event_destroy(event);
 
@@ -3365,7 +3367,8 @@ START_TEST(tilt_y)
 	ck_assert_double_ge(ty, -52);
 
 	tx = libinput_event_tablet_tool_get_tilt_x(tev);
-	ck_assert_double_eq(tx, -64);
+	ck_assert_double_ge(tx, -65);
+	ck_assert_double_lt(tx, -63);
 
 	libinput_event_destroy(event);
 
@@ -3387,7 +3390,8 @@ START_TEST(tilt_y)
 		ck_assert_double_le(ty, expected_ty + 2);
 
 		tx = libinput_event_tablet_tool_get_tilt_x(tev);
-		ck_assert_double_eq(tx, -64);
+		ck_assert_double_ge(tx, -65);
+		ck_assert_double_lt(tx, -63);
 
 		libinput_event_destroy(event);