File 0001-Avoid-providing-bad-pixelDeltas-on-X11.patch of Package libqt5-qtbase
From d196036024697a75868c1f1626525710495ca428 Mon Sep 17 00:00:00 2001
From: Allan Sandfeld Jensen <allan.jensen@qt.io>
Date: Thu, 23 Nov 2017 14:25:04 +0100
Subject: [PATCH] Avoid providing bad pixelDeltas on X11
With libinput we now get a hardcoded resolution that is unrelated to
the hardware. So avoid using that as a real pixel delta and document
pixel deltas as being driver specific and unreliable on X11.
Task-number: QTBUG-59261
Change-Id: I9fe86d80e7ccd290ed2e4091d7eafa52cb537d34
Reviewed-by: David Edmundson <davidedmundson@kde.org>
Reviewed-by: Marco Martin <mart@kde.org>
Reviewed-by: Gatis Paeglis <gatis.paeglis@qt.io>
---
src/gui/kernel/qevent.cpp | 1 +
src/plugins/platforms/xcb/qxcbconnection_xi2.cpp | 14 ++++++++------
2 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/src/gui/kernel/qevent.cpp b/src/gui/kernel/qevent.cpp
index 06d52aa..c68f9af 100644
--- a/src/gui/kernel/qevent.cpp
+++ b/src/gui/kernel/qevent.cpp
@@ -971,6 +971,7 @@ QWheelEvent::QWheelEvent(const QPointF &pos, const QPointF& globalPos,
\li scrolling is about to begin, but the distance did not yet change (Qt::ScrollBegin),
\li or scrolling has ended and the distance did not change anymore (Qt::ScrollEnd).
\endlist
+ \note On X11 this value is driver specific and unreliable, use angleDelta() instead
*/
/*!
diff --git a/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp b/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp
index d1d97af..94f543f 100644
--- a/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection_xi2.cpp
@@ -953,10 +953,12 @@ void QXcbConnection::xi2HandleScrollEvent(void *event, ScrollingDevice &scrollin
double delta = scrollingDevice.lastScrollPosition.y() - value;
scrollingDevice.lastScrollPosition.setY(value);
angleDelta.setY((delta / scrollingDevice.verticalIncrement) * 120);
- // We do not set "pixel" delta if it is only measured in ticks.
- if (scrollingDevice.verticalIncrement > 1)
+ // With most drivers the increment is 1 for wheels.
+ // For libinput it is hardcoded to a useless 15.
+ // For a proper touchpad driver it should be in the same order of magnitude as 120
+ if (scrollingDevice.verticalIncrement > 15)
rawDelta.setY(delta);
- else if (scrollingDevice.verticalIncrement < -1)
+ else if (scrollingDevice.verticalIncrement < -15)
rawDelta.setY(-delta);
}
}
@@ -965,10 +967,10 @@ void QXcbConnection::xi2HandleScrollEvent(void *event, ScrollingDevice &scrollin
double delta = scrollingDevice.lastScrollPosition.x() - value;
scrollingDevice.lastScrollPosition.setX(value);
angleDelta.setX((delta / scrollingDevice.horizontalIncrement) * 120);
- // We do not set "pixel" delta if it is only measured in ticks.
- if (scrollingDevice.horizontalIncrement > 1)
+ // See comment under vertical
+ if (scrollingDevice.horizontalIncrement > 15)
rawDelta.setX(delta);
- else if (scrollingDevice.horizontalIncrement < -1)
+ else if (scrollingDevice.horizontalIncrement < -15)
rawDelta.setX(-delta);
}
}
--
2.7.4
