Deliver stationary touchpoints that have changed pressure

As a rule, we don't deliver touch events containing only stationary
touchpoints.  To fix QTBUG-52510 we added an exception in
1bd0ab7050304d9e8989cde77e486947c56b9696 : if the velocity changed,
deliver it anyway.  Now we need to do the same if the pressure changed.

Also, on the customer's hardware, pressure is indicated via ABS_MT_PRESSURE.

Change-Id: If7f7088df055d686cdd86967b999e38024f8170f
Fixes: QTBUG-77142
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>

2 files changed, 8 insertions, 4 deletions

diff --git a/src/gui/kernel/qguiapplication.cpp b/src/gui/kernel/qguiapplication.cpp
index 359d182dd9..51cde72fa1 100644
--- a/src/gui/kernel/qguiapplication.cpp
+++ b/src/gui/kernel/qguiapplication.cpp
@@ -2695,7 +2695,7 @@ void QGuiApplicationPrivate::processTouchEvent(QWindowSystemInterfacePrivate::To
     QWindow *window = e->window.data();
     typedef QPair<Qt::TouchPointStates, QList<QTouchEvent::TouchPoint> > StatesAndTouchPoints;
     QHash<QWindow *, StatesAndTouchPoints> windowsNeedingEvents;
-    bool stationaryTouchPointChangedVelocity = false;
+    bool stationaryTouchPointChangedProperty = false;
 
     for (int i = 0; i < e->points.count(); ++i) {
         QTouchEvent::TouchPoint touchPoint = e->points.at(i);
@@ -2775,7 +2775,11 @@ void QGuiApplicationPrivate::processTouchEvent(QWindowSystemInterfacePrivate::To
             if (touchPoint.state() == Qt::TouchPointStationary) {
                 if (touchInfo.touchPoint.velocity() != touchPoint.velocity()) {
                     touchInfo.touchPoint.setVelocity(touchPoint.velocity());
-                    stationaryTouchPointChangedVelocity = true;
+                    stationaryTouchPointChangedProperty = true;
+                }
+                if (!qFuzzyCompare(touchInfo.touchPoint.pressure(), touchPoint.pressure())) {
+                    touchInfo.touchPoint.setPressure(touchPoint.pressure());
+                    stationaryTouchPointChangedProperty = true;
                 }
             } else {
                 touchInfo.touchPoint = touchPoint;
@@ -2816,7 +2820,7 @@ void QGuiApplicationPrivate::processTouchEvent(QWindowSystemInterfacePrivate::To
             break;
         case Qt::TouchPointStationary:
             // don't send the event if nothing changed
-            if (!stationaryTouchPointChangedVelocity)
+            if (!stationaryTouchPointChangedProperty)
                 continue;
             Q_FALLTHROUGH();
         default:
diff --git a/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp b/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp
index f3cc160b3e..b5bd2dcff4 100644
--- a/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp
+++ b/src/platformsupport/input/evdevtouch/qevdevtouchhandler.cpp
@@ -532,7 +532,7 @@ void QEvdevTouchScreenData::processInputEvent(input_event *data)
                 m_currentData.state = Qt::TouchPointReleased;
             if (m_typeB)
                 m_contacts[m_currentSlot].maj = m_currentData.maj;
-        } else if (data->code == ABS_PRESSURE) {
+        } else if (data->code == ABS_PRESSURE || data->code == ABS_MT_PRESSURE) {
             m_currentData.pressure = qBound(hw_pressure_min, data->value, hw_pressure_max);
             if (m_typeB || m_singleTouch)
                 m_contacts[m_currentSlot].pressure = m_currentData.pressure;