Correct the detection of Windows-generated mouse events

Check only bit 8 to decide if the mouse event is generated from
a touch or pen event.

Task-number: QTBUG-33460

Change-Id: I83b23267b5de6df5e0e6b7113ecf377dd7e86c84
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/plugins/platforms/windows/qwindowsmousehandler.cpp b/src/plugins/platforms/windows/qwindowsmousehandler.cpp
index 3782b7e020..3dd8c5a0cd 100644
--- a/src/plugins/platforms/windows/qwindowsmousehandler.cpp
+++ b/src/plugins/platforms/windows/qwindowsmousehandler.cpp
@@ -168,11 +168,13 @@ bool QWindowsMouseHandler::translateMouseEvent(QWindow *window, HWND hwnd,
         return translateMouseWheelEvent(window, hwnd, msg, result);
 
 #ifndef Q_OS_WINCE
-    // Check for events synthesized from touch. Lower byte is touch index, 0 means pen.
     static const bool passSynthesizedMouseEvents = QWindowsIntegration::instance()->options() & QWindowsIntegration::PassOsMouseEventsSynthesizedFromTouch;
     if (!passSynthesizedMouseEvents) {
+        // Check for events synthesized from touch. Lower 7 bits are touch/pen index, bit 8 indicates touch.
+        // However, when tablet support is active, extraInfo is a packet serial number. This is not a problem
+        // since we do not want to ignore mouse events coming from a tablet.
         const quint64 extraInfo = GetMessageExtraInfo();
-        const bool fromTouch = (extraInfo & signatureMask) == miWpSignature && (extraInfo & 0xff);
+        const bool fromTouch = (extraInfo & signatureMask) == miWpSignature && (extraInfo & 0x80);
         if (fromTouch)
             return false;
     }