Disable event compression when the tablet events are accepted

Since Qt 4.5, all tablet events are compressed not to overload the
widgets with the corresponding mouse event (a mouse event is generated
if the tablet event is not accepted).

This behavior reduce the precision when drawing on a widget that use
the tablet events. All tablet events should be sent to the widget that
are accepting the tablet event.

With this patch, the tablet event are filtered only if the widget
ignore the first tablet event. The mouse events are compressed.

There is two special cases for the filtering:

First, if a tablet event is for another widget than the one
ignoring the tablet, this event should not be filtered.

Second, if there is a mouse press event, the mouse move event should be
sent to the widget that received the mouse press event.

Helped-by: Pierre Rossi
Reviewed-by: Thomas Zander
Reviewed-by: Bradley T. Hughes

8 files changed, 254 insertions, 21 deletions

diff --git a/tests/manual/qtabletevent/device_information/main.cpp b/tests/manual/qtabletevent/device_information/main.cpp
new file mode 100644
index 0000000000..0c2eda393e
--- /dev/null
+++ b/tests/manual/qtabletevent/device_information/main.cpp
@@ -0,0 +1,50 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui>
+#include "tabletwidget.h"
+
+int main(int argc, char **argv) {
+  QApplication app(argc, argv);
+  TabletWidget tabletWidget;
+  tabletWidget.showMaximized();
+  return app.exec();
+}
diff --git a/tests/manual/qtabletevent/qtabletevent.pro b/tests/manual/qtabletevent/device_information/qtabletevent.pro
index e0ed549004..e0ed549004 100644
--- a/tests/manual/qtabletevent/qtabletevent.pro
+++ b/tests/manual/qtabletevent/device_information/qtabletevent.pro
diff --git a/tests/manual/qtabletevent/tabletwidget.cpp b/tests/manual/qtabletevent/device_information/tabletwidget.cpp
index 15a3d8086a..15a3d8086a 100644
--- a/tests/manual/qtabletevent/tabletwidget.cpp
+++ b/tests/manual/qtabletevent/device_information/tabletwidget.cpp
diff --git a/tests/manual/qtabletevent/tabletwidget.h b/tests/manual/qtabletevent/device_information/tabletwidget.h
index d3ccb32ef9..b16e9ed363 100644
--- a/tests/manual/qtabletevent/tabletwidget.h
+++ b/tests/manual/qtabletevent/device_information/tabletwidget.h
@@ -9,8 +9,8 @@
 ** No Commercial Usage
 ** This file contains pre-release code and may not be distributed.
 ** You may use this file in accordance with the terms and conditions
-** contained in the Technology Preview License Agreement accompanying
-** this package.
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
 **
 ** GNU Lesser General Public License Usage
 ** Alternatively, this file may be used under the terms of the GNU Lesser
@@ -21,20 +21,20 @@
 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
 **
 ** In addition, as a special exception, Nokia gives you certain
-** additional rights.  These rights are described in the Nokia Qt LGPL
-** Exception version 1.1, included in the file LGPL_EXCEPTION.txt in this
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
 ** package.
 **
-** If you have questions regarding the use of this file, please contact
-** Nokia at qt-info@nokia.com.
-**
-**
-**
-**
-**
-**
-**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
 **
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/
diff --git a/tests/manual/qtabletevent/event_compression/event_compression.pro b/tests/manual/qtabletevent/event_compression/event_compression.pro
new file mode 100644
index 0000000000..273fd6c1b0
--- /dev/null
+++ b/tests/manual/qtabletevent/event_compression/event_compression.pro
@@ -0,0 +1,7 @@
+TEMPLATE = app
+QT += testlib
+
+# Input
+SOURCES += main.cpp \
+    mousestatwidget.cpp
+HEADERS += mousestatwidget.h
diff --git a/tests/manual/qtabletevent/event_compression/main.cpp b/tests/manual/qtabletevent/event_compression/main.cpp
new file mode 100644
index 0000000000..3b869e333f
--- /dev/null
+++ b/tests/manual/qtabletevent/event_compression/main.cpp
@@ -0,0 +1,58 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "mousestatwidget.h"
+
+#include <QApplication>
+#include <QWidget>
+#include <QVBoxLayout>
+
+int main(int argc, char **argv){
+  QApplication app(argc, argv);
+
+  QWidget main;
+  QVBoxLayout *layout = new QVBoxLayout(&main);
+  layout->addWidget(new MouseStatWidget(true));
+  layout->addWidget(new MouseStatWidget(false));
+  main.resize(800, 600);
+  main.show();
+  return app.exec();
+}
diff --git a/tests/manual/qtabletevent/event_compression/mousestatwidget.cpp b/tests/manual/qtabletevent/event_compression/mousestatwidget.cpp
new file mode 100644
index 0000000000..024e14a149
--- /dev/null
+++ b/tests/manual/qtabletevent/event_compression/mousestatwidget.cpp
@@ -0,0 +1,99 @@
+#include "mousestatwidget.h"
+
+#include <QTabletEvent>
+#include <QPainter>
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights.  These rights are described in the Nokia Qt LGPL
+** Exception version 1.1, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QTextOption>
+#include <QTest>
+
+MouseStatWidget::MouseStatWidget(bool acceptTabletEvent):acceptTabletEvent(acceptTabletEvent),
+    receivedMouseEventCount(0),
+    receivedMouseEventCountToPaint(0),
+    receivedTabletEventCount(0),
+    receivedTabletEventCountToPaint(0)
+{
+    startTimer(1000);
+}
+
+
+void MouseStatWidget::tabletEvent(QTabletEvent *event)
+{
+    ++receivedTabletEventCount;
+    if (acceptTabletEvent)
+        event->accept();
+    else
+        event->ignore();
+    // make sure the event loop is slow
+    QTest::qSleep(15);
+}
+
+void MouseStatWidget::mouseMoveEvent(QMouseEvent *)
+{
+    ++receivedMouseEventCount;
+}
+
+void MouseStatWidget::timerEvent(QTimerEvent *)
+{
+    receivedMouseEventCountToPaint = receivedMouseEventCount;
+    receivedTabletEventCountToPaint = receivedTabletEventCount;
+    receivedMouseEventCount = 0;
+    receivedTabletEventCount = 0;
+    update();
+}
+
+void MouseStatWidget::paintEvent(QPaintEvent *)
+{
+    QPainter painter(this);
+    painter.setPen(Qt::black);
+    painter.drawRect(rect());
+    QStringList text;
+    text << ((acceptTabletEvent) ? " - tablet events accepted - " : " - tablet events ignored - ");
+    text << QString("Number of tablet events received in the last second: %1").arg(QString::number(receivedTabletEventCountToPaint));
+    text << QString("Number of mouse events received in the last second: %1").arg(QString::number(receivedMouseEventCountToPaint));
+
+    QTextOption textOption(Qt::AlignCenter);
+    textOption.setWrapMode(QTextOption::WrapAtWordBoundaryOrAnywhere);
+    painter.drawText(rect(),
+                     text.join("\n"),
+                     textOption);
+}
diff --git a/tests/manual/qtabletevent/main.cpp b/tests/manual/qtabletevent/event_compression/mousestatwidget.h
index 44afcafc46..22c0dffcad 100644
--- a/tests/manual/qtabletevent/main.cpp
+++ b/tests/manual/qtabletevent/event_compression/mousestatwidget.h
@@ -39,12 +39,31 @@
 **
 ****************************************************************************/
 
-#include <QtGui>
-#include "tabletwidget.h"
+#ifndef MOUSESTATWIDGET_H
+#define MOUSESTATWIDGET_H
 
-int main(int argc, char **argv) {
-  QApplication app(argc, argv);
-  TabletWidget tabletWidget;
-  tabletWidget.showMaximized();
-  return app.exec();
-} 
+#include <QWidget>
+
+class QTabletEvent;
+class QMouseEvent;
+class QTimerEvent;
+class QPaintEvent;
+
+class MouseStatWidget : public QWidget
+{
+public:
+    MouseStatWidget(bool acceptTabletEvent = true);
+protected:
+    void tabletEvent(QTabletEvent *);
+    void mouseMoveEvent(QMouseEvent *);
+    void timerEvent(QTimerEvent *);
+    void paintEvent(QPaintEvent *);
+private:
+    const bool acceptTabletEvent;
+    int receivedMouseEventCount;
+    int receivedMouseEventCountToPaint;
+    int receivedTabletEventCount;
+    int receivedTabletEventCountToPaint;
+};
+
+#endif // MOUSESTATWIDGET_H