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diff --git a/src/widgets/doc/snippets/code/src_gui_effects_qgraphicseffect.cpp b/src/widgets/doc/snippets/code/src_gui_effects_qgraphicseffect.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
+**     the names of its contributors may be used to endorse or promote
+**     products derived from this software without specific prior written
+**     permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+MyGraphicsOpacityEffect::draw(QPainter *painter)
+{
+    // Fully opaque; draw directly without going through a pixmap.
+    if (qFuzzyCompare(m_opacity, 1)) {
+        drawSource(painter);
+        return;
+    }
+    ...
+}
+//! [0]
+
+//! [1]
+MyGraphicsEffect::draw(QPainter *painter)
+{
+    ...
+    QPoint offset;
+    if (sourceIsPixmap()) {
+        // No point in drawing in device coordinates (pixmap will be scaled anyways).
+        const QPixmap pixmap = sourcePixmap(Qt::LogicalCoordinates, &offset);
+        ...
+        painter->drawPixmap(offset, pixmap);
+    } else {
+        // Draw pixmap in device coordinates to avoid pixmap scaling;
+        const QPixmap pixmap = sourcePixmap(Qt::DeviceCoordinates, &offset);
+        painter->setWorldTransform(QTransform());
+        ...
+        painter->drawPixmap(offset, pixmap);
+    }
+    ...
+}
+//! [1]
+
+//! [2]
+...
+QLinearGradient alphaGradient(rect.topLeft(), rect.bottomLeft());
+alphaGradient.setColorAt(0.0, Qt::transparent);
+alphaGradient.setColorAt(0.5, Qt::black);
+alphaGradient.setColorAt(1.0, Qt::transparent);
+QGraphicsOpacityEffect *effect = new QGraphicsOpacityEffect;
+effect->setOpacityMask(alphaGradient);
+...
+//! [2]