Initial import from the monolithic Qt.

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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 184 insertions, 0 deletions

diff --git a/doc/src/snippets/code/src_corelib_concurrent_qtconcurrentmap.cpp b/doc/src/snippets/code/src_corelib_concurrent_qtconcurrentmap.cpp
new file mode 100644
index 0000000000..c48ce1e6ae
--- /dev/null
+++ b/doc/src/snippets/code/src_corelib_concurrent_qtconcurrentmap.cpp
@@ -0,0 +1,184 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** 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]
+U function(const T &t);
+//! [0]
+
+
+//! [1]
+QImage scaled(const QImage &image)
+{
+    return image.scaled(100, 100);
+}
+
+QList<QImage> images = ...;
+QFuture<QImage> thumbnails = QtConcurrent::mapped(images, scaled);
+//! [1]
+
+
+//! [2]
+U function(T &t);
+//! [2]
+
+
+//! [3]
+void scale(QImage &image)
+{
+    image = image.scaled(100, 100);
+}
+
+QList<QImage> images = ...;
+QFuture<void> future = QtConcurrent::map(images, scale);
+//! [3]
+
+
+//! [4]
+V function(T &result, const U &intermediate)
+//! [4]
+
+
+//! [5]
+void addToCollage(QImage &collage, const QImage &thumbnail)
+{
+    QPainter p(&collage);
+    static QPoint offset = QPoint(0, 0);
+    p.drawImage(offset, thumbnail);
+    offset += ...;
+}
+
+QList<QImage> images = ...;
+QFuture<QImage> collage = QtConcurrent::mappedReduced(images, scaled, addToCollage);
+//! [5]
+
+
+//! [6]
+QList<QImage> images = ...;
+
+QFuture<QImage> thumbnails = QtConcurrent::mapped(images.constBegin(), images.constEnd(), scaled);
+
+// map in-place only works on non-const iterators
+QFuture<void> future = QtConcurrent::map(images.begin(), images.end(), scale);
+
+QFuture<QImage> collage = QtConcurrent::mappedReduced(images.constBegin(), images.constEnd(), scaled, addToCollage);
+//! [6]
+
+
+//! [7]
+QList<QImage> images = ...;
+
+// each call blocks until the entire operation is finished
+QList<QImage> future = QtConcurrent::blockingMapped(images, scaled);
+
+QtConcurrent::blockingMap(images, scale);
+
+QImage collage = QtConcurrent::blockingMappedReduced(images, scaled, addToCollage);
+//! [7]
+
+
+//! [8]
+// squeeze all strings in a QStringList
+QStringList strings = ...;
+QFuture<void> squeezedStrings = QtConcurrent::map(strings, &QString::squeeze);
+
+// swap the rgb values of all pixels on a list of images
+QList<QImage> images = ...;
+QFuture<QImage> bgrImages = QtConcurrent::mapped(images, &QImage::rgbSwapped);
+
+// create a set of the lengths of all strings in a list
+QStringList strings = ...;
+QFuture<QSet<int> > wordLengths = QtConcurrent::mappedReduced(string, &QString::length, &QSet<int>::insert);
+//! [8]
+
+
+//! [9]
+// can mix normal functions and member functions with QtConcurrent::mappedReduced()
+
+// compute the average length of a list of strings
+extern void computeAverage(int &average, int length);
+QStringList strings = ...;
+QFuture<int> averageWordLength = QtConcurrent::mappedReduced(strings, &QString::length, computeAverage);
+
+// create a set of the color distribution of all images in a list
+extern int colorDistribution(const QImage &string);
+QList<QImage> images = ...;
+QFuture<QSet<int> > totalColorDistribution = QtConcurrent::mappedReduced(images, colorDistribution, QSet<int>::insert);
+//! [9]
+
+
+//! [10]
+QImage QImage::scaledToWidth(int width, Qt::TransformationMode) const;
+//! [10]
+
+
+//! [11]
+boost::bind(&QImage::scaledToWidth, 100, Qt::SmoothTransformation)
+//! [11]
+
+
+//! [12]
+QImage scaledToWith(const QImage &image)
+//! [12]
+
+
+//! [13]
+QList<QImage> images = ...;
+QFuture<QImage> thumbnails = QtConcurrent::mapped(images, boost::bind(&QImage::scaledToWidth, 100 Qt::SmoothTransformation));
+//! [13]
+
+//! [14]
+struct Scaled
+{
+    Scaled(int size)
+    : m_size(size) { }
+
+    typedef QImage result_type;
+
+    QImage operator()(const QImage &image)
+    {
+        return image.scaled(m_size, m_size);
+    }
+
+    int m_size;
+};
+
+QList<QImage> images = ...;
+QFuture<QImage> thumbnails = QtConcurrent::mapped(images, Scaled(100));
+//! [14]