Move the QtMultimedia spectrum demo to QtMultimediaKit

Change-Id: I60d7897eb84dfbe2ce5af5adeb23b33270aa7d7c
Reviewed-on: http://codereview.qt.nokia.com/1483
Reviewed-by: Jonas Rabbe <jonas.rabbe@nokia.com>

1 files changed, 203 insertions, 0 deletions

diff --git a/examples/spectrum/app/waveform.h b/examples/spectrum/app/waveform.h
new file mode 100644
index 000000000..2d3a4883f
--- /dev/null
+++ b/examples/spectrum/app/waveform.h
@@ -0,0 +1,203 @@
+/****************************************************************************
+**
+** 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 examples 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."
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef WAVEFORM_H
+#define WAVEFORM_H
+
+#include <QWidget>
+#include <QtMultimediaKit/QAudioFormat>
+#include <QPixmap>
+#include <QScopedPointer>
+
+QT_FORWARD_DECLARE_CLASS(QByteArray)
+
+/**
+ * Widget which displays a section of the audio waveform.
+ *
+ * The waveform is rendered on a set of QPixmaps which form a group of tiles
+ * whose extent covers the widget.  As the audio position is updated, these
+ * tiles are scrolled from left to right; when the left-most tile scrolls
+ * outside the widget, it is moved to the right end of the tile array and
+ * painted with the next section of the waveform.
+ */
+class Waveform : public QWidget {
+    Q_OBJECT
+public:
+    Waveform(QWidget *parent = 0);
+    ~Waveform();
+
+    // QWidget
+    void paintEvent(QPaintEvent *event);
+    void resizeEvent(QResizeEvent *event);
+
+    void initialize(const QAudioFormat &format, qint64 audioBufferSize, qint64 windowDurationUs);
+    void reset();
+
+    void setAutoUpdatePosition(bool enabled);
+
+public slots:
+    void bufferChanged(qint64 position, qint64 length, const QByteArray &buffer);
+    void audioPositionChanged(qint64 position);
+
+private:
+    static const int NullIndex = -1;
+
+    void deletePixmaps();
+
+    /*
+     * (Re)create all pixmaps, repaint and update the display.
+     * Triggers an update();
+     */
+    void createPixmaps(const QSize &newSize);
+
+    /*
+     * Update window position.
+     * Triggers an update().
+     */
+    void setWindowPosition(qint64 position);
+
+    /*
+     * Base position of tile
+     */
+    qint64 tilePosition(int index) const;
+
+    /*
+     * Structure which identifies a point within a given
+     * tile.
+     */
+    struct TilePoint
+    {
+        TilePoint(int idx = 0, qint64 pos = 0, qint64 pix = 0)
+        :   index(idx), positionOffset(pos), pixelOffset(pix)
+        { }
+
+        // Index of tile
+        int     index;
+
+        // Number of bytes from start of tile
+        qint64  positionOffset;
+
+        // Number of pixels from left of corresponding pixmap
+        int     pixelOffset;
+    };
+
+    /*
+     * Convert position in m_buffer into a tile index and an offset in pixels
+     * into the corresponding pixmap.
+     *
+     * \param position  Offset into m_buffer, in bytes
+
+     * If position is outside the tile array, index is NullIndex and
+     * offset is zero.
+     */
+    TilePoint tilePoint(qint64 position) const;
+
+    /*
+     * Convert offset in bytes into a tile into an offset in pixels
+     * within that tile.
+     */
+    int tilePixelOffset(qint64 positionOffset) const;
+
+    /*
+     * Convert offset in bytes into the window into an offset in pixels
+     * within the widget rect().
+     */
+    int windowPixelOffset(qint64 positionOffset) const;
+
+    /*
+     * Paint all tiles which can be painted.
+     * \return true iff update() was called
+     */
+    bool paintTiles();
+
+    /*
+     * Paint the specified tile
+     *
+     * \pre Sufficient data is available to completely paint the tile, i.e.
+     *      m_dataLength is greater than the upper bound of the tile.
+     */
+    void paintTile(int index);
+
+    /*
+     * Move the first n tiles to the end of the array, and mark them as not
+     * painted.
+     */
+    void shuffleTiles(int n);
+
+    /*
+     * Reset tile array
+     */
+    void resetTiles(qint64 newStartPos);
+
+private:
+    qint64                  m_bufferPosition;
+    qint64                  m_bufferLength;
+    QByteArray              m_buffer;
+
+    qint64                  m_audioPosition;
+    QAudioFormat            m_format;
+
+    bool                    m_active;
+
+    QSize                   m_pixmapSize;
+    QVector<QPixmap*>       m_pixmaps;
+
+    struct Tile {
+        // Pointer into parent m_pixmaps array
+        QPixmap*            pixmap;
+
+        // Flag indicating whether this tile has been painted
+        bool                painted;
+    };
+
+    QVector<Tile>           m_tiles;
+
+    // Length of audio data in bytes depicted by each tile
+    qint64                  m_tileLength;
+
+    // Position in bytes of the first tile, relative to m_buffer
+    qint64                  m_tileArrayStart;
+
+    qint64                  m_windowPosition;
+    qint64                  m_windowLength;
+
+};
+
+#endif // WAVEFORM_H