renderthread.hpp Example File

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    #ifndef RENDERTHREAD_HPP
    #define RENDERTHREAD_HPP

    #include "block.hpp"

    #include <QtCore/QMutex>
    #include <QtCore/QThread>
    #include <QtGui/QImage>

    /**
     * The RenderThread class takes an image as input and transforms it into a list of colored rectangles (blocks)
     * that depicts the image in a more abstract way.
     * The transformation is executed in a separated worker thread and the result (the list of blocks) is reported
     * back to the Renderer as parameter of a signal.
     */
    class RenderThread : public QThread
    {
        Q_OBJECT

    public:
        RenderThread(QObject *parent = 0);
        ~RenderThread();

        // This method is called to start the transformation on the given image
        void processImage(const QImage &image);

    public Q_SLOTS:
        // This method is called whenever the user wants to stop the transformation process
        void stopProcess();

    Q_SIGNALS:
        // This signal is emitted whenever a new block has been calculated
        void sendBlock(const Block &block);

    protected:
        /**
         * This method is reimplemented from the QThread class. The content of this
         * method will be executed in the worker thread.
         */
        void run();

    private:
        // A flag to signal the worker thread that it should terminate itself
        bool m_abort;

        // A mutex to serialize the access to the m_abort flag
        QMutex mutex;

        // The image that should be transformed
        QImage m_image;
    };

    #endif