renderthread.cpp Example File

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 #include "renderthread.h"

 RenderThread::RenderThread(QObject *parent)
     : QThread(parent)
 {
     m_abort = false;
 }

 RenderThread::~RenderThread()
 {
     mutex.lock();
     m_abort = true;
     mutex.unlock();

     wait();
 }

 void RenderThread::processImage(const QImage &image)
 {
     if (image.isNull())
         return;

     m_image = image;
     m_abort = false;
     start();
 }

 void RenderThread::run()
 {
     int size = qMax(m_image.width()/20, m_image.height()/20);
     for (int s = size; s > 0; --s) {
         for (int c = 0; c < 400; ++c) {
             int x1 = qMax(0, (qrand() % m_image.width()) - s/2);
             int x2 = qMin(x1 + s/2 + 1, m_image.width());
             int y1 = qMax(0, (qrand() % m_image.height()) - s/2);
             int y2 = qMin(y1 + s/2 + 1, m_image.height());
             int n = 0;
             int red = 0;
             int green = 0;
             int blue = 0;
             for (int i = y1; i < y2; ++i) {
                 for (int j = x1; j < x2; ++j) {
                     QRgb pixel = m_image.pixel(j, i);
                     red += qRed(pixel);
                     green += qGreen(pixel);
                     blue += qBlue(pixel);
                     n += 1;
                 }
             }
             Block block(QRect(x1, y1, x2 - x1 + 1, y2 - y1 + 1),
                         QColor(red/n, green/n, blue/n));
             emit sendBlock(block);
             if (m_abort)
                 return;
             msleep(10);
         }
     }
 }

 void RenderThread::stopProcess()
 {
     mutex.lock();
     m_abort = true;
     mutex.unlock();
 }