Qt 5.6 | Qt Core | Queued Custom Type Example | renderthread.cpp Example File

Qt 5.6.2 Reference Documentation

# renderthread.cpp Example File

threads/queuedcustomtype/renderthread.cpp

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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();
      }