window_multithreaded.h Example File

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  #ifndef WINDOW_MULTITHREADED_H
  #define WINDOW_MULTITHREADED_H

  #include <QWindow>
  #include <QMatrix4x4>
  #include <QThread>
  #include <QWaitCondition>
  #include <QMutex>

  QT_FORWARD_DECLARE_CLASS(QOpenGLContext)
  QT_FORWARD_DECLARE_CLASS(QOpenGLFramebufferObject)
  QT_FORWARD_DECLARE_CLASS(QOffscreenSurface)
  QT_FORWARD_DECLARE_CLASS(QQuickRenderControl)
  QT_FORWARD_DECLARE_CLASS(QQuickWindow)
  QT_FORWARD_DECLARE_CLASS(QQmlEngine)
  QT_FORWARD_DECLARE_CLASS(QQmlComponent)
  QT_FORWARD_DECLARE_CLASS(QQuickItem)

  class CubeRenderer;

  class QuickRenderer : public QObject
  {
      Q_OBJECT

  public:
      QuickRenderer();

      void requestInit();
      void requestRender();
      void requestResize();
      void requestStop();

      QWaitCondition *cond() { return &m_cond; }
      QMutex *mutex() { return &m_mutex; }

      void setContext(QOpenGLContext *ctx) { m_context = ctx; }
      void setSurface(QOffscreenSurface *s) { m_surface = s; }
      void setWindow(QWindow *w) { m_window = w; }
      void setQuickWindow(QQuickWindow *w) { m_quickWindow = w; }
      void setRenderControl(QQuickRenderControl *r) { m_renderControl = r; }

      void aboutToQuit();

  private:
      bool event(QEvent *e) override;
      void init();
      void cleanup();
      void ensureFbo();
      void render(QMutexLocker *lock);

      QWaitCondition m_cond;
      QMutex m_mutex;
      QOpenGLContext *m_context;
      QOffscreenSurface *m_surface;
      QOpenGLFramebufferObject *m_fbo;
      QWindow *m_window;
      QQuickWindow *m_quickWindow;
      QQuickRenderControl *m_renderControl;
      CubeRenderer *m_cubeRenderer;
      QMutex m_quitMutex;
      bool m_quit;
  };

  class WindowMultiThreaded : public QWindow
  {
      Q_OBJECT

  public:
      WindowMultiThreaded();
      ~WindowMultiThreaded();

  protected:
      void exposeEvent(QExposeEvent *e) override;
      void resizeEvent(QResizeEvent *e) override;
      void mousePressEvent(QMouseEvent *e) override;
      void mouseReleaseEvent(QMouseEvent *e) override;
      bool event(QEvent *e) override;

  private slots:
      void run();
      void requestUpdate();
      void polishSyncAndRender();

  private:
      void startQuick(const QString &filename);
      void updateSizes();

      QuickRenderer *m_quickRenderer;
      QThread *m_quickRendererThread;

      QOpenGLContext *m_context;
      QOffscreenSurface *m_offscreenSurface;
      QQuickRenderControl *m_renderControl;
      QQuickWindow *m_quickWindow;
      QQmlEngine *m_qmlEngine;
      QQmlComponent *m_qmlComponent;
      QQuickItem *m_rootItem;
      bool m_quickInitialized;
      bool m_psrRequested;
  };

  #endif