window_multithreaded.h Example File

/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, 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 The Qt Company Ltd 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 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