osg qt多线程渲染代码

以下是一个使用 OpenSceneGraph 和 Qt 的多线程渲染代码示例：

#include <QApplication>
#include <QThread>
#include <osg/Node>
#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>
#include <osgGA/TrackballManipulator>
#include <osgQt/GraphicsWindowQt>

class RenderThread : public QThread
{
public:
    RenderThread(osgQt::GraphicsWindowQt* gw) : _gw(gw)
    {}

protected:
    void run()
    {
        osgViewer::Viewer viewer;
        viewer.setThreadingModel(osgViewer::Viewer::SingleThreaded);
        viewer.setUpViewInWindow(0, 0, _gw->width(), _gw->height());
        viewer.setSceneData(getScene());
        viewer.setCameraManipulator(new osgGA::TrackballManipulator);
        viewer.addEventHandler(new osgViewer::StatsHandler);
        _gw->setTouchEventsEnabled(true);
        viewer.setCameraManipulator(new osgGA::TrackballManipulator);
        viewer.realize();

        while (!viewer.done())
        {
            _gw->makeCurrent();
            viewer.frame();
            _gw->swapBuffers();
        }
    }

private:
    osg::ref_ptr<osg::Node> getScene()
    {
        // TODO: create your scene graph here
    }

    osgQt::GraphicsWindowQt* _gw;
};

int main(int argc, char** argv)
{
    QApplication app(argc, argv);

    osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
    traits->x = 0;
    traits->y = 0;
    traits->width = 800;
    traits->height = 600;
    traits->windowDecoration = true;
    traits->doubleBuffer = true;
    traits->sharedContext = 0;
    traits->sampleBuffers = 4;
    traits->samples = 4;

    osgQt::GraphicsWindowQt* gw = new osgQt::GraphicsWindowQt(traits.get());
    RenderThread thread(gw);
    thread.start();

    gw->show();
    gw->raise();

    int ret = app.exec();

    thread.quit();
    thread.wait();

    return ret;
}

该示例中，`RenderThread` 类是一个继承自 `QThread` 的渲染线程类。在 `run()` 函数中，我们设置了 OSG 的渲染器，并不断地进行场景渲染，直到渲染完成。`getScene()` 函数用于创建场景图。

在 `main()` 函数中，我们创建了一个 `osgQt::GraphicsWindowQt` 对象作为渲染窗口，并将其传递给 `RenderThread`。然后启动线程并显示窗口。在应用程序退出时，我们终止线程并等待其完成。