#include <osgViewer/Viewer>
#include <osgDB/ReadFile>
#include <osgText/Text>
#include <osgGA/TrackballManipulator>
#include <chrono>   
#include <osgGA/GUIEventAdapter>
#include <osgViewer/ViewerEventHandlers>

using namespace std;
using namespace chrono;

auto lastFT   = system_clock::now();
auto FT   = system_clock::now();

int main(int argc, char** argv)
{
    // 创建一个OSG Viewer对象
    osgViewer::Viewer viewer;
    viewer.setUpViewInWindow(50, 50, 800, 600);
    viewer.getCamera()->setClearColor(osg::Vec4(0.2, 0.2, 0.2, 1.0));
    viewer.setCameraManipulator(new osgGA::TrackballManipulator);

    viewer.addEventHandler(new osgViewer::StatsHandler);//查看帧数 s

    // 创建一个OSG Node对象，并加载OSG模型
    osg::ref_ptr<osg::Node> model = osgDB::readNodeFile("clock.osgt");

    // 将Node对象添加到OSG Viewer中
    viewer.setSceneData(model);
    // 启动OSG Viewer循环
    while (!viewer.done())
    {
        auto thisFT   = system_clock::now();
        auto FT = duration_cast<microseconds>(thisFT - lastFT);
        lastFT = thisFT;
        viewer.frame();
    }

    return 0;
}