#include <Windows.h>

#include <osg/GraphicsContext>

#include <osg/Group>

#include <osg/Node>

#include <osg/Geode>

#include <osgViewer/Viewer>

#include <osgDB/ReadFile>

#include <osgUtil/Optimizer>

#include <osgDB/WriteFile>

#include <osgGA/TrackballManipulator>

osg::ref_ptr<osg::Image> captureImage = new osg::Image;

osg::ref_ptr<osgGA::TrackballManipulator> track = new osgGA::TrackballManipulator;

osg::Vec3d center;

int captureAngelCount = ;

osg::Vec3d shotEye[];

osg::Vec3d shotup[];

struct CaptureCallback :public osg::Camera::DrawCallback

{

    CaptureCallback()

    {

    }

    ~CaptureCallback() {}

    virtual void operator()(const osg::Camera &camera) const

    {

        //得到窗口系统接口

        osg::ref_ptr<osg::GraphicsContext::WindowingSystemInterface> wsi = osg::GraphicsContext::getWindowingSystemInterface();

        unsigned int width, height;

        //得到分辨率

        wsi->getScreenResolution(osg::GraphicsContext::ScreenIdentifier(), width, height);

        static int cnt = ;

        //读取像素信息抓图

        captureImage->readPixels((width - ) / , (height - ) / , , , GL_RGBA, GL_UNSIGNED_BYTE);

        char filename[];

        sprintf(filename, "ScreenShot//ScreenShot%d.png", cnt++);

        osgDB::writeImageFile(*captureImage, filename);

    }

};

int CountLines(char *filename)

{

    std::ifstream ReadFile;

    int n = ;

    std::string tmp;

    ReadFile.open(filename, std::ios::in);//ios::in 表示以只读的方式读取文件

    if (ReadFile.fail())//文件打开失败:返回0

    {

        return ;

    }

    else//文件存在

    {

        while (getline(ReadFile, tmp, '\n'))

        {

            n++;

        }

        ReadFile.close();

        return n;

    }

}

int main()

{

    osg::ref_ptr<osgViewer::Viewer> viewer = new osgViewer::Viewer;

    osg::ref_ptr<osg::Group> root = new osg::Group;

    osg::ref_ptr<osg::Node>node = osgDB::readNodeFile("F://C++代码//CaptureTest//tio//osg_vertex_visitor_test//model2.ive");

    root->addChild(node);

    osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;

    {

        traits->x = ;

        traits->y = ;

        traits->width = ;

        traits->height = ;

        //支持窗口扩展，默认是不支持的

        traits->windowDecoration = true;

        //支持双缓存，默认不支持

        traits->doubleBuffer = true;

        traits->sharedContext = ;

        traits->red = ;

        traits->blue = ;

        traits->green = ;

        //支持alpha，默认不支持为0，这里改为支持，使截出来的图片具有alpha值

        traits->alpha = ;

        osg::ref_ptr<osg::GraphicsContext> gc = osg::GraphicsContext::createGraphicsContext(traits.get());

        if (gc.valid())

        {

            std::cout << "create gc success" << std::endl;

        }

        double fovy, aspectRatio, zNear, zFar;

        viewer->getCamera()->getProjectionMatrixAsPerspective(fovy, aspectRatio, zNear, zFar);

        double newAspectRatio = double(traits->width) / double(traits->height);

        double aspectRatioChange = newAspectRatio / aspectRatio;

        if (aspectRatioChange != 1.0)

        {

            viewer->getCamera()->getProjectionMatrix() *= osg::Matrix::scale(1.0 / aspectRatioChange, 1.0, 1.0);

        }

        viewer->getCamera()->setViewport(, , , );

        viewer->getCamera()->setClearColor(osg::Vec4(, , , ));

        viewer->setCameraManipulator(track);

        viewer->getCamera()->setGraphicsContext(gc.get());

        osgUtil::Optimizer optimizer;

        optimizer.optimize(root.get());

        viewer->setSceneData(root.get());

        viewer->realize();

        viewer->getCamera()->setFinalDrawCallback(new CaptureCallback());

    }

    {

        const osg::BoundingSphere bs = node->getBound();

        std::cout << "NodeRadius: " << bs.radius() << std::endl;

        //设置getTextureDistance以后开始使用贴图

        //float getTextureDistance = 1000000.0f;

        float getTextureDistance = bs.radius() * ;

        osg::Vec3 viewDirection[];

        center = bs.center();

        //读取拍照点，并求up值集合

        {

            std::ifstream file;

            int LINES;

            char filename[] = "shotEye258.txt";

            file.open(filename, std::ios::in);

            if (file.fail())

            {

                std::cout << "文件不存在." << std::endl;

                file.close();

            }

            else//文件存在

            {

                LINES = CountLines(filename);

                while (LINES--) //读取数据到数组

                {

                    float a, b, c;

                    file >> a;

                    file >> b;

                    file >> c;

                    viewDirection[++captureAngelCount].set(a, b, c);

                }

            }

            file.close();

            for (int i = ; i <= captureAngelCount; i++)

            {

                shotEye[i] = center + viewDirection[i] * getTextureDistance;

            }

            int cnt = ;

            for (int i = ; i <= captureAngelCount; i++)

            {

                osg::Vec3 temp = center - shotEye[i];

                //如果与X轴平行，那么与Y轴叉乘

                if ((temp^osg::Vec3(, , )) == osg::Vec3(, , ))

                {

                    cnt++;

                    shotup[i] = temp^osg::Vec3(, , );

                    shotup[i].normalize();

                }

                else

                {

                    shotup[i] = temp^osg::Vec3(, , );

                    shotup[i].normalize();

                }

            }

        }

    }

    static int cnt = ;

        for (; cnt <= captureAngelCount; cnt++)

        {

            track->setByInverseMatrix(osg::Matrix::lookAt(shotEye[cnt], center, shotup[cnt]));

            viewer->frame();

            //Sleep(100);

        }

    return ;

}