MFC加载大型osg模型

MFC加载模型，发现打开 Navid 缓冲等选项后，加载大型模型的速度就快了很多。

#include "stdafx.h"
#include "OSGObject.h"


COSGObject::COSGObject(HWND hWnd)
{
    m_hwnd = hWnd;
}


COSGObject::~COSGObject()
{

}

void COSGObject::InitOSG()
{
    InitSceneGraph();
    InitCameraConfig();
}

void COSGObject::InitSceneGraph()
{
    mRoot = new osg::Group;
    //mRoot->addChild(osgDB::readNodeFile("D://library.OSGB"));
    //mRoot->addChild(osgDB::readNodeFile("I:\BIM\osg\pzy20190722.OSGB"));
    //mRoot->addChild(osgDB::readNodeFile("D:\参考手册\BIM\ive\build20190628.ive"));
    mRoot->addChild(osgDB::readNodeFile("I:\BIM\osg\wanluowang20190903.OSGB"));

}

void COSGObject::InitCameraConfig()
{
    RECT rect1;
    mViewer = new osgViewer::Viewer;
    ::GetWindowRect(m_hwnd, &rect1);
    osg::ref_ptr<osg::GraphicsContext::Traits> traits1 = new osg::GraphicsContext::Traits;
    osg::ref_ptr<osg::Referenced> windata = new osgViewer::GraphicsWindowWin32::WindowData(m_hwnd);

    traits1->x = 0;
    traits1->y = 0;
    traits1->width = rect1.right - rect1.left;
    traits1->height = rect1.bottom - rect1.top;

    traits1->windowDecoration = false;
    traits1->doubleBuffer = true;
    traits1->sharedContext = 0;
    traits1->setInheritedWindowPixelFormat = true;

    traits1->inheritedWindowData = windata;
    osg::GraphicsContext* gc1 = osg::GraphicsContext::createGraphicsContext(traits1);
    osg::ref_ptr<osg::Camera> camera1 = new osg::Camera;
    camera1->setGraphicsContext(gc1);

    camera1->setViewport(new osg::Viewport(traits1->x, traits1->y,traits1->width,traits1->height));
    camera1->setProjectionMatrixAsPerspective(30.3f, static_cast<double>(traits1->width) / static_cast<double>(traits1->height), 1.0, 1000.0);

    mViewer->setCamera(camera1);
    mViewer->setCameraManipulator(new osgGA::TrackballManipulator);
    mViewer->setSceneData(mRoot);
    mViewer->realize();

    mViewer->getCamera()->setComputeNearFarMode(osg::CullSettings::COMPUTE_NEAR_USING_PRIMITIVES);
    mViewer->getCamera()->setNearFarRatio(0.000003f);

}

void COSGObject::PreFrameUpdate()
{

}

void COSGObject::PostFrameUpdate()
{

}

void COSGObject::Render(void* ptr)
{
    COSGObject* osgObj = (COSGObject*)ptr;
    osgViewer::Viewer* viewer1 = osgObj->getOsgViewer();
    while (!viewer1->done())
    {
        osgObj->PreFrameUpdate();
        viewer1->frame();
        osgObj->PostFrameUpdate();
    }

    _endthread();
}

osgViewer::Viewer* COSGObject::getOsgViewer()
{
    return mViewer;
}