图像与OSG旋转消失(Image is disappearing with rotation in

我有一个简单OSG程序，这使得一个x，y轴和randomises该轴的内部的点。其意图是，这将导致上使激光扫描数据的3D浏览器。（我知道它已经做过，但我们需要的是超轻型）。下面是代码：

#include <osg/Node>
#include <osg/Group>
#include <osg/Geode>
#include <osg/Geometry>
#include <osg/Texture2D>
#include <osgDB/ReadFile> 
#include <osgViewer/Viewer>
#include <osg/PositionAttitudeTransform>
#include <osgGA/TrackballManipulator>
#include <time.h>
#include <cstdlib>

void addAxis(osg::ref_ptr<osg::Group> root) {


//ADD Y-Axis
osg::ref_ptr<osg::Geode> lineGeode = new osg::Geode();
osg::ref_ptr<osg::Geometry> yAxis = new osg::Geometry(), xAxis = new osg::Geometry();

lineGeode->addDrawable(yAxis);
lineGeode->addDrawable(xAxis);
root->addChild(lineGeode);


osg::ref_ptr<osg::Vec3Array> lineVertices = new osg::Vec3Array;
lineVertices->push_back( osg::Vec3( 0, 0, 0) );
lineVertices->push_back( osg::Vec3(0, 10, 0) );


yAxis->setVertexArray( lineVertices );

osg::ref_ptr<osg::DrawElementsUInt> lineBase =
    new osg::DrawElementsUInt(osg::PrimitiveSet::LINES, 0);
lineBase->push_back(1);
lineBase->push_back(0);
yAxis->addPrimitiveSet(lineBase);


osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(1.0f, 0.0f, 0.0f, 1.0f) ); //index 0 red
yAxis->setColorArray(colors);
yAxis->setColorBinding(osg::Geometry::BIND_PER_PRIMITIVE);



//ADD X Axis
lineVertices = new osg::Vec3Array;
lineVertices->push_back( osg::Vec3( 0, 0, 0) );
lineVertices->push_back( osg::Vec3(10, 0, 0) );


xAxis->setVertexArray( lineVertices );

lineBase =
    new osg::DrawElementsUInt(osg::PrimitiveSet::LINES, 0);
lineBase->push_back(1);
lineBase->push_back(0);
xAxis->addPrimitiveSet(lineBase);


colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(0.0f, 0.0f, 0.0f, 1.0f) ); //index 0 red
xAxis->setColorArray(colors);
xAxis->setColorBinding(osg::Geometry::BIND_PER_PRIMITIVE);

}

void addPoint(osg::ref_ptr<osg::Group> root, std::vector<double> pointIn) {
 osg::ref_ptr<osg::Geode> pointGeode = new osg::Geode();
osg::ref_ptr<osg::Geometry> pointGeometry = new osg::Geometry();



pointGeode->addDrawable(pointGeometry);
root->addChild(pointGeode);

osg::ref_ptr<osg::Vec3Array> point = new osg::Vec3Array;
point->push_back( osg::Vec3( pointIn[0], pointIn[1], pointIn[2]) );

pointGeometry->setVertexArray( point );

osg::ref_ptr<osg::DrawElementsUInt> points =
    new osg::DrawElementsUInt(osg::PrimitiveSet::POINTS, 0);

points->push_back(0);
points->push_back(2);
points->push_back(1);
pointGeometry->addPrimitiveSet(points);


osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(1.0f, 1.0f, 1.0f, 1.0f) ); 

 pointGeometry->setColorArray(colors);
    pointGeometry->setColorBinding(osg::Geometry::BIND_PER_PRIMITIVE);
}


int main()
{
osgViewer::Viewer viewer;
osg::ref_ptr<osg::Group> root = new osg::Group();

addAxis(root);


std::vector<double> point;
for (int i = 0; i < 3; i++)
   point.push_back(0);
srand(time(NULL));

root->getOrCreateStateSet()->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
viewer.setSceneData( root );

viewer.setCameraManipulator(new osgGA::TrackballManipulator());
viewer.realize();
int count = 0;
while( !viewer.done() )
{
    if (count == 200) {
    point[0] = (double)rand()*10.0/(double)INT_MAX;
    point[1] = (double)rand()*10.0/(double)INT_MAX;
    count = 0;
    }
    count++;
    addPoint(root, point);

    viewer.frame();



}

return 0;
}

此代码的工作，就会产生一个10单元长的x / y轴并开始产生该轴的内部的随机点。然而，问题是，当我在OSG观察者旋转图像的整体形象往往消失。有时候，它可以通过转回到你开始的地方，但更多的时候它就会永远消失带回。

有没有人有关于为什么会这样的想法？

我想通了，在这种情况下，原因是点更新太快。这导致与渲染的点进来的快速图像可视化非常困难。