#include<Windows.h>
#include<osg/Node>
#include<osg/Geode>
#include<osg/Group>
#include <osg/Geometry>
#include<osgUtil/Optimizer>
#include <cmath>
#include<iostream>
#include<osgViewer/Viewer>
#include<osgDB/ReadFile>
#include<osgDB/WriteFile>
#define PI 3.1415926
osg::Vec3 pointSet[100000];
#define N 301
int main()
{
float phi = (sqrt(5) + 1) / 2 - 1;
//float phi = 0.617;
float xTemp,yTemp,zTemp;
for (int i=1;i<= N;i++)
{
zTemp = (2*(float)i-1)/ N -1;
xTemp = sqrt(1 - zTemp*zTemp)*cos(2 * PI*(float)i*phi);
yTemp = sqrt(1 - zTemp*zTemp)*sin(2 * PI*(float)i*phi);
pointSet[i - 1].set(xTemp, yTemp, zTemp);
pointSet[i - 1].normalize();
}
std::ofstream outf;
outf.open("shotEye.txt", std::ios::trunc);
for (int i = 0; i < N; i++)
{
outf << pointSet[i]._v[0] << " " << pointSet[i]._v[1] << " " << pointSet[i]._v[2] << std::endl;
}
outf.close();
osg::ref_ptr<osg::Vec3Array> vertex = new osg::Vec3Array;
osg::ref_ptr<osg::Vec3Array> normal = new osg::Vec3Array;
for (int i=0;i<N;i++)
{
vertex->push_back(pointSet[i]);
normal->push_back(pointSet[i]);
}
osg::ref_ptr<osg::Vec4Array> colorArray = new osg::Vec4Array;
colorArray->push_back(osg::Vec4(1.0f, 0.0f, 0.0f, 1.0f));
osg::ref_ptr<osgViewer::Viewer> viewer = new osgViewer::Viewer;
osg::ref_ptr<osg::Group> node = new osg::Group;
osg::ref_ptr<osg::Geode> geode = new osg::Geode;
osg::ref_ptr<osg::Geometry> geometry = new osg::Geometry;
geometry->setVertexArray(vertex.get());
geometry->setNormalArray(normal.get());
geometry->setColorArray(colorArray.get());
geometry->setColorBinding(osg::Geometry::BIND_OVERALL);
geometry->setNormalBinding(osg::Geometry::BIND_PER_VERTEX);
geometry->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POINTS, 0, N));
geode->addDrawable(geometry);
node->addChild(geode);
osgUtil::Optimizer optimizer;
optimizer.optimize(node.get());
viewer->setSceneData(node.get());
viewer->realize();
viewer->run();
return 0;
}
效果图：
实现原理来自：