osg入门系列9-一个正方形

#include <osgViewer/Viewer>

#include <osg/Node>

#include <osg/Geode>

#include <osg/Group>

#include <osgDB/ReadFile>

#include <osgDB/WriteFile>

#include <osgUtil/Optimizer>

osg::ref_ptr<osg::Node> createQuad()

{

    osg::ref_ptr<osg::Geode> geode = new osg::Geode();

    osg::ref_ptr<osg::Geometry> geom = new osg::Geometry();

    osg::ref_ptr<osg::Vec3Array> v= new osg::Vec3Array();

    v->push_back(osg::Vec3(0.0f, 0.0f, 0.0f));

    v->push_back(osg::Vec3(1.0f, 0.0f, 0.0f));

    v->push_back(osg::Vec3(1.0f, 0.0f, 1.0f));

    v->push_back(osg::Vec3(0.0f, 0.0f, 1.0f));

    geom->setVertexArray(v.get());

    osg::ref_ptr<osg::Vec2Array> vt = new osg::Vec2Array();

    vt->push_back(osg::Vec2(0.0f, 0.0f));

    vt->push_back(osg::Vec2(1.0f, 0.0f));

    vt->push_back(osg::Vec2(1.0f, 1.0f));

    vt->push_back(osg::Vec2(0.0f, 1.0f));

    geom->setTexCoordArray(0, vt.get());

    osg::ref_ptr<osg::Vec4Array> vc = new osg::Vec4Array();

    vc->push_back(osg::Vec4(1.0f, 0.0f, 0.0f, 1.0f));

    vc->push_back(osg::Vec4(0.0f, 1.0f, 0.0f, 1.0f));

    vc->push_back(osg::Vec4(0.0f, 0.0f, 1.0f, 1.0f));

    vc->push_back(osg::Vec4(1.0f, 1.0f, 0.0f, 1.0f));

    geom->setColorArray(vc.get());

    geom->setColorBinding(osg::Geometry::BIND_PER_VERTEX);

    osg::ref_ptr<osg::Vec3Array> nc = new osg::Vec3Array();

    nc->push_back(osg::Vec3(0.0f, -1.0f, 0.0f));

    geom->setNormalArray(nc.get());

    geom->setNormalBinding(osg::Geometry::BIND_OVERALL);

    geom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS, 0, 4));

    geode->addDrawable(geom.get());

    return geode.get();

}

#include <iostream>

using namespace std;

int main()

{

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

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

    root->addChild(createQuad());

    osgUtil::Optimizer optimizer;

    optimizer.optimize(root.get());

    viewer->setSceneData(root.get());

    viewer->realize();

    viewer->run();

    return 0;

}

-----