osg create shape

Posted 2022-02-05 herd

osg::ref_ptr<osg::Node> OSG_Qt_::createSimple()

    osg::ref_ptr<osg::Geode> geode = new osg::Geode;
    osg::ref_ptr<osg::Geometry> geometry = new osg::Geometry;

    //申请顶点
    osg::ref_ptr<osg::Vec3Array> coords = new osg::Vec3Array;
    //申请颜色
    osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array;
    //申请法向量
    osg::ref_ptr<osg::Vec3Array> norms = new osg::Vec3Array;

    //设置顶点关联方式
    geometry->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::Mode::QUADS,0,4));

    coords->push_back(osg::Vec3(-10.0,0.0,-10.0));
    coords->push_back(osg::Vec3(10.0, 0.0, -10.0));
    coords->push_back(osg::Vec3(10.0, 0.0, 10.0));
    coords->push_back(osg::Vec3(-10.0, 0.0, 10.0));

    //颜色赋值
    colors->push_back(osg::Vec4f(1.0,0.0,0.0,1.0));
    colors->push_back(osg::Vec4f(0.0, 1.0, 0.0, 1.0));
    colors->push_back(osg::Vec4f(0.0, 0.0, 1.0, 1.0));
    colors->push_back(osg::Vec4f(1.0, 1.0, 0.0, 1.0));

    //法向量赋值
    norms->push_back(osg::Vec3(0.0,-1.0,0.0));


    //设置顶点
    geometry->setVertexArray(coords.get());
    //设置颜色
    geometry->setColorArray(colors.get());
    //颜色绑定方式
    geometry->setColorBinding(osg::Geometry::AttributeBinding::BIND_PER_VERTEX);
    //设置法向量
    geometry->setNormalArray(norms.get());
    //法向量绑定
    geometry->setNormalBinding(osg::Geometry::AttributeBinding::BIND_OVERALL);

    geode->addDrawable(geometry.get());
    return geode;