WireFrame설정

#include <osg/PolygonMode>

...
osg::Switch* mRoot = new osg::Switch;

//Wire Frame Test
osg::ref_ptr<osg::Node> cow = osgDB::readNodeFile("model/cow.osg");//mesh loading
mRoot->addChild(cow, true);//switch node

osg::StateSet* state = cow->getOrCreateStateSet();//Get State
//Create Attribute
osg::PolygonMode* pt = new osg::PolygonMode(osg::PolygonMode::FRONT_AND_BACK,
                                                                      osg::PolygonMode::LINE);
//set child Attribute.
state->setAttributeAndModes(pt.get(), osg::StateAttribute::ON || osg::StateAttribute::OVERRIDE);