了解OSG节点选择

#include <osgViewer/Viewer>
#include <osgDB/ReadFile>
#include <osgGA/GUIEventHandler>

class nodePick :public osgGA::GUIEventHandler
{
	virtual bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa)
	{
		osgViewer::Viewer *viewer = dynamic_cast<osgViewer::Viewer*> (&aa);
		switch (ea.getEventType())
		{
		case osgGA::GUIEventAdapter::PUSH:
		{
			osgUtil::LineSegmentIntersector::Intersections intersections;
			osg::ref_ptr<osg::Node> node = new osg::Node;
			if (viewer->computeIntersections(ea.getX(), ea.getY(), intersections))
			{
				//得到选择的节点
				osgUtil::LineSegmentIntersector::Intersection intersection = *intersections.begin();
				osg::NodePath& nodePath = intersection.nodePath;
				node = nodePath.back();

				//点击节点透明
				node->setNodeMask(0);
			}
		}
		default:
			return false;
		}
	}
};

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