osg 对象选择
/////////////////////////////////////框选//////////////////////////////////////
class BoxPicker : public osgGA::GUIEventHandler
{
public:
BoxPicker()
{
x=0.0f;
y=0.0f;
OK= false;
}
osg::observer_ptr<osg::Geometry> geometry;
virtual bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa)
{
bool doit = false;
osgViewer::Viewer* viewer = dynamic_cast<osgViewer::Viewer*>(&aa);
if (!viewer)
{
return false;
}
if(ea.getEventType() == osgGA::GUIEventAdapter::PUSH)
{
x = ea.getXnormalized();
y = ea.getYnormalized();
x_pick = ea.getX();
y_pick = ea.getY();
OK = true;
}
if (ea.getEventType() == osgGA::GUIEventAdapter::DRAG)
{
if (OK)
{
float end_x = ea.getXnormalized();
float end_y = ea.getYnormalized();
if (geometry.valid())
{
osg::Vec3Array* vertex = new osg::Vec3Array(4);
(*vertex)[0]=osg::Vec3(x,0,y);
(*vertex)[1]=osg::Vec3(x,0,end_y);
(*vertex)[2]=osg::Vec3(end_x,0,end_y);
(*vertex)[3]=osg::Vec3(end_x,0,y);
geometry->setVertexArray(vertex);
geometry->dirtyDisplayList();
//std::cout<<x<<" "<<y<<" "<<end_x<<" "<<end_y<<std::endl;
}
if (ea.getModKeyMask()&osgGA::GUIEventAdapter::MODKEY_LEFT_SHIFT)
{
doit = true;
}
}
}
if (ea.getEventType() == osgGA::GUIEventAdapter::RELEASE)
{
OK=false;
float pick_x = ea.getX();
float pick_y = ea.getY();
float xMin,xMax,yMin,yMax;
xMin=osg::minimum(x_pick, pick_x);
xMax=osg::maximum(x_pick, pick_x);
yMin=osg::minimum(y_pick, pick_y);
yMax=osg::maximum(y_pick, pick_y);
osg::ref_ptr<osgUtil::PolytopeIntersector> intersector =
new osgUtil::PolytopeIntersector(osgUtil::Intersector::WINDOW, xMin, yMin, xMax, yMax);
osgUtil::IntersectionVisitor iv( intersector.get() );
viewer->getCamera()->accept( iv );
if ( intersector->containsIntersections() )
{
std::cout<<"OK"<<std::endl;
/*
for(osgUtil::PolytopeIntersector::Intersections::iterator
hitr = intersector->getIntersections().begin();
hitr != intersector->getIntersections().end();
++hitr)
{
osg::NodePath np = hitr->nodePath;
for (osg::NodePath::iterator itr = np.begin(); itr != np.end(); itr++)
{
if (!(*itr)->getName().empty())
{
std::cout<<(*itr)->getName()<<std::endl;
}
}
break;
}
*/
}
if (geometry.valid())
{
osg::Vec3Array* vertex = new osg::Vec3Array(4);
(*vertex)[0]=osg::Vec3(0,0,0);
(*vertex)[1]=osg::Vec3(0,0,0);
(*vertex)[2]=osg::Vec3(0,0,0);
(*vertex)[3]=osg::Vec3(0,0,0);
geometry->setVertexArray(vertex);
geometry->dirtyDisplayList();
}
}
return doit;
}
float x,y;
float x_pick, y_pick;
bool OK;
};
int _tmain(int argc, char* argv[])
{
osg::ArgumentParser argument(&argc,argv);
osg::Node* model1 = osgDB::readNodeFile("axes.osgt");
model1->setName("COW1");
osg::MatrixTransform* mt1 = new osg::MatrixTransform;
mt1->setMatrix(osg::Matrix::translate(osg::Vec3(10,0,0)));
mt1->addChild(model1);
osg::Node* model2 = osgDB::readNodeFile("axes.osgt");
model2->setName("COW2");
osgViewer::Viewer viewer;
osg::ref_ptr<BoxPicker> picker = new BoxPicker;
viewer.addEventHandler(picker.get());
osg::ref_ptr<osg::Geometry> geo = new osg::Geometry;
geo->setDataVariance(osg::Object::DYNAMIC);
geo->setUseDisplayList(false);
osg::Vec3Array* vertex = new osg::Vec3Array(4);
(*vertex)[0] = osg::Vec3(-0.5, 0.0, -0.5);
(*vertex)[1] = osg::Vec3(0.5, 0.0, -0.5);
(*vertex)[2] = osg::Vec3(0.5, 0.0, 0.5);
(*vertex)[3] = osg::Vec3(-0.5, 0.0, 0.5);
geo->setVertexArray(vertex);
osg::Vec4Array* colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(1.0,1.0,0.0,1.0));
geo->setColorArray(colors);
geo->setColorBinding(osg::Geometry::BIND_OVERALL);
osg::Vec3Array* normal = new osg::Vec3Array(1);
(*normal)[0]=osg::Vec3(0,-1,0);
geo->setNormalArray(normal);
geo->setNormalBinding(osg::Geometry::BIND_OVERALL);
osg::ref_ptr<osg::DrawArrays> pri = new osg::DrawArrays(osg::PrimitiveSet::LINE_LOOP,0,4);
geo->addPrimitiveSet(pri.get());
osg::ref_ptr<osg::PolygonMode> polyMode = new osg::PolygonMode;
polyMode->setMode(osg::PolygonMode::FRONT_AND_BACK, osg::PolygonMode::LINE);
geo->getOrCreateStateSet()->setAttributeAndModes(polyMode.get());
geo->getOrCreateStateSet()->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
picker->geometry = geo;
osg::Camera* camera = new osg::Camera;
camera->setProjectionMatrix(osg::Matrix::ortho2D(-1.0,1.0,-1.0,1.0));
camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
camera->setViewMatrixAsLookAt(osg::Vec3(0,-1,0), osg::Vec3(0,0,0), osg::Vec3(0,0,1));
camera->setClearMask(GL_DEPTH_BUFFER_BIT);
camera->setRenderOrder(osg::Camera::POST_RENDER);
camera->setAllowEventFocus(false);
osg::ref_ptr<osg::Geode> geode = new osg::Geode;
geode->addDrawable(geo.get());
camera->addChild(geode.get());
osg::ref_ptr<osg::Group> root = new osg::Group;
root->addChild(camera);
root->addChild(mt1);
root->addChild(model2);
viewer.setSceneData(root.get());
viewer.setCameraManipulator(new osgGA::OrbitManipulator);
viewer.run();
return 0;
}
////////////////////////////////////点选////////////////////////////////////
osgViewer::Viewer* viewer;
float x;
float y;
//线段和场景的相交情况
osgUtil::LineSegmentIntersector::Intersections intersections;
viewer->computeIntersections(x,y,intersections);