unable to select a label

[AhmedAredah]

I have an application that features the OSGEarth, it adds multiple labels to the earth model and the user is expected to select multiple of these labels by clicking. However, I am unable to select any label and the pick function does not get called. I would appreciate any help on that. I tried to follow the osgEarth_pick.cpp

here is the relative chunk of code that I believe is related:

// helping class definition
    void addSeaPort()
    {

        if (!_mapNode.valid())
        {
            qDebug() << "MapNode is not valid!";
            return;
        }

        // load sea ports
        QVector<std::shared_ptr<SeaPort>> ports =
            OptimizedNetwork::loadFirstAvailableSeaPorts();

        // hold sea ports as a map of countries
        std::unordered_map<QString,
                           QVector<std::shared_ptr<SeaPort>>>
            portsByCountry;

        // Style our labels:
        osgEarth::Style labelStyle;
        labelStyle.getOrCreate<osgEarth::TextSymbol>()->alignment() =
            osgEarth::TextSymbol::ALIGN_CENTER_CENTER;
        labelStyle.getOrCreate<osgEarth::TextSymbol>()->fill()->color() =
            osgEarth::Color::Black;
        labelStyle.getOrCreate<osgEarth::TextSymbol>()->halo() =
            osgEarth::Color("#5f5f5f");

        osgEarth::Style pointStyle;
        pointStyle.getOrCreate<osgEarth::IconSymbol>()->url()->setLiteral("path/to/icon.png");
        pointStyle.getOrCreate<osgEarth::IconSymbol>()->declutter() = true;


        // Path for icon
        std::string icon =
            Utils::getFirstExistingPathFromList(Defaults::iconPath).toStdString();

        // Style for place node marker
        osgEarth::Style pm;
        pm.getOrCreate<osgEarth::IconSymbol>()->url()->setLiteral( icon );
        pm.getOrCreate<osgEarth::IconSymbol>()->declutter() = true;
        // pm.getOrCreate<osgEarth::TextSymbol>()->halo() =
        //     osgEarth::Color("#5f5f5f");

        // group ports by country
        for (const auto& port : ports) {
            portsByCountry[port->getCountryName()].push_back(port);
        }

        // hold all ports
        osg::Group* parentGroup = new osg::Group();

        const osgEarth::SpatialReference* geoSRS =
            _mapNode->getMapSRS()->getGeographicSRS();
        // PortClickHandler* clickHandler =
        //     PortClickHandler::getInstance();
        for (const auto& countryPorts : portsByCountry) {
            osg::Group* countryGroup = new osg::Group();
            countryGroup->setName(
                "Country_" +
                countryPorts.second[0]->getCountryName().toStdString());
            for (const auto& port : countryPorts.second) {
                QString labelText = port->getPortName() +
                                    " (" + port->getPortCode() + ")";
                osgEarth::AnnotationNode* iconNode    = 0L;
                osgEarth::PlaceNode* label =
                    new osgEarth::PlaceNode(
                        osgEarth::GeoPoint(
                            geoSRS,
                            port->getPortCoordinate().getLongitude().value(),
                            port->getPortCoordinate().getLatitude().value(), 0,
                            osgEarth::AltitudeMode::ALTMODE_ABSOLUTE),
                        labelText.toStdString(),
                        pm);
                label->setStyle(labelStyle);
                // label->setName("Port_" + port->getPortName().toStdString());
                iconNode = label;

                // osgEarth::Registry::instance()->objectIndex()->tagNode(iconNode, iconNode );
                // osgEarth::Registry::instance()->objectIndex()->setObjectIDAtrribLocation(1);
                // osgEarth::Registry::objectIndex()->tagNode( iconNode, iconNode );

                // clickHandler->addPortNode(label, port);

                countryGroup->addChild(iconNode);
            }
            parentGroup->addChild(countryGroup);
        }
        _mapNode->addChild(parentGroup);

        // clickHandler->setTraversingRoot(parentGroup);
        // printSceneGraph(root);

    }
    
    
    
    // inside main.cpp :
    
        std::cout << "Setting picker view and graph." << std::endl;
        picker->setView(getOsgViewer());
        picker->setGraph(preloadedMapRoot.get());   // preloadedMapRoot.get() is a osg::ref_ptr<osg::Group>
        preloadedMapRoot->addChild(picker);
        std::cout << "Picker added to scene graph." << std::endl;

        ObjectIDPicker::Function pick = [&](ObjectID id)
        {
            std::cout << id << "here!\n";
            if (id > 0)
            {
                std::cout << "Inside: " << id << " --  ";

                // Got a pick:
                FeatureIndex* index = Registry::objectIndex()->get<FeatureIndex>(id).get();
                std::cout << "BLA: " << index;
                Feature* feature = index ? index->getFeature(id) : nullptr;
                _pickedAnno = Registry::objectIndex()->get<AnnotationNode>(id).get();
                if (_pickedAnno) {
                    std::cout << "Label: " << _pickedAnno->getName() << " : " << id;
                }
                else {
                    std::cout << "Picked annotation is null.";
                }
            }
            else
            {
                // No pick:
                _pickedAnno = nullptr;
            }
        };

        picker->onClick(pick);

[gwaldron]

You do need to tag your annotation to make it clickable. (You commented this out.)
Here's a simple code snippet that works:

auto anno = new PlaceNode();
anno->setText("Hello, World!");
anno->setPosition(GeoPoint(mapnode->getMapSRS(), -122.5, 45.5));
Registry::objectIndex()->tagNode(anno, anno);
mapnode->addChild(anno);

auto picker = new ObjectIDPicker();
picker->setView(&viewer);
picker->setGraph(mapnode);
mapnode->addChild(picker);

picker->onClick([&](const ObjectID& id)
    {
        if (id != OSGEARTH_OBJECTID_EMPTY)
        {
            auto place = Registry::objectIndex()->get<AnnotationNode>(id);
            if (place)
            {
                std::cout << "Clicked on \"" << place->getText() << "\"" << std::endl;
            }
        }
    });

Hope this helps!

[AhmedAredah]

Thank you. It worked now.