TimeGUI example (with WMS-T)

timegui.cpp

/** PASTE ME OVER osgearth_imgui.cpp **/

#include <osgEarth/ImGui/ImGui>
#include <osgEarth/EarthManipulator>
#include <osgEarth/ImageLayer>

#include <osg/ImageSequence>
#include <osgDB/ReadFile>
#include <osgViewer/Viewer>

using namespace osgEarth;
using namespace osgEarth::Util;

struct App
{
    DateTime _time;
};

struct TimeGUI : public GUI::BaseGUI
{
    App& _app;
    float _time;
    DateTime _start, _end;
    bool _initialized;
    osg::observer_ptr<MapNode> _mapNode;

    TimeGUI(App& app) : BaseGUI("Time Control"), 
        _app(app), _time(0.0f), _start(UINT_MAX), _end(0), _initialized(false) { }

    void draw(osg::RenderInfo& ri) override
    {
        if (!isVisible()) return;
        if (!findNode(_mapNode, ri)) return;

        if (!_initialized)
        {
            LayerVector layers;
            _mapNode->getMap()->getLayers(layers);
            for (auto& layer : layers) {
                DateTimeExtent ex = layer->getDateTimeExtent();
                if (ex.valid()) {
                    if (ex.getStart() < _start)
                        _start = ex.getStart();
                    if (ex.getEnd() > _end)
                        _end = ex.getEnd();
                }
            }
            _initialized = true;
        }

        ImGui::Begin(name(), visible());
        if (_end > _start)
        {
            if (ImGui::SliderFloat("Offset (s)", &_time, 0.0f, (float)(_end.asTimeStamp()-_start.asTimeStamp())))
            {
                _app._time = DateTime(_time+_start.asTimeStamp());
            }
            ImGui::Text("%s", DateTime(_time + _start.asTimeStamp()).asISO8601().c_str());
        }
        else
        {
            ImGui::Text("No time extents found in map.");
        }
        ImGui::End();
    }
};

int
main(int argc, char** argv)
{
    osgEarth::initialize();

    App app;

    osg::ArgumentParser arguments(&argc, argv);
    osgViewer::Viewer viewer(arguments);
    viewer.setThreadingModel(viewer.SingleThreaded);
    viewer.setCameraManipulator(new EarthManipulator(arguments));
    viewer.setRealizeOperation(new GUI::ApplicationGUI::RealizeOperation);

    auto gui = new GUI::ApplicationGUI(arguments, true);
    gui->add(new TimeGUI(app), true);
    viewer.getEventHandlers().push_front(gui);

    auto node = MapNodeHelper().loadWithoutControls(arguments, &viewer);
    viewer.setSceneData(node);
    viewer.realize();
    while (!viewer.done()) {
        viewer.frame(app._time.asTimeStamp());
    }
    return 0;
}