Hit-Testing

Relevant Cesium Source

Relevant Google Earth Source (link)

ge.getLayerRoot().enableLayerById(ge.LAYER_TERRAIN, true);
                    ge.getLayerRoot().enableLayerById(ge.LAYER_BUILDINGS, true);

google.earth.addEventListener(ge.getGlobe(), 'click', function(evt) {
                        if (evt.getButton() != 0)
                            return;

// remove old placemarks
                        if (globePlacemark)
                            ge.getFeatures().removeChild(globePlacemark);
                        if (terrainPlacemark)
                            ge.getFeatures().removeChild(terrainPlacemark);
                        if (buildingsPlacemark)
                            ge.getFeatures().removeChild(buildingsPlacemark);

// hit test and create new placemarks
                        var hitTestResult = ge.getView().hitTest(evt.getClientX(), ge.UNITS_PIXELS, evt.getClientY(), ge.UNITS_PIXELS, ge.HIT_TEST_GLOBE);
                        if (hitTestResult) {
                            globePlacemark = makePlacemark(hitTestResult.getLatitude(), hitTestResult.getLongitude(), hitTestResult.getAltitude(), ge.ALTITUDE_ABSOLUTE, 'G');
                            ge.getFeatures().appendChild(globePlacemark);
                        }

hitTestResult = ge.getView().hitTest(evt.getClientX(), ge.UNITS_PIXELS, evt.getClientY(), ge.UNITS_PIXELS, ge.HIT_TEST_TERRAIN);
                        if (hitTestResult) {
                            terrainPlacemark = makePlacemark(hitTestResult.getLatitude(), hitTestResult.getLongitude(), hitTestResult.getAltitude(), ge.ALTITUDE_ABSOLUTE, 'T');
                            ge.getFeatures().appendChild(terrainPlacemark);
                        }

hitTestResult = ge.getView().hitTest(evt.getClientX(), ge.UNITS_PIXELS, evt.getClientY(), ge.UNITS_PIXELS, ge.HIT_TEST_BUILDINGS);
                        if (hitTestResult) {
                            buildingsPlacemark = makePlacemark(hitTestResult.getLatitude(), hitTestResult.getLongitude(), hitTestResult.getAltitude(), ge.ALTITUDE_ABSOLUTE, 'B');
                            ge.getFeatures().appendChild(buildingsPlacemark);
                        }
                    });

function makePlacemark(lat, lng, alt, altMode, iconStr) {
                        var icon = ge.createIcon('');
                        icon.setHref('http://maps.google.com/mapfiles/kml/paddle/' + iconStr + '.png');

var style = ge.createStyle('');
                        style.getIconStyle().setIcon(icon);
                        style.getIconStyle().getHotSpot().set(0.5, ge.UNITS_FRACTION, 0, ge.UNITS_FRACTION);

var pt = ge.createPoint('');
                        pt.set(lat, lng, alt, altMode, false, false);

var pm = ge.createPlacemark('');
                        pm.setGeometry(pt);
                        pm.setStyleSelector(style);

return pm;
                    }