drag and drop CZML entity

CesiumJS
1

I cannot figure how to 'drag and drop' the position of an entity loaded by czmlDataSource. This Sandcastle code seems on the cusp of success... but as you see I cannot figure how to <<addSample>> a point without a dateTime.

---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
var czml = [{
    "id" : "document",
    "name" : "CZML Point",
    "version" : "1.0"
}, {
    "id" : "point 1",
    "name": "point",
    "position" : {
        "cartographicDegrees" : [-111.0, 40.0, 0]
    },
    "point": {
        "color": {
            "rgba": [255, 255, 255, 255]
        },
        "outlineColor": {
            "rgba": [255, 0, 0, 255]
        },
        "outlineWidth" : 4,
        "pixelSize": 20
    }
}];

var viewer = new Cesium.Viewer('cesiumContainer');
var unitDataSource = new Cesium.CzmlDataSource;
unitDataSource.load(czml);
viewer.dataSources.add(unitDataSource);
viewer.zoomTo(unitDataSource);

var entityId;
var dragging = undefined;
var editPointHandler = new Cesium.ScreenSpaceEventHandler(viewer.canvas);

editPointHandler.setInputAction(function(click) {
    var pickedObject = viewer.scene.pick(click.position);
    if (Cesium.defined(pickedObject) && pickedObject.id.name === 'point') {
    entityId = pickedObject.id.id;
    dragging = pickedObject;
        viewer.scene.screenSpaceCameraController.enableRotate = false;
    }
}, Cesium.ScreenSpaceEventType.LEFT_DOWN);

editPointHandler.setInputAction(function() {
    if (Cesium.defined(dragging)) {
        dragging = undefined;
        viewer.scene.screenSpaceCameraController.enableRotate = true;
    }
}, Cesium.ScreenSpaceEventType.LEFT_UP);

editPointHandler.setInputAction(function(movement) {
    var editLat, editLon;
    var editPosition = viewer.camera.pickEllipsoid(movement.endPosition);
    if (!Cesium.defined(editPosition) || !dragging) {
        return;
    }

    var positionCartographic = Cesium.Ellipsoid.WGS84.cartesianToCartographic(editPosition);
  editLon = Cesium.Math.toDegrees(positionCartographic.longitude);
  editLat = Cesium.Math.toDegrees(positionCartographic.latitude);

  var entity = unitDataSource.entities.getById(entityId);
  entity.position.addSample(Cesium.JulianDate.fromIso8601(entityId), Cesium.Cartesian3.fromDegrees(editLon,editLat));

}, Cesium.ScreenSpaceEventType.MOUSE_MOVE);

---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----

3. Context. Why do you need to do this? We might know a better way to accomplish your goal - We want to edit the location of models interactively. The data is time-based data loaded as a czmlDataSource. The current method of typing in coordinate data is so 1980s.

2

As you suspected you are close. You need to set the value of the ConstantPositionProperty of the entity.

entity.position.setValue(Cesium.Cartesian3.fromDegrees(editLon, editLat));

``

Scott