billboard render in 2d with terrain data

1. A concise explanation of the problem you're experiencing.

    Billboard only render once when map init in 2d with terrain data. Billboards added later won't render unless manually zoom in/out.Adding billboard works fine when map is in 2d with no terrain data or 3d.

2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.

var bc = viewer.scene.primitives.add(new Cesium.BillboardCollection({
    scene: viewer.scene
}));

bc.add({
    position:Cesium.Cartesian3.fromDegrees(longitude,latitude);
    image: url/to/image
    heightReference: Cesium.HeightReference.CLAMP_TO_GROUND
});

// code above works fine when excute when map init.
// it will creat a billboard object but won't be rendered on map after map
// initialized

3. Context. Why do you need to do this? We might know a better way to accomplish your goal.

Is there a way force billboard added after map initialized to render without zoom in/out?

4. The Cesium version you're using, your operating system and browser.

Cesium 1.38
win10
chrome 61

Hi there,

Here’s an example of adding billboards to a collection at runtime in 2D.

Thanks,

Gabby

Not exactly what i expected but thanks anyway.
The problem only ocurred when map init in 2d with terrainProvider and billboard added with HeightReference.CLAMP_TO_GROUND,to be exact.

Ok, I see. We’re aware of this, and we’re tracking it in this GitHub issue. Feel free to add any additional info there, or submit a fix if you have the bandwidth. We’d be happy to provide guidance.

Thanks, sorry for the miscommunication.

Gabby