Position of Billboard on a building/3D Tile or Extrusion/Lollipopping


I have a billboard, which I would like display over/at a building.

position: Cesium.Cartesian3.fromRadians(latlon.longitude,latlon.latitude),
billboard: {
image: “./whiteShapes.png”,
imageSubRegion: new Cesium.BoundingRectangle(67, 80, 14, 14),
color: new Cesium.Color(0.5, 0.9, 1.0, 1.0),
scale: 2.0,
verticalOrigin : Cesium.VerticalOrigin.BOTTOM,
heightReference: Cesium.HeightReference.CLAMP_TO_GROUND,
disableDepthTestDistance: Number.POSITIVE_INFINITY,

This marker now changes the position, if I navigate around the building, because of the heightReference → it sits on the “walls” and on the other side because I disabled the DepthTest it is seen from everywhere.

Is there a possibility to get/pick the height of the buildings (3D-Tiles) and set the billboard on top ? Do I need a position callback (? I’m using typescript, error is known) ?

Or has anyone experience with extrusion and lollipopping ?

“In many cases, billboarded or cubed symbols are raised above the ground surface using a marker post, a technique sometimes called “lollipopping”. The user can set an arbitrary height above ground surface and drop down lines connect the symbol to its ground location.”