function createRadar(id,far) {
  var options = {
    'viewer': parent.viewer,
    'position': parent.Cesium.Cartesian3.fromDegrees(-120.0, 40.0),
    'id': id,
    'heading': 15,
    'pitch': 0,
    'roll': 0,
    'angle': 360,
    'cone': 90,
    'far': far,
    'near': 5,
    'color': parent.Cesium.Color.RED.withAlpha(0.2),
    'outColor': parent.Cesium.Color.RED.withAlpha(0.7)
  }
  CesiumRadar.createByMousePick(options);
}

function removeRadar(id) {
  CesiumRadar.remove(viewer, id);
}
function clearRadar() {
  CesiumRadar.clear(viewer);
}