Billboard

Billboard {
 addChildren #eventIn MFNode
 removeChildren #eventIn MFNode
 axisOfRotation 0 1 0 #exposedField SFVec3f
 children [] #exposedField MFNode
 bboxCenter 0 0 0 #field MFNode
 bboxSize -1 -1 -1 #field SFVec3f
}