Indication
constructor(stroke: String? = "#4965E7", radiusMeter: Double? = 2.0, sourceColor: String? = "#f00", destColor: String? = "#2424b1", opacity: Double? = 1.0, iconSource: String? = null, iconDestination: String? = null, followZoom: Boolean? = false, iconVAlign: String? = "bottom", iconHAlign: String? = "right")