Creates a link between two positions that [NavigationServer2D] can route agents through. Creates a link between two positions that [NavigationServer2D] can route agents through. Links can be used to express navigation methods that aren't just traveling along the surface of the navigation mesh, like zip-lines, teleporters, or jumping across gaps. $DOCS_URL/tutorials/navigation/navigation_using_navigationlinks.html Returns whether or not the specified layer of the [member navigation_layers] bitmask is enabled, given a [code]layer_number[/code] between 1 and 32. Based on [code]value[/code], enables or disables the specified layer in the [member navigation_layers] bitmask, given a [code]layer_number[/code] between 1 and 32. Whether this link can be traveled in both directions or only from [member start_position] to [member end_position]. Whether this link is currently active. If [code]false[/code], [method NavigationServer2D.map_get_path] will ignore this link. Ending position of the link. This position will search out the nearest polygon in the navigation mesh to attach to. The distance the link will search is controlled by [method NavigationServer2D.map_set_link_connection_radius]. When pathfinding enters this link from another regions navigation mesh the [code]enter_cost[/code] value is added to the path distance for determining the shortest path. A bitfield determining all navigation layers the link belongs to. These navigation layers will be checked when requesting a path with [method NavigationServer2D.map_get_path]. Starting position of the link. This position will search out the nearest polygon in the navigation mesh to attach to. The distance the link will search is controlled by [method NavigationServer2D.map_set_link_connection_radius]. When pathfinding moves along the link the traveled distance is multiplied with [code]travel_cost[/code] for determining the shortest path.