Mesh-based navigation and pathfinding node. Provides navigation and pathfinding within a collection of [NavigationMesh]es. These will be automatically collected from child [NavigationMeshInstance] nodes. In addition to basic pathfinding, this class also assists with aligning navigation agents with the meshes they are navigating on. Returns the path between two given points. Points are in local coordinate space. If [code]optimize[/code] is [code]true[/code] (the default), the agent properties associated with each [NavigationMesh] (radius, height, etc.) are considered in the path calculation, otherwise they are ignored. Returns the closest point between the navigation surface and the segment. Returns the point closest to the provided [code]point[/code] on the navigation mesh surface. Returns the normal for the point returned by [method get_closest_point]. Returns the owner region RID for the point returned by [method get_closest_point]. Defines which direction is up. By default, this is [code](0, 1, 0)[/code], which is the world's "up" direction.