2D Obstacle used in navigation for collision avoidance. 2D Obstacle used in navigation for collision avoidance. The obstacle needs navigation data to work correctly. [NavigationObstacle2D] is physics safe. Returns the [RID] of this obstacle on the [NavigationServer2D]. Enables radius estimation algorithm which uses parent's collision shapes to determine the obstacle radius. The radius of the agent. Used only if [member estimate_radius] is set to false.