7.1 Introduction
In addition to the usual 3D and physics-based simulation modes, Webots offers a 2D simulation mode called Fast2D. The Fast2D mode enables very fast simulation for worlds that require only two-dimensional (2D) computations. Many simulations are carried out on a 2D area using wheeled robots such as AliceTM or KheperaTM; in such simulations the height and elevation of the objects are generally irrelevant, therefore the overhead of 3D computations can be avoided by using Fast2D. The Fast2D plugin is designed for situations where the speed of a simulation is more important than its realism, as in evolutionary robotics or swarm intelligence, for example.