We illustrate algorithms for dispersing a swarm of primitive robots in a two-dimensional unknown environment R. Each robot in the swarm is equipped with a simple sensor that is able to view neighboring locations to determine the presence of other robots or obstacles. At each time step, based on the sensor readings, a robot may decide to take a step to a neighboring point. The objective is to minimize the makespan, that is, the time to fill R with robots. Here, we consider environments that are discrete, composed of unit squares (pixels) that are induced by the integer grid within a polygonal domain R. There is at most one robot per pixel and robots move horizontally or vertically at unit speed. Robots enter R by means of k ≥ 1 door pixels on the boundary of R, each of which acts as an infinite source of robots. The domain R is filled when there is a robot in each pixel. Robots are primitive finite automata, only having local communication, local sensors, and a constant-sized memory. These local autonomous agents are not centrally controlled, yet are expected to perform the global task of dispersing. In a recent paper [2], we provide a variety of theoretical results, including: