You're looking at the edge of one of the four curved panels of Push/Pull (2009). When you move towards the face of the panel and launch the interaction, the red light becomes your agent. By moving your agent close to the two yellow agents, you can "greet" them (their positions are driven by the system). A second phase with a bigger population of agents ensues.
Two sequences are shown here, as well as the cellular automaton that ends each. The first time through, the red agent keeps its shape and passes it on to the yellow agents. In the second round, yellow agents greet first and consequently pass their shape to your red agent. You can play a game with the system by trying to keep your shape and pass it on.