This applet displays a reaction-diffusion system. Begin exploring by using the "Preset" choice at the bottom - and the "Restart" button below it - to see some of the possible configurations. Configurable parameters include a number of manual colour-map controls (on the left) - and six main parameters of the reaction-diffusion system (on the right). Take care if using the other controls on the right. They are usually very sensitive. The model is a cellular automaton, based on the von-Neumann neighbourhood. It is based on the Gray-Scott model, and was taken from John E. Pearson's Complex Patterns in a Simple System - Science, 261, 189, 9 July 1993. More details about the type of system used can be found at the [Xmorphia web site]. Toroidial boundary constraints are appled, so the images will tesselate seamlessly. Optionally, a bumpmap technique is employed to give the images a sense of depth. Geometric note While reaction-diffusion systems generally attempt to obscure the underlying cellular lattice, it still emerges under some configurations which magify chaotic effects from scall scales. Also, the "saturated" state in the automaton is often a chequer-board pattern. For these reasons, it seems that reaction-diffusion systems on a hexagonal grid would be interesting to explore (there is no equivalent to the chequer-board pattern on the [honeycomb neighbourhood]).