PixelZoo is a turn-based multiplayer game for mobile phones and tablets. At its core is an engine for games based on two-dimensional CA (cellular automata) and A-life (artificial life). It's designed to be robust enough that players can design & upload their own CA programs without crashing the system, flexible enough to explore a biologically interesting range of CAs (more on that in a moment), and fast enough that it's aesthetically pretty and fun to play with on a cellphone. It's intended eventually to have clear game mechanics and goals (e.g. capture-the-flag) although at present it's just a sandbox. So, why CAs? We often hear that current games "do physics well", but CAs can model aspects of physics (and other sciences) that have been less frequently seen in games. Examples include the collective behavior of crowds, the properties of fluids and gases, ecological food webs, and many other systems where emergent properties arise from large numbers of agents interacting via simple local rules. Then there is A-life (the study of self-replicating computer programs), where much of the key research is CA-based. I will survey a bunch of CA models from different branches of science that I think are under-explored as game mechanics (and hopefully fun), with demonstrations using PixelZoo. I'll also review various existing game mechanics (e.g. Lemmings, FarmVille, war games, Sim games...) that already map reasonably well onto CAs. I'll present a new PixelZoo-based simulation of DNA & RNA molecules that I've developed, as part of an ongoing effort to make A-life less "abstract" and bring it closer to our biological reality of self-replicating molecules and cells. PixelZoo includes a high-level language for designing CA agent programs, a user interface for interactively "painting" on shared CA spaces, and a client-server architecture for maintaining persistent shared worlds. I'll briefly describe these and other aspects of PixelZoo's design.
Ian Holmes is a former indie game developer turned associate professor of Bioengineering at UC Berkeley. In biology, he is interested in modern-day echoes of the "RNA world" hypothesis for the origins of life, interpretations of sequencing data for microbial ecology, evolutionary methods in "synthetic biology", and the development of web infrastructure for genome annotation and design. In computer gaming and ALife, he is interested in applications of CAs to model the "primordial soup", and ways to popularize this approach, scientifically and artistically.