This paper describes a model of three-dimensional cellular automata allowing to simulate different phenomena in the fields of computer graphics or image processing. Our method allows to combine them together in order to produce complex effects such as automatic texturing, surface imperfections, or biological retina multi-layer cellular behaviours. Our cellular automaton model is defined as a network of connected cells arranged in a natural and dynamic way, which affords multi-behavior capabilities. Based on cheap and widespread computing systems, real-time performance can be reached for simulations involving up to a hundred thousand cells. The efficiency of such an approach is illustrated by a set of CA related to computer graphics –e.g. erosion, sedimentation, or vegetal growing processes– and image analysis –e.g. retina simulation.