Spacefiller

This article is about cellular automata. For tessellations of Euclidean space by polyhedra, see Honeycomb (geometry). For fractal curves that cover a two-dimensional region, see Space-filling curve.

File:Spacefiller animation.gif

Spacefiller showing the moving leading edges and the stationary still life it leaves.

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The cell count per generation of the above spacefiller pattern clearly showing its quadratic growth.

In Conway's Game of Life and related cellular automata, a spacefiller is a pattern that spreads out indefinitely, eventually filling the entire space with a still life pattern. It typically consists of three components: stretchers that resemble spaceships at the four corners of the pattern, a growing boundary region along the edges of the pattern, and the still life in the interior pattern.

It resembles a breeder in that both types of patterns have a quadratic growth rate in their numbers of live cells, and in both having a three-component architecture. However, in a breeder the moving part of the breeder (corresponding to the stretcher) leaves behind a fixed sequence of glider guns which fill space with gliders, moving objects (gliders or spaceships) rather than still life patterns. With a spacefiller, unlike a breeder, every point in the space eventually becomes part of the space-filling still life pattern.