Cellular Automata II

As mentioned before I’ve made a one dimensional Cellular Automata(CA). And although it was intriguing they quickly became very predictive. Actually it was in two dimensions. As the a y-coordinate represented time, but since the states were only depending an the adjacent neighbor’s to the right or left its considered to be one-dimensional.

But they are not as fascinating as CA’s where you expand the neighborhood to include all the eight adjacent cells. That’s called the Moore Neighborhood.

Representing the time dimension. As the intersting part is the evolution of the system, representing time is essential. With a two-dimensional CA it has to be done using animations, and who doesn’t like blinking pixels. This makes CA’s makes even more fun.

In order to decide the state of a cell I look at the Moore neighborhood for every cell on the grid, and count how many neighboring cells are alive. If a cell is alive, then we have to determine whether it survives or dies. If a cell is dead / empty there is the posibility of birth. By defining how many neighbors a cell has to have to survive, and hov many it takes to “give birth” it is possible to run the automata. And this is enough to define a highly complex behavior.

The ubiquitous Conway’s game of life survives if there are 2 or 3 neighbor’s alive and a cell is born if 2 cells are alive, this can be written as : S/B = 23/2. Using a notation like this makes it easy to try out new rules, just adjusting the S/B sets.

I made a small c++ program again using CImg to render these automatons. It’s a rather quick hack, and as such there are plenty off room for optimizing.

But for now it does its job and I don’t intend to develop it further, at least for now. And I think that CIimg might not be the best api for this, I need to look into SDL.

I spent way too much time hacking around to get a nice coloring scheme, and well CImgs intended users are making image manipulation, and not generating images from scratch. SDL is’t intended to generate images from scratch either, but as far as i can tell its easier to manipulate images as int arrays.

Well it does work and i were able to try out some of the rules listed at Wikipedia article about Life like cellular automatons, there online java simulators somewhere on the Internets so I won’t bother to upload any videos – as its much more fun to watch in action an play about with the settings as you go along. If you want to play with the code, well here it is : Cellular Automaton code it’s ugly and you need CImg.h

And now I’ve just downloaded EvoCell which has all the features and a lot more.

Online simulator : MJcell this is a very good implementation. Its fast and has lots of rules and patterns

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