Tresvita Documentation

Tresvita v3.1 A Three Dimensional Cellular Automata Programmed by Alexander Mieczyslaw Kasprzyk, © 1997 1 Introduction A cellular automata is a lattice of cells which are used as both memory and processing elements. This lattice of cells can exist in any dimension and can be of infinite size. At any given time each cell can be in one of any of a finite number of states. The transitions between states from one time step to the next (from one iteration to the next) depends upon the state of the cell and the neighbouring cells states. Each state is defined by clear rules, and these rules apply to all the cells on the lattice and at all times. The configuration of cells in the next time step is determined entirely by the current arrangement of cells – past arrangements have no direct influence over future cell arrangements. Perhaps the most famous cellular automata was developed by John Conway. In Conway’s “Life”, which is played in an infinite two–dimensional board where each cell is a square (and therefore has eight neighbouring squares). There exist only two possible cell states – on (or “alive”) and off (or “dead”). The rules are very simple: if a cell is off it remains off in the next time step unless there are exactly three neighbouring cells in the on state, if a cell is on it remains on unless there are more than three “on” neighbours or if there are less than two “on” neighbours. The patterns produced from these simple rules are amazing, with many “life–like” structures emerging (such as “gliders” which “walk” diagonally across the board). Tresvita is very similar in idea to Conway’s “Life”. In Tresvita there exist only two possible cell states, “alive” and “dead”, and the rule sets are defined in a very similar way. The major difference is that Tresvita is a three dimensional cellular automata. 2 Loading Tresvita Tresvita is a FAT application. This means that it runs on both traditional 68K Macintosh computers and also on the newer Power Macintosh (PPC) computers. When running on a PPC machine it takes advantage of the more powerful features available and so should run considerably faster than on standard 68K Macs. Tresvita requires a minimum of System 7.0 to run. If you are running Tresvita using a version of the system software older than System 7.5 you will need to install the Thread Manager extension available free from many sources. The minimum amount of free memory needed to safely run Tresvita is 1Mb, but I suggest 4Mb if you want to run several large “growths” at once. 3 The Program 3.a Starting a New Growth First load Tresvita (if you have not already done so) by double–clicking on the application’s icon. To start a new growth select New from the File menu (or press command–N). A dialog box will appear. When you are satisfied with the settings in the dialog box click on the OK button (or press return) to start t…