Node test pattern

gistfile1.js

sys = require('sys');

function Cell(x,y) {
  this.x = x;
  this.y = y;
  this.state = (((x - 10) * (x - 10) + (y - 10) * (y - 10)) % 5) == 0
}

Cell.prototype.run = function() {
  if (this.state == true)
    mark(this.x, this.y);
  else
    unmark(this.x, this.y);
  this.state = !this.state;
}

clearScreen = function() {
  sys.print("\x1B[2J");
};

goto = function(x,y) {
  sys.print("\x1B[" + y + ";" + x + "H");
}

mark = function(x,y) {
  goto(x,y);
  sys.print("X");
};

unmark = function(x,y) {
  goto(x,y);
  sys.print(" ");
}

runCells = function(cells) {
  for(var index = 0; index < cells.length; index++)
    cells[index].run();
}

start = function() {
  var cells = new Array();
  var index = 0;
  var limit = 50;
  for(var x = 0; x < limit; x++) {
    for(var y = 0; y < limit; y++) {
      cells[index++] = new Cell(x,y);
    }
  }
  return cells;
}

clearScreen();

var cells = start();

function runner() {
  setTimeout(function() {
    runCells(cells);
    runner();
  }, 50);
}

runner();