conway.js

/*! Copyright (c) 2011 Piotr Rochala (http://rocha.la)
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 *
 * Version: 0.1.0
 * 
 */
var Conway = function(){

    var gridSize = null,			//size of the game area
		pointsToFlip = [],			//Collection of this.points to flip in the next iteraton
		timer;						//Game Loop timer
	
	this.interval = 100;			//update interval
	this.gridNode = null;			//reference to table node
	this.showNeighboursNum = false; //sets if neighbours numbers should be displayed
	this.points = [];				//all this.points

	//Main Cell Object
	var ConwayPoint = function(x, y) {
		this.x = x;
		this.y = y;
		this.active = false;

		this.neighbours = function() {
			var neighbours = [];

			//Checkingthe boundries and getting all 8 cells around current (X) cell:
			// ABC
			// DXE
			// FGH
			if (this.x >= 1) {
				neighbours.push(conway.points[x - 1][y]); //D
				if (this.y <= gridSize.height - 2) { neighbours.push(conway.points[x - 1][y + 1]); } //A
				if (this.y >= 1) { neighbours.push(conway.points[x - 1][y - 1]); } //F
			}
			if (this.x <= gridSize.width - 2) {
				neighbours.push(conway.points[x + 1][y]); //E
				if (this.x <= gridSize.width - 2 && this.y <= gridSize.height - 2) { neighbours.push(conway.points[x + 1][y + 1]); } //C
				if (this.x <= gridSize.width - 2 && this.y >= 1) { neighbours.push(conway.points[x + 1][y - 1]); } //H
			}
			if (this.y >= 1) {	neighbours.push(conway.points[x][y-1]); } //G
			if (this.y <= gridSize.height - 2) {	neighbours.push(conway.points[x][y+1]); } //B

			var count = 0;
			for (var i = 0; i < neighbours.length; i++) {
				if (neighbours[i] != undefined && neighbours[i].active)
				{
					count++;
				}
			}
			return count;
		}
	}

    //Starts Game Loop
    this.start = function() {
		
        clearInterval(timer);
		var t = this;
        timer = setInterval(function(){ t.flippoints(); }, this.interval);
    },

    //Stops Game Loop
    this.stop = function() {
        clearInterval(timer);
    },

    //Updates cells display in front-end
    this.updateDisplay = function() {
        for (var x = 0; x <= gridSize.width - 1; x++) {
            for (var y = 0; y <= gridSize.height - 1; y++) {
                var point = this.points[x][y];

                this.gridNode.rows[point.x].cells[point.y].style.background = (point.active) ? "#f00" : "#ccc";

                if (this.showNeighboursNum) {
                    this.gridNode.rows[point.x].cells[point.y].innerHTML = point.neighbours();
                }
            }
        }
    },

    //Activates single point
    this.enablePoint = function(x, y) {
        this.points[x][y].active = true;
    },

    //Activates many this.points
    this.enablepoints = function(points) {
        $.each(points, function(i, val) {
            conway.enablePoint([val[0]][val[1]]);
        });
    },

    //Initializes the game
    this.init = function(gridNode) {
        this.gridNode = gridNode;
        gridSize = {
            width: this.gridNode.rows.length,
            height: this.gridNode.rows[0].cells.length
        };
        //reset all this.points
        this.clear();
    },

    //Clears game area and resets all this.points
    this.clear = function() {
        this.points = [];
        pointsToFlip = [];

        for (var x = 0; x < gridSize.width; x++) {
            this.points[x] = new Array(gridSize.height);
            for (var y = 0; y < gridSize.height; y++) {
                this.points[x][y] = new ConwayPoint(x, y);
            }
        }

        this.updateDisplay();
    },

    //Changes the state of every point of the game
	this.flippoints = function() {

        //clear list of this.points to flip
        pointsToFlip = [];

        //loop through all this.points..
        for (var x = 0; x < gridSize.width; x++) {
            for (var y = 0; y < gridSize.height; y++) {
                
				var point = conway.points[x][y];
                var neighbours = point.neighbours();

                //..apply main game rules
                if (point.active && neighbours < 2) {
                    pointsToFlip.push({ point: conway.points[point.x][point.y], active: false });
                }
                if (point.active && neighbours > 3) {
                    pointsToFlip.push({ point: conway.points[point.x][point.y], active: false });
                }
                if (!point.active && neighbours == 3) {
                    pointsToFlip.push({ point: conway.points[point.x][point.y], active: true });
                }
                if (point.active && (neighbours == 2 || neighbours == 3)) {
                    pointsToFlip.push({ point: conway.points[point.x][point.y], active: true });
                }
            }
        }

        for (var i = 0; i <= pointsToFlip.length - 1; i++) {
            pointsToFlip[i].point.active = pointsToFlip[i].active;
        }
        this.updateDisplay();
    }
}