tile.js

define(function() {

    var Tile = Class.extend({
    });

    var AnimatedTile = Tile.extend({
        init: function(id, length, speed, index) {
            this.startId = id;
            this.id = id;
            this.length = length;
            this.speed = speed;
            this.index = index;
            this.lastTime = 0;
        },

        tick: function() {
            if((this.id - this.startId) < this.length - 1) {
                this.id += 1;
            } else {
                this.id = this.startId;
            }
        },

        animate: function(time) {
            if((time - this.lastTime) > this.speed) {
                this.tick();
                this.lastTime = time;
                return true;
            } else {
                return false;
            }
        }
    });

    return AnimatedTile;
});