text: (function(root){
    if(typeof Asteroids === "undefined") {
      root.Asteroids = {};
    }
  
    var Util = Asteroids.Util = {};
  
    Util.inherits = function(ChildClass, ParentClass){
      var Surrogate = function() {};
      Surrogate.prototype = ParentClass.prototype;
      ChildClass.prototype = new Surrogate();
      ChildClass.prototype.constructor = ChildClass;
    };
  
  Util.randomVec = function(length) {
      return [0, length];
    };
  
    Util.norm = function(vel) {
      return Math.sqrt(
        Math.pow(vel[0],2) +
        Math.pow(vel[1],2)
      );
    };
  
    Util.normalize = function(vel,length) {
      var norm = length/Util.norm(vel);
      return [vel[0]*norm, vel[1]*norm];
    };
  
  })(this);
  