Jquery-based address bar shooting game code

Demo address: http://demo.jb51.net/js/2011/hunt/index.htm

Look down
See the letter "O" in the address bar! You use O to fire. Use the left and right arrows on the keyboard to move the letter O. When O moves to a, press the Space key to shoot! The game will be scheduled for 30 seconds, and Press ESC to start again.
Note: Use the IE browser that comes with the system to open this link.

You use O AShooting. Use Left arrowAnd Right arrowMove letter O. When O moves AWhen, press Space keyShooting!
Core code:
Copy codeThe Code is as follows:
(Function (){
Var Animal, Game;
Var _ bind = function (fn, me) {return function () {return fn. apply (me, arguments );};};
Game = (function (){
Function Game (){
This. eventReceived = _ bind (this. eventReceived, this );;
This. update = _ bind (this. update, this); this. level = 1;
This. levelSize = 60;
This. playerLocation = this. levelSize/2;
This. start ();
}
Game. prototype. start = function (){
Var num;
This. points = 0;
This. startTime = new Date;
This. timeLimit = 30;
This. animals = [];
For (num = 4; num> = 1; num --){
This. addAnimal ();
}
Return this. interval = setInterval (this. update, 1000/30 );
};
Game. prototype. gameOver = function (){
ClearInterval (this. interval );
Return location. hash = "in" + (this. elapsedTime () + "seconds, you shot" + this. points + "! (Press ESC to start again )";
};
Game. prototype. elapsedTime = function (){
Return Math. floor (new Date). getTime ()-this. startTime. getTime ()/1000 );
};
Game. prototype. addAnimal = function (){
Var animal;
Animal = new Animal (Math. floor (Math. random () * this. levelSize ));
Return this. animals. push (animal );
};
Game. prototype. removeAnimal = function (deadAnimal ){
Var animal;
Return this. animals = (function (){
Var _ I, _ len, _ ref, _ results;
_ Ref = this. animals;
_ Results = [];
For (_ I = 0, _ len = _ ref. length; _ I <_ len; _ I ++ ){
Animal = _ ref [_ I];
If (animal! = DeadAnimal ){
_ Results. push (animal );
}
}
Return _ results;
}). Call (this );
};
Game. prototype. isAnimalAt = function (position ){
Var animal, matches;
Matches = (function (){
Var _ I, _ len, _ ref, _ results;
_ Ref = this. animals;
_ Results = [];
For (_ I = 0, _ len = _ ref. length; _ I <_ len; _ I ++ ){
Animal = _ ref [_ I];
If (Math. floor (animal. position) = position ){
_ Results. push (animal );
}
}
Return _ results;
}). Call (this );
Return matches [0];
};
Game. prototype. update = function (){
Var animal, position, timeLeft, url, _ I, _ len, _ ref;
Url = [];
_ Ref = this. animals;
For (_ I = 0, _ len = _ ref. length; _ I <_ len; _ I ++ ){
Animal = _ ref [_ I];
Animal. update (this. levelSize );
}
While (url. length <this. levelSize ){
Position = url. length;
If (position = this. playerLocation ){
If (this. isAnimalAt (this. playerLocation )){
Url. push ("@");
} Else {
Url. push ("O ");
}
} Else if (this. isAnimalAt (position )){
Url. push ("");
} Else {
Url. push ("-");
}
}
TimeLeft = this. timeLimit-this. elapsedTime ();
If (timeLeft <= 0 ){
Return this. gameOver ();
} Else {
If (timeLeft <10 ){
TimeLeft = "0" + timeLeft;
}
Location. hash = ("" + timeLeft + "|") + url. join ("") + ("|" + timeLeft );
Return document. title = "Points" + this. points;
}
};
Game. prototype. eventReceived = function (event ){
Var animal;
Switch (event. which ){
Case 37:
This. playerLocation-= 1;
If (this. playerLocation <0 ){
Return this. playerLocation = this. levelSize-1;
}
Break;
Case 39:
This. playerLocation + = 1;
Return this. playerLocation % = this. levelSize;
Case 38:
Case 32:
Animal = this. isAnimalAt (this. playerLocation );
If (animal ){
This. points + = 1;
This. removeAnimal (animal );
Console. log (this. animals. length );
If (this. animals. length = 0 ){
Return this. gameOver ();
}
}
Break;
Case 27:
Return this. start ();
}
};
Return Game;
})();
Animal = (function (){
Function Animal (position ){
This. position = position;
This. velocityChange = Math. random () * 0.5;
This. velocityIndex = Math. random () * Math. PI;
This. dampener = 0.4;
}
Animal. prototype. update = function (levelSize ){
This. velocityIndex + = Math. random () * this. velocityChange;
This. position + = Math. sin (this. velocityIndex) * this. dampener;
This. position % = levelSize;
If (this. position <0 ){
Return this. position + = levelSize;
}
};
Return Animal;
})();
$ (Function (){
Var game;
Game = new Game ();
Return $ (document). keydown (game. eventReceived );
});
}). Call (this );