Question

It’s hard to get the exact specific information on OOP you’re searching for.
I tried to keep it as short as possible:

I’m currently developing a jump n run in HTML5.
I have actually no real experience with developing games.
But I know how the basics are supposed to work.
I just want to know if I’m doing it right.

I have a game, player and level object.

What I’m currently doing is the following:

Game.player = new Player();
Game.level = new Level();

Game.level.load(Game.currentLevel);
...
Game.run();

Is that the best way or should I call them all on their own, e.g.:

var Player = new Player();
var Level = new Level();
Level.load(Game.currentLevel);
...
Game.run();

They way I’m doing it right now (the first one) seems more logic to me.
But.. in the level objects functions I have to check for various variables from the game object or call a function of its self. Thus I have to write Game.level.funcName inside the Level objects functions. But since Game.level doesnt actually exist at the level objects declaration point it feels kinda wrong and dirty. Here is another example:

Level.prototype.reset = function() {
    this.load(Game.currentLevel);
};

The Game.currentLevel is hardcoded, isn’t there any better way to detect which variable currently handles the game object, or is it totally ok the way I’m doing it ?

So the basic question is, whats the best way to let objects interact with each other ?

And one last question which is kinda offtopic, but what does ()(); do?
I sometimes see it beeing used like this:

(function() {
    // Content
});

I hope you understand my concerns, thanks for your time and answers. 🙂

Answer 1

I would recommend the first approach, because it’s more modular.
Your problem can be solved by simply passing a reference of the Game instance to the other components, so that they are aware of the game.
It’s not uncommon for objects to have a cyclic structure in javascript:

Game.level = new Level();
Game.level._game = Game;
//...
Level.prototype.reset = function() {
    this.load(this._game.currentLevel);
};

Of course that you can do it a bit more elegant by passing reference at initialization, but I think you got my point.