Classes...is there any point?

[Xoria7]

Classes just seem so complicated and confusing in terms of how they work, and their structure. So what's the point of even using classes? Why not just pack all your AS in the same fla file?

[Jereminion]

At 8/11/09 03:50 PM, Xoria7 wrote: Classes just seem so complicated and confusing in terms of how they work, and their structure. So what's the point of even using classes? Why not just pack all your AS in the same fla file?

i dont know either. i went from as2 to as3 and i have all my coding in 1 fla file too. it runs just as well. there is 1000 lines of code right now and i am barely started with the game, but i have a monitor in portrait rotation so i can read it easily.

[Afro-Ninja]

Classes offer organization and structure

What happens when your game is ten thousand lines of code long? do you want to have to sift through the same window for your code or would you rather open up a file that you know contains it?

A class is used to represent a logical object in the game. If you have a main character, make a class for it. All variables, methods, and general behavior relating to that character will be contained within. When you need to make adjustments to the character, open up MainCharacter.as, and it's all there for you.

When you code on the timeline you can have fragments of code laying around everywhere, even nested within layers upon layers of movieclips

[Yannickl88]

hehe, this made me giggle

classes are at the core of OOP (object oriented programing) AS3 is so much better then AS2 thanks to the OO support. So if you do not see the use of classes, I recommend looking at the help at OOP.

I can't even make a flash game WITHOUT the use of classes, hahaha

[johnfn]

There's a certain threshold of lines of code you need to cross where suddenly classes become more helpful than annoying. I would say it's about 2000-3000 lines. Personally, I find classes are incredibly helpful for organization, debugging and code reuse.

[zuperxtreme]

I agree that after a certain amount of lines/complexity classes become "useful". For a 200-300 line project I doubt I'd use them.

[Jereminion]

At 8/11/09 04:17 PM, Afro-Ninja wrote: Classes offer organization and structure

What happens when your game is ten thousand lines of code long? do you want to have to sift through the same window for your code or would you rather open up a file that you know contains it?

A class is used to represent a logical object in the game. If you have a main character, make a class for it. All variables, methods, and general behavior relating to that character will be contained within. When you need to make adjustments to the character, open up MainCharacter.as, and it's all there for you.

When you code on the timeline you can have fragments of code laying around everywhere, even nested within layers upon layers of movieclips

hello i have a question about this. you said that classes represent objects in the game. in as2, you could simply put all the code on an enemy object, duplicate it as many times as you want, and the code on the movieclip applied to all of the enemies.

i am not using classes, so i am just doing a for loop for the dynamic actions of the enemies (using the array's length and using an array to store the movie clip names). if i used classes for multiple enemies and their actions, would i have to use a for loop also? i want to know because the enemies will have a few thousand lines of code and having them in 1 or more for loops will slow my game down.

[Afro-Ninja]

At 8/11/09 05:03 PM, Jereminion wrote: hello i have a question about this. you said that classes represent objects in the game. in as2, you could simply put all the code on an enemy object, duplicate it as many times as you want, and the code on the movieclip applied to all of the enemies.

when you use a class you would write all the code for that enemy in a separate file, link it to a movieclip in the library, and then create instances of it as needed. And yes, store them in an array and loop through them if need be.

i am not using classes, so i am just doing a for loop for the dynamic actions of the enemies (using the array's length and using an array to store the movie clip names). if i used classes for multiple enemies and their actions, would i have to use a for loop also? i want to know because the enemies will have a few thousand lines of code and having them in 1 or more for loops will slow my game down.

It doesn't really matter how many lines of code are 'on' the movieclip, it just depends what you're actually doing with those movieclips each time you loop. If you loop through them and call a 'checkCollision' function each time then the speed of that function will determine how efficiently the loop executes. It doesn't matter if you have another 800 lines of code that aren't being used.

[Arby]

You have no idea how much you rely on classes already =D

You see, something like a movieclip is a class and it has all those fun functions like x,y, rotation, etc. If you didn't have the movieclip class, you'd have to write all those functions by hand! Not fun!

This is why we use classes ;P

[zuperxtreme]

For example, I was making a TD game to play around with classes and my main problem was communicating between them.

From my document class I check the current level and initiate the level class, create the grid using the grid class and from within that(the level class) all the enemies are made(initiating the enemy class for each enemy).
The enemies are placed and moved in accordance to an array from within the level class, using a function within the enemy class.
So the enemies are attached at a set time given in the level class, moved with a function from their own class using coordinates from the level class...
Towers are made when a button is clicked(made with the interface class). They check the coordinates of the enemies and call one of their functions to shoot at it.

...

Anyways, to do all this I have to have communication between them. Which was a problem for me. I came upon something called a Singleton. I'm not sure what it is, but it's a sort of global container. I import that class everywhere I need information shared and access them using a dot operator. "global.myVar1, global.myArray2, etc".

My questions are:

Is this the right approach to OOP? Am I over complicating things? What exactly is a singleton? How would you share info across classes?

[johnfn]

Is this the right approach to OOP?

There is no single 'right approach', but it's looking fine.

What exactly is a singleton?

A class that only ever has one copy of itself.

How would you share info across classes?

A few different ways:

- public static functions (or member variables)

- return values from functions called

- (the least OOP way) public variables

It's all about having a reference to the class somewhere in the other class. After you've got that down, the rest is easy.

[zuperxtreme]

That's a thing. What exactly do you mean keeping a reference to it?

Importing it to every class? Would that drive up the file size?

[knugen]

ActionScript 3.0 Design Patterns is a pretty awesome book on how to make good code structures. Here's a sample chapter from the book :)

[zuperxtreme]

Awesome, man. Here's a more extensive preview of it:

http://books.google.com/books?id=lgk0Q7p MmLYC&printsec=frontcover&source=gbs_nav links_s#v=onepage&q=&f=false

[Xoria7]

Wow. I got more posts than expected. Well I did learn alot from you people.

[GustTheASGuy]

At 8/11/09 05:03 PM, Jereminion wrote: hello i have a question about this. you said that classes represent objects in the game. in as2, you could simply put all the code on an enemy object, duplicate it as many times as you want, and the code on the movieclip applied to all of the enemies.

That's quite how classes work too. Except instead of an original object you have a class that describes how new instances of it are created.
Everything you do in AS2 is hacks that people who liked OOP came up with long ago before AS had proper classes.

i am not using classes, so i am just doing a for loop for the dynamic actions of the enemies (using the array's length and using an array to store the movie clip names). if i used classes for multiple enemies and their actions, would i have to use a for loop also? i want to know because the enemies will have a few thousand lines of code and having them in 1 or more for loops will slow my game down.

Yes, you'll still need a loop. What the class can do is logically organize the code to do with your enemy objects. You can make the enemies automatically register themselves to the array of enemy objects, and add functions like 'follow', 'shoot', 'die'.

You can make your code look like this:

function onEnterFrame ()
{
  player.moveControls (); // move player, shoot bullets

  Enemy.forall (function (e) // enemy AI
  {
    if (e.passive)
    {
      if (e.canSee (player)) e.shoot (player);
      else e.moveAround (); // passive wander
    }
  });

  Bullet.forall (function (b) // bullet behavior
  {
    Enemy.forall (function (e)
    {
      if (b.hitEnemy (e)) { b.hit (); e.die (); }
    });
  });
}

Schedule.addEvent (Schedule.after (1000), function () new Enemy ());
// spawn enemy every second

[milchreis]

If everything is made of objects, a plan to create an object seems to be the ultimate master plan.

Play god, use classes, create objects; that's the way it goes.