Qu. Re: creating levels once the gameScene template is finished & passing data

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Qu. Re: creating levels once the gameScene template is finished & passing data

(11 posts) (4 voices)

Started 2 years ago by jonathan0382
Latest reply from Nicke

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jonathan0382
Member

Hi all, I have a question concerning the creation of levels, and the passing of level-specific data to the level.

I have been working for the last few weeks on a gameScene, and now that I have it (almost) perfected, I want to replicate it to make it into levels. The style of the game is that mostly everything in the game is the same save for a few variables that change # of sprites etc.

My first question concerns the creation of instances of the gameScene. I am currently doing this in my menuScene, when a level button is pressed, by calling this function:

-(void)level2: (id)sender {
GameScene *gs2 = [[GameScene alloc] init];
[[Director sharedDirector] replaceScene:[FlipYTransition transitionWithDuration:1 scene:gs2]];
}

This works great, so all I really need to know is it this is a good strategy or is it possible to create the scenes in an array and if so should I do this beforehand? The plan is for 20+ levels.

My second question concerns getting level-specific variables into (accessible by) the gameScene and it's layers. When I was creating the gameScene I just defined the variables I needed in the .h using define, such as: #define kNumberOfSprites 2
This was great for making the gameScene, and perfecting the game mechanic, but now I need to be able to change that definition depending on the level selected. I also need it to continue to be accessible by the layers within the scene. This is where I need help.

I am trying to create properties within gameScene and synthesize etc, and then in the menuScene pass the info like this:

-(void)level2: (id)sender {
GameScene *gs2 = [[GameScene alloc] init];
gs2.numSprites = 4; //<-- sets the number of sprites specific to this level. Property is int numSprites
[[Director sharedDirector] replaceScene:[FlipYTransition transitionWithDuration:1 scene:gs2]];
}

I have used properties of subclassed sprites before without problems, so didn't think this would be difficult, but I'm struggling and I feel like I'm on the wrong track. Is there a better (working!) way of changing If anyone could lend a hand I'd appreciate it.

Thank you, jonathan

Posted 2 years ago #
ob1
Member

Personally I made a class called "LevelConfig" with all the configuration items needed as property. Level has a class method getLevelConfigForLevelNumber.

In another project, I made a configuration dictionary for each level.

Then you probably need to add a new initialiser to your "GameScene", something like initWithLevelNumber;

Posted 2 years ago #
jonathan0382
Member

Thanks for the help. I haven't had time to look into it yet, but if you have the initWithLevelNumber within the GameScene, how would the value of the level number be passed into the GameScene in the first place so that it could request the correct level data?

Thanks

Posted 2 years ago #
ob1
Member
I am not sure I understand your question.

The whole point of initWithLevelNumber is to pass the level number to the GameScene on init.

Something like:
```
- (id) initWithLevelNumber:(NSUInteger) levelNumber
{
   if (self = [super init])
   {

   self.level = [Level getLevelforLevelNumber:levelNumber];

   self.numSprites = self.level.numsprites;
   ...
   }

return self;
}
```
getLevelForLevelNumber can basically have a "switch" clause in it's init and fill the various properties accordingly.
Posted 2 years ago #
jonathan0382
Member

I had a go at this today and it was successful, so thank you :)

One further question, purely because I'm thick!

How do I access a scene's variables (those defined in the init) from within the layers that are children of the scene?
For example, in GameScene I have a variable called "cookies" (?!), and I need to access it in GameLayer, which is a child of GameScene. In my ignorance I figured I could make it a property and synthesize etc, and access it using GameScene.level, but then I get an error accessing unknown level class method. I've used properties before so I'm not sure why...

Posted 2 years ago #
Korki696
Member

I know you only need to access it on the scene but one way, it may be a bit extreme for what your doing, it is used in the gorillas app and that is to make pretty much a gameConfig file and define all of your game variables there, such as score, level, lives. and that way you can access it anywhere in your project as long as you include that game config file. take a look at that source code.
-Lars

Posted 2 years ago #
jonathan0382
Member

Thanks for the pointers. I am able to access variables from a config file, such as in this link:
http://discussions.apple.com/thread.jspa?threadID=1592519

However, what is annoying me at the moment is that I define a variable in my GameScene, add a layer, and then cannot access that same variable from within my layer. It's annoying because I don't think this should be difficult! Even setting it up as a property doesn't help.

So the question still stands, and any help with it would be greatly appreciated:

How do you access a scene's variable from within a child layer?

e.g.
@interface GameScene : Scene {
NSInteger test;
}
@end
---------
@implementation GameScene
-(id)init
{
self = [super init];
if (self != nil) {
test = 3;

///other code, add gameLayer as child
}
return self;
}
@end

@implementation GameLayer
- (id) init {
self = [super init];
if (self != nil) {
Sprite *pause = [Sprite spriteWithFile:@"Pause.png"];
[pause setPosition:ccp(29, 29+test)];
//comes back as test is undeclared in this function GNYAH!

Posted 2 years ago #
Korki696
Member

Take a look at this i think that's what your trying to do.
http://tinyurl.com/kod53x
-Lars

Posted 2 years ago #
jonathan0382
Member

That's a good read. Thank you!

Posted 2 years ago #
jonathan0382
Member

Ok, I finally figured out how to do it. InitWith can be very useful! If anyone is interested let me know.

Posted 2 years ago #
Nicke
Member

If GameLayer is a child of GameScene....

parent.cookies = @"Moar cookies!";

Posted 2 years ago #

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