DOB

Hi to all!

Today I’m going to explain one little tip I found few days ago. This is not a real howto or a big manual, but only a little trick to make your games even better.

The problem

In my game I have one menu in which one of the options is “start game” and, when you touch this option the scene of cocos changes to the game scene.
In the game scene there is some object that have a box2d body and some velocity and this objects are set in the very begining of the scene (I mean, in the init method).
What I wanted to do is to stop the game just in the moment the game scene starts and wait until the “touch” event of the user to resume game, but I didn’t wanted to change my init method or anything.

The solution
The easy solution that I thought was to put an [[CCDirector sharedDirector] pause]; in the end of the init method…but… this is not good for what I wanted because I was pausing the game before the scene object is returned. And the effect was that I was pausing the game in the menu scene, not in the game.
So, the final solution that was great for me was pretty simple too.
- first of all I had to set my “replace scene” method for one call with transition. Just like this:

 [[CCDirector sharedDirector] replaceScene:[CCCrossFadeTransition transitionWithDuration:0.5f scene:[Attack scene]]];

- second and was to set the onEnterTransitionDidFinish method in my game scene:

 -(void) onEnterTransitionDidFinish{
	[super onEnterTransitionDidFinish];
	[[CCDirector sharedDirector] pause];
}

It’s very important the “super” call inside the method.

- And the last thing was to set the resume call in the correct position. In my case was in the touchesBegan method:

-(void)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
// boring code	
	[[CCDirector sharedDirector] resume];
//more boring code
}

And that’s all.

So, as always, hope you liked it and enjoy

First of all: Hi, and welcome to my new blog

For my first post I am going to talk about a little thing that I am using in my new game that I hope will be on app store in a few days.

This thing I call auto-hidden labels..this is because are labels and are self-hidden Ok, stop joking and start with the code.

The game I am developing is some kind of breakout game and as this we have a ball, a pallete and some blocks to destroy. When the ball touches a block it destroys.

My problem was that I wanted to show a little text telling how many points the user won destroying this block. For that I tried some different things, but I didn’t liked any of them a lot. So..I developed my own solution.

This is what I wanted

For that I started creating one CCLabel’s son object and I called it “LabelToDie”. I know, so smart name And this is the code for

LabelToDie.h:

@interface LabelToDie : CCLabel {
	float dt;
}
 
@property (nonatomic) float dt;
 
-(id) initWithText:(NSString *)text size:(float)size time:(float)dt;
 
@end

LabelToDie.mm

#import "LabelToDie.h"
 
@implementation LabelToDie
 
@synthesize dt;
 
-(id) initWithText:(NSString *)text size:(float)size time:(float) dt1{
	if ((self=[super initWithString:text fontName:@"Verdana-Bold"  fontSize:size])!=nil){
		self.dt = dt1;
	}
	return self;
}
@end

So, with this we’ve got a brand new label with a time of creation. Now, with this class we have to:

1.- Create the label with the time and position
2.- Destroy labels that have been created a long time ago

Go with it:

1.- In our collision detection method we have to destroy the bad block and show the new label in its position:

-(void)tick:(ccTime)dt{
//some collision detection code and get the sprite to destroy
//...
LabelToDie *labelPoints = [[LabelToDie alloc] initWithText: [NSString stringWithFormat:@"%d", pointsToPut] size:12.0 time:dt];
 
labelPoints.position = ccp(sprite.position.x, sprite.position.y);
labelPoints.color = ccc3(0, 150, 0);
 
[self removeChild:sprite cleanup:YES];
 
[arrayLabels addObject:labelPoints];
[self addChild:labelPoints];
// some other boring code

2.- So this is the real clue. We are maintaining an array of labels called arrayLabels (another smart name) and with it finally we only need to check this array in our tick method and see if has passed so many time

//same boring code of before
int numLabels = [arrayLabels count];
 
for (int l=numLabels-1; l>=0; l--){
	LabelToDie * ld = (LabelToDie *)[arrayLabels objectAtIndex:l];
	if (([ld dt])>0.4){  //Check that the time passed is more than 0.4
		[self removeChild:(CCLabel *)ld cleanup:YES];
		[ld release];
		[arrayLabels removeObjectAtIndex:l];
	}else {
		[ld setDt:[ld dt]+dt];
	}
}
} //close the tick method

And that’s all! As you saw is very easy and you can use this method for show lives up or lives down, points, etc..

Hope you liked and bye!

Edit:

You should read the two comments of Gaming Horror in this post for a very improved version of this LabelToDie code. Enjoy!!!