Learning iPhone Game Development with Cocos2D 3.0

Time for action – adding more birds

We are going to add more Bird objects to fly around. To do this, we're going to replace our _bird variable with an array and write some code to spawn the birds:

1. Open the GameScene.m file and remove the _bird variable. Instead, add two new instance variables to the GameScene class, as shown in the following code:

   @implementation GameScene
   {
       CCSpriteBatchNode *_batchNode;
       
       Hunter  *_hunter;
   
       float _timeUntilNextBird;
       NSMutableArray *_birds;
   }

2. Add following method somewhere below the update: method:

   -(void)spawnBird { //1 CGSize viewSize = [CCDirector sharedDirector].viewSize; //2 int maxY = viewSize.height * 0.9f; int minY = viewSize.height * 0.6f; int birdY = minY + arc4random_uniform(maxY - minY); int birdX = viewSize.width ...