Time for action – making the bird move

It is nice to have a cute bird on the screen, but our hunter can't shoot an unmoving bird, as this is simply not sportsman-like. So, before we give our hunter the ability to shoot, we're going to make the bird fly.

1. Open the GameScene.m file and add the following update: method below all other methods:

   -(void)update:(CCTime)dt
   {
       //1
       CGSize viewSize = [CCDirector sharedDirector].viewSize;
       
       //2
       if (_bird.position.x < 0)
           _bird.flipX = YES;
       
       //3
       if (_bird.position.x > viewSize.width)
           _bird.flipX = NO;
       
       //4
       float birdSpeed = 50;
       float distanceToMove = birdSpeed * dt;
       
       //5
       float direction = _bird.flipX ? 1 : -1;
       
       //6
       float newX = _bird.position.x + direction * distanceToMove;
       float newY = _bird.position.y;
       
       //7
       _bird.position = ccp(newX, newY);
   }

2. Now build and run the game. You should see the bird moving from the left edge of the screen to the right edge...