Question

i have three simple images each for 2 hens (6 images) which I am trying to animate (a hen walking) using a very good tutorial by Ray Wenderlich:

http://www.raywenderlich.com/1271/how-to-use-animations-and-sprite-sheets-in-cocos2d

The animation works fine when I start the game but after 2-3 mins the Frame Rate begins to drop and slowly it drops to below 10 and the application hangs.. btw I am using iPhone 3G with iOS 4.1 … can that be the reason for the FPS drop or just the iPhone becomes idle after some time?

[[CCSpriteFrameCache sharedSpriteFrameCache] addSpriteFramesWithFile:@"hen.plist"];        


CCSpriteBatchNode *spriteSheet = [CCSpriteBatchNode batchNodeWithFile:@"hen.png"];
[self addChild:spriteSheet];

// Load up the frames of our animation
NSMutableArray *walkAnimFrames = [NSMutableArray array];
for(int i = 1; i <= 3; ++i) {
    [walkAnimFrames addObject:[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:[NSString stringWithFormat:@"%d.png", i]]];
}
CCAnimation *walkAnim = [CCAnimation animationWithFrames:walkAnimFrames delay:0.1f];

self.bear = [CCSprite spriteWithSpriteFrameName:@"1.png"];        
_bear.position = ccp(20,400);
self.walkAction = [CCRepeatForever actionWithAction:[CCAnimate actionWithAnimation:walkAnim restoreOriginalFrame:NO]];
[_bear runAction:_walkAction];
[spriteSheet addChild:_bear];

[[CCSpriteFrameCache sharedSpriteFrameCache] addSpriteFramesWithFile:@"monkey.plist"];        


CCSpriteBatchNode *spriteSheetMonkey = [CCSpriteBatchNode batchNodeWithFile:@"monkey.png"];
[self addChild:spriteSheetMonkey];

NSMutableArray *walkAnimFramesMonkey = [NSMutableArray array];
for(int i = 1; i <= 3; ++i) {
    [walkAnimFramesMonkey addObject:[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:[NSString stringWithFormat:@"%d.png", i]]];
}
CCAnimation *walkAnimMonkey = [CCAnimation animationWithFrames:walkAnimFramesMonkey delay:0.1f];


self.monkey = [CCSprite spriteWithSpriteFrameName:@"1.png"];        
_monkey.position = ccp(40,80);
self.walkMonkey = [CCRepeatForever actionWithAction:[CCAnimate actionWithAnimation:walkAnimMonkey restoreOriginalFrame:NO]];
[_monkey runAction:_walkMonkey];
[spriteSheetMonkey addChild:_monkey];
float bearVelocity = 480.0/3.0;

CGPoint moveDifferenceHen = ccpSub(HenLoction, _bear.position);
float distanceToMoveHen = ccpLength(moveDifferenceHen);
float moveDurationHen = distanceToMoveHen / bearVelocity;

self.moveAction = [CCSequence actions:                          
                       [CCMoveTo actionWithDuration:moveDurationHen position:HenLoction],
                       [CCCallFunc actionWithTarget:self selector:@selector(bearMoveEnded)],
                       nil
                       ];


[_bear runAction:_moveAction]; 

Answer 1

Sounds like you might have a memory leak. My advice would be to run the Leaks and ObjectAlloc Instruments on the device. Also, you should post the relevant code if you want more detailed assistance.