Cocos2d animations in main loop

Question

Anyone that can give any hint of the smartest way to do a main loop animation? I don't want to use CCAnimation because I want to control the animations frame by frame.

Shall I store the sprite rect (relative to the sprite sheet) for each individual frame in an array, and then look up the suiting rect in each animation step? I tried to find out how this is done in CCAnimation, but I didn't succeed...

1. How to get the rect for each frame at initialization?
2. How to set the rect at each animation step?
3. Do I need to use CCSpriteBatchNode? I guess not, eh?

Answer 1

Cannot crealry understand, why you don't want to use CCAnimation, but anyway, to get answer for your questions you can check creation code of the CCSprite instance. Then, check creation of CCSpriteFrame instance. There you will find the answer for at least your first question.

Actually if you just want to manage animation frames differently from CCAnimate, you can just store array of CCSpriteFrames and show them as you want(in CCAnimate action these frames are just changed one by one in equal time intervals).

And if you do not want to show more than one frame of your animation, there is no difference will you use CCSpriteBatchNode or not. It saves a lot of processor time if you need to draw several parts of one texture, as it draws them in one draw call instead of send draw message to all of these sprites.

Answer 2

As you want animate sprite frame by frame I think using CCSpriteBatchNode would be a better option as it give you frame by frame access of animation.Making plist of sprites using any tool like "Zwoptex" will give an efficient way to animate using CCSpriteBatchNode.

Hope you know the animation using plist file with CCSpriteBatchNode.

Answer 3

I did the following with inspiration from Morions answer: In the game tick function:

_animationFrames.legFrame = (_animationFrames.legFrame + 1) % _animationFrames.legFrames.count;

[_legs setDisplayFrame:  [_animationFrames.legFrames objectAtIndex: _animationFrames.legFrame]];

And in the init function:

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

_animationFrames.legFrames = [[NSMutableArray array] retain];
for(int i = 0; i <= 15; ++i)
{
  [_animationFrames.legFrames addObject:
   [[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:
    [NSString stringWithFormat:@"Player_legs-%d.png", i]]];
}

_legs = [CCSprite spriteWithSpriteFrameName:@"Player_legs-0.png"];
[_sprite addChild: spriteSheet];
[spriteSheet addChild:_legs z:1];