CCSpriteBatchNode, composition and running actions

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CCSpriteBatchNode, composition and running actions

(17 posts) (4 voices)

Started 1 year ago by codedToDeath
Latest reply from shadiradio

Tags:

codedToDeath
Member

Hey, I've used a CCNode as the base for my game objects. Then I have CCSprite(s) as member objects, so that they can be assigned various graphic elements, but the subclassed CCNode acts as a container for everything.

My problem arises from integrating CCSpriteBatchNode. Since the CCSprites are added as children of the batch node and not the CCNode (the only attachment is the batch node is added to CCNode using useBatchNode), I'm having trouble animating the CCNode, i.e. with actions. I override the position methods in the CCNode to apply position changes to my CCSprite(s). When I try to use runAction on the CCNode (e.g. trying to move it from position A to position B) but nothing happens. The CCSprites don't move anywhere. I didn't have this issue before when the sprites were children of the node. But now since they are children of the batchnode, animating the node and sprites as a unit is not working.

Does anyone have a suggestion on how to solve this issue or a better way to setup "game objects"?

Note: I tried overriding the runAction method in CCNode and applying the action to the CCSprites. This did animate the sprites however, an error was generated because the callback function failed since it was calling a method in the layer not in the ccnode.

Posted 1 year ago #
araker
Moderator

I guess you can't add the batchnode as a child to the node, since you'll need it for other nodes as well. Another way is to make one of the sprites the parent of the other sprites, that way the parent sprite can act the same way as the node does now. There are not a lot of options if you want to use a batchnode and structure your sprites, since the batchnode only accepts sprites as descendants.

Posted 1 year ago #
codedToDeath
Member
I've made the CCNode into a CCSprite. Currently, since I only have one member CCSprite, I've removed this member and made the game object itself (it's a CCSprite now). In my init method I set the texture of self using setDisplayFrame. self is a child of the batchnode. This only seems to work for me if I do not call [self useBatchNode:_batchNode]. I'm not sure if useBatchNode is necessary, but when I include it, it throws an assertion (line 988 from CCSprite):

NSAssert( ! usesBatchNode_, @"CCSprite: setTexture doesn't work when the sprite is rendered using a CCSpriteBatchNode");

To give you an idea of how things are setup, I'm reusing the example init from our other conversation...
```
-(id) initWithBatchNode:(CCBatchNode*) batchNode {

	if ((self=[super init])) {

		_health = 100;

                //weak ref (= no retain)
                _batchNode=batchNode;

               [self useBatchNode:_batchNode]; // ** ASSERTION ERROR! But if commented out, everything works fine. **

               [self setDisplayFrame:[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName: [NSString stringWithFormat:@"player-body.png"]]];

		[_batchNode addChild:self];

         }
        return self;
}
```
In the thread http://www.cocos2d-iphone.org/forum/topic/11729, the user TBBle suggested that the important part was that the sprite was a child of the batchnode.

It feels like something is not right if I have to remove useBatchNode to get it to work.
Posted 1 year ago #
araker
Moderator

UseBatchNode is necessary, else the sprite will render itself instead and you'll have no performance gain.

You can't use setDisplayFrame in combination with a batchNode, use setTextureRect instead. It isn't necessary to save a reference to the batchNode, since your class is a subclassed sprite useBatchNode will fill the batchNode_ property.

Posted 1 year ago #
codedToDeath
Member
Hey @araker I appreciate the help, this batchnode stuff has been pulling my hair out all morning.

As you can probably decipher, I'm using a CCSpriteFrameCache where I add my frames from a plist file -- generated from a sprite packing tool. Currently I'm referencing the frame this way (taken from above):
```
[self setDisplayFrame:[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName: [NSString stringWithFormat:@"player-body.png"]]];
```
You're saying use setTextureRect instead, but when I try to grab the rect from a CCSpriteFrame, the addChild to batchnode gives an assertion error saying "CCSprite is not using the same texture id". Here is what I tried:
```
CCSpriteFrame *sf = [[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:[NSString stringWithFormat:@"rplayer-body.png"]];
[self setTextureRect:sf.rect];
```
I want to use the coordinates setup in the sprite sheet that I created from the sprite packing tool. What should I be doing?
Posted 1 year ago #
araker
Moderator
Two things you can do here, set the texture to the texture of the batchnode, ie

texture_=batchNode.textureAtlas.texture;

It's recommended though to use a different initializer when subclassing a sprite, probably to avoid situations like this. I use the following in my own code (not with a spriteframe, but with a predefined CGRect).
```
-(id) initWithBatchNode:(CCBatchNode*) batchNode {

      if ((self=[super initWithBatchNode:batchNode rect: [[[CCSpriteFrameCache sharedSpriteFrameCache] spriteFrameByName:[NSString stringWithFormat:@"rplayer-body.png"]] rect]))
      {
		_health = 100;
 		[_batchNode addChild:self];

         }
        return self;
}
```
Posted 1 year ago #
shadiradio
Member

I believe I'm running into a similar issue. I want to use a single CCSpriteBatchNode in my scene to have 1 GL call. I have subclassed CCNode to create other objects in the world (lets call them Widgets), and these Widgets have multiple CCSprites as properties. In order to benefit from the batch node, I have to add these sprites as children of the batch node rather than children of the Widget, but then they don't benefit from all the relative translation/transformation properties of the Widget (similar to codedToDeath's initial post in this thread).

It seems like you went with subclassing CCSprite, but what if I have multiple sprites in this object? There must be a good solution.

In a nutshell, I want the CCSprite properties of a Widget class to be the children of a batch node that resides in a scene for performance gains, but I want the sprites to receive the inherited translational properties of the Widget class. Without being the child of two parents, how is this possible? Or does it need to get ugly...

Thanks!

Posted 1 year ago #
araker
Moderator

You could define parent child relations between the sprites, instead of adding them all to the batch node directly. Best would be if one sprite is the parent for all the sprites in the widget and only that sprite is added as a child to the batchnode.

To make the sprites honor the transformations on the node, override the position, rotation, scale methods of your widget and change the properties of that parent sprite as well. It's a bit more expensive since every transformation has to be done twice, but it's the only way to accomplish that.

Making your widget a CCSprite would be the most efficient solution. Presuming you don't have hundreds of these widgets, you could give them a empty texture rectangle to avoid it from drawing something visible on screen, without much performance impact.

Posted 1 year ago #
shadiradio
Member

Thanks araker... after poking around a bit, I think I am indeed going to try making the objects subclasses of CCSprite themselves. If I understand the API correctly, it says all grandchildren of the batch node will also be rendered in that same GL call. My plan is to structure it like this:

Scene
-----Layer
----------Batch Node
---------------Widget (subclass of CCSprite, with an empty texture)
--------------------CCSsprite property (child of Widget, NOT batch node)
--------------------CCSsprite property (child of Widget, NOT batch node)
---------------Another Widget
--------------------CCSsprite property (child of Widget, NOT batch node)
--------------------CCSsprite property (child of Widget, NOT batch node)

Those CCSprites within the Widgets should get rendered in the batch GL call, right? Thanks again!

Posted 1 year ago #
araker
Moderator

Yes, all widgets (and all children) will be drawn in one batch.

Posted 1 year ago #
shadiradio
Member

I believe I have this structurally and visually working as described in my last post, but I can't run any actions on the CCSprite children of the widget (the actions don't do anything)... similar to codedToDeath's first post. :(

I also had to add a custom drawing node with a high z order that queries all my Widgets from the layer to perform any custom drawing they need, since the draw function is not called because the batch overrides it (and I need to do some openGL drawing for some objects).

This is sort of turning out to be a little insane... I'm wondering if getting all of these into one GL call is worth it. I'm really shooting for this to run great on all devices.

P.S. - Thanks for all your help so far!

EDIT: I have actions working, basically by running the 'onEnter' method manually when instantiating my custom class (since it never formally enters the stage I guess). Now onto figuring out some nested z-order problems... :D
EDIT 2: I jumped the gun. Actions are still sort of messed up. This is kind of a mess.

Posted 1 year ago #
shadiradio
Member

Ok after much fiddling, no matter how I structure it, I keep running into various different issues, especially with positioning and actions. All of this feels a little bit like spaghetti code, and it kind of messes with logical object-oriented design in my head. :(

I really wish there was a way to have CCSprites be normal children of any node, but somehow defer their drawing to a batch node so that logically organizing them and positioning them, etc made sense from a design perspective.

Posted 1 year ago #
Benihana
Member

I want to use a single CCSpriteBatchNode in my scene to have 1 GL call.

Why is this such a priority? Are you sure you need the performance benefits? It seems you're optimizing a bit early at the price of proper organization.

Posted 1 year ago #
araker
Moderator

Try to add

isRunning_=YES;

to the init method of the subclassed sprite. For me the actions work like a charm, without any positioning issues.

Posted 1 year ago #
shadiradio
Member

Thanks araker, I'll give it a shot.

Benihana: I hear you, I'm just a fan of optimizing early when I know I'll most likely be doing it later - it helps me structure my code from the outset. I did a ton of refactoring on my last game when I added high resolution graphics and I'm trying to use some of what I've learned from the get go.

For this current game, I have 80 nodes that are essential to the core of the gameplay, and each has 2 sprites within it. Then there are a few dozen other sprites providing scenery, interface, etc. I think getting the batch node working correctly here is essential. :/

Posted 1 year ago #
Benihana
Member

For this current game, I have 80 nodes that are essential to the core of the gameplay, and each has 2 sprites within it. Then there are a few dozen other sprites providing scenery, interface, etc. I think getting the batch node working correctly here is essential. :/

Hmm, perhaps I'm not explaining this properly.

It seems that your organization is being severely limited by your desire to use spritesheets.

My best suggestion would be to create an NSObject hierarchy of custom objects which are directly tied to the nodes, and emulate the behavior of nodes which you expect to adjust (scale, position, rotation, etc). Then, don't manipulate your sprites at all, just manipulate this parallel hierarchy and have it pass position and all that to the sprites they are tied to.

Kind of a "virtual node" setup.

Posted 1 year ago #
shadiradio
Member

Man, I finally have everything working with one batch node drawing everything. I'm not sure if it was worth it since I'm doing this from the start, but with that out of the way I don't have to worry about it at all, I can add my sprites to it at will. I fixed everything by subclassing CCSprite for my objects. My positioning/action problems before were do to the timing of adding objects to the scene. Araker's note about is_running got me on the right track about why they weren't responding.

Benihana - I think that would work as well, and it actually sounds a lot like using a physics engine and updating related nodes' sprites to match physics bodies. In fact I'm using chipmunk for part of this, that reminded me a lot of it.

Anyway, that's a load off.

Posted 1 year ago #

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