Problem with z-order and overlaps

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Problem with z-order and overlaps

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Started 2 years ago by Dan
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Dan
Member

So in the current game I am writing, I have characters which open up chat bubbles with text written in those bubbles.

The sprite characters (AtlasSprites) are on one sprite manager, the chat bubble images (also AtlasSprites) are on another, and the labels (BitmapFontAtlas)I have placed in their own layer for easy removing (as BFA doesnt support multi-line and I'm loading from a bitmap font, giving a 3-line chat line 3 tags when there may be 5 chat bubbles on the screen, getting rid of them is a problem).

Anyway, the problem is this: The chat bubble in front of the character, and the BFA in front of the bubble. All good. Now, I have another character who, to leave the screen, must pass in front of another character. In doing so, he may/may not pass in front the other character, but since the Z-order for the sprite manager for the chat bubble & the label must be higher Z than the characters to show them in front, it puts me in a dilemma that I dont know how to move that character who needs to leave to be in front of the chat bubble. He cant leave behind the character since he's basically up against a wall (visually).

Since they are on different managers, I dont know what to do.

Any suggestions?

Posted 2 years ago #
Dan
Member

I guess this post sorta gives me a possible workaround:

http://www.cocos2d-iphone.org/forum/topic/1221

Will give it a shot and see if there's any performance hits.

Posted 2 years ago #
Dan
Member

Well, I tried to implement the swap managers method, but it seems to work fine the first swap (from original to new), but on calling the swap again, there is an assert thrown on the TextureAtlas removeQuadAtIndex when the removeChild is called. I can see that on the first swap, the totalQuads on the 2nd AtlasManager getes incremented, but on the remove when I swap back i am seeing that it is 0, thus throwing the assert.

I thought that it may have something to do with the 2 atlasmanagers pointing to the same image file, but I even tried to create the 2nd atlas manager with a copy of the sprite image.

Not sure where to look anymore.

Posted 2 years ago #
Steve Oldmeadow
Administrator

Do you really need to use AtlasSprites for this? I would guess performance with normal Sprites would be fine.

Posted 2 years ago #
Dan
Member

I'm not sure if I do need AtlasSprites. I'm still unclear on the interface differences between Sprites and AtlasSprites. Currently I have 8 AtlasSprites grabbing off the same sprite sheet (each with about 8 frames of animation).

Are you suggesting using Sprites and putting those directly onto the Layer/Scene and then putzing with the Z-order?

Posted 2 years ago #
Steve Oldmeadow
Administrator

AtlasSprites are great if you are drawing lots of sprites but what you are describing doesn't sound like that is the case. Even if the frame rate was lowish (which I doubt it will be) what kind of frame rate do you need really need for a dialog screen? If you use Sprites you won't have the z ordering problems. You can even group the character, their speech bubble and text into a layer or do something like make the speech bubble a child of the character sprite.

Posted 2 years ago #
Dan
Member

Well, its not just a dialog screen, I have about 30 other sprites going on at the same time in the scene. But I'll give it a shot converting from AtlasSprite to regular Sprites. I still dont understand why the switch to another AtlasManager would seemingly work once, but wont switch back.

Posted 2 years ago #
Dan
Member
Hmm, changing from an AtlasSprite to a Sprite is going to be ridiculously time-consuming as I'd have to redo all the animation code, and split the art into individual files for each of the 8 characters. Will exhaust the AtlasSpriteManager switch before I tackle that.

Here's the test code I'm calling:

On an init in my CustomerManager class:
```
m_customerSpriteManager = [AtlasSpriteManager spriteManagerWithFile:@"b-customers2.png" capacity:50];
		swapSpriteManager = [AtlasSpriteManager spriteManagerWithFile:@"b-customers3.png" capacity:50];
```
Same background art, just different filename to test whether or not it was trying to remove the same texture.
```
-(void) migrateSprite:(AtlasSprite*)sprite from:(AtlasSpriteManager*)from to:(AtlasSpriteManager*)to
{
	NSLog(@"MigrateSprite: IN");
	[sprite retain];
	NSLog(@"Parent: %d", [self parent]);
	[from removeChild:sprite cleanup:YES];
	NSLog(@"MigrateSprite: REMOVED");

	[to addChild:sprite	z:10 tag:spriteType];
	NSLog(@"Parent: %d", [self parent]);
	NSLog(@"MigrateSprite: ADDED");
	[sprite release];
	NSLog(@"MigrateSprite: OUT");
}
```
As a test to swap, I call this from my Customer class:
```
[self migrateSprite:self from:myManager.m_customerSpriteManager to:myManager.swapSpriteManager];
	[self migrateSprite:self from:myManager.swapSpriteManager to:myManager.m_customerSpriteManager];
```
The first swap goes through, although the z-order of the swap manager does not seem to be 'used', as I still see the sprite move in its lower z if I were to call the swap once. In any case, the second swap dies on the removeChild call, with an Assertion failure in -[TextureAtlas removeQuadAtIndex:] with an invalid index.

What am I doing wrong?

Thanks for all the assistance, I appreciate it.

-Dan
Posted 2 years ago #
Dan
Member

FYI, I gave up on this when I saw that I could not place any text labels (Label, AtlasLabel, BitmapFontAtlas) onto an existing AtlasManager, thereby unable to control z-order of individual items within the manager and outside.

Perhaps Riq can re-engineer one of the label classes so that it can live in an AtlasManager one day. Due to time constraints I cant roll my own class now, but will look into if I have the chance, or if there is no other workaround.

Posted 2 years ago #

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