After upgraded to ios7, I found the Cocos2d application run slowly (or frame skipped) after checking the notification center.
Reproduce the problem:
Launch a cocos2d game, better with some fast moving sprites
Swipe down from the top of the screen to drop down the notifaction center, then swipe it up.
Now the game becomes like frame skipped. (slow). But after a while, or after some operation within the game, the frame speed recovers.
I tested on iphone5.
Anyone see the same problem? Any idea how it happens?
EDIT:
Since this problem only happens in rare case, I d like to close it.
Related
Problem: I have a CCSprite animation that uses 7 frames. It works fine when I run the action with a delay of .04f, however, I need to run this animation at .02f which causes it to completely stop about 2~3 frames into the sprite animation. Bumping it up to .03f gets about 4~5 frames in before the sprite freezes.
I can't post the code because there's way too much. Really I'm looking for a general idea of where to start looking. The CCSprite I'm calling the runaction on is being retained, so that doesn't seem to be the issue. Thoughts?
I am trying to develop an 2D game using cocos2d library. I am still learning the framework.
Please understand that I am new to game development but not new to programming using objective c.
Here is the issue I am facing when it comes to my game development effort - I feel that I am missing the theoretical understanding of how to develop an infinite scrolling game. Is it possible for any of you to provide me some guidance on that ?
Here is my understanding of achieving infinite scrolling using cocos2d framework:
Cocos2d has a singleton director class which handles the current scene and scene transitions
In the current scene, I feel like I have to create an platform object consisting of several images and add them as a child to the current layer. And constantly run a move action to the platform sprite. So as and when I detect a particular image is off screen I have to replace it with another image. That way I will be able to create an infinite scrolling.
I am sorry if point 2 is not coherent. I just attempted to put my understanding of how to infinite scrolling.
Can you please help me with this ?
Thanks
I dissected how to implement scrolling with cocos2d-iphone in this article. What you probably want is the "fake scrolling" approach where two background images are moved and switch position after one completely left the screen.
You want to do this for the background layer only, not individual sprites. Your world isn't really moving, it's just the background panning that creates the illusion of movement. All sprites etc (player, enemies) movement is still relative to screen coordinates.
You'll find a working implementation in the code for my Learn Cocos2D 2 book in the Shoot'em Up project.
If you don't want to bother implementing this yourself, KoboldTouch supports endless/infinite scrolling for tilemaps. Here the game objects actually move along with the background infinitely (up to the maximum coordinates supported by float which is around +/- 16 million points).
I am trying to create a simple game that mainly consists of a ball rolling down an incline. The player's only control is to cause the ball to jump. My question is, what is the best way to make it appear to roll while generally keeping the ball at the same place on the screen? I have considered CCCamera, but it seems like it's not the best option since I want a repeating background image. Scrolling the background manually is also giving me trouble because it's not clear how to get the ball to stay in one place while letting Box2D handle the physics. I'd appreciate any help as I've been stuck on this for quite a while.
Use CCFollow on the layer where you draw the game stuff, and let it follow the ball sprite:
[gameLayer runAction:[CCFollow actionWithTarget:ball]];
I have a cocos2d game that has a loading scene where we load a bunch of assets. The game starts with the splash screen, and then launches the loading scene. The loading scene starts by loading the background, so the user sees the loading scene background while the assets are being loaded.
I load the loading scene background by calling CCSprite::spriteWithFile: and passing the filepath: loadingbackground.pvr.ccz
It seems to work differently on different devices:
On iphone (3gs) simulator, I see the loading scene as expected.
On iphone retina simulator, I don't see the loading scene (there aren't many assets yet, so may be happening quickly) and it goes directly to the main menu scene.
On the ipad 3 device, the splash screen comes up, and then there is a half second of black screen, and then the main menu scene shows up.
I want to see what I can do to avoid that black screen showing up on iPad 3. I suspect this is because of the time taken to load the loading background.
I have tried the following optimizations (mostly based on #Steffen's blog post on memory optimization):
Moved the loading background (originally 2.3 MB RGB8 png file) into a pvr.ccz spritesheet by itself, which reduced its size to 1.8 MB.
Removed the image from the texture soon after use.
I still see a black screen on iPad 3. Any suggestions?
Update: Found the issue - I had some code where I was overriding OnEnter and calling [[CCDirector sharedDirector]replaceScene] in it, and also calling the same from the background thread. Removed the OnEnter overload and it worked without flicker.
Thanks
Ignore whatever happens in Simulator. That's not relevant, focus on the device.
When the loading scene initializes and you add the loading scene's background, make sure you schedule update and load your assets in the update method. Otherwise if you load the assets in init, the background won't be drawn because you're loading all the assets before cocos2d gets to redraw the screen.
If this still fails, simply send the visit message to the background sprite followed by [[CCDirector sharedDirector] drawScene]. This forces a redraw of the scene.
Is this cocos2d-iphone or cocos2d-x ? make sure the tags are correct :)
I think you're referring to the startup flicker, there are a few ways to avoid that.
first thing you need to make sure you're handling the rootViewController correctly for iOS 6 and iOS 5 and below, there are a little changes for each.
You can find a little reference here:
http://www.cocos2d-iphone.org/forum/topic/34471
Second thing you need to know that simulator's behaviour is not stable, you should always rely on real devices for testing, but it's very likely you'll still have the flicker issues.
Sorry I didn't provide example code, but you haven't supported enough information to know what's the real issue here.
Just wondering how Cocos manages the CPU cycle and graphics engine for CCSprites that are offscreen, including those in the middle of an animation. If you have many animated sprites going on and off the screen, I could check and stop each animation when it's off the screen then restart it when it is about to come back on, but I'm wondering if this is necessary?
Suppose you had a layer with a bunch of them and you make the layer invisible, but don't stop the sprite animations. Will they still use CPU time?
I just did a quick test (good question :) ), in a game where i can slide the screen over a large map that contains images of soldiers performing an 'idle' animation. They continue running when off-screen (I tacked a CCCallFunc in a sequence in a repeat forever, to a simple selector that logs).
I suspect they would also run when the object is not visible. It kind of makes sense, especially for animations. If you look at my use case, if the animation were stopped, it could cause a cognitive disconnect if the user slided the soldier in and out of view, especially when the soldier is doing a walk on the map - he could actually walk-in the view without the user having done any interaction with the screen.