|cocos2d best practice

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CCDirector 

-> DisplayLink (MainLoop, ThreadMainLoop)

Texture Atlas 

-> CCSprite (from CCSpriteSheet),

    CCBitmapFontAtlas or CCLabelAtlas (instead of CCLabel), 

    CCTMXTileMap or CCTileMapAtlas to render tiles

  => provide faster rendering 

Texture

-> 16-bit : png, gif, bmp, tiff images

        ex) [CCTexture2D setDefaultAlphaPixelFormat:kCCTexture2DPixcelFormat_RGBB4444];

            4-bit, 2-bit : PVRTC

ex) CCSprite *sprite = [CCSprite spriteWithFile: @"sprite.pvr"];

Particles

-> faster at 1st and 2nd gen devides, but slower 3rd gen devices / iPad

Reducing Memory

-> use 16-bit or 4-bit textures

    use CCTextureCache (:caches all images, even not used image is remain in memory)

    To remove it from memory do:

ex) [[CCTextureCache sharedTextureCache] removeUnusedTextures]; // v0.8 ~

      ---------------------------------------------------------------------------------------

      CCTexture2D *texture = [sprite texture];

      [[CCTextureCache sharedTextureCache] removeTexture: texture]; // available in v0.7 too 

      ---------------------------------------------------------------------------------------

      [[CCTextureCache sharedTextureCache] removeAllTextures]; // available in v0.7 too

Timers

-> Not to use Cocoa's NSTimer instead use cocos2d's own scheduler

    cocos2d's scheduler : automatic pause/resume,

    : CCLayer(CCScene, CCSprite, CCNode) enters the stage the timer will be automatically activated and when it leaves the stage it will be automatically deactivated,

Your target/selector will be called with a delta time

Draw vs. update

-> draw selector : try not to update any state variable inside here -> pause/resume won't work as expected

  : draw everything inside here

    scheduled selector : try not to draw anything inside here -> it can't be transformed

      : update the state variable inside here

    draw is called every frame

    scheduled selectors can be called with any frame rate, but no more frequently than the applecation's FPS rate

Director flow control

-> If possible try to use replaceScene instead of pushScene

      pushScene is very handy, but it will put the pushed scene into memory, and memory is a precious resource in the iPhone

ex) [[CCDirector sharedDirector] pushScene: gameScene]; (X)

      [[CCDirector sharedDirector] replaceScene: gameScene]; (O)

Creating Nodes(CCSprite, CCLabel, etc….)

-> possible try to create CCNode objects (CCSprite, CCLabel, CCLayer, etc) in the init selector and not in any other scheduled selector,

           the creation of nodes expensive, so them pre-created. but if you don't use them frequently memory is wasted

Hierarchy of Layers

-> Don't create a big hierarchy of layers. Try to keep them low when possible

Actions

-> It is expensive to create certain actions since it might require a lot of malloc(). So try to reuse actions.

           Once the action is used, save it for later if you know you will execute that type of action again. 

    Then, instead of allocing a new action, you can just initialize it..

 Buttons

-> Use a Menu with a MenuItemImage and place your menu using meno.position = ccp(x,y). See the MenuTest example for more details

 How does the pause/resume works?

-> when the director receives the pause message it won't call any scheduled target/selector.

    but the draw selector will be called at a rate of 4 FPS (to reduce battery consumption)

    when the director receives the resume message, the scheduled target/selectors will be called again every frame.