Need help in understanding the positions of sprite in cocos2d?

I am new in cocos2d i have created a simple example

  CGSize winSize = [[CCDirector sharedDirector] winSize];
    CCSprite *player = [CCSprite spriteWithFile:@"Player.jpg" 
                                           rect:CGRectMake(0, 0, 27, 40)];
    player.position = ccp开发者_如何学C(player.contentSize.width/2, winSize.height/2);
    [self addChild:player];     

but I am not clear about the position of sprite how to manager it

Your code will create a sprite and position it within the parent node so that its lower-left corner is at ccp(player.contentSize.width/2, winSize.height/2).

If you wonder why your sprite is not centered respect to the coordinate you provide, the answer is that it is the lower-left corner which is positioned, not the sprite center.

You can tweak this behavior by defining the anchorPoint property of the sprite, like this:

 player.anchorPoint = ccp(0.5,0.5);
 player.position = ...

EDIT:

You can think of the anchor point as the "center of gravity" of the sprite: the texture is centered around it, any scaling or other kind of transformation will be relative to it.

If the anchor point is set at (0,0), then it coincides with the lower-left corner (default); if it is (0.5, 0.5) then it is exactly in the middle of the sprite (50% width, 50% height). Its coordinates are not point, but the relative displacement within the sprite; the coordinates can go from 0.0 to 1.0.