CCMask

CCMask is a class which makes masking in Cocos2D-x v2.0 fairly easy.
You just have to define an object and a mask. And that's it!

Usage:

// Create a mask and an object
CCSprite* mask = CCSprite::create("mask_circle.png");
CCSprite* object = CCSprite::create("HelloWorld.png");
object->setPosition(ccp(mask->getContentSize().width/2, mask->getContentSize().height/2));

// Create a masked image
CCMask* masked = CCMask::create(mask , object);
masked->setPosition(ccp(size.width/2, size.height/2));
this->addChild(masked);