Basic sprite masking

gistfile1.m

- (void)visit {
  if(self.mask) {
    self.bakedTexture = [CCRenderTexture renderTextureWithWidth:self.contentSize.width
                                                            height:self.contentSize.height];
    self.bakedTexture.position = ccp(self.contentSize.width/2,self.contentSize.height/2);
    [self.mask setBlendFunc:(ccBlendFunc){GL_ONE, GL_ZERO}];
    [self.bakedTexture begin];
    [self.mask visit];
    for(CCSprite *sprite in self.assets) {
      [sprite setBlendFunc:(ccBlendFunc){GL_DST_ALPHA, GL_ZERO}];
      [sprite visit];
    }
    [self.bakedTexture end];
    [self addChild:self.bakedTexture];

    self.mask = nil;// Don't do this again...
  }
  [super visit];
}