Masking Animation in cocos2d-x

Hi I am new to cocos2d-x. I learn and test masking animation with 2 picture in flash. I want to ask masking animation in cocos2d-x. I found this example and try this.
http://codewars.net/294/masking-with-cocos2d-x/
But this tutorial is only target to show the masking two sprite in initialization of an application. I want to make masking animation with run time(update).
Thank you very much.