in this video https://www.youtube.com/watch?v=RnXDUFq7T6A&lc=z22rvjvg0tqqyphk2acdp43av5yx4wdt1qiuys32oj1w03c010c.1510388919395141​ 

why do you need color attribute in this cube, if we dont see colors of shaders under texture? Also, why is there (2,2) in vertextattribute for positions of texture? Sorry, i can read english, but i dont always understand it, when people speak