Mumbai, March 2 (IANS): Actor Ranbir Kapoor, who started his career as an assistant director to filmmaker Sanjay Leela Bhansali, says if he has to pen down a portion of his life, then it would be the time when he assisted Bhansali on the film "Black".

He says that phase transformed him completely from an "aimless slacker boy to a worthy person".

"I have not thought about it (writing a book) at all. I have miles to go before I can think of something like that,"the 32-year-old told reporters here at the launch of cover of Ronnie Screwvala's book "Dream With Your Eyes Open".

"But if I had to, then it would be the time when I assisted Mr. Bhansali (Sanjay Leela Bhansali) on 'Black', because that was the time I really switched from just being an aimless slacker boy to somebody who wants to do something in his life related to films," he added.

Before foraying into acting with Bhansali's directorial "Saawariya" (2007), Ranbir worked as an assistant director with Bhansali. Although the film didn't work, however, Ranbir was noticed for his performance and he bagged Filmfare's Best Male Debut Award.

Further, he praised the National Award winning director and said: He was a great mentor, he was a great teacher, so to write something about that would be interesting."

Meanwhile, Ranbir is awaiting the release of his film "Bombay Velvet", directed by Anurag Kashyap.