Mumbai:Celebrated author Chetan Bhagat, who is co-producing the upcoming film adaptation of his novel “Half Girlfriend”, has been spending time at the shoot of the film. He says filmmaking requires more “hard work” than writing a book. Directed by Mohit Suri, “Half Girlfriend” stars Arjun Kapoor and Shraddha Kapoor. The film is currently under production. Bhagat took to Twitter on Monday to share his experience from the film's set. “First time on film set from start to finish. So much hard work! New found respect for filmmakers. Pen and paper so much simpler! 'Half Girlfriend',” he tweeted. This is not the first time that Bhagat's book is being adapted for the screen. His previous novels like “Five Point Someone”, “One Night @ the Call Center”, “The 3 Mistakes of My Life” and “2 States: The Story of My Marriage” have earlier been adapted into films. “Half Girlfriend” is set for a worldwide release on April 28 next year.