Robert Pattinson "all smiles" at Cosmopolis premiere

Robert Pattinson was "all smiles" at the Cosmopolis premiere after party on Monday (August 13).

The 26-year-old actor - whose girlfriend Kristen Stewart admitted to an affair with Rupert Sanders last month - appeared to have put his recent problems behind him when he arrived at the PH-D Rooftop Lounge at Manhattan's Dream Downtown hotel at around 10 pm, with onlookers describing him as "relaxed and comfortable" at the bash, despite the attention he attracted.

A source told People: "He was very charismatic, all smiles, looking very relaxed and hugging all who stopped by to say hi. The general crowd gravitated towards his table, but he was shielded by security. He was surrounded by women and the movie's cast."

"The whole room was watching him, and he looked genuinely at ease and comfortable the whole time." The evening capped off the first time Robert has appeared in public since the news of Kristen's affair broke, walking the red carpet at the New York movie premiere having earlier taped an episode of The Daily Show.

At the Cosmopolis screening, the Twilight Saga star admitted he felt "absolute terror" about getting close to his fans following his personal problems.

He said: "I felt fear, absolute terror. It's great - I didn't expect it from the first Twilight movie, I never expected my life to be like this and so it's kind of weird to have lasted. And for people to come to movies that I'm really like proud of and I didn't really think anyone's going to see, I mean it's like, it's kind of amazing."

Robert Pattinson poses nude in 13-hour photoshoot

In a photoshoot for French magazine 'Premiere' Robert Pattinson can be seen lying naked on the mattress with just a red silk blanket covering his modesty as he gazes at the heavily pregnant female.

The bed is scattered with videotapes and the British actor looks pale and tired as he stares at the dark-haired female.

The unique shoot is said to have lasted 13 hours and was an idea of the 25-year-old actor who wanted to dedicate it to director David Cronenberg's movies.

The images are apparently a homage to his respect for the filmmaker, who by casting him in Cosmopolis, offered him not only a passport following the success of 'Twilight' but also the opportunity to come and celebrate his entry to the adult age, on the steps of Cannes on May 25.

"Filming Cosmopolis with Cronenberg changed something in me. It gave me balls," the Daily Mail quoted him as telling the magazine about his latest role.

In the upcoming drama, which is based on the novel of the same name by Don DeLillo, Pattinson portrays billionaire Eric Packer who goes on a trek across Manhattan to get a haircut.

The actor - who is best known for his role as vampire Edward Cullen - clearly has a lot of respect for Cronenberg and is grateful for the opportunity.

"I'd never worked with a screenwriter who was this confident in his abilities,' Pattinson added. 'If he was stuck on a way to film a scene, he did something else. He knew the script by heart so he could afford it. It's kind of unnerving at first, but since I'm in every scene I memorised the whole script, like a play," he said.

However, Cronenberg is said to have admitted that Pattinson was stressing out about filming Cosmopolis, and he decided to shed some light on why.

"I'm going through a phase were I'm trying to determine what I can accomplish or not as an actor," Pattinson said.

"It's even more complex when you know you have a past, even though people like David don't pay any attention to it," he said.

With the release of Breaking Dawn: Part Two this November, Pattinson will finally be kissing his Twilight day's goodbye and is curious as to how the hysteria may change.

"I'm going to be 26 and I can tell you that it's starting to freak me out that I'm appealing to girls that are 13-years-ol," he said.

"I'm often wondering how things will change now, but I can't believe there's still one more to come," he added.