Recently it’s been easy to dislike Ethan Hawke. His tryst with a model on a film set led to the ending of his marriage to actress Uma Thurman, mother of his children. He wears his art-house credentials on his sleeve by supplementing his acting career by writing books.

The roles he’s best remembered for, such as Jesse in Richard Linklater’s Before Sunrise and Before Sunset, or Jake in Training Day, and, right at the beginning of his career, Todd in Dead Poets Society, are, to a man, pretentious idealists, and it’s often difficult to separate the actor from the man. With this in mind, it was a pleasant surprise to discover that the 37-year-old actor is immediately likeable, witty and a great raconteur.

His latest film, The Hottest State, is an adaptation of his own novel and stars Mark Webber and Catalina Sandino Moreno as young lovers. She’s a singer and he’s an aspiring actor from Texas who has moved to New York in search of fame and fortune. The Hottest State of the title is both a reference to Texas, where Hawke was born, and the emotional wreckage that is their relationship. The way the story is told in the movie is reminiscent of the work he’s done with Linklater, the same influence that can be seen in Julie Delpy’s film Two Days in Paris, which is closing this year’s EIFF. Hawke says of his association with the Slacker director: ‘I’ve done six movies with Rick Linklater [Tape, Fast Food Nation, Waking Life and the forthcoming Boyhood being the others] and so his impact on me and probably my impact on him is strong.

We’re like-minded people, he’s probably my best friend. I don’t know if I would have written The Hottest State if it wasn’t for Before Sunrise. There is a line in the movie where Sandino says: “When you’re young everyone tells you to follow your dreams and when you’re old they act offended if you try”. I remember when I was around 20 feeling so scared of trying anything different because people would mock or laugh at me. But Rick is one of those guys who wants everyone to succeed and he doesn’t see your success as a reflection of his own failure. He was an important person to meet at that age.’

It’s a sign of how young he was when he started acting that by the time Hawke was in his early-20s he was already getting cold feet about being an actor. He explains: ‘When I was writing the book, I was trying really hard to do something aside from movies. I did my first movie [Explorers] when I was 13-years-old and Dead Poets Society came out when I was 18 and by the time I was 25 I really wanted some other experience. I’d never been a professional anything else.’

Hawke followed up The Hottest State with Ash Wednesday. The critical reaction to his literary efforts has been decidedly mixed: the cognoscenti have deemed his books too whimsical while the young audience the books are aimed at have lapped them up. However, when Hawke first tried his hand at feature film directing he decided against adapting one of his own books in favour of Nicole Burdette’s play Chelsea Walls.

He says, ‘I really didn’t think of my book The Hottest State as a movie and then a few years passed and I started thinking that it would be fun to make. People began mentioning it to me a few times, and friends would say, “you should make this into a movie”. I never thought it was a good idea. Then I did Chelsea Walls and I met Mark Webber and I thought he would be the perfect actor to play William. Now I’m happy I did it, but funnily enough my favourite scenes are in the last 20 minutes and that stuff isn’t really in the book.’

There are several differences between the book and the film versions of The Hottest State, the biggest being that the couple do not visit Paris but head instead to Mexico, while Sarah (Moreno) is no longer a kindergarten teacher but a fiery Latin musician. Hawke says, ‘When you’re writing a book you’re trying to make literary references. So, I was trying with Paris to evoke the idea of the moveable feast. In the movie, I needed hot imagery if the film was going to be called The Hottest State. I wanted lots of images of fans and sweat. So I shifted it to Mexico. Funnily enough that gave me the idea that it would be fun to cast either William (Webber) or Sarah as a Latin person and I ended up casting Catalina. Then I thought it would be more dramatic to make her into a musician and that would be a big reason as to why he falls in love with her.’

Fans of Hawke’s acting talent need not fret as he has also given himself a role in the film, as Webber’s estranged father. Despite the break-up of his marriage, Hawke (unlike his character in the film), maintains a healthy relationship with his two kids Maya and Roan. They’re even heading out to Australia where Hawke is starring in vampire flick Daybreakers. The actor admits that one of the reasons he waited to shoot The Hottest State was so that he would be old enough to take the part. He says: ‘It was wonderful for me to imagine talking to my grown-up son. It was wonderful to imagine what he will look like, how nice it would be to see him and see that he was so handsome. I don’t know how I would’ve approached it if I wasn’t a father.’

The doting dad also looks much older in the flesh than he does on screen. His angular face is more pronounced and the facial hair he sports doesn’t take off any years. The big difference for Hawke between acting and directing a film is that he finds it much harder to come down to earth after he has been behind the camera. He admits: ‘Directing makes me a big whore for attention. I’ll get home and I’ll be alone and it will be so quiet and terrible and then I’ll get depressed for two weeks and then it will be alright.’

At the moment he has plans to write another book and to turn Ash Wednesday into a film. He says: ‘I’d love to do Ash Wednesday. It’s more cinematic, a better story, it has a beginning, middle and end. My hope is, though, to finish a new book before I do Ash Wednesday so I don’t run out of ideas.’

The Hottest State, Cameo, 623 8030, 16 Aug, 9.30pm & 17 Aug, 5.10pm, £7.95 (£5.50).