David Hockney: aged 74, the painter is as prolific (and perverse) as ever Hockney's substantial house is just off the seafront - it was once a small hotel, and numbers are still to be found above the bedroom doors. "This is a sort of marvellous bohemian life with a bit of comfort," he told me on that first visit. It's a long time since I've done any ambitious work in London, partly because I don't have too much space there and - more - because there are too many distractions. Here, I can paint 24 hours a day. Nothing else occupies your mind. Previously, Hockney has been based for two decades in Los Angeles, where - paradoxically - he also got a lot of solitude hidden away in his studio and house on Mulholland Drive. But, perhaps subconsciously in search of new subject matter and fresh challenges, his attention began to focus on the northern landscape of his youth. In 2004, he started to draw and watercolour the Yorkshire Wolds. It was, it seemed at the time, an audaciously old-fashioned thing to do. Conventional modern art wisdom held that naturalistic landscape was a worked-out genre; earlier artists had explored all the possibilities. It was impossible to do anything new. "But when people say things like that," Hockney responded, "I'm always perverse enough to think, "Oh, I'm sure it is." I thought about it, then I decided that it couldn't be true because every generation looks differently. Of course you can still paint landscape - it's not been worn out. Indeed, he seems to relish going against the grain and is an indefatigable controversialist and fervently pro-smoking. He has produced an official-looking notice, perhaps a bit of word art, that hangs on his studio wall. It reads: "Death awaits you even if you do not smoke." Recently, I noticed one of his helpers was wearing a T-shirt emblazoned "I Know I'm Right - D Hockney," a remark that Hockney's late friend the curator Henry Geldzahler used to claim was typical of the painter. "I'm a bit of a propagandist," Hockney admits. That comes from my father. Kenneth Hockney was also a campaigner for various causes, including - intriguingly - anti-smoking. "Dare to be a Daniel," he would instruct his children; his son David has taken that injunction to heart. Hockney's approach to the local landscape was to look at it: hard and harder and closer and closer. When we were first here, the hedgerows seemed a jumble to me. But then I began to draw them in a little concertina Japanese sketchbook. My assistant Jean-Pierre was driving, and I'd say stop, and draw different kinds of grass. I filled the sketch book in an hour and a half. After that, I saw it all more clearly. After I'd drawn the grasses, I started seeing them. This is crucial to Hockney's view of visual art; that it is all about seeing the world, seeing more in it, and more clearly. Eternal campaigner though he is, he is not much of a one for messages in art. Once at a press conference, Hockney was asked what his art was saying to people. He answered, "nothing specific, just love life." He likes to quote Sam Goldwyn's line about movies with messages - that he'd leave it to Western Union to deliver them. There is, however, a lesson of sorts in his work. The pictures could be saying, we're all on our own, looking. We are all on our own. Seeing more in the world around, and seeing it more clearly are great pleasures to Hockney. He has examined the undramatic landscape of the Yorkshire Wolds on every scale, employing old media and also very new ones. Having began with watercolour, he moved onto oil paintings done in the open, en plein air, in the manner of the impressionists. In 2007, he produced an outdoor epic, Bigger Trees Near Warter, at 40 feet across, perhaps the largest landscape ever painted entirely outside. Next, he moved from the vast, to tiny drawings, often ravishing, done on his iPhone and depicting such subjects as dawn rising over the sea outside his bedroom window and the bouquets that his partner John arranged on the sill. "I draw flowers every day," he would say at the time, "and send them to my friends, so they get fresh flowers every morning. And my flowers last. When the iPad was introduced, it quickly became his medium of choice (he uses an app called Brushes). It is well-suited to Hockney, who is a master draughtsman and also a colourist. Many iPad drawings, some printed out six feet high, will hang on the wall of the Royal Academy when the exhibition opens. While continuing to paint large-scale oils of small-scale subjects, such as undergrowth and foliage, Hockney also pioneered an entirely new medium. In the past couple of years, he has been making films - of a unique kind - using nine separate high-definition cameras, each angled slightly differently. The results, to be unveiled to the world in the exhibition, are like moving cubist collages. They are spectacular. "Put nine cameras together," he says, "and you suddenly get more interesting pictures. I've always believed that pictures make us see the world. Without them, I'm not sure what anybody would see. The task of the artist, as Hockney understands it, is to help us see more. That's what has kept him busy in Bridlington. Isn't that what you need? People who can see things from different points of view, looking at the world from a slightly different angle. Isn't that what artists do? "David Hockney RA: A Bigger Picture" is at the Royal Academy of Arts from January 21 to April 9 Martin Gayford is the author of "A Bigger Message: Conversations with David Hockney" (£18.95; Thames & Hudson), available from Telegraph Books for £16.95 + £1.25 p&p. Call 0844 871 1516 or visit books.telegraph.co.uk