Freeman of Bradford

Went to the David Hockney exhibition at the National Portrait Gallery on Saturday. Worth it, for one - a lot of stuff that doesn't get out too often. Some points.

Hockney's always struck me as one of few painters who are funny. Not comical, but humour is part of the language. Looking at his Rake's Progress, visual gags are a serious theme, as they were in the original. A sign reading BAR CLOSED peeks out of a corner at an election meeting. Among the Good People, a gospel singer performs with breasts like rugby balls, as a halo precisely the same shape executed in deadpan ink hovers over her head. For some reason I misread the blockprint title Receiving the Inheritance as Receiving the Nightmare, which feels significant even if it's not.

The Rake's is the only one of Hockney's pictures before the 1990s that shows any change in the Hockney figure. He lands as a geekish scholar who somehow looks pale although he is a line drawing on white paper, but half-way through suddenly appears in squarish specs, two-tone shoes and a T-shirt. It's the only Hockney moment that makes any concession in the figure of the artist to the United States, although he's lived there for most of his life. (Soizick argues it reflects a coming-out experience.)

Otherwise, he doesn't change through 30-odd years of portraiture, from the rediscovered kitchen sink self-portrait done at the age of 17 in his dad's attic in Bradford, which could as well be titled Bradford Grammar School Angst, until he starts his camera lucida paintings in the 1990s. Terry Eagleton said the Scholarship Boy, along with the Dumb Blonde and the Mad Scientist, was one of the crucial characters of the 20th century. The Hockney figure is much the same. His The Student: Homage to Picasso shows a Hockney in flapping strides, funny hat, long hair and embarrassing outsize easel approaching the master, whose head is mounted on a pompous classical column and who wears a Hitler fringe.

Homage? Picasso looks as silly as any authority does to the Student, who looks as silly as...well. And he knows it, painfully. It's brilliant, largely because it is funny. (At first sight, I thought the Picasso head was eyeing the student warily, as if to put him off or wondering what embarrassing horrors he might come up with, but studying the image, this seems to be another of my projections.)

This sort of askew view holds up the best of his work. Forget the studly tennis coach lovers for a while. In fact, fuck'em. Forget the glamourpuss stuff more widely. Consider the huge Henry Geldzahler and Christopher Scott. Geldzahler (a curator at the New York Metropolitan Museum) is enthroned on a huge sofa, clearly interrupted while talking. It's instantly clear he talks a lot, but the light is twanging off his specs from the city outside - does he make sense? The viewpoint lunges forward, tilting the perspective queasily short and making the sofa look aggressive, as if it might throb menacingly if you took your eyes off it. Bang! Here is Scott, plonked suddenly at 90 degrees to the thing, standing nearly at attention in a scruffy raincoat as if teleported from Bradford in 1954. Geldzahler seems to be about to use him to demonstrate a point, like a lecture hall skeleton - or is he waiting for a message from him?

This sense of time made visual is vital - J.G. Ballard devoted a whole essay to the idea in Hockney. So many portraits here are doubles. It's a way of guaranteeing they won't sit still, or at least not both at the same time. Hence the photo-mashups. One here, from Hockney's own collection, shows Billy Wilder lighting his cigar from behind gangsterish sunglasses. It's a record of a total gesture and possibly more about the man.

Another Hockney gear is detail, and there are an enormous number of his drawings to support it even before the camera lucida ones. His fellow Freeman of the City of Bradford, J.B. Priestley, "just sat there looking big", apparently. Hockney drew him in a pose, with his pen poised, that echoes the 18th century portraits upstairs in the NPG historical collection - Samuel Johnson and company. Priestley looks wise and funny, like his books. In the same series, W.H. Auden (another Yorkshire modernist) looks uncannily like Denis Healey, and Stephen Spender looks pompous. Andy Warhol is dressed like David Cameron.

But the best drawings are the ones of his family. I can think of nothing better than that I thought I had sat next to every one of them on a bus in Bradford.