For years, Zaha Hadid's architecture was problematic. Her ideas were stunning, particularly when ex-pressed as large paintings full of what seemed like exploding buildings, sharp angles and jagged planes, but many found it hard to believe that they could ever be built. From 1982, when she first sprang to fame winning the competition for The Peak, a mix of private club and apartments set high above Hong Kong, through to the debacle of the Cardiff Bay Opera House in 1994 (it was expected to win a Lottery grant but failed to do so and was cancelled), Hadid enjoyed immense critical acclaim and cult status among students, but frustration when it came to building. She managed to complete only one project, a little fire station at the Vitra furniture works near Basel. She appeared doomed to remain a paper architect, the fate of the great early-20th-century Russian suprematist Kasimir Malevich, who was such an influence on her.
Today, however, she seems omnipresent. Ever since she completed her first major building, the Lois and Richard Rosenthal Centre for Contemporary Art in Cincinnati in 2003, which brought her the prestigious Pritzker Prize the following year, Hadid has been unstoppable. Her BMW building in Leipzig - where conveyor- belts carrying cars from one part of the plant to the next thread their way dramatically between open-plan offices and reception areas - was shortlisted for this year's Stirling Prize. Later this month, the Phaeno Science Centre in Wolfsburg, her biggest building to date, which has rolling waves of concrete flowing like a tempestuous sea to create spaces that merge seamlessly one into another, will open with the world's media in attendance. Expect it to be favourite for next year's Stirling.
Now projects seem to flow from her pen: 2008 should see the completion of at least four major works, the CMA CGM head office in Marseilles, the Zaragoza bridge pavilion in Spain and a new Museum of Transport in Glasgow, as well as what is forecast to be one of the high points of the London Olympics, the £70m Aquatic Centre in Stratford. Hadid is on course to become one of the biggest forces in global architecture.
Meanwhile, a subtle shift in her work - or perhaps, more accurately, in the portrayal of her work - is becoming clear, a shift evident in the first new exhibition of her paintings for the better part of a decade.
Painting was a critical part of Hadid's early career. Most of her projects were worked out and presented in this way. With no buildings to look at, those trying to grasp what Hadid was about were forced to rely on them. To many, they seemed wilfully obscure; dramatic slashes, vivid colours, a powerful sense of movement and space, but little depiction of what the building would be like. There was a sense that if you did not understand what was going on, then tough. The initiates did, and that was what mattered.
Perhaps this is unfair. For Hadid, these early paintings were a way to explore the possibilities of buildings and space in an age before computer-aided design; an attempt to pin down in two dimensions the four dimensions needed to understand and appreciate buildings. Hadid was doing no more than Picasso and Braque seven decades earlier. What drove her was the desire to create an architecture that flowed, that was not constrained by the right angle. Of course, until her buildings were constructed, it was hard to understand what she was trying to achieve.
The new "Silver Paintings" are very different. Instead of abstractions of an idea about a building, they are representations of the building itself. The earlier paintings, created at a time when the pencil was still the primary design tool, were works of art in their own right. Today, architectural design relies overwhelmingly on the computer. These new paintings are essentially computer-generated images of buildings in the process of being designed, captured on computer as virtual photographs and then turned into paintings by the artist Antonio Carlos de Campos working for Hadid. Their title comes from the technique developed by de Campos, who uses a chrome polyester background (which provides the paintings' lustre), done using a spray-gun and masking tape.
Few would have difficulty recognising the resulting images as buildings. They have their own beauty, though they lack the raw energy that made the early paintings so exciting. But perhaps that is not surprising. Now that Hadid has real buildings to work on, not to mention computers that can generate any spatial experience she seeks, the intellectual need for spatially exploding paintings has gone.
Yet they also represent a personal Rubicon that she has already crossed. Hadid is no longer the wannabe avant-garde artist preaching to the converted, but a successful architect whose work includes company headquarters, sports buildings, speculative residential blocks and private houses, as well as cultural buildings. To be successful, her work needs to be understood. Hence the comprehensible images.
This is a dangerous moment for an architect. The cultists who have followed her for so long have a habit of getting nervous once the public come to enjoy what was once their private preserve. In some quarters, Daniel Libeskind's critical reputation has never recovered since he made the egregious mistake of becoming popular. Will Zaha Hadid suffer the same fate?
"Zaha Hadid: Silver Paintings" is at Kenny Schachter Rove, 17 Britannia Street, London WC1 until 26 November
Giles Worsley is the architecture critic of the Daily Telegraph