London - Fresh out of jail and sporting tattoos on his neck and knuckles, 53-year-old Shaun Perkins sits in one of London's oldest gay pubs looking bewildered.
"When you're in prison, they put you in a cell and it's like time stands still," he said, dressed in a leather jacket and jeans.
Staring at a gaggle of straight young women in smart casual wear and polka-dot dresses, he said: "Everything's changed. You wouldn't have seen girls in a place like this."
In the 13 years that Perkins was jailed, London's gay scene has transformed.
Several venues have either closed down or become more open to straights, and many gay people are frequenting mainstream venues amid an atmosphere of greater tolerance.
Others are ditching bars and clubs altogether, and with the proliferation of dating websites and mobile phone apps, are choosing to make contacts online.
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Lesbian, gay, bisexual and transgender (LGBT) campaigners say that as many as a quarter of London's gay venues have closed in recent years as luxury flats and chain stores mushroom, threatening to undermine the city's status as one of the world's gay capitals.
"I made a special effort to come here from north London. There's absolutely nothing there now," Perkins said as he sat in south London's Royal Vauxhall Tavern.
A Victorian circular pub featuring classical columns, a wooden bar and a stage draped with red curtains, the tavern is billed as Britain's oldest LGBT pub.
Its advocates cite reports of drag acts here, female impersonation shows, as far back as the 1880s.
The venue was sold to developers last year and is now under threat of closure, according to campaigners who are fighting for it to be protected as a listed historic building.
Gay bars doomed?
The developers, Immovate, say they want to keep the pub open but argue that it is a loss-making business that only survives because they do not charge any rent on the property.
They warn that a listing, backed by London mayor Boris Johnson and actor Ian McKellen, would only make things worse by imposing higher insurance premiums on the venue.
"When developers talk about commercial viability, what they really mean is maximum profit," countered Ben Walters of RVT Future, the campaign to keep the venue open.
"For any site in central London in 2015, maximum profit is not going to come from operating as a gay pub, however successful. It's going to come from being developed as flats and retail."
The Royal Vauxhall Tavern may be a historic venue, but as visitor numbers dwindle at other gay pubs and clubs, some question whether such venues are really needed any more.
London is one of the world's most gay-friendly cities, and many LGBT people feel welcome in mainstream establishments.
"Gay bars, as they are now, are doomed. Speaking for myself, I feel just as comfortable going to a gay-friendly bar as a traditional gay bar," said Fernando Formoso, 42, a civil servant.
The days of trawling of gay pubs for a date or sex are largely over too, with thousands of potential contacts available on dating apps.
"Going online is cheaper and more convenient, you don't have to leave your house," said IT trainer Mike Pettet, 41.
'Queer spaces beyond pubs'
Campaigners for gay venues say that they can be more than just places to socialise.
East London's Joiners' Arms, which closed in January after being sold to developers, hosted gay community meetings with the police, HIV testing and fundraising events.
Activists also warn against complacency, and point to rising homophobic crime and cuts to gay community services as part of the government's austerity drive.
"It's good that mainstream tolerance seems to be increasing, but history tells us things can go backwards fast," said Walters, from the Royal Vauxhall Tavern campaign.
He does not advocate "preserving all gay bars at all costs", but says London's extreme commercial pressures were making it hard for new types of LGBT venues to find a foothold.
"We need queer spaces beyond pubs and bars, such as arts and community venues. But it's a battle to keep what we've got, let alone move things forward," he said.
Back at the tavern, performer Ursula Martinez is dressed in a flamenco-esque outfit and eliciting howls of laughter with songs about sex and race.
"Viva la liberacion sexual! Viva la integracion cultural!" she said, with a final strum of her guitar.
Perkins, seeking a more traditional scene, had disappeared.