Ragdoll floppiness can, however, offer its own kind of fun. Mark Healey, one-time artist at Lionhead Studios, had always fancied making a small Street Fighter-type game that used the mouse; he'd also made a short kung fu movie with some mates. Once he'd combined these ingredients with a piece of code that simulated virtual rope, Rag Doll Kung Fu was born. "There is no animation in that game whatsoever," says Healey. "When the AI characters move, they're controlled in the same way that you control your character - by picking up limbs."
For Healey, it was the very stupidity of ragdolls that made them so much fun. "In my opinion," he says, "the best thing about using ragdoll physics in Rag Doll Kung Fu was that it allowed players to act with the character. I remember crying with laughter many times as someone showed me a new silly walk they'd invented. It let players add their own personality to the game."
Despite such departures, however, ragdolls are destined to become less funny as they evolve. Increasingly, developers are likely to use ragdoll physics in concert with animation. For example, a character on a moving platform will be able to automatically compute their centre of balance. They'll lean forward or backwards as they run up or downhill, and 'recover' when punched, switching between user and game control as appropriate. "We're just scratching the surface at the moment," says Collins. "We'll know we're there when no one notices ragdoll technology any more - just a convincingly realistic portrayal of a game character."