You're walking through a virtual world, beautifully rendered with cutting-edge graphics. Birds flutter overhead and sunlight glints off a nearby brook. The sense of immersion is immense. But try talking to anyone and the illusion is shattered.
Players can shoot, snowboard and conquer worlds but dialogue in games has never convinced anyone. Must conversation in computer games be so clumsy?
"At present, computer-controlled game characters are very two dimensional - essentially just moving images," says Kevin Warwick, professor of cybernetics at the University of Reading, in Britain. Warwick helps to run the annual Loebner Prize, in which computers are programmed to try to fool interrogators into thinking they are talking to a human. "A tough task," he says.
"Chat bots", however, manage to fool interrogators as often as one in four times. A chat bot is a computer program designed to simulate an intelligent conversation with one or more humans via auditory or textual methods. So why aren't game developers getting in on the act?
"The technology is there for conversations in computer games to be a lot better," says Warwick. "But game developers haven't put much time or money into this aspect - the visual perspective has been the main driver."
So while graphics have become almost photo-realistic, the way you "talk" in computer games has barely changed since the 1990s. If a player does initiate an exchange, the game's menus and pre-scripted conversation pathways immediately destroy any illusion of freedom.
Some designers, however, think change may be afoot. Robert Medeksza, who won the Loebner Prize in 2007 with his chat bot, Ultra Hal, says: "A general-purpose chat bot is expected to be able to converse about any topic the user can think of, which is virtually infinite."
That presents quite a challenge for a game's artificial intelligence (AI).
"If the range of topics the user is likely to discuss is well defined, such as within a quest in a game, then suddenly the problem becomes finite and considerably easier to make a realistic AI personality," says Medeksza.
He plans to test Ultra Hal in a computer-game setting.
"We will demonstrate the technology in a simple game where chatting with the AI characters will be an important part of completing a quest," he says.
At its core, Ultra Hal (a free copy of version 6.2 can be downloaded from www.zabaware.com/assistant) learns from previous conversations then ties this information into a huge database of words with layered relationships. Medeksza says AI-driven characters can help a player in their quest but they will not force users down any pre-determined paths, as many games' menu-driven systems do.
"The AI [will] try to lead the conversation and stay on topic in a way the game authors intend," says Medeksza. "But if a player chooses to speak off topic, [the] AI engine will be underneath ... and the character would be able to talk about anything at all."
To work in the context of a story, the chat bot needs to be integrated with the game engine.
"It's a matter of programming the game to communicate different states to the AI component. Like what stage of the game's plot you are at and the state of all the objects you are interested in," says Medeksza.
Other chat-bot designers are thinking along similar lines. Rollo Carpenter is a veteran developer who has been working on his Jabberwacky chat protocol since the 80s. His bots won the Loebner Prize in 2005 and 2006.
"I don't think that game creators have woken up to the social implications of an AI conversationalist that learns," says Carpenter. "Most approaches taken are orders of magnitude too simple."
Jabberwacky has been learning conversation patterns from online users for 10 years. Unlike more basic chat bots, his system actually replies in the context of the whole conversation. For some the experience is almost therapeutic.
"The longest conversation observed is 11 hours, with just three 15-minute breaks," says Carpenter.
With such abilities, AIs could be trained to drive the distinct personalities of in-game characters.
"Character and personality are hugely important," says Carpenter. "In addition to learning from and imitating the general public en masse, our Jabberwacky system invites people to sign up to create their own bot within it - to teach it to act like them, to impersonate them."
Perhaps games developers are starting to take notice. At this year's Electronic Entertainment Expo, in Los Angeles, the premiere trade show for computer games, software giant Microsoft showcased the Project Natal-powered Milo and Kate. A virtual boy who resides in a sunny landscape, Milo can apparently hold a natural conversation.
If there are game characters that talk, learn and have personalities, players can build a close affinity with them, says Warwick. "It's quite possible they will feel much closer to a character than they do to another human," he says. "I'm really surprised it hasn't been done commercially yet. I think this will push forward chat-bot technology pretty quickly when it happens."
With headsets fast becoming the norm in console gameplay, the conditions are good for developers to build chat technology into their games. Perhaps the industry will soon be standing at the dawn of a new computer-game genre: the first-person talker.
Guardian News & Media
