Artificial Intelligence in Game Design
Tim Schreiner
Tim Schreiner
The explanation for the comparable shortness of this section in relation the previous one is twofold: one, Non-Combat AI is used much more infrequently in the game world, and two, I think it is a much more complicated and harder to implement form of game AI. I do want to briefly discuss it though, because it is also a very promising field of study, and one with more philosophical implications. Non-Combat AI can be seen all over Role Playing Games, in the role of Non-Playable Characters, or NPC's. NPC's help guide the player through the fantasy world, sometimes lending important advice or useful items. The big limitation to all NPC's is dialogue. Conversations must remain scripted; that is, the player is limited in the questions he can ask, and the NPC is likewise limited. Also, the NPC has no real memory as such, or any overt emotions or motivations or sense of right from wrong. The future of Non-Combat AI will involve real-time, dynamic conversations with infinitely different characters, all with their own agendas.
Before I move on, I should mention Black & White, Peter Molyneux's magnum opus game, wherein the player assumes the role of some god who must raise and train a given creature to carry out his every bidding. With a very simple interface (the game can be played with just the mouse), players can train their creatures to benevolent and helpful, or cruel and destructive, and it's all based on how the player and creature react to each other. The sequel was announced at E3 and should prove to be a very remarkable game.
The third possibility for game AI is, as far as I know, as yet unimplemented in any current games. However, its capabilities will very likely become beneficial in the not-to-distant future. I define Analytical AI as some form of AI intended to enhance the game experience, but not through a direct interaction between the player and the characters. For instance, Analytical AI might be used to run the traffic lights in a racing game, or control the number and difficulty of Combat AI opponents. It could monitor the player's health and reaction times and then adjust the damage taken or the speed of the opponents. In more complex levels, Analytical AI could provide subtle hints as to where the player should go next, such as making noises emanate from a room that the player is supposed to enter. Analytical AI is probably very difficult to implement at higher levels, but should be very feasible at tasks like balancing the difficulty for different players.
Efficiency AI is a little different. As the name suggests, Efficiency AI is designed to use all the CPU resources most efficiently at any given moment. A common use of Efficiency AI would be to postpone the pre-caching of a hidden section of a map because the player rarely seeks out secrets in lieu of just running through a given level. A more distant use might work in conjunction with external sensors. If eye-movement trackers become mainstream, Efficiency AI could put more colors and polygons in the players actual field of vision, which allows for much more complex graphics in comparison to rendering the entire scene at once.
With the increase in availability of faster Internet connections and better service and support, people are beginning to question the ultimate necessity of using Artificial Intelligence in games instead of a real person. The intent of this last section is to show that even faced with faster computers and connections, Artificial Intelligence will remain a fundamental element of game design, for three reasons: Lower-Level Positions, Upper-Level Positions, and the ultimate Need for Control.
As massively multiplayer games grow in popularity, it will become necessary to fill certain positions with some form of AI to keep the experience interesting for one simple reason: no one will want to fill that position. Before I go into the next part, I would just like to assert that I mean no offense to anyone reading this. With that said, I would think of any thing with waste maintenance. While few people would want to hold that position, there should still be some representation of every facet of life in a big city. For instance, a player and his party may decide to explore the sewers in the hopes of finding some lost item or secret entrance. Should they venture forth, there would need to be something keeping everything running smoothly in the sewers, making sure players aren't plotting some virtual terrorism or running a weapons trade, etc. I'm sure other people could come up with more examples, but you see my point: some positions won't be filled without AI.
Conversely, some positions should be filled by AI to limit the abuse of power. An example might be giants in a fantasy game. While the position is probably attractive to many players, the problems that could arise from an angry giant whose girlfriend just left him would be, suffice to say, detrimental to the experiences of the other players. While some developers have chosen to let members of the design team chair upper-level positions, at some point it will be necessary to use AI for any positions of great responsibility.
No matter how advanced games get, there will always be a need for control in games. Control serves a dual purpose, as it both ensures the game runs smoothly and keeps the experience enjoyable. The reason writers and directors get credit for their movies is because people don't just go to see the stars stumble around the screen (except possibly in the case of Titanic). Just as moviegoer's expect a level of control in the cinema, so do gamers want the occasional scripted sequence or limited set of actions. In games, AI represents some dynamic element that can still be reigned in if needs be.
No matter where technology takes us in the future, single player games will still exist, even if just to provide an environment where "venting steam" doesn't ruin another persons experience. And when, one day, game developers decide to leave every possible action and storyline up to the players, AI will still be used somewhere in games, even if the player cannot directly see it. As long as movies have scripts, games will have AI
Remember you can visit the Message Store to discuss this essay. Comments are always welcome!. There are already replies in the thread, why not join in?