The industry of video games has rapidly grown during the last decade, while “gaming” has been promoted into an interdisciplinary stand-alone science field. As a result, music in video games, as well as its production, has been yet a state-of-the-art research field in computer science. Since the production of games has reached a very high level in terms of complication and cost (the production of a 3-d multi-player game can cost up to millions of dollars), the role of sound engineer / composer / programmer is very crucial. This chapter describes the types of sound that exist in today's games and the various issues that arise during the musical composition. Moreover, the existing systems and techniques for algorithmic music composition are analyzed.
TopIntroduction
Sound is a very important part in a video game. It helps the player to integrate into the game and the character. By the term audio we refer to all the sound elements that make up a game: sound effects, dialogues, songs, background music and interface sounds. Depending on the type or the mechanics of the game, there is a different relationship between all these elements. Nevertheless, these elements contribute to the experience enjoyed by the player when playing a game.
In the video games sound is vaguely referred to as “interactive”, “adaptive” and “dynamic”. However, there have been efforts to separate these three concepts. Interactive is the sound that happens as interplay to the player’s moves. When the player presses a button, the character, for example, will shoot and then a certain sound will be heard, which is going to happen each time the player shoots. On the other hand, the adaptive sound does not interfere with the player's moves, but adjusted according to changes that occur in the game, such as the music in the video game Super Mario Brothers (Nintendo 1985), which while playing in a steady rhythm, changes when the time finishes. The term “dynamic” sound includes the above two conditions. So is the sound that interacts on player’s actions, but also the flow of the game.
In a video game, players react in proportion to the sounds they hear apart from the image. There are games that are based on sound, and are ideal for players with visual impairments. Such games create an environment in the player's mind, which uses different sounds produced to move through the game. One such example is the game Papa Sangre (2010). It is a sound game in which the player moves in 5 castles trying to avoid monsters in order to collect musical keys. Monsters react to sounds produced by the player, if they run or push an object, so the player learns to listen carefully as moves in the game, and pays attention to all sounds.
Figure 1. Game surroundings in Papa Sangre
Contrariwise, in games that combine sound and image, an inseparable relationship is created: sound makes us see a picture differently, and this in turn makes us listen the sound differently etc. The console Atari 2600, released in the late 1970s, had very poor graphics and audio capabilities. The pictures looked like large pixel pieces with result that if someone that was out of the game saw them, would be unable to make sense. On the other hand, most sounds were very hard and had nothing to do with natural sounds. However, when combined sound and image, acquired meaningful game. So we can understand that short bursts in the game Combat (1977) is actually cannon blasts, and the hollow noise that sounds continuously is a moving tank.
Figure 2. Combat (1977): In the game appear two tanks moving between walls