interactiOn mOdel

           The user interface turns the player's inputs on the hardware into actions within the game world.The relationship between the player's inputs and the resulting actions is dictated by the game's interaction model.The model determines how the player projects her will,her choices and her command, into the game.In particular,it define what she may and and may not act upon at any given moment.Video games use a number of standard interaction models,including multipresence,avatar-based models,contestant models and so on.

Interaction  model are features of the user interface.

        
          In a multipresent model,for example can act on different parts of the game world whenever she wants to,reaching "into" it from the "outside".In an avatar-based model,the player is represented by a character who already is inside the game world,and the players acts on the world through that character.Just as the visible parts of a game's user interface change during play, a game can have more than one interaction model depending on what is happening at the time.

source from : Fundamnetals of Game Design , Ernest Adams

Types of Interaction Models

• Avatar based
• Multipresent
• Party based
• Contestant based
• Desktop

Avatar Based

• Player controlling a single character, the avatar in the game world.
• Player acts upon the world through his avatar.
• Example of game : Diablo

Multipresent

• Player can act upon several different parts of the game world at a time.
• Example of game : Age of Empire (online)

Party Based

• A small group of characters generally remain together as a group.
• Example of game : Dragon Age : Origins

Contestant Based

• Player answers questions and make decisions.
• Usually no navigation available.
• Example of game : Wheel of Fortune

Desktop

• Mimics a computer desktop
• Usually found only in games that represent some kind of office activity.
• Example of game : Industry Player